Zielgruppe
Target group: Physics and Electrical Engineering students
The students will:
- get familiar with Fourier description of imaging through aberrated optical systems and random media,
- understand the description of aberrations through Zernike modes,
- learn how to analytically compute the effects of turbulence on various optical observables such as image/beam motion, temporal power spectra, Zernike modes, scintillation, etc.,
- understand the effect of noise on various quantities and metrics pertinent to the design of adaptive optical systems,
- understand the advantages and disadvantages of various schemes for wavefront sensing and correction,
- learn how to simulate and design simple adaptive optics systems.
Content
Adaptive optics is a technology of correcting the effect of atmospheric turbulence on images of space objects and on laser beams propagating through random and highly aberrated media such as turbulence, tissue, and the inside of the human eye, to name just a few applications. The course will familiarize the students with theoretical basics of light propagation through random media, principles of wavefront sensing and reconstruction, as well as wavefront correction with deformable mirrors. The students will also receive solid introduction to statistical optics, the Kolmogorov theory of turbulence, practical aspects of turbulence simulation and modelling of adaptive optics.
- 1. Theory of turbulence (covariances, structure functions, power spectra, inertial range, dimensional argument of Kolmogorov)
- 2. Fourier optics (point-spread function, modulation transfer function)
- 3. Statistical optics (characteristic function, probability density function)
- 4. Sources and description of aberrations (Zernike polynomials, orthogonality, Marechal criterion)
- 5. Adaptive optics systems (open- and closed-loop systems, error budgets, tip-tilt correction)
- 6. Wavefront sensing (Shack-Hartmann wavefront sensor, wavefront reconstruction, wavefront-sensorless AO)
- 7. Wavefront correction (tip-tilt mirrors, deformable mirrors, piezoelectric effect, microelectromechanical systems, electrostatic actuation)
- 8. Simulation of adaptive optical systems (analytic vs. end-to-end modelling)
- 9. Propagation of laser beams through atmospheric turbulence (Gaussian beams, Rytov theory, scintillation index, beam wander)
- 10. Modelling of free-space optical communication systems (aperture averaging, mean signal-to-noise ratio, false-alarm rate and fade probability, bit error-rate)
Module grade calculation
The module grade is the grade of the oral exam.
Prerequisites
It is recommended that the students first complete the module Optical Engineering [M-ETIT-100456] (currently offered as "Optical Engineering and Machine Vision") or Fundamentals of Optics and Photonics [M-PHYS-101927] before they enroll for this course.
Recommendation
Basic knowledge of statistics.
Literature
- Robert K. Tyson, Principles of Adaptive Optics, CRC Press
- Michael C. Roggemann, Byron M. Welsh, Imaging through Turbulence, CRC Press
