[1]

SUMMER SCHOOL ON OPTICS &

PHOTONICS 2017

Book of Abstracts

Oulu, Finland, 1-3 June, 2017

[2]

Editors

Motahareh Peyvasteh, Alexey Popov, Igor Meglinski

Optoelectronics and Measurement Techniques (OPEM), Faculty of Information Technology and Electrical Engineering,

University of Oulu, Oulu

motahareh.peyvasteh@oulu.fi

alexey.popov@oulu.fi

igor.meglinski@oulu.fi

© 2017 University of Oulu

This work is subject to copyright. All rights are reserved. This work may not be translated or copied in whole or in part

without the written permission of the publisher (University of Oulu).

www.oulu.fi/photonics2017

mailto:motahareh.peyvasteh@oulu.fimailto:alexey.popov@oulu.fihttp://www.oulu.fi/photonics2017

[3]

Table of Contents

Welcome ............................................................................................................................................................ 5

Organizing Committee ...................................................................................................................................... 6

Sponsors ............................................................................................................................................................ 7

Partners .............................................................................................................................................................. 8

Program ............................................................................................................................................................. 9

Posters ............................................................................................................................................................. 12

Oral section

Light microscopy and algorithm based mathematics to analyze cancer cell movement using 3D in vitro

matrix models .................................................................................................................................................. 15

Study of birefringence alterations during optical clearing of biological tissues .............................................. 16

Raman and ATR FTIR spectroscopy in the study of chemical reaction rates ................................................. 17

Toward virtual biopsy. Multimodal spectroscopy for cancer detection .......................................................... 18

Laser-induced surface graphitization of diamond for metamaterial fabrication .............................................. 19

Physical principles of design of metamaterial absorber based on electrical ring resonators ........................... 20

Influence of glucose concentration on blood optical properties in THz frequency range ............................... 21

Advancing optical coherence tomography with numerical techniques ........................................................... 22

Optical tweezers: principles and selected applications .................................................................................... 23

Spectral investigation of ultranarrow-linewidth distributed-feedback resonators below laser threshold ........ 24

Remote photoplethysmography system for contactless regional anesthesia monitoring in operating room ... 25

Nanodiamond structures for fiber optics devices ............................................................................................ 26

Imaging of extracellular nano vesicles exosomes in mental health ................................................................. 27

Mitigating transmitter non-linearity and fiber impairments in radio over fiber technology............................ 28

Short-range supercontinuum LIDAR for temperature profiling ...................................................................... 29

Fabrication of novel organic and inorganic thin film transistors and exploration of subgap density of states 30

In-vitro investigations on fluorescence behavior of urinary and kidney calculi .............................................. 31

Simulations of terahertz wire-grid polarizers on substrate .............................................................................. 32

Wavelet analysis for Terahertz time domain spectroscopy ............................................................................. 33

Poster Section

Optical tweezers: probing effect of nanoparticles on red blood cells aggregation .......................................... 35

Determination of Doppler angle based on the carrier spectrum broadening ................................................... 36

Tomographic phase microscope for study of mouse fibroblast ....................................................................... 37

Terahertz dielectric lens for super-resolution images ...................................................................................... 38

Dynamic tuning of graphene plasmonic resonances by ultraviolet light ......................................................... 39

Control the optical properties of phosphate glass with CdSe quantum dots in terahertz frequency range ...... 40

Analytical model to describe fluorescence spectra of human skin .................................................................. 41

[4]

Table of Contents

Optical surface evaluation of bone implants during its processing ................................................................. 42

Density of quantum states in periodical structures .......................................................................................... 43

Narrowband optically tunable terahertz filter based on graphene for biomedical applications ...................... 44

Optical forces and torques action on birefringent microplate ......................................................................... 45

Possibilities of application of fluorescence spectroscopy in minimally invasive surgery for analysis of

abdominal cavity organs pathological processes ............................................................................................. 46

Possibilities of Doppler spectrum analysis of laser radiation received from hand skin during functional tests

......................................................................................................................................................................... 47

Epsilon-near-zero copper-dielectric composite for terahertz frequency range ................................................ 48

Projection on latent structures method for analysis of blood plasma Raman spectra ...................................... 49

Laser diagnostics method for evaluation of properties of blood flow oscillationsin rheumatologic patients . 50

Polarazing properties of metasurface based on chiral unit cell in THz frequency range ............................... 51

Stokes correlometry of polarization inhomogeneous object fields .................................................................. 52

Meat freshness inspection by visible and near-infrared spectroscopy ............................................................. 53

Non-invasive evaluation of skin pathologies by RGB autofluorescence imaging .......................................... 54

Microwave vortex field ................................................................................................................................... 55

Laser speckle contrast imaging of a transition from non-ergodic to ergodic light scattering.......................... 56

Fluorescence spectroscopy usage possibilities for the laboratory rats metabolism evaluation ....................... 57

Using of Raman spectroscopy method in comparative spectral analysis of the surface of aortal valves of the

hert of baranes before and in process of their decellularization ...................................................................... 58

Lab-on-a-chip system for the analysis of biofluids ......................................................................................... 59

Raman spectroscopy of human sweat components ......................................................................................... 60

Imaging of rhodamine-loaded capsules distribution in vivo by fluorescence spectroscopy ............................ 61

Research studies of aging changes of hyaline cartilage surface by using Raman-scattering spectroscopy..... 62

Quantitative assessment of skin composition and scattering properties in human volunteers using

photothermal radiometry and diffuse reflectance spectroscopy in vivo .......................................................... 63

Graphene enabled active optical fiber devices ................................................................................................ 64

Diagnostics of singularities inherent in combined beams assembled from uncorrelated Hermite-Gaussian

modes ............................................................................................................................................................... 65

Application of adaptive wavelet-analysis for the study of cutaneous blood flow oscillations in patients with

diabetes mellitus .............................................................................................................................................. 66

Author index .................................................................................................................................................... 67

[5]

WELCOME

On behalf of the University of Oulu SPIE Student Chapter, we warmly welcome Doctoral Students,

Young Researchers and SPIE/OSA Members to attend the Photonics Summer School on 1-3 June

2017 in Oulu, Finland.

The SPIE FOCUS conference is organized for the first time in Finland, by the Northernmost SPIE

Student Chapter. The untouched Northern nature in combination with the high-tech environment

inspire PhD students and young researchers from all around the world to feel the vibrant spirit of

Photonics-Photonics with the Arctic attitude!

You will benefit from

• Development workshops

• Meeting with local companies

• Lectures, presentations and poster sessions

• Meeting with renowned International researchers and experts

• Discovering recent trends in Photonics, Optics and Optoelectronics

• Discovering the beauty of the Finnish midnight sun

• City tour and unforgettable Finnish cuisine

We wish you a fruitful conference and a pleasant and memorable stay in the Capital of Northern

Scandinavia!

On behalf of the Program and Organizing committees,

Assoc. Prof. Alexey Popov and Prof. Igor Meglinski,

Chairs of the Summer School

Website: www.oulu.fi/photonics2017

http://www.oulu.fi/photonics2017

[6]

ORGANIZING COMMITTEE

Organizing Committee

Chair

Lukasz Surazynski

Vice-Chair

Aleksandra Zienkiewicz

Members

Pauliina Vilmi

Tatiana Avsievich

Motahareh Peyvasteh

Anton Sdobnov

Yana Tarakanchikova

Maria Borovkova

Prateek Singh

Lassi Rieppo

Vesa Korhonen

Veli-Pekka Ronkainen

Mika Kaakinen

Sami Huttunen

Lauri Eklund

Eija Pajunen

Alexey Popov

Igor Meglinski

Program Committee

Chairs

Dr. Alexey Popov (University of Oulu, Finland)

Prof. Igor Meglinski (University of Oulu, Finland)

Members

Mikhail Khodzitsky (ITMO University,

Russia)

Malgorzata Jedrzejewska-Szczerska (Gdansk

University of Technology, Poland)

Kurias Markose (Cochin University of

Science & Technology, India)

Matiss Lacis (University of Latvia, Latvia)

Pavlo Ryabyi (Chernivtsy National

University, Ukraine)

Bohdan Sokolenko (Taurida National V.I.

Vernadsky University, Ukraine)

Svyatoslav Gusev (ITMO University, Russia)

Lauri Eklund (University of Oulu)

Vesa Kiviniemi (University of Oulu)

Nikolay Brandt (Moscow State University)

Participating SPIE Student Chapters

University of Oulu (Finland)

ITMO University (Russia)

Gdansk University of Technology (Poland)

Cochin University of Science & Technology

(India)

University of Latvia SPIE Chapter (Latvia)

Taurida National V.I. Vernadsky University

(Ukraine)

Chernivtsy National University (Ukraine)

[7]

SPONSERS

[8]

PARTNERS

[9]

PROGRAM

DAY 1, co-located with the Oulu Bioimaging Day - OBI Day (1.6.2017)

Place: Saalasti Hall, Linnanmaa, University of Oulu

Session 1, Chair: Docent Lauri Eklund

09:00 - 09:10 Jukka Riekki, Dean of Faculty of Information Technology and Electrical Engineering,

University of Oulu: Welcoming speech

09:10 - 09:15 Lauri Eklund, Biocenter Oulu, University of Oulu: Opening Oulu Bioimaging Day

09:15 - 09:30 Sinikka Eskelinen, Faculty of Medicine, University of Oulu: Past, current and future

perspectives of Oulu Bioimaging

09:30 - 09:55 Zeev Zalevsky, Bar-Ilan University, Israel: Usage of light for remote and simulataneous

"hearing" of many physiological parameters (Keynote)

