In a broad, definitional sense, a “source” is a collection of rays
with specific properties, (i.e., coherence, wavelength, power,
phase, etc) selected by the user to simulate the emission
characteristics of an entity (i.e., star, blackbody or thermal
source) or device (i.e., LED, laser, arc lamp).
FRED
can accurately simulate virtually any light source.
The user can create and trace as many sources as necessary,
each with its own unique set of properties.
Source properties include:
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• |
Ray position
(specified by rectilinear/hexapolar grids, random
planar/volume, random points on a surface, bitmap,
user-defined) |
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• |
Ray direction
(specified by single/multiple direction vector(s),
converging/diverging, angular range, 4π
steradians,
astigmatic foci) |
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• |
Location/orientation |
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Total power |
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• |
Position
apodization function (uniform, Gaussian, r ,
user-defined) |
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Direction
apodization function (Lambertian, inverse Lambertian,
rn, cosn, sinn
sampled in spherical coordinates, user-defined) |
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• |
Coherence state
(incoherent or coherent) |
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• |
Polarization
state (unpolarized or polarized with specific
ellipticity, handedness, and orientation) |
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• |
Wavelengths
(unlimited set of wavelengths, associated weights, and
ray colors. Arbitrary colors may be specified by
chromaticity coordinate, tristimulus value, or RGB
value; these colors may be simulated with a user-defined
basis set of wavelengths.) |
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• |
Immersion
material |
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• |
Post-construction
propagation |
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• |
Post-construction
constant phase shift |
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• |
Visualization
(prior to raytracing/during raytracing) |
|
FRED model of HP LED
Bitmap source imaged through symmetric lens
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