lesson05 [modo de compatibilidad] - unamfarah/optomechanics/clases/lesson05/lesson05.pdf ·...
Post on 12-Mar-2020
2 Views
Preview:
TRANSCRIPT
Clase 05:Mechanical Supports
Dr. Alejandro Farah
OptoMechanics
Instituto de Astronomía, UNAM
Posgrado de Ingeniería, UNAM
content…
2. Mechanical Supports
Understanding the influence of mechanical support systems
in the optical components.
2.1.3 Definición de fase, velocidad de fase, superposición de ondas y
velocidad de grupo.
2.1.4 Principio de Huygens.
Posgrado de Ingeniería, UNAM
…first of all…a few words…
spatial stability,
position and rotation,
failure,
human error
…
Posgrado de Ingeniería, UNAM
The phase of an oscillation or wave is the fraction of a complete cycle
corresponding to an offset in the displacement from a specified reference
point at time t = 0.
Phase is a frequency domain or Fourier transform domain concept, and as
such, can be readily understood in terms of simple harmonic motion.
2.1.3 Definition of phase, phase velocity, superposition of waves and
group velocity.
Posgrado de Ingeniería, UNAM
Assumption: light is a harmonic wave (sinusoid)
Phase speed of a wave: is the rate at which the phase of the wave
propagates in space.
The phase speed is given in terms of the wavelength λ (lambda) and
period T as
2.1.3 Definition of phase, phase velocity, superposition of waves and
group velocity.
Posgrado de Ingeniería, UNAM
Phase difference
Equal phase (or cophased)
Out of phase
2.1.3 Definition of phase, phase velocity, superposition of waves and
group velocity.
Posgrado de Ingeniería, UNAM
2.1.3 Definición de fase, velocidad de fase, superposición de ondas y
velocidad de grupo.
If two interacting waves meet at a point where they are in antiphase,
then destructive interference will occur.
Posgrado de Ingeniería, UNAM
It is common for waves of electromagnetic (light, RF), acoustic (sound) or
other energy to become superposed in their transmission medium.
2.1.3 Definition of phase, phase velocity, superposition of waves and
group velocity.
Posgrado de Ingeniería, UNAM
2.1.3 Definition of phase, phase velocity, superposition of waves and
group velocity.
When that happens, the phase difference determines whether they reinforce or
weaken each other. Complete cancellation is possible for waves with equal
amplitudes.
The principle of superposition of waves states that the resultant displacement at a
point is equal to the vector sum of the
displacements of different waves at that
point.
Posgrado de Ingeniería, UNAM
2.1.3 Definition of phase, phase velocity, superposition of waves and
group velocity.
Chromatic interference is seen in sea foam, which is
made out of plankton. It is an example of the naturally
occurring interference.
Posgrado de Ingeniería, UNAM
2.1.4 Huygen´s principle.
It recognizes that each point of an advancing wave front is in fact the
center of a fresh disturbance and the source of a new train of waves; and
that the advancing wave as a whole may be regarded as the sum of all
the secondary waves arising from points in the medium already
traversed.
Posgrado de Ingeniería, UNAM
HomeWork: 2.2
- Talking about teslescopes and astronomical instruments:
i) How does interferometry work?
ii) Is it possible for everyone to do optical interferometry?
- What is a ray trace software? And mention at least 3 commercial
softwares to do that.
Posgrado de Ingeniería, UNAM
P R O Y E C T O de O P T O M E C Á N I C A
Objetivo:
Realizar el diseño conceptual y preliminar de los soportes
optomecánicos para el instrumento astronómico
RATIR.
Metas particulares:
- Proponer métodos de soporte de componentes ópticos a nivel conceptual.
- Evaluar el diseño de todos los componentes mecánicos de soporte
propuestos para el proyecto.
- Realizar el cálculo de esfuerzos, desplazamientos y rotaciones de los
diferentes sistemas desarrollados.
- Comparar el desempeño calculado con los requerimientos y especificaciones
del instrumento.
top related