09:55 - 10:15 Sponsored Coffee

Session 2, Chair: Dr. Vesa Korhonen

10:15 - 10:40 Jerome Thevenot, University of Oulu: Medical applications of thermal imaging

10:40 - 11:05 Teemu Myllylä, University of Oulu: Towards continuous monitoring of the glymphatic

system of the human brain

11:05 - 11:30 Ilya Skovorodkin, University of Oulu: Challenges and solutions in high resolution 4D

confocal imaging of multicellular embryonic tissues and organoids

11:30 – 12:30 Lunch and Poster Session

Session 3, Chair: Prof. Seppo Vainio

12:30 - 12:55 Ilkka Pölönen, University of Jyväskylä, Finland: Hyperspectral imaging for diagnosis of

skin cancer

12:55 - 13:20 Saad Akram, University of Oulu: Cell tracking via proposals generation and selection

13:20 - 13:45 Aleksei Tiulpin, University of Oulu: Deep learning for medical image analysis

13:45 - 14:10 Ronald Sroka, Laser-Forschungslabor, University Hospital Munich, Germany:

Fluorescence diagnostics and photodynamic therapy (Keynote)

14:10 - 14:30 Sponsored Coffee and Posters Session 4, Chairs: Ms. Aleksandra Zienkiewicz, Mr. Lukasz Surazynski

Session 5, Chair: Prof. Vesa Kiviniemi

14:30 - 14:55 Tatiana Novikova, Ecole Polytechnique, Palaiseau, France: Polarimetry for biomedical

research (Invited)

14:55 - 15:20 Anne Heikkinen, University of Oulu: Collagen XIII deficiency in mice models

congenital myasthenic syndrome type 19

15:20 - 15:45 Timo Tuovinen, University of Oulu: CV mapping of fMRI data in different brain

diseases

16:00 Bus transportation from University to Conference Dinner place

17:00 - 22:00 Conference dinner

22:00 Bus transportation Conference Dinner place to City center and University

[10]

PROGRAM

DAY 2 (2.6.2017)

Place: Tellus Arena, Linnanmaa, University of Oulu

Session 1, Chair: Dr. Matti Kinnunen

09:00 - 09:30 Jussi Hiltunen, VTT - Technical Research Center of Finland: Raman measurements

09:30 - 10:00 Matti Kinnunen, University of Oulu: Optical tweezers: principles and selected

applications

10:00 - 10:30 Ronald Sroka, Laser-Forschungslabor, University Hospital Munich, Germany: Laser-

assisted stone fragmentation

10:30 - 11:00 Katja Lefevre, Specim, Finland: Hyperspectral imaging - from science to industrial daily

use

11:00 - 11:30 Pawel Wierzba, Gdansk University of Technology, Poland: Selected applications of

polarization interferometry (Invited)

11:30 - 12:00 Marianne Hiltunen, VTT - Technical Research Center of Finland: Integrated optics

(Invited)

Lunch 12:00 – 13:00

Session 2, Chairs: Dr. Alexey Popov, Dr. Teemu Myllylä

13:00 - 13:15 Ivan Bratchenko, Samara National Research University, Russia: Towards virtual biopsy.

Multimodal spectroscopy for cancer detection

13:15 - 13:30 Tianmiao Zhang, ITMO University, Russia: Wavelet analysis for Terahertz time-domain

spectroscopy

13:30 - 13:45 Stephan Stroebl, Laserforschungslabor, LIFE-Centre, Universitätsklinikum Grosshadern,

Germany: In vitro investigations on fluorescence behavior of urinary and kidney calculi

13:45 - 14:00 Cristine Calil Kores, KTH - Royal Institute of Technology, Sweden: Spectral

investigation of ultranarrow-linewidth distributed-feedback resonators below laser

threshold

14:00 - 14:15 Ehsanul Hoque Apu, University of Oulu: Light microscopy and algorithm based

mathematics to analyze cancer cell movement using 3D in vitro matrix models

14:15 - 14:30 Daria Majchrowicz, Gdansk University of Technology, Poland: Nanodiamond structures

for fiber optics devices

14:30 - 14:45 Abba Saleh, Tampere University of Technology, Finland: Short-range supercontinuum

LIDAR for temperature profiling

Break 14:45 – 15:00

Session 3, Workshop, Chairs: Ms. Aleksandra Zienkiewicz, Mr. Lukasz Surazynski

15:00 - 16:00 From Academy to industry - what to expect?

16:00 - 17:30 SPIE/OSA chapters meeting

17:30 - 19:00 University and Lab tours

[11]

PROGRAM

DAY 3 (3.6.2017)

Place: Tellus Arena, Linnanmaa, University of Oulu

Session 1, Chair: Dr. Alexander Bykov

09:00 - 09:30 Janis Spigulis, University of Latvia: Hyperspectral and multispectral skin imaging

(Invited)

09:30 - 10:00 Irina Zavestovskaya, National Research Nucler University MEPhI, Russia: Nanovector

drug delivery (Keynote)

10:00 - 10:30 Mikhail Kirillin, Institute of Applied Physics of Russian Academy of Sciences, Russia:

Advancing optical coherence tomography with numerical techniques (Invited)

10:30 - 11:00 Andrey Dunaev, Orel State University named after I.S. Turgenev, Russia: Methods and

means of optical non-invasive diagnostics of hemodynamics and metabolic activity of

human tissues (Invited)

11:00 - 11:30 Mikhail Khodzitsky, ITMO University, Russia: Terahertz photonics for biomedical

applications (Invited)

11:30 - 12:00 Nikolay Brandt, Moscow State University, Russia: Raman and ATR FTIR spectroscopy

in the study of chemical reaction rates (Invited)

Lunch 12:00 – 13:00

Session 2, Chair: Dr. Mikhail Khodzitsky

13:00 - 13:30 Ghassan Jabbour, University of Ottawa, Canada: Room temperture long lifetime

phosphorescence from organic exciplex

13:30 - 13:45 Oleg Miakinin, Samara National Research University, Russia: Toward virtual biopsy.

Cancer Imaging

13:45 - 14:00 Sviatoslav Gusev, ITMO University, Russia: Influence of glucose concentration on

blood optical properties in THz frequency range

14:00 - 14:15 Daniel Gomon, ITMO University, Russia: Physical principles of design of metamaterial

absorber based on electrical ring resonators

Break 14:15 – 14:30

Session 3, Chair: Dr. Oleg Miakinin

14:30 - 14:45 Mariia Borovkova, University of Oulu: Study of birefringence alterations during optical

clearing of biological tissues

14:45 - 15:00 Alexey Trofimov, ITMO University, Russia: Simulations of terahertz wire-grid

polarizers on substrate

15:00 - 15:15 Atiqul Mazumder, University of Oulu: Imaging of extracellular nanovesicle exosomes in

mental health

15:15 - 15:30 Dhananjay Patel, S.V. National Institute of Technology, India: Mitigating transmitter

non-linearity and fiber impairments in Radio over Fiber technology

Session 4, Chairs: Dr. Alexey Popov, Prof. Igor Meglinski

16:00 - 16:15 Best oral & poster awards and Concluding remarks

18:00 - 20:00 City tour

[12]

POSTERS

1 Anton Sdobnov Laser Speckle Contrast Imaging of a transition from non-

ergodic to ergodic light scattering

University of

Oulu

2 Tatiana Avsievich Optical tweezers: probing effect of nanoparticles on red

blood cells aggregation

University of

Oulu

3 Motahareh

Peyvasteh

Meat freshness inspection by visible and near-infrared

spectroscopy

University of

Oulu

4 Prateek Singh Raman spectroscopy of human sweat components University of

Oulu

5 Yunyun Dai Dynamic tuning of graphene plasmonic resonances by

ultraviolet light

Aalto

University

6 Yadong Wang Graphene enabled Active Optical Fiber Devices Aalto

University

6 Yadong Wang Graphene enabled Active Optical Fiber Devices Aalto

University

7

Michał

Ziemczonok, Maria

Baczewska

Tomographic phase microscope for study of mouse

fibroblast

Warsaw

University of

Technology

8 Alexandr

Grebenchukov

Narrowband optically tunable terahertz filter based on

graphene for biomedical applications

ITMO

University

9 Cherniadev

Aleksandr Terahertz dielectric lens for super-resolution images

ITMO

University

10 Maxim Masyukov Polarazing properties of metasurface based on chiral

unit cell in THz frequency range

ITMO

University

11 Egor Litvinov Epsilon-near-zero copper-dielectric composite for

terahertz frequency range

ITMO

University

12 Petr Demchenko Control the optical properties of phosphate glass with

CdSe quantum dots in terahertz frequency range

ITMO

University

13 Anna

Tyumchenkova

Research studies of aging changes of hyaline cartilage

surface by using Raman-scattering spectroscopy

Samara

National

Research

University

14 Oleg Frolov Optical surface evaluation of bone implants during its

processing

Samara

National

Research

University

15 Polina

Shalkovskaya

Using of Raman spectroscopy method in comparative

spectral analysis of the surface of aortal valves of the

hert of baranes before and in process of their

decellularization

Samara

National

Research

University

16 Lyudmila Shamina Lab-on-a-chip system for the analysis of biofluids

Samara

National

Research

University

[13]

POSTERS

17 Anastasia Lykina Projection on latent structures method for analysis of

blood plasma Raman spectra

Samara

National

Research

University

18 Igor Kozlov Possibilities of Doppler spectrum analysis of laser

radiation received from hand skin during functional tests

Orel State

University

named after I.S.

