Birefringent Material Temperature Modification

Currently, FRED does not support “global” temperature settings and evaluations of temperature sensitivity are generally undertaken using the scripting language.  This knowledge base article demonstrates a script which implements a change in refractive index with temperature for a birefringent material.

The attached example file contains two birefringent material models, “KDP” and “KDP Baseline”.  The KDP Baseline material stores the refractive index values at a known temperature.  The KDP material is used to store the refractive index values at the “current” temperature, specified as a temperature difference from the baseline material.  An embedded script called “modifyBirefringentMaterialