laser beam mode and polarization analyzers

8/7/2019 Laser Beam Mode and Polarization Analyzers

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LASER BEAM MODES

& POLARIZATION

ANALYZERS

Birhan UUZ

[email protected]


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Outline

Fundamental Properties of LASER,

Laser Beam Modes,

Laser Beam Mode Analyzers,

Polarization,

Polarization Analyzers.


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Coherent ,

Monochromic,

Directional,

Polarized.

http://80.251.40.59/eng.ankara.edu.tr/hsari/ders-optoelektronik.htm

Partial ReflectorTotal Reflector


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Laser Mode

-Longitudinal mode

-Transverse mode (Beam Mode)

Transverse

mode

Longitudinal

mode



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Longitudinal Mode

-Oscillation of electric field of light over time.



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Transverse Mode (Beam Mode)

Concave Lenses

-Electric field distribution on perpendicular direction of propagation of light.


Gaussian Distribution Hermite- Gaussian Distribution


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Laser Beam Mode Analyzers

Non-Electronic

Burn Spots On Thermal Paper

Acrylic Mode Burns

Electronic

Camera-Based Analyzer

Scanning Slit Analyzer

Scanning Knife-Edge Analyzer

The CVI Melles Griot Technical Guide, Gaussian Beam Optic, 2009


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Laser Beam AnalyzersNon-Electronic

Burn Spots On Thermal Paper

Briallant Nanosecond Laser System / Burn Spot On Thermal Paper at 1064 nm

15 cm 30 cm 120 cm 7,8 m

+ Easily and cheap.

-Without quantitative measurements

-Dynamic range of 3;

unburned, burned and over burned.


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Laser Beam Analyzers

+ Can see generally structure.

-Toxic fumes occurs,

-Very rough quantitative measurements,

- Only shows average over time of laser beam.

http://www.ophiropt.com/user_files/laser/beam_profilers/modecheckPre.pdf

Non-Electronic

Acrylic Mode Burns


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Laser Beam AnalyzersElectronic


http://www.newport.com/High-Resolution-Laser-Beam-Profiler/608093/1033/catalog.aspx

+ Acquire Real-time data and display,+ Quantitative measurements,+ Fast laser diagnosis.

- Delicate equipment,-Expensive.-Limited by pixel size between 5-10 m


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Laser Beam AnalyzerElectronic


Ankara University, Optical Materials Research Group, omag.ankara.edu.tr


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Laser Beam Analyzer

+ Quantitative measurements,

+ One image every few seconds.

- Signal to noise ratio is low,

- Signal must be like a Gaussian.

Thorlabs Beam Beam Analyzing Software, Operation Manual, 2011

Electronic



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Laser Beam Analyzer


Electronic



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Laser Beam Analyzer

The CVI Melles Griot Technical Guide, Fundamental of Beam Profiling ,2009

Electronic

Scanning Knife-Edge Analyzer

+ Can measure beam diameter up to 1 m,

+ Quantitative measurements,

+ One image every few seconds,

+ Signal to noise ratio is high.

- Signal must be like a Gaussian.


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Polarization

J. A. Woollam Co., Inc., Tutorial, www.jawoollam.com/tutorial_2.html

Light can be described as an electromagnetic wave traveling throughspace.


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Polarization

J. A. Woollam Co., Inc., Tutorial, www.jawoollam.com/tutorial_2.html


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Polarization Analyzer

J. A. Woollam Co., Inc., A Short Course in Ellipsometry, Chapter 2


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References


The CVIMelles Griot Technical Guide, Gaussian Beam Optic, 2009

Quantel Briallant Nanosecond Laser System

http://www.ophiropt.com/user_files/laser/beam_profilers/modecheckPre.pdfhttp://www.newport.com/High-Resolution-Laser-Beam-

Profiler/608093/1033/catalog.aspx


The CVI Melles Griot Technical Guide, Fundamental of Beam Profiling ,2009

J. A. Woollam Co., Inc., Tutorial,www.jawoollam.com/tutorial_2.html

J. A. Woollam Co., Inc., A Short Course in Ellipsometry, Chapter 2


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Thank You.

[email protected]

laser beam mode and polarization analyzers

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