Turgenev

19 Evgeniya Seryogina Fluorescence spectroscopy usage possibilities for the

laboratory rats metabolism evaluation

Orel State

University

named after I.S.

Turgenev

20 Viktor Dremin Analytical model to describe fluorescence spectra of

human skin

Orel State

University

named after I.S.

Turgenev

21 Irina Makovik Laser diagnostics method for evaluation of properties of

blood flow oscillations in rheumatologic patients

Orel State

University

named after I.S.

Turgenev

22 Ksenia Kandurova

Possibilities of application of fluorescence spectroscopy

in minimally invasive surgery for analysis of abdominal

cavity organs pathological processes

Orel State

University

named after I.S.

Turgenev

23 Elena Zharkikh

Application of adaptive wavelet-analysis for the study of

cutaneous blood flow oscillations in patients with

diabetes mellitus

Orel State

University

named after I.S.

Turgenev

24 Olga Stelmashchuk Imaging of rhodamine-loaded capsules distribution in

vivo by fluorescence spectroscopy’

Orеl State

University

named after I.S.

Turgenev

25 Anna Babashkina Determination of Doppler angle based on the carrier

spectrum broadening

Tambov State

Technical

University

26 Oleksandr Olar Stokes correlometry of polarization inhomogeneous

object fields

Yuriy

Fedkovych

Chernivtsi

National

University

27 Vitali

Ghoghoberidze Density Of quantum States In periodical Structures

Tbilisi State

University

28 Emily Plorina Non-invasive evaluation of skin pathologies by RGB

autofluorescence imaging

University of

Latvia

29 Nina Verdel

Quantitative assessment of skin composition and

scattering properties in human volunteers using

photothermal radiometry and diffuse reflectance

spectroscopy in vivo

Jožef Stefan

Institute

[14]

Oral section

[15]

SqCC/Y1 (ZB)

Tra

ject

ory

plo

t

Figure 3

SqCC/Y1 (BB)SqCC/Y1 (FL)SqCC/Y1 (Vect Ct)

LIGHT MICROSCOPY & ALGORITHM BASED MATHEMATICS TO ANALYZE CANCER CELL

MOVEMENT USING 3D IN VITRO MATRIX MODELS

Ehsanul Hoque Apu*1,3, Saad Akram2, Hong Wan3 and Tuula Salo1,4 1Cancer and Translational Medicine Research Unit, University of Oulu, Oulu, Finland

2Dept. of Computer Science and Engineering, University of Oulu, Oulu, Finland

3Queen Mary University of London, London, UK

4Department of Oral and Maxillofacial Diseases, University of Helsinki, Helsinki, Finland

*Contact: ehsanul.hoqueapu@oulu.fi

Keywords: light microscopy, live cell imaging, 3D matrix models, image analysis

Tumor microenvironment (TME) consists of the non-transformed stromal elements within the tumor. Invasion of

carcinomas is defined as passing the basement membrane and infiltration into the underlying interstitial tissue by

malignant tumor cells. Cancer cell invasion has been traditionally studied in three dimensional (3D) models composed of

rat or mouse extracellular matrix (ECM) proteins such as type I collagen and Matrigel. In order to study In Vitro 3D

squamous cell carcinoma (SCC) invasion, our research group developed a human derived TME model (Myoma

organotypic) using uterine leiomyoma tissue [1]. We have also developed a processed, gelatinous leiomyoma matrix

named Myogel, according to the method for the preparation of mouse Engelbreth Holm Swarm (EHS) tumor derived

Matrigel [2]. Our results suggest that the novel Myogel is practical and even superior to the commercial Matrigel.

In this study we aimed to validate the quality of our Novel product Myogel, is suitable and even better than Matrigel or

collagen for fast and reproducible testing of cancer cell-TME interaction via In Vitro invasion assays using microscopy

techniques and image analysis methods. Thus four stable cell lines in oral buccal squamous cell carcinoma (SCC)

SqCC/Y1 cell lines were generated for this purpose.

The four cell lines are Vector controlled cell (Vect Ct), overexpressed full length (FL) and two mutant cell lines (BB &

ZB). These cell lines were previously used to analyze the quantitative differences in 2D cell migration after live cell

imaging using IncuCyte system [Figure]. 3D Sandwich technique was used to observe the SqCC/Y1 cell movement under

ECM culture conditions in both monoculture and co-culture (with Fibroblasts). Images were taken with Olympus cellSens

live-cell imaging system for 18 hours. Huygens Professional software was used for image processing and deconvolution

of the time lapse images prior to analysis. With the help of MATLAB algorithm we analyzed the Sandwich experiment

data to study the speed, size, shape (eccentricity/ roundness), travelled distances of the SqCC/Y1 cells and their nuclei in

different TME-ECM conditions. An algorithm based mathematical method was developed to quantify the movement of

cells.

The average SCC cell speed, distances in Myogel was more than their average speed in collagen and Matrigel. Their

distances, size & shape (eccentricity/ roundness) were also different. The nuclei and cellular shape were decreased in

Myogel, which suggests there were more cell movement than in Matrigel. There were variations observed among the four

cell lines.

We found that our new product, Myogel mimics the native human TME better. It allows long term live cell imaging and

better image acquisition. It is suitable, stable & even better than Matrigel or collagen for fast and reproducible testing of

cancer cell TME interaction in 3D experiment methods.

1. S. Nurmenniemi et al, “A novel organotypic model mimics the tumor microenvironment”,

American Journal of Pa thology, 175(3): 1281–1291, 2009

2. T. Salo et al, “A novel human leiomyoma tissue derived matrix for cell culture studies”, BMC Cancer, 15: 981, 2015

Figure:

Trajectory plots

show migration

patterns of 30

cells from four

different cell

lines.

[16]

STUDY OF BIREFRINGENCE ALTERATIONS DURING OPTICAL CLEARING OF BIOLOGICAL

TISSUES

Mariia Borovkova*, Alexander Bykov, Alexey Popov, and Igor Meglinski

Optoelectronics Unit, Faculty of Information Technology and Electrical Engineering, University of Oulu, Oulu, Finland

* Contact: Mariia.Borovkova@oulu.fi

Keywords: polarimetry, Stokes parameters, birefringence, optical clearing

Recently the use of optical technology for biomedical research and health care has been growing explosively. A variety

of new methods are being applied to medical research showing a great potential in diagnostics, monitoring and therapy.

We present the results of an experimental study on alterations of the birefringence properties of biological tissue during

the optical clearing. Optical clearing is a well-known technique commonly used for reduction of scattering of biological

tissues with a primary aim to increase penetration depth and contrast of optical imaging techniques [1]. Chicken skin was

chosen for the experiments due to its proved birefringence properties [2] and good susceptibility to the optical clearing

[1].

In the experimental system, the laser diode (640 nm, 40 mW) produced linearly polarized light that altered by a quarter-

wave plate into the right-hand circularly polarized light. During the experiments, the right-hand circularly polarized light

was directed at 55o towards a sample of chicken skin turned upside down and immersed in glycerol. The dish containing

the sample was located on a translation stage, which was moving back and forth along a 1 cm line with a 100 µm step for

180 minutes. At each step, the polarization properties of the light scattered back from the chicken skin sample were

analyzed by a Stokes vector polarimeter. Fig.1 shows typical alterations of Stokes parameters (a) and Stokes vectors on

the Poincare sphere (c) measured during the 3-hour optical clearing experiment. Besides, in order to characterize the

birefringence properties of the tissue, phase retardation is presented (see Fig.1-b).

Fig.1 a – measured Stokes parameters, b – Phase retardation, c – Stokes vectors on the Poincare sphere (dark to light

colormap corresponds to the time flow) of the radiation scattered back from the chicken skin sample versus time of the

experiment.

As one can see Q and U Stokes parameters do not indicate any significant changes, whereas the V parameter gradually

goes down under the influence of the optical clearing (see Fig.1-a). The same trend is observed on the Poincare sphere.

The results are well agreed with the results of alternative studies [3]. Fig.1-b shows typical phase retardation between two

orthogonal polarization components during the experiment. Average time retardation is 40 deg. for this experiment.

According to our results, during the process of optical clearing, the V Stokes component shows the most noticeable down

trend due to scattering reduction and birefringence alterations in the chicken skin sample during the optical clearing. The

described polarization-based modality allows for fundamental study of properties of biological tissues. In framework of

further studies, we plan to investigate potential applications of this approach for optical diagnosis of skin, as well as its

applicability for the food and skin care industries.

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under

the Marie Skłodowska-Curie grant agreement No 713606.

1. Tuchin V. V. (2006) Optical clearing of tissues and blood. – Bellingham: SPIE Press.

2. Matoltsy, A. G. (1969). Keratinization of the avian epidermis: an ultrastructural study of the newborn chick skin. Journal of Ultrastructure Research, 29(5-6), 438-458.

3. Macdonald, C., Meglinski, I. (2011). Backscattering of circular polarized light from a disperse random medium influenced by optical clearing. Laser Physics Letters, 8(4), 324-328.

mailto:Mariia.Borovkova@oulu.fi

[17]

RAMAN AND ATR FTIR SPECTROSCOPY IN THE STUDY OF CHEMICAL REACTION RATES

I.A. Balakhnina, N.N. Brandt*, A.Yu. Chikishev, A.A. Mankova, I.G. Shpachenko

Faculty of Physics and International Laser Center, Lomonosov Moscow State University,

Moscow, 119991 Russia *Contact: brandt-nn@yandex.ru

Keywords: Raman spectroscopy, FTIR, ATR FTIR, chemical reactions, reaction rate, chemical kinetics,

enzymes, functional activity

We apply Raman and ATR FTIR spectroscopy for the study of the kinetics of chemical reactions. We

have shown that the reaction rates of chemical reactions can be determined using Raman spectroscopy

by measuring time dependence of Raman spectra of reaction mixture. Reaction of alkaline hydrolysis

of ethyl acetate is considered as an example. The results are in good agreement with available

literature data. Reaction kinetics is represented as a plot of the intensity of a Raman band versus time.

