The most general description of a complex source is given in a Radiant Source Model (RSMX) file. This file contains the measured radiant or luminous intensity of the source as a function of wavelength, position, and angle. As such, this file can be accurately used to characterize the behavior of the source in both the near- and far-fields.
Let us take this source (183053) as an example
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Download the RSMX file using the “Download Radiant Source Model Data” feature.
Generating a Spectral Color Format file
The source model that was chosen in the previous step did not include measurements of the source spectrum, so within the ray generation tool we have an option to specify the spectral distribution for the rays. For this case, the spectrum type is blackbody, 2900.
Validating the results
To confirm accuracy of the ray generation, we may view the far-field distributions for both the RSMX and SDF files
Validate the color
The agreement is excellent, as expected.
Check it by the source illumination map
Again, excellent agreement is observed !