May 13, 2019

prysm is an open-source library for physical and first-order modeling of optical systems and analysis of related data. It is an unaffiliated sister library to PROPER and POPPY, codes developed to do physical optics modeling for primarily space-based systems. Prysm has a more restrictive capability in that domain, notably lacking multi-plane diffraction propagation, but also offers a broader set of features.

Use Cases

prysm aims to be a swiss army knife for optical engineers and students. Its primary use cases include:

  • Analysis of optical data

  • robust numerical modeling of optical and opto-electronic systems based on physical optics

  • wavefront sensing

Please see the Features section for more details.

prysm is on pypi:

>>> pip install prysm

prysm requires only numpy and scipy.

If your environment has numba installed, it will automatically accelerate many of prysm’s compuations. To use an nVidia GPU, you must have cupy installed. Plotting uses matplotlib. Images are read and written with imageio. Some MTF utilities utilize pandas. Reading of Zygo datx files requires h5py.

pip can be directed to install these,

>>> pip install prysm[cpu]     # for numba
>>> pip install prysm[cuda]    # for cupy
>>> pip install prysm[img]     # for imageio
>>> pip install prysm[Mx]      # for h5py
>>> pip install prysm[mtf]     # for pandas
>>> pip install prysm[deluxe]  # I want it all

or they may be installed at any time.


Physical Optics

  • Modeing of pupil planes via or with:

    • Fringe Zernike polynomials up to Z48, unit amplitude or RMS

    • Noll (“Zemax Standard”) Zernike polynomials up to Z36, unit amplitude or RMS

    • apodization

    • masks

      • circles and ellipses

      • n sided regular polygons

      • user-provided

    • synthetic fringe maps

    • PV, RMS, stdev, Sa, Strehl evaluation

    • plotting

  • Propagation of pupil planes via Fresnel transforms to Point Spread Functions (PSFs), which support

    • calculation and plotting of encircled energy

    • evaluation and plotting of slices

    • 2D plotting with or without power law or logarithmic scaling

  • Computation of MTF from PSFs via the FFT method

    • MTF Full-Field Displays

    • MTF vs Field vs Focus

      • Best Individual Focus

      • Best Average Focus

    • evaluation at

      • exact Cartesian spatial frequencies

      • exact polar spatial frequencies

      • Azimuthal average

    • 2D and slice plotting

  • Rich tools for convolution of PSFs with images or synthetic objects:

    • pinholes

    • slits

    • Siemens stars

    • tilted squares

    • slanted edges

    • gratings

    • arrays of gratings

    • chirps

  • read, write, and display of images

  • Detector models for e.g. STOP analysis or image synthesis

  • image-chain degredation models:

    • smear

    • jitter

    • atmospheric seeing

  • Interferometric analysis

    • cropping

    • masking

    • spatial filtering

    • least-squares fitting and subtraction of Zernike modes, planes, and spheres

    • evaluation of PV, RMS, stdev, Sa, band-limited RMS, total integrated scatter

    • computation of PSD

      • 2D

      • x, y, azimuthally averaged slices

      • evaluation and/or comparison to ab (power law) or abc (Lorentzian) models

    • spike clipping

    • plotting

First-Order Optics

  • object-image distance relations

  • F/#, NA

  • lateral and longitudinal magnification

  • defocus-deltaZ relation

  • two lens EFL and BFL

Parsing Data from Commercial & Open Source Instruments

  • Trioptics ImageMaster MTF benches

  • Zygo interferometers

  • SigFit

  • MTF Mapper