Fitting of experimental kinetics with analytical solution of kinetic equations allows one to determine

reaction rates. Besides, we measure temperature dependence of reaction rates and thus calculate

activation energy. Raman spectroscopy was also used to analyze the enzymatic reaction kinetics

(hydrolysis of 2,4-dinitrophenyl acetate catalyzed by α-chymotrypsin).

The kinetics obtained for the same reaction using Raman and ATR FTIR spectroscopy are

often different. The reason for that is the specific interaction of the components of reaction solution

with the surface of ATR crystal. We found the spectral changes occurring with time for several pure

substances and chemically stable mixtures applied on attenuated total reflection surface.

[18]

TOWARD VIRTUAL BIOPSY. MULTIMODAL SPECTROSCOPY FOR CANCER DETECTION

Bratchenko I.A.*1, Artemyev D.N.1, Myakinin O.O.1, Khristoforova Yu.A.1, Moryatov A.A.2,

Kozlov S.V.2 and Zakharov V.P.1 1Department of laser and biotechnical systems, Samara University, Samara, Russia

2Department of oncology, Samara State Medical University, Samara, Russia

*Contact: iabratchenko@gmail.com

Keywords: cancer, optical biopsy, Raman spectroscopy, autofluorescence, OCT, hyperspectral imaging

Problem of increased incidence of cancer is known worldwide. For instance yearly in Russia more than 550

thousand cases of cancer are registered and the largest amount of deaths caused by cancer are due to skin and

lung cancers. Moreover about 13 – 15 % of deaths in Russia are caused by cancers [1]. It is necessary to find

a new ways of early cancer detection. Optical methods may be very useful for tissues analysis and tumor type

determination. They allow for finding a chemical composition of tested tissues in vivo and in real time mode

[2]. In our study complex investigation of malignant tumors diagnosis was performed involving combined

optical coherence tomography (OCT), Raman spectroscopy (RS), autofluorescence (AF) analysis and

hyperspectral imaging. Combined setup was used for common skin and lung malignant tumors analysis and

for precise tissue morphology visualization. For example, the differentiation of skin melanomas and basal cell

carcinomas (BCCs) was demonstrated based on combined analysis of RS and AF spectra stimulated by visible

and NIR lasers. A number of spectroscopic criteria utilizing information about alteration of melanin,

porphyrins, flavins, lipids, and collagen content in tumor with a comparison to healthy skin were proposed [3].

It was shown that the accuracy of cancerous tissues classification reaches more than 97% for a combined

multimodal algorithm and PCA data analysis (Figure 1), while the accuracy determined separately for each

modality does not exceed 79%. In general AF allows for scanning large tissue areas and detecting abnormal

formations, while imaging techniques helps to analyze tumor topology and invasion area. Adding RS analysis

allows for precise determination of biomechanical composition of tumor and exact tumor type determination

as a result.

Fig. 1: Melanomas and BCC classification on the phase plane with joint VIS AF monitoring of porphyrins composition

and relative content of porphyrins, lipids and flavins.

1. P.E. Goss et al., “Challenges to effective cancer control in China, India, and Russia,” Lancet Oncol. 15, 489–538,

2014.

2. T.D. Wang and J. Van Dam, “Optical Biopsy: A New Frontier in Endoscopic Detection and Diagnosis,” Clin

Gastroenterol Hepatol, 2(9), 744–753, 2004.

3. I.A. Bratchenko et al., “Combined Raman and autofluorescence ex vivo diagnostics of skin cancer in near-infrared

and visible regions” Journal of Biomedical Optics, 22 (2), 027005, 2017.

[19]

LASER-INDUCED SURFACE GRAPHITIZATION OF DIAMOND FOR METAMATERIAL

FABRICATION

Margarita Dezhkina*1, Maxim Komlenok1, 2, Sergey Lebedev2, Gennady Komandin2,

Vitaly Konov1, 2

1National Research Nuclear University MEPhI, Moscow 2A.M. Prokhorov General Physics Institute RAS, Moscow

*Contact: m.a.dezhkina@gmail.com

Keywords: laser, graphitization, diamond, metamaterial

Nowadays laser technology is widely used in microstructuring of diamond for fabrication of new optic [1] and

electronic [2] elements. For example, Kononenko et al. applied laser technique for relief formation on the

diamond surface, and as a result diffraction optical element was fabricated [3]. Such element can be used for

control of powerful radiation due to transparency and high thermal conductivity of diamond. It should be

mentioned that thin graphitized layer, which absorbed part of the incident radiation, remained on the diamond

surface after its processing. In this connection graphitic material was removed from diamond surface. But if

one does not remove graphitized layer then conductor-dielectric compound can be created. These elements in

which new optical properties appear due to the periodic alternation of conductive and dielectric structures are

called metamaterials.

In this work, periodic structure of graphitized paths with length of 4200, width of 15 and period of 30 μm was

created on the diamond surface. For this purpose, excimer KrF-laser (CL 7100, τ = 20 ns, λ = 248 nm) was

used. Figure 1 shows the microscope image of the sample after laser processing. Optical properties of sample

were investigated in the frequency range of 900-1200 GHz. Electromagnetic waves with two type of

polarization passed through the sample during the experiment. Figure 2 illustrates the results of measurements.

It was demonstrated that this structure can filter THz-radiation with certain polarization. Optical element was

transparent for radiation with one type polarization, and transmittance decreased in case of waves with another

type of polarization. The result demonstrates the possibility of using laser-induced graphitization for

fabrication of metamaterials with different optical properties by varying geometry of conductive paths.

Fig. 1: Periodic graphitized lines on the diamond surface, Fig. 2: Transmittance spectra of graphitized grid on the

fabricated by means of irradiation with excimer laser diamond substrate

M. Dezhkina acknowledges funding from National Research Nuclear University MEPhI. This work was

supported by the Russian Science Foundation (project “Carbon photonics”). M. Komlenok acknowledges

funding from Russian Foundation for Basic Research grant 16-32-60179.

[20]

PHYSICAL PRINCIPLES OF DESIGN OF METAMATERIAL ABSORBER BASED ON

ELECTRICAL RING RESONATORS

Daniel Gomon*1, Egor Sedykh1, Kirill Zaitsev2, Mikhail Khodzitsky1

1ITMO University, Saint Petersburg, 197101, Russia

2Bauman Moskow State Technical University, Moscow, 105005, Russia

*Contact: GomonDA89@ya.ru

Keywords: Metamaterials, Terahertz spectroscopy, Time-resolved Spectroscopy

Metamaterial devices for terahertz (THz) frequency range have been a subject of close attention for the last decade [1–

4]. A reason behind this interest is a need for materials with strong absorption in terahertz frequency range for such

applications as terahertz sensing, hyperspectral imaging and screening [5]. Such materials could be realized on base of

metasurfaces with resonant elements as electrical ring resonators (ERR). The aim of this work is analysis of physical

processes occurring in such structures for development of ideal absorber in THz frequency range. For investigation of

physical processes influences of absorber layers thicknesses, ERR geometric parameters and incidence radiation

polarization angles on reflection spectrum were investigated. After theoretical optimization metamaterial absorber with

absorptivity peak of 99.8% was fabricated.

Fig. 1: The influence of the polyimide SU-8 layer thickness on the resonant peak absorptivity

Fig. 2: The reflection coefficient of the experimental metamaterial absorber samples for polarization angles = 0 (solid

curve) and = 90 (dotted curve)

1. N. I. Landy, S. Sajuyigbe, J. J. Mock, D. Smith, and W. J. Padilla, “Perfect Metamaterial Absorber,” Phys. Rev. Lett. 100,

pp. 207402-1–4, 2008

2. X. Shen, T. J. Cui, Junming Zhao, H. F. Ma, W. X. Jiang, and H. Li, “Polarization-independent wide-angle triple-band

metamaterial absorber,” Optics Express 19(10), pp. 9401–9407, 2011

3. J. Grant, Y. Ma, S. Saha, A. Khalid, and D. R. S. Cumming, “Polarization insensitive, broadband terahertz metamaterial

absorber,” Opt. Lett. 36(17), pp. 3476–3478, 2011

4. B. Wang, X. Zhai, G. Wang, W. Huang, and L. Wang, “A novel dualband terahertz metamaterial absorber for a sensor

application,” Journal of Applied Physics 117(1), pp. 014504, 2015

5. S. A. Kuznetsov, A. G. Paulish, A. V. Gelfand, P. A. Lazorskiy, and V. N. Fedorinin, “Matrix structure of metamaterial

absorbers for multispectral terahertz imaging,” Progress In Electromagnetics Research 122, pp. 93–103, 2012

[21]

INFLUENCE OF GLUCOSE CONCENTRATION ON BLOOD OPTICAL PROPERTIES IN THZ

FREQUENCY RANGE

S.I. Gusev*1, P.S. Demchenko1, O.P. Cherkasova2, V.I. Fedorov1,3, and M.K. Khodzitsky1 1Photonics and Optical Information Technology Department, ITMO University, St.Petersburg,, Russia

2Institute of Laser Physics of SB RAS, Novosibirsk, Russia

3Automation and Computer Engineering Department, Novosibirsk State Technical University,

Novosibirsk, Russia

*Contact: mail@gusev-spb.ru

Keywords: Spectroscopy, terahertz; Blood or tissue constituent monitoring.

