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The General Optical Systems Evaluation Program, GENOPTICS, was developed as an aid for the analysis and evaluation of optical systems that employ lenses, mirrors, diffraction gratings, and other geometrical surfaces. The GENOPTICS evaluation is performed by means of geometrical ray tracing based upon Snell's law. The GENOPTICS program can provide for the exact ray tracing of as many as 800 rays through as many as 40 surfaces. These surfaces may be planar, conic, toric, or polynomial shaped lenses, mirrors, and diffraction gratings. Each surface may be tilted about as many as three axes and may be decentered. Surfaces having bilateral symmetry may also be analyzed. GENOPTICS provides for user-oriented input and for a wide range of output for the evaluation of the optical system being analyzed.

GENOPTICS provides a wide range of features for the optical system analyst. GENOPTICS performs paraxial ray tracing and computation of the third order aberrations including aspheric contribution. Graphical output can be generated for spot diagrams, radial energy distributions, and modulation transfer functions, for each object point and each color. Sag tables may be generated for any rotationally symmetric surface, with options to obtain the sag differences from a reference sphere in units of lengths or wavelengths. Statistics and plots of ray intercepts with any surface in the system may be obtained for use in vignetting analysis and beam distribution analysis. Afocal systems can be examined with image statistics generated in terms of tangents of angles with respect to the optical axis. For exact ray tracing, a ray pattern at the entrance pupil can be specified as a rectangular or polar grid, where each ray samples an equal amount of area, or as a pattern where each ray samples an equal amount of solid angle for a finite object. This latter pattern is useful in radiometric work.

Input to GENOPTICS includes program control statements, system definition data, surface data, and task data. The user can specify which portions of an analysis are to be printed. Optional printout includes system data, surface-to-surface printout of each ray, modulation transfer function values, radial energy distribution values, and paraxial ray data including aberrations. ( NASA Goddard Space Flight Center )

This program was released by NASA through COSMIC as GSC-12823. The italicized text above is from the official NASA release.

PDAS home > Contents > Optics
Public Domain Aeronautical Software (PDAS)