Optique de Fourier [T7PS524M]

Optique de Fourier [T7PS524M]

En pratique

Nature
Elément constitutif
Volume horaire de TP
2
Volume horaire de TD
16
Volume horaire de CM
20
Volume horaire de travail personnel
45
Langue d'enseignement
Français

Description du contenu de l'enseignement

The aim of the course is to present the basic concepts and formalism of Fourier optics, i.e. to show how bi-dimensional Fourier analysis and linear system theory allow to describe free-space light propagation and diffraction-limited coherent and incoherent imaging. Many fields of optics can be addressed with the Fourier optics formalism, such as optical signal processing, imaging system analysis, and holography.

Organisation

Modalités d'organisation et de suivi

Part I: Formalism and basics

  1. Free-space propagation as a 2D invariant linear system
  2. Space-time analogy between diffraction and dispersion
  3. The ideal thin lens as a 2D-Fourier-transform operato

Part II: Spatial filtering and analogue optical information processing

  1. Spatial filtering setup: the 4f configuration
  2. Analogue optical information processing with amplitude objects
  3. Optical imaging of phase objects

Part III: Frequency analysis of the performance of optical imaging systems

  1. Introduction to frequency analysis of optical imaging systems
  2. Frequency response of diffraction-limited optical imaging systems
  3. Case study: Microscope with Köhler illumination

 

Informations pédagogiques

Compétences à acquérir

After completing the course, the student will be able to:

  •  understand the concept of spatial frequency spectrum (or 2D-Fourier spectrum) of a diffractive object;
  •  understand the description of free-space propagation as a 2D linear system, and recall the expression of its impulse response and its transfer function;
  •  calculate the field distribution after propagation over a given distance in free space in the framework of the Fresnel approximation (three approaches);
  •  explain why and how a thin lens can be used to reproduce the Fraunhofer diffraction conditions;
  •  describe the 4f configuration and explain the principle of the following coherent optical filtering processes:
    •  "cleaning up" of a laser beam profile;
    •  raster detection or elimination;
    •  dark field method and phase contrast method;
  • explain the difference between coherent and incoherent illumination in an optical imaging system;
  • use the 2D linear-system analysis tools (impulse response, transfer function) to evaluate the performance of a diffraction-limited optical imaging system.

 

Pré-requis recommandés

  •  Propagation of a plane or spherical wave in a linear homogeneous isotropic medium
  •  Scalar diffraction theory
  •  Fourier analysis
  •  Analysis of linear systems

 

Bibliographie, lectures recommandées

  • J. W. Goodman, “Introduction to Fourier optics”, Freeman (2017, 4th ed.).
  • W. Lauterborn, T. Kurz, and M. Wiesenfeldt, “Coherent optics”, Springer (2003, 2nd ed.).
  • B. H. Kolner, “Space-time duality and the theory of temporal imaging”, IEEE J. Quant. Electron. 30, 1951 (1994).

 

Dernière modification : ven, 08/01/2021 - 17:38