Diabetes mellitus is a group of metabolic diseases characterized by hyperglycemia resulting from

defects in insulin secretion, insulin action, or both [1]. There is a direct relationship between the level

of glucose in the blood of patients with diabetes and the probability of developing complications of

the disease [2]. Accurate and efficient assessment of blood glucose concentration is critical in clinical

management of many pathological conditions in human population.

One of the most important benefits of terahertz spectroscopy methods is the possibility of non-

invasive analysis of biological samples [3]. Transmission mode of spectroscopy is common way for

collecting data about easy extractable media. On the one hand transmission mode of medium analysis

provides accurate results, but can be unsuitable for completely non-invasive investigation of

biological tissues and fluids [4, 5]. On the other hand, reflection mode of spectroscopy cannot be used

for direct blood optical measurement due to the location of blood below the surface of the human

body. Moreover, THz reflected signal considerably weakened due to the water contained in the skin

layer. Despite this, capillar blood located in fingers' nail beds may be investigated through the nails

in the reflection mode.

In this work, optical properties of blood with different glucose concentrations were obtained using

THz time-domain spectroscopy. Based on it, dependencies of glucose concentrations C glucose with

complex refractive index (ηreal and ηimag), absorption coefficient (α), penetration depth (L) complex

permittivity (εreal and εimag) real were presented. These data have been received for the first time in

the THz frequency range. It will be helpful in the process of creating a spectroscopic method of blood

glucose measuring.

1. “Classification and diagnosis of diabetes,” Diabetes Care, 38, S8, 2014.

2. Ceriello, A. and Colagiuri, S., “International diabetes federation guideline for management of postmeal glucose: a

review of recommendations,” Diabetic Medicine, 25(10), 115, 2008.

3. Pickwell, E., Cole, B., Fitzgerald, A., Pepper, M., and Wallace, V., “In vivo study of human skin using pulsed terahertz

radiation”, Physics in Medicine and Biology, 49(9), 1595, 2004.

4. Gusev, S., Borovkova, M., Strepitov, M., and Khodzitsky, M., “Blood optical properties at various glucose level values

in THz frequency range,” in [European Conferences on Biomedical Optics], 95372A–95372A, International Society for

Optics and Photonics (2015).

5. Gusev, S., Balbekin, N., Sedykh, E., Kononova, Y. A., Litvinenko, E., Goryachuk, A., Begaeva, V., Babenko, A. Y.,

Grineva, E., and Khodzitsky, M., “Influence of creatinine and triglycerides concentrations on blood optical properties of

diabetics in THz frequency range,” Journal of Physics: Conference Series, 735(1), 012088, 2016.

[22]

ADVANCING OPTICAL COHERENCE TOMOGRAPHY WITH NUMERICAL TECHNIQUES

Mikhail Kirillin

Institute of Applied Physics, Russian Academy of Sciences, 46 Ulyanov St., Nizhny Novgorod, Russia, 603950

Contact: mkirillin@yandex.ru

Keywords: optical coherence tomography, Monte Carlo simulations, histogram analysis

Optical coherence tomography (OCT) is a modern imaging modality actively penetrating both into medical

practice and industrial applications. Being based on principles of low coherence interferometry OCT technique

benefits from non-invasive/non-destructive imaging with spatial resolution down to units of microns at depths

up to several mm. In medical practice OCT is widely employed for tissue diagnosing and treatment monitoring.

Besides common application in ophthalmology, OCT is employed dermatology, stomatology, gynecology,

vascular diagnostics etc. In material science OCT is used for production and processing control. Many OCT

applications may be advanced by employment of numerical techniques that allow to predict the abilities of

OCT systems for particular tasks and quantify diagnostics results by images processing and segmentation.

This paper overviews the approaches to numerical simulations and processing of OCT images that enhance

the technique performance. Simulation of OCT images is based on a model of propagation of probing radiation

in the studied medium accounting for detection conditions. Both analytical and numerical approaches can be

employed. Unfortunately, application of analytical models is limited to simple object geometries while

numerical techniques provide much wider abilities. One of the most efficient techniques for simulation of light

propagation in tissues is Monte Carlo technique allowing to trace individual photon trajectories and study the

details of signal and image formation. In this presentation particular Monte Carlo applications allowing to

simulate the OCT systems that do not exist yet, separate multiple scattering contribution in the entire signal

and develop techniques for image processing are considered.

Next class of numerical techniques employed in OCT enhancement is image quantification. These techniques

consist in recovering different quantitative parameters, such as object optical properties, speckle statistics

parameters or a customized score aimed for particular OCT application. The presentation reviews recent

achievement in OCT image scoring that allowed to increase the diagnostic accuracy of the technique in several

clinical applications. Another class of numerical methods widely employed in OCT is image segmentation.

Different segmentation techniques are based on pixel intensity characterization or similarity principles.

To conclude, numerical techniques allows both for prediction of perspective OCT systems potential and

enhancing diagnostic accuracy of existing OCT inspection protocols.

The study is supported by Russian Science Foundation (project # 17-15-01264).

mailto:mkirillin@yandex.ru

[23]

OPTICAL TWEEZERS: PRINCIPLES AND SELECTED APPLICATIONS

Matti Kinnunen

Faculty of Information Technology and Electrical Engineering, University of Oulu, Oulu, Finland

Contact: matti.kinnunen@oulu.fi

Keywords: optical tweezers, calibration, red blood cell, elastic light scattering

Optical tweezers (OT) allows for non-contact trapping and manipulating single micro- and nano-sized particles

using tightly focused laser beam. An important feature of OT is that they can measure forces ranging from

several pN to almost hundred pN. Such forces characterize the interactions between biological cells and

macromolecules. Multi-channel laser tweezers allow simultaneous trapping and manipulating with multiple

particles (or cells). It makes the OT approach a powerful tool for assessing the mechanisms of biological

structures’ interaction at single cell level [1,2,3].

In order to make quantitative measurements, OT must be calibrated. Calibration of optical tweezers means

determining the trap stiffness and trapping force magnitude for certain intensities of the laser beam.

Consequently, the force exerted onto an object as a function of the measured displacement of the object in the

trap is then known. OT can be also used to keep the cells in place, when applying additional instrumentation.

As an example, elastic light scattering distributions can be measured from trapped cells [4].

In this presentation, basics of optical tweezers as well as basic calibration methods are presented. Then the

usability of the optical tweezers to study light-matter interactions at the single particle and cell level as well as

between several particles/cells is summarized. As another application area, OT is used to study RBC interaction

mechanics.

1. K. Lee, M. Kinnunen, M. Khokhlova, E. Lyubin, A. Priezzhev, I. Meglinski, and A. Fedyanin, “Optical tweezers study of red blood cell aggregation and disaggregation in plasma and protein solutions,” Journal of Biomedical

Optics, 21(3), 035001, 2016.

2. K. Lee, M. Kinnunen, A. V. Danilina, A. V. Priezzhev, V.D. Ustinov, I. Meglinski, S. Shin"Characterization of shear stress preventing the red blood cells from aggregation at the individual cells level and in whole blood sample",

Journal of Biomechanics, 49(7), PP. 1021–1026, 2016.

3. K. Lee, A. V. Danilina, M. Kinnunen, I. Meglinski and A. V. Priezzhev, ” Probing the Red Blood Cells Aggregating Force with Optical Tweezers,” Journal of Selected Topics in Quantum Electronics, 22(3), 7000106, 2016.

4. M. Kinnunen, A. Karmenyan, “Overview of single-cell elastic light scattering techniques,” Journal of Biomedical Optics, 20(5), 051040, 2015.

mailto:matti.kinnunen@oulu.fi

[24]

SPECTRAL INVESTIGATION OF ULTRANARROW-LINEWIDTH DISTRIBUTED-FEEDBACK

RESONATORS BELOW LASER THRESHOLD

Cristine C. Kores*1, Dimitri Geskus1, Nur Ismail1, Meindert Dijkstra2, Edward H. Bernhardi1,3, and

Markus Pollnau1 1Materials and Nano Physics, Department of Applied Physics, School of Engineering Sciences, KTH – Royal Institute of

Technology, Stockholm, Sweden 2Optical Sciences, MESA+ Institute, University of Twente, Enschede, The Netherlands

3visiting scientist

*Contact: cck@kth.se

Keywords: distributed-feedback resonators, narrow linewidth, coupled mode theory.

Distributed-feedback lasers (DFB) have the unique characteristic of allowing ultranarrow-linewidth laser emission, which can be exploited for sensor applications [1], for it constitutes a high resolution, real time, label- free sensing platform [2].

In this work, we characterize the spectral behaviour of a DFB laser resonator [3] below its laser threshold. The investigated device is an amorphous Al2O3 channel waveguide of 1 cm length, 2.5 1.0 µm2 lateral cross section, and an Yb3+ concentration of 4.37 1020 cm-3, with a corrugated homogeneous

Bragg grating of strength ~ 8.5 inscribed into its SiO2 top cladding of 100 nm thickness. The device shows a resonance inside the reflection band due to an adiabatic /4 phase shift. The Yb3+ ions are excited with increasing levels of pump power at 980 nm up to the point where the device reaches its laser threshold, and the full-width-at-half-maximum linewidth of the Lorentzian-shaped resonance near 1029 nm, corresponding to a single longitudinal mode, is measured by use of a scanning narrow-linewidth laser source. The increasing gain elongates the photon decay time out of the resonator and, consequently, narrows the spectral line shape of the resonance. The linewidth decrease of the resonance from u in the unpumped case, i.e., including losses due to absorption by Yb3+ ions in their ground state, to L in the pumped case can be calculated from the equation L = u –cg/2 [4], in which g is the relative gain per unit length and c is the speed of light in the active medium. Gain measurements were carried out by use of a pump-probe technique to obtain the value of g as a function of pump power. The linewidth as a function of pump power is calculated from the experimentally measured values of the relative gain per unit length.

