Spectral flux and angular emission patterns combination source

  • 26 March 2021
  • 5 replies

I have spectral flux and angular emission patterns for a unique led source that does not exisit in any libraries. What is the best way to model this source in zemax? My current plan is to use the radial source type and then enter the wavelengths with weighting manually on the system explorer with weightings relative to the spectral flux. Will this achieve what I think it will and combine the data to make an appropriate model of the source? Is there a way to import a file for the wavelengths to avoid manual entry?  

5 replies

Userlevel 7
Badge +3

Does your data include spatial information? If not, the IESNA data format is probably just what you need.

The descriptions of IES files I've read seem to only use angle, not wavelength. I was hoping for a way that includes both?

Userlevel 7
Badge +3

Oops, sorry I should have been clearer. Create one IES file per wavelength, and use multiple IESNA sources, all co-located.

does the IES file have a relationship with wavelength I thought it was just intensity based. So there is no way to enter in wavelength data such as spectral flux vs wavelength?

Userlevel 5
Badge +1

Hi Lucy,

The IES files only have information on ray angle data. To consider the spectrum of the source, one way would be to use different IESNA files for different wavelengths. Another approach is that you can effectively 'overlay' spectral data onto source objects with a Spectrum File (extension .SPCD). The following is in our Help Files at 'The Setup Tab > Editors Group (Setup Tab) > Non-sequential Component Editor > Object Properties (non-sequential component editor) > Sources > Defining a spectrum file':


You can then use this .SPCD file with the IESNA file if you go into the Object Properties...Sources tab and go to the Color/Spectrum section:

Whichever you'd like to take I think depends on the source. For example, the following Knowledgebase article demostrates the need for two separate Source File objects in order to better capture the angular intensities of the 'blue' and 'yellow' portions of the spectrum of a white LED:

Let us know how these thoughts work out for you!

~ Angel