What is DIFFRACT?

DIFFRACT is a software package that helps you simulate coherent beams of light as they propagate through an optical system. DIFFRACT enables you to:

• Accurately analyze and study diverse optical systems.
• Accurately tolerance your optical design by stepping through a set of adjustments for any part of the system (from source to detectors – including: lasers, lenses, mirrors, polarization optics, diffraction gratings, prisms, apertures, phase/amplitude masks, multilayer stacks, detectors, etc.) and allowing you to inspect the resulting optical patterns at various cross-sections of the beam
• Keep track of polarization, inspecting the amplitude, phase and polarization state of the beam at various stages throughout the system.
• Study fascinating phenomena of classical optics such as: the Talbot effect, optics of biaxially birefringent crystals, surface plasmon excitation, magneto-optical Faraday and Kerr effects, the principle of holography, evanescent coupling through frustrated/attenuated total internal reflection, self-focusing and filamentation in non-linear media, electromagnetic confinement in resonant cavities, internal and external conical refraction, the Goos-Hänchen effect and many more.

Many optical systems can be modeled and analyzed in DIFFRACT. From the simplest system consisting of a single optical element, to complex systems with tens of optical surfaces, lenses, mirrors, gratings, polarization optics, etc.

Here is a list of the menu options presently available in DIFFRACT:

• Incident Beam (BEAM)
• Retrieve Distribution (READ)
• Propagate in Free Space (PROP)
• Positive Focusing Lens (PFOC)
• Collimator (COLL)
• Cylindrical Lens (CYLN)
• Astigmatic Lens (ASLN)
• Toric Ring Lens (TRLN)
• Split Lens (SPLN)
• Clear Aperture (CLAP)
• Phase /Amplitude Mask (MASK)
• Polarization Element (POLE)
• Flat Mirror (MIRR)
• Multilayer Structure (MLYR)
• Optical Disk Surface (DISK)

• Diffraction Grating (GRAT)
• Rescale the Mesh (RSCL)
• Change Coordinate System (CSYS)
• Weak Biprism (BIPR)
• Convert to Rays (RAYS)
• Trace Rays (TRAY)
• Extract Phase/Amplitude (XTRC)
• Detector (DTCT)
• Phase/Amplitude Object (XOBJ)
• Interfere (INTF)
• Measure Peak and FWHM (MEAS)
• Process Signals (PSIG)
• File Management/Graphics (FMAN)
• Plot Data (PLOT)
• Store Distribution (STOR)

Many of the menu options provide a multitude of choices to select from. For instance:

• the Polarization Element could be a quarter-wave plate, a half-wave plate, a Soleil-Babinet compensator, a polarizer or a leaky polarizing beam-splitter.
• The Multilayer option allows the user to simulate a structure having an arbitrary number of layers: metals, dielectrics, birefringent crystals, anisotropic plastics, and magneto-optically active layers are allowed. Thus, one can tailor the Multilayer to represent a Faraday rotator, a uniaxial or a biaxial crystal slab, a dielectric mirror, an anti-reflection coated surface, a Fabry-Perot resonator and other devices.
• Ray Trace option allows the modeling of an arbitrary system consisting of lenses, mirrors and apertures, with the provision that each optical surface be flat, spherical, conical or aspherical.

The user may select any number of optical elements from the menu of DIFFRACT, place them in various spatial relations to each other, and investigate the properties of a coherent beam of light as it propagates through such a system.