The measured linewidth of the resonance peak narrows as a function of pump power. The observed shift in the peak wavelength is due to heat dissipated by the absorbed pump power, which changes the refractive index of the material and causes a physical expansion of the grating. The results of the linewidth measurement and the linewidth expected from the measured gain are discussed.

1. E. H. Bernhardi, K. O. van der Werf, A. J. F. Hollink, K. Wörhoff, R. M. de Ridder, V. Subramaniam, and M. Pollnau, “Intra-laser-cavity microparticle sensing with a dual-wavelength distributed-feedback laser”, Laser

Photonics Rev. 7 (4), pp. 589-595, 2013.

2. S.V. Pham, M. Dijkstra, A.J.F. Hollink, L.J. Kauppinen, R.M. de Ridder, M. Pollnau, P.V. Lambeck, H.J.W.M. Hoekstra, “On-chip bulk-index concentration and direct, label-free protein sensing utilizing an optical grated-

waveguide cavity”, Sens. Actuator B: Chem. 174, pp. 602-608, 2012.

3. E. H. Bernhardi, M. R. H. Khan, C. G. H. Roeloffzen, H. A. G. M. van Wolferen, K. Wörhoff, R. M. de Ridder, and M. Pollnau, “Photonic generation of stable microwave signals from a dual-wavelength Al2O3:Yb3+

distributed-feedback waveguide laser”, Opt. Lett. 37 (2), pp. 181-183, 2012.

4. M. Eichhorn and M. Pollnau, “Spectroscopic foundations of lasers: Spontaneous emission into a resonator mode”, IEEE J. Sel. Top. Quantum Electron. 21 (1), 9000216, 2015.

mailto:cck@kth.se

[25]

REMOTE PHOTOPLETHYSMOGRAPHY SYSTEM FOR CONTACTLESS REGIONAL

ANESTHESIA MONITORING IN OPERATING ROOM

M. Lange*1, U. Rubins1 and A. Miscuks2 1University of Latvia, Institute of Atomic physics and Spectroscopy, Riga, Latvia

2Hospital of Traumatology and Orthopedics, Riga, Latvia

*Contact: marta.lange.rtu@gmail.com

Keywords: remote photoplethysmography, regional anesthesia, skin perfusion

In orthopedic surgeries when delivering the anesthetic it is often not so easy to actually recognize the moment when the

regional anesthesia (RA) has become effective and the surgeon can begin to cut. So far there are a few subjective methods

widely used, like the temperature or touch test. We propose a method that is non-invasive and can give measurable

evaluation in the moment when the anesthetic has become effective.

A simple and inexpensive remote photoplethysmography (rPPG) system for monitoring the effectiveness of regional

anesthesia was developed and tested in the operating room (OR). The system involves surgical lamp as light source,

compact video camera and computer with custom developed software. Data from eight patients were processed and the

effectiveness of regional anesthesia was calculated.[1, 2]

Fig. 1: The principle of rPPG technique

Local anesthetic affects the sympathetic vascular tone by resulting in vasodilation and subsequent rising of

microcirculation intensity in the palm skin. This leads to the increase of amplitude of fast-varying rPPG signal detected

by our system. The effectiveness of RA was evaluated in 8 clinical cases in Hospital of Traumatology and Orthopedics,

Riga, Latvia.

The perfusion response slightly differs across the patients, depending on the heterogeneity of the group of patients and

the variance of anesthetic procedure. The PPGA maximum value (100%) was found empirically: from the subject having

best RA effect, and 50% of PPGA maximum value was suggested as the threshold of a successful anesthesia. The

effectiveness of RA was expressed by PPGA signal maxima/minima ratio, which is different from subject to subject.

The results showed that the standard surgical lamp can be used as a light source together with the high dynamic range

camera for remote monitoring of skin microcirculation. In future this kind of a quantitative contactless imaging tool can

become a useful medical device for anesthesiologists in ORs.

1. M. Kumar, A. Veeraraghavan, and A. Sabharwal. DistancePPG: Robust non-contact vital signs monitoring using a

camera. Biomed. Opt. Express, vol. 6, no. 5, p. 1565, May 2015.

2. U. Rubins, J. Spigulis, A. Miscuks. Photoplethysmography imaging algorithm for continuous monitoring of regional

anesthesia. ESTIMedia'16 Proc. of 14th ACM/IEEE Symposium on Embedded Systems for Real-Time Multimedia, pp.

67-71 (2016).

[26]

NANODIAMOND STRUCTURES FOR FIBER OPTICS DEVICES

Daria Majchrowicz*, Paweł Wierzba, Małgorzata Jędrzejewska-Szczerska

Gdańsk University of Technology, Faculty of Electronics, Telecommunications and Informatics, Department of

Metrology and Optoelectronics, Gabriela Narutowicza Street 11/12, 80-233 Gdańsk, Poland

*Contact: dmajchrowicz@eti.pg.gda.pl

Keywords: low-coherence interferometer, nanodiamond thin film, fiber optic, reflective layers

Nanodiamond is one of new materials that stimulate the progress in optoelectronic devices. One of the most promising

Nanodiamond classes is nanocrystalline diamond films. They have remarkable properties like optical transparency in a

broad wavelength range, chemical stability and biocompatibility. Their conductivity and refractive index can be modified

by boron doping. For instance, increasing boron level will decrease transmittance of thin diamond film also influence

refractive index.

A low-coherence sensor using interferometer with diamond reflective layer was designed and built. Its performance was

investigated for selected diamond films. The diamond films can be used in low-coherence interferometric sensors as a

protective coating or reflective layer. The diamond films were synthesized using Microwave Plasma Enhanced Chemical

Vapour Deposition (µPE CVD), which allows us to tune their properties as: thickness, grain size, roughness, chemical

composition and surface morphology by changing the process conditions. Measurements were performed using two

superluminescent diodes (SLD) with wavelengths of 1300 mm and 1550 mm. Detection of the measured signal was

performed using an optical spectrum analyzer (Ando AQ6319). All devices were connected with single-mode

telecommunications fiber (SMF-28).

The preliminary results show that deposition parameters have influence on the optical properties of investigated films.

The boron-doped film used as the reflective surface allows us to achieve very good visibility of the signal for the much

smaller cavity lengths than those of conventional sensors employing other reflective layers.

[27]

IMAGING OF EXTRACELLULAR NANO VESICLES EXOSOMES IN MENTAL HEALTH

Atiqul Haq Mazumder*1, Seppo Vainio2 and Juha Veijola3 1Doctoral Student, Department of Biochemistry and Molecular Medicine, University of Oulu, Finland.

2Professor, Biocenter Oulu, Department of Biochemistry and Molecular Medicine, University of Oulu, Finland.

3Professor, Department of Psychiatry, University of Oulu, Finland

*Contact: atiqul.mazumder@oulu.fi

Keywords: exosomes, mental health, nano vesicles

Exosomes (EXs) are nano sized (30-100 nm) extracellular vesicles released by the mammalian cells. They cargo wealth

of key regulatory to close but also distant cells representing a newly identified humoral system.

EXs form by inward bulging of the walls of late endosomes entrapping cocurrently the cargo molecules to them. The

multi vesicular bodies serve to release EXs through the cell membranes. EXs are widely distributed in different types of

biological fluids including breast milk, saliva, urine, blood and cerebrospinal fluid. They can traverse the blood brain

barriers and can be distributed even to the very distant parts of the body to carry their cargo. Functions: EXs contain

several types of molecular factors such as micro-ribonucleic acids (miRNAs), messenger ribonucleic acids (mRNAs),

genomic deoxyribonucleic acids (gDNAs), proteins, lipids and metabolites. They spread several kinds of infections,

cancers and diseases to nearby or distant tissues. EXs have some causative roles in Alzheimer's disease, Parkinson's

disease, Prion disease, schizophrenia and bipolar disorders. Prospects in mental health: EXs serve likely as valuable

predictive, diagnostic and prognostic markers for mental health disorders. In addition they can be used to transport f.ex.

nano-magnets and nano-gold to develop novel in vivo imaging capasity for brain imaging via functional Magnetic

Resonance Imaging (f-MRI). They can be used as therapeutic carriers for example of edited RNA spesies for brain

transport from brain to peripheral tissues and vice versa. Conclusion: The exosomes have a proven diagnostic and

prognostic role as well as promising therapeutic role in teranostics and cargo of mRNAs, stem cells, cytokines and other

metabolites to target tissues such as the brain. They offer great avenues for the imaging of neuropsychiatric

malfunctioning and associated novel therapeutics.

1. Kalra H, Gregor P, Drummen GPC, Mathivanan S. Focus on extracellular vesicles: introducing the next small big

thing. International Journal of Molecular Science 2016 Feb;17(2):170.

2. Stoicea N, Du A, Lakis DC, Tipton C, Arias-Morales CE, Bergese SD. The MiRNA journey from theory to practice

as a CNS biomarker. Frontières of Genetics. 2016 Feb 9;7:11.

3. Zappulli V, Friis KP, Fitzpatrick Z, Maguire CA, Breakefield XO. Extracellular vesicles and intercellular

communication within the nervous system. The Journal of Clinical Investigation. 2016 Apr;126(4):1198–1207.

