Physical Optics Modeling With FRED

Physical optics modeling requires propagating optical wave fields from a specific radiometric source through complex systems of apertures and reflective or refractive optical components, or even complete instruments or devices, usually to a focal plane or sensor. The model must accurately include the interference and diffraction effects allowed by the polarization and coherence characteristics of both the initial optical wave field and the components and media through which it passes.


Photon Engineering’s advanced tutorial on Physical Optics Modeling is an intensive 3-day instruction covering the fundamentals of FRED’s physical optics propagator, modeling diffraction phenomena, modeling interference phenomena, defining coherent sources, diagnosing and debugging propagation problems, and configuring models for polarization applications.  Emphasis is placed on the practical use of FRED as an engineering tool for physical optics modeling.


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Topics Covered in this Tutorial

  • Introduction
    • A brief overview of propagation algorithms in raytracing applications
    • Introduction to Gaussian Beam Decomposition
    • Review of Gaussian beam properties
    • The details of complex raytracing
  • Diffraction Modeling
    • Fraunhoffer diffraction effects
    • Fresnel diffraction effects
    • Transverse and longitudinal field calculations
    • Wavefront analysis
    • Near-field diffraction effects
  • Interference Modeling
    • Two beam interference
    • Configuring surface properties for interference effects
    • Multiple beam interference applications
    • Interference of polychromatic sources
  • Configuring Coherent Sources
    • How coherent sources are constructed
    • Verifying source configurations
    • Different ways of specifying Gaussian beams
    • Beam quality and M-squared sources
    • Customizing coherent source definitions
  • Beamlet errors, limitations and resampling
    • The rules of complex raytracing
    • Review of beamlet failure mechanisms
    • Advanced coherent source controls
    • Spatial field resampling
    • Directional field resampling
  • Polarization
    • Review of basic polarization definitions
    • Specifying starting source polarization
    • Tools for polarization analysis
    • Analyzing effects from coatings and materials
    • Polarization specification of diverging sources
    • Stokes analysis



Attendees should have a rudimentary knowledge of geometrical and physical optics and must be familiar with the basic operation of FRED.  Experience with FRED’s BASIC scripting language is also helpful.