Optical Ray Tracing Software

Specifications

Optical Elements

Optical elements may be rotated and offset in any direction. Optics may be placed anywhere in 3 dimensions. 120 optical elements may be used at once. An optic such as a lens, prism, or cube beamsplitter counts as only one element even though it may have many surfaces.

Lenses: PCV, PCC, DCV, DCC: you specify focal length, thickness, diameter, and glass.

Any Simple Lens: you specify 2 radii, thickness, diameter, and glass.

Solid Doublet, Triplet: you specify 3 or 4 radii, each thickness, diameter, and 2 or 3 glasses.

Prisms: right angle, porro, equilateral, wedge, ideal rotator. You can make your own also.

Mirrors: flat, spherical, paraboloid, prolate and oblate ellipsoid, hyperboloid. May have a center hole.

Beam splitters: flat, cube, dichroic, pellicle.

Diffraction gratings: Reflection or Transmission. Flat or curved surface. Orders: +2, +1, 0, -1 (two at once).

Apertures: Circular, square, slit, struts, cone, cylinder, square tube with holes. Walls may reflect or absorb.

Aspheric elements: reflective, refractive, or beam splitter, many surface options (some listed below).

Any conic section. Specified using Schwarzchild constant and radius.

16th order polynomial (radial, X, or Y).

Can be used for Cylinder lenses, Toroids, Mangin mirrors, light pipes, Fresnel lens, and others.

Schmidt corrector plate coefficients may be generated automatically (6th order).

Optic may be square or circular with a square or circular hole.

Can generate ghost reflections from both surfaces at once. Reflection and Transmission Coefficients.

Surfaces may be Lambertian scatterers.

Detectors: Quad Cell, CCD (any size to 32k by 32k), and single detectors. Specify Spectral Response.

Mechanical elements: Shutter, Chopper, ND Filter Wheel. Tilt and position control with all optics.

Outputs

The results of the ray trace may be measured at up to 4 user selected planes at once. Each plot is displayed in its own window and may be printed. Data may be displayed as a:

Spot Diagram: best focus option, multiple colors at once, spot size and Airy disk are displayed.

Wavefront: remove curvature option, peak to peak value displayed.

Point Spread Function: Strehl ratio shown, focus offset option.

MTF: Plot Phase, Magnitude, or both. Diffraction limit shown. Geometric or Pupil Autocorrelation.

Secondary Spectrum: shows focus shift as a function of wavelength for up to 6 colors.

Encircled Energy: shows the energy inside a circle as a function of radius of the circle.

Curvature of Field: plotted for best focus, tangential focus, or saggital focus.

Distortion: options for angular or rectilinear distortion plot.

Simulation: 4 channel "oscilloscope" display with typical scope display controls.

Other information such as ray trace data may be saved to a text file.

Source

The light source represents a point source or plane wave and may be placed anywhere with any orientation or curvature. One to six colors may be traced at once. A 2-D pattern of up to 1871 rays or a 1-D pattern of up to 33 rays in one color may be selected. If more than one color is used the limit is 225 rays in each color. The wavelength for each color may be changed. An extended light source (a 7 by 7 array of points) is an option. The intensity of each point may be set. There may be up to six light sources with a total of six different colors.

Precision

All ray tracing calculations are done using double precision floating point arithmetic. All dimensions are in metric units.

Optimization

An easy-to-use optimizer with two algorithms is included. One algorithm is a variation of the dampened least squares approach and the other is the simulated annealing algorithm. The merit function may include spot size, wavefront error, Strehl ratio, MTF, curvature, distortion, secondary spectrum, and glass thickness. Any number of parameters may be varied at once. Parameters may be "linked" to the values of other parameters. Limits on the values of the parameters may be set manually or automatically. System magnification, focal length, and F# are automatically maintained. Optimize with up to 6 wavelengths over any field of view. Only real glasses are used. All options are entered with easy-to-use dialog boxes.

Simulation

Simulation involves three major functions: a detector, signal processing, and the controlled function. A detector (quad cell, CCD, or single detector) is placed in the optical layout like any other component. The output of a single detector is the incident power. The outputs from a quad cell are the power and the 2 axis spot position based on the usual quad cell algorithm: (a-b)/(a+b) where a and b are the power incident on each half of the detector. The outputs from a CCD are the power and the 2 axis spot position calculated from the centroid of the spot pattern after quantization by the detector pattern. In addition all detectors output the actual spot position calculated from the centroid of the spot pattern.

The detector outputs are processed to develop the control signals. A dialog box is used to select the detector output and specify the processing. The signal may be integrated, differentiated, scaled, filtered with a digital or analog filter, processed by a math function such as sin or cos, or combined with another control signal or variable. You model your control electronics with these options.

The optical parameter to be controlled (such as position or tilt) is set equal to the output of the signal processing block. Any dynamics associated with the mechanical system (such as lag) must be modeled as part of the signal processing block. Up to 60 parameters may be controlled at once.

A simulation is run by selecting the number of frames and clicking the start button. After each ray trace the detector outputs are calculated, the signal processor outputs are updated, and the optical parameter is changed. The process repeats for the specified number of frames. Any parameter may be displayed as it changes.

Glasses

Refractive elements are assigned 6 different indices of refraction: one for each of the 6 wavelengths that may be used at once. 300 sets of indices are included for real and ideal materials. Another 700 sets may be added.

Printing

Hard copy is produced with your normal Windows printer. All or part of the optical layout may be printed. Labels and dimensions may be added. The output plots may be printed either 1 or 4 to a page. A report with all the optical system parameters may be printed or saved to a file. Supports both Monochrome and Color printing.

Polarization

Reflection and transmission coefficients for each polarization may be specified. These do not vary with angle of incidence. No other polarization effects are included.

Computer System Requirements

An IBM compatible computer, 1024 by 768 or higher resolution graphics, true color graphics (24 or 32 bit), and a mouse are required. Compatible with Windows 7, Vista, XP, and 2000. Requires about 3 MBytes hard disk space. Please verify compatibility with your graphics hardware and software by trying the demo version.

Specifications are subject to change without notice.