[28]

MITIGATING TRANSMITTER NON-LINEARITY AND FIBER IMPAIRMENTS IN RADIO OVER

FIBER TECHNOLOGY

Dhananjay Patel* and Upena Dalal

Electronics Department, Sardar Vallabhbhai National Institute of Technology, Surat, Gujarat, India

*Contact: dhananjaypatel76@yahoo.in

Keywords: Radio over Fiber (RoF), Single Sideband Generation (SSB), Single and Multimode fiber,

Orthogonal Frequency Division Multiplexing (OFDM)

Single mode fibers (SMF) are typically used in Wide Area Networks (WAN), Metropolitan Area Networks (MAN) and

also find applications in Radio over Fiber (RoF) architectures supporting data transmission in Fiber to the Home (FTTH),

Remote Antenna Units (RAUs), in-building networks etc [1]. Multi-mode fibers (MMFs) with low cost, ease of

installation and low maintenance are predominantly (85% to 90%) deployed in in-building networks providing data access

in local area networks (LANs). The transmission of millimeter wave signals through the SMF in WAN and MAN, along

with the reuse of MMF in in-building networks will not levy fiber reinstallation cost. The transmission of the millimeter

waves experiences signal impairments due to the transmitter non-linearity and modal dispersion of the MMF [2]. The

MMF exhibiting large modal dispersion limits the bandwidth-length product of the fiber. The second and higher-order

harmonics present in the optical signal fall within the system bandwidth. The power of these harmonics is proportional to

the non-linearity of the transmitter and the modal dispersion of the MMF. In this work, a mathematical model is developed

for Second-order Harmonic Distortion (HD2) generated due to non-linearity of the transmitter and chromatic - modal

dispersion of the SMF-MMF optic link. The model consists of a Mach Zehnder Modulator (MZM) that generates two m-

QAM OFDM SSB signals based on phase shift of the hybrid coupler (90° and 120°) [3].

Figure: Setup for the generation of both SSB

modulation techniques

Figure. Effect of HD2 due to MZM non-linearity and

modal dispersion over different MMF length

Our results show that the SSB signal with 120° hybrid coupler has suppresses the higher-order harmonics and makes the

system more robust against the HD2 in the SMF-MMF optic link [4]. This provides better system performance against

the MZM non-linearity, the chromatic/modal dispersion of the SMF -MMF optic link. In future we plan to develop

bidirectional architecture of RoF system to increase the data rate and which can overcome all the losses of the fiber

indicated above and also the Rayleigh Backscattering associated with bidirectional transmission.

1. Beas, J.; Castanon, G.; Aldaya, I.; Aragon-Zavala, A.; Campuzano, G., "Millimeter-Wave Frequency Radio over Fiber

Systems: A Survey," in IEEE Communications Surveys & Tutorials, vol.15, no.4, pp.1593-1619, Fourth Quarter 2013

2. Gasulla and J. Capmany, "Transfer function of multimode fiber links using an electric field propagation model:

Application to Radio over Fibre Systems," Opt. Express 14, 9051-9070 (2006)

3. Dhananjay Patel, Vinay Kumar Singh & U. D. Dalal (2016): Assessment of Fiber Chromatic Dispersion Based on

Elimination of Second-Order Harmonics in Optical OFDM Single Sideband Modulation Using Mach Zehnder

Modulator, Fiber and Integrated Optics, 35.4 (2016) 181–195

4. Dhananjay Patel, Vinay Kumar Singh, U.D. Dalal, Analysis of second order harmonic distortion due to transmitter

non-linearity and chromatic and modal dispersion of optical OFDM SSB modulated signals in SMF-MMF

fiber links, Optics Communication, 383 (2016) 294–303.

[29]

SHORT-RANGE SUPERCONTINUUM LIDAR FOR TEMPERATURE PROFILING

Antti Aalto1, Tommi Mikkonen1, Abba U. Saleh1,2 and Juha Toivonen1

1Laboratory of Photonics, Tampere University of Technology, Tampere, Finland 2 Valmet Technologies Oy, Energy Services, Lentokentankatu 11, Tampere, Finland

*Contact: abba.saleh@tut.fi

Keywords: supercontinuum, LIDAR, remote-sensing

LIDAR (Light Detection and Ranging) is a remote-sensing technique based on collection of back scattered

electromagnetic radiation form a target point. The interaction of this radiation with atmospheric gases and

aerosol particles pave way for the measurement of various atmospheric variables, such as temperature,

pressure, humidity, trace gases, etc. [1]. Although the LIDAR technique has been consistently used to measure

atmospheric observables, the technique is typically limited to one specie at a time. However, supercontinuum

sources have raised the hope for simultaneous measurement of multiple species, via provision of extremely

broad spectrum, which covers the absorption bands of the entire molecules/compounds under investigation

[2].

Herein, a new technique is developed for temperature mapping in thermal devices, like combustion power

plants, using a supercontinuum-based LIDAR. The device is designed to measure temperature profile inside

the furnace using one opening. The technique is based on differential absorption between three wavelength

bands. Fig. 1 shows the schematic of the device, where supercontinuum light pulses are guided into a furnace

comprising of various particles and gases such as COx, NOx, H2O. Aerosol particles scatter the incoming light,

the back-scattered lights are collected and individual wavelength bands are detected and their corresponding

intensities are recorded as a function time. Fig. 2 shows H2O transmittance with a typical 14% concentration

and 10 m interaction length, where variation in transmittance with temperature is observed. By selecting and

comparing certain wavelength bands, temperature profile within the thermal device can be determined based

on the differential absorption at these wavelength bands. Our initial laboratory scale measurements

demonstrate temperature measurement accuracy of 10 o C in the range from 700 o C to 1000 o C.

Moreover, molecular number density or concentration can be measured using the same technique. The

uniqueness of this technique is that 2D and 3D temperature profiles can be obtained by sending multiple pulse

sequences while varying their direction of incidence using simple optical components such as mirrors.

1. Weitkamp, Claus, ed. Lidar: range-resolved optical remote sensing of the atmosphere. Vol. 102. Springer

Science & Business, 2006.

2. Méjean, G., et al. "Towards a supercontinuum-based infrared LIDAR." Applied Physics B: Lasers and

Optics 77, 357 – 359 (2003).

Fig. 1: Schematic for the temperature mapping technique.

Fig. 2: Transmittance of H2O with 14% concentration at

700 o C and 1200 o C respectively.

mailto:abba.saleh@tut.fi

[30]

FABRICATION OF NOVEL ORGANIC AND INORGANIC THIN FILM TRANSISTORS AND

EXPLORATION OF SUBGAP DENSITY OF STATES

M. R. Shijeesh and M. K. Jayaraj* 1 Nanophotonic and Optoelectronic Devices Laboratory, Department of Physics,

Cochin University of Science and Technology, Cochin 682022, Kerala, India

*Contact: mkj@cusat.ac.in

Keywords: thin film transistor, organic, inorganic, density of states

A thin-film transistor (TFT) is a special kind of field-effect transistor made by depositing thin films of an active

semiconductor layer as well as the dielectric layer and metallic contacts over a non-conducting substrate [1-4]. We

fabricated both organic and inorganic thin film transistors and the charge transport of transistors was studied from the

temperature dependent transistor characteristics. N,N′-Dioctyl-3,4,9,10-perylenedicarboximide (n-type) and pentacene (p

type) small molecules were used as the channel materials for organic TFTs. Amorphous zinc tin oxide (n-type) and

copper oxide (p-type) were used as the channel materials for fabricating inorganic TFTs. In order to study the distribution

of the trap states, we have examined the temperature dependent transfer characteristics of transistors in the temperature

range between 300 K and 360 K. The activation energy is determined from the measured data with a linear regression of

Arrheneus plot drawn between ln ID vs 1000/T for each gate voltage. The localized states induced by defects or impurities

are distributed in the band gap and a study of those distributions of localised states in the band gap leads to exploration

of charge transport mechanism in the semiconductor [5]. The knowledge about the charge transport mechanism and

subgap DOS is essential not only for the fundamental understanding of the device operation but for the improving of

device performances.

.

Fig. 1: (a) The output and (b) transfer characteristics pentacene TFT. (c) Density-of-states in the gap of pentacene

1. E. Fortunato, P. Barquinha, and R. Martins, Adv. Mater. 24, 2945 (2012)

2. J.S. Park, H. Kim, and I.D. Kim, J. Electroceramics 32, 117 (2014)

3. P. Barquinha, L. Pereira, G. Goncalves, R. Martins, and E. Fortunato, J. Electrochem. Soc. 156, H161 (2009)

4. Yu-Chun Chen, Ting-Chang Chang, Hung-Wei Li, Wan-Fang Chung, Chang-Pei Wu, Shih-Ching Chen, Jin Lu, Yi-Hsien Chen and Ya-Hsiang Tai, Appl. Phys. Lett, 100, 262908 (2012)

5. J. Puigdollers, M. Della Pirriera, A. Marsal, A. Orpella, S. Cheylan, C. Voz, and R. Alcubilla, Thin Solid Films 517, 6271 (2009)

[31]

IN-VITRO INVESTIGATIONS ON FLUORESCENCE BEHAVIOR OF URINARY AND KIDNEY

CALCULI

Stephan Ströbl*1, Max Eisel1, Thomas Pongratz1, Stefan Stöberl1,

Frank Strittmatter2, Ronald Sroka1 1 Laserforschungslabor, LIFE-Zentrum, University Hospital Munich, Germany

2 Department of Urology, University Hospital Munich, Germany

*Contact: Stephan.stroebl@med.lmu.de

Keywords: Urology, Urinary Stones, Fluorescence, Laser lithotripsy, Stone clearance

For ureteroscopic Ho:YAG laser lithotripsy laser light of 2100nm is applied onto a urinary calculus, hence energy is

applied to the stone surface, resulting in fragmentation by photothermal and acoustic mechanisms [1]. The major operation

failure could be traced back to an incomplete stone clearance and due to that to a higher risk of relapse [2]. The major

problem of identification is based upon a low contrast difference between the surrounding tissue and the urinary stone

under white light emission, thus small fragments remain untreated. The aim of this project is to circumvent this concern

by taking the advantage of auto-fluorescence of the urinary calculi. The fluorescence behavior of urinary stones was first

used for a safety feature to control the laser energy during lithotripsy [3].

Urinary stones harvested from patients were spectral analyzed in in-vitro

measurements. Excitation-emission-matrices (EEM) were established, clarifying the

wavelength dependent fluorescence behavior of the stones. This confirmed the

selection of green-light excitation, as it was used in previous experiments. Figure 1

illustrates the fluorescence of a urinary stone under green light excitation. To get a

deeper physical understanding of the fluorescence, the EEM data was correlated with

the stone composition gained from Raman spectroscopy. From the correlation

between the stone composition and its fluorescence behavior, the possibility might

arise to characterize the stone’s composition from its characteristic fluorescence

spectrum, which will be part of future studies.

The high relapse rate due to incomplete stone clearance could also be reduced by

considering the fragmentation process itself. Observations show, that this process is

highly influenced by a change in the application laser parameters (energy per pulse, pulse duration, pulse frequency).

Therefore, methods were developed to quantify different physical properties, such as fragmentation time, dusting ratio

and stone movement. The influence of different laser parameters on those quantities was investigated and compared

between each other. An optimized laser setting might remove the targeted stone without producing a significant amount

of small remaining fragments.

It had been illustrated in six large retrospective studies, that the natural cumulative recurrence rate of renal stones is

around 14% at 1 year, 35% at 5 years, and 52% at 10 years [4]. Also recent studies couldn’t show an improvement on

relapse numbers [5]. These examples showed the need for the development of fluorescence assisted clearance detection.

In combination with an optimization process with regard to the laser parameters, a clearance scan at the end of each

lithotripsy for remaining urinary stone fragments might guarantee a fragment free environment in the treated area.

1. H.W. Kang, “Dependence of Calculus Retropulsion on Pulse Duration During Ho:YAG Laser Lithotripsy”, Lasers in

Surgery and Medicine 38, pp. 762-772, 2006

2. J.L. Figueiredo, C.C. Passerotti, “A Novel Method of Imaging Calcium Urolithiasis Using Fluorescence”, The Journal

of Urology 179, pp. 1610–1614, 2008

3. S.P. Dretler, “Review: Urolithiasis – Electrohydaulic and Laser Lithotripsy”, Journal of Endourology 7, Number 5,

1993

4. J. Uribarri, “The First Kidney Stone”, Annals of Internal Medicine 111, pp. 1006-1009, 1989

5. D.A. Rebuck, “The natural history of renal stone fragments following ureteroscopy”, Urology 77, pp. 564-568, 2011

Figure 1: Fluorescence Image of an

urinary stone after excitation at

wavelength between 500 and 570 nm.

mailto:Stephan.stroebl@med.lmu.de

[32]

SIMULATIONS OF TERAHERTZ WIRE-GRID POLARIZERS ON SUBSTRATE

Alexey D. Trofimov*, Valentin S. Chebotarev and Mikhail K. Khodzitsky

Terahertz Biomedicine Lab., ITMO University, St. Petersburg, Russia

*Contact: Alexey.D.Trofimov@gmail.com

Keywords: polarization-selective devices

The terahertz (THz) industry requires the development of new effective optical elements, including THz polarizers. THz

polarizers are required for polarization-sensitive material studies, characterizing polarization of different THz sources,

polarization dependence of THz detectors and other purposes. Powerful THz sources are still a big challenge for the

industry, which requires THz polarizers to have low losses along with effective extinction of undesired polarization.

Several approaches for developing THz polarizers exist. Free-standing wire-grid polarizers can have high extinction ratio

and low losses, but are fragile and hard to manufacture [1]. Robust polarizers with high extinction ratio exist but usually

have considerable losses [2]. One of the approaches suggested for developing an effective THz polarizer is development

of metal wire-grid polarizers on a substrate. A wire-grid provides high extinction ratio while a substrate facilitates easier

manufacturing and enhances robustness of a polarizer; however, it may increase losses. Substrate-based THz polarizers

can also be stacked in a multi-layered configuration thus increasing both the overall extinction coefficient and the overall

losses [3]. Different fabrication technologies vary in parameters they provide such as spatial resolution of resulting

structures and have different financial costs. For this reason, it is important to know how sizes of the fabricated structures

affect performance of the polarizer.

In this work one-layered and multilayered polarizers for terahertz radiation made of metal grating on a substrate are

studied via numerical simulations. The dependencies of extinction ratio and transmission losses on wire grid dimensions

(period, thickness, fill factor), metal type and number of layers of a polarizer have been obtained. The results of the study

can be used for development of an optimal THz polarizer design with acceptable losses and within limits of the chosen

fabrication technology.

Fig. 1: Extinction coefficient for several layers of wire-grid on a silicon substrate

1. Costley A.E. et. al. ”Free-standing fine-wire grids: Their manufacture, performance, and use at millimeter and

submillimeter wavelengths,” J. Opt. Soc. Am. 67, № 7, pp. 979–981, 1977

2. C.-F. Hsieh et. al. ”Polarizing terahertz waves with nematic liquid crystals,” Opt. Lett. 33, pp. 1174-1176, 2008

3. Huang Z. et al. ”Ultra-high extinction tri-layer thin-film wire-grid THz polarizer,” 40th International Conference on

Infrared, Millimeter, and Terahertz waves (IRMMW-THz). IEEE, p. 1, 2015

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mailto:Alexey.D.Trofimov@gmail.com

[33]

WAVELET ANALYSIS FOR TERAHERTZ TIME DOMAIN SPECTROSCOPY

Tianmiao Zhang* and Mikhail K. Khodzinsky

Terahertz Biomedical Laboratory, ITMO University, St. Petersburg, Russia

*Contact: tmzhang91@gmail.com

Keywords: wavelets, Fourier transforms, terahertz, time domain spectroscopy

Terahertz has been widely used in many fields and areas [1]. One of the most popular applications is Terahertz Time

Domain Spectroscopy (TDS). TDS can be used to detect properties of biomedical tissue or industrial products [1]. A TDS

system contains a terahertz source, a measured sample and an optical system. A terahertz pulse is generated from the

source and then incident into a sample. The sample reflects, transmits and absorbs the incoming terahertz pulse. By

detecting the spectrum of the reflected or transmitted wave, which can be considered as a TDS signal, some terahertz

properties of the sample can be revealed, such as complex permittivity, complex reflective index and absorption

coefficient.

To get the spectrum of a TDS signal, the most usual method is Fourier transform. Fourier-transform converts a signal

from time domain to frequency domain. As is well-known, noise spectrums appear with signal spectrums. To increase

the signal-noise-ratio, filters must be used, and the cutoff frequencies of filters are determined by the result of Fourier

transform. The disadvantage of Fourier transform is that from the spectrum we can’t figure out when the noise appeared

and how long it existed directly from the spectrum. If filters are not used properly, some useful information may be filtered

with noises.

In order to filter a TDS signal without losing important information, wavelet-transform can be used. Wavelet transform

is a signal processing method that uses a set of wavelet functions to approximate a signal. Each set of wavelet functions

is formed by changing the scale and position on the time axis of a mother wavelet. Compared with Fourier transform,

wavelet transform contains information in time domain and frequency domain, so the approximation can be done more

accurately. In Fig. 1 a sample mother wavelet and its Fourier-transform are shown.

From the spectrum, we can consider the mother wavelet as a bandpass filter. Because of this, we don’t need to do Fourier

transform first then determine properties of filters, but directly filter the signal by wavelet. To filter noise out of a signal

by wavelet, Mallat algorithm is usually used. In Mallat algorithm, a signal is filtered with a high-pass filter and low-pass

filter, and the cutoff frequencies of these filters are associated with mother wavelets [2]. Mallat algorithm is shown as

below [3]:

Fig. 1. Daubechies wavelet (db4) and its spectrum Fig. 2. Mallat

algorithm

To filter a signal ideally, there are several options we need to determine: mother wavelet, decomposition level and

threshold. There are many criterions that can be used to value each option [4,5]. In our work, with the help of these

criterions, for each TDS signal we chose an optimal set of options. The result shows that with optimal set of options, a

noised signal can be denoised directly by using wavelet, and the effectiveness of wavelet filtration is remarkable.

1. Joo-Hiuk Son, “Terahertz Biomedical Science and Technology” (CRC Press, 2014)

2. Stephane Mallat, Sifen Zhong, “Characterization of Signals from Multiscale Edges” IEEE transactions on pattern

analysis and machine intelligence, Vol.14, No. 4, pp. 710–732, 1992

3. 小波分析及应用, available at https://wenku.baidu.com/view/4ed6ea3031126edb6f1a10e5.html, cited on 2017-04-08

4. Kirill I Zaytsev and el, “An approach for automatic construction of the wavelet-domain de-noising procedure for THz

pulsed spectroscopy signal processing” Journal of Physics: Conference Series, Vol.486, No. 012034, pp. 1–9, 2014

5. Jihong Pei, Weixin Xie, “Optimal wavelet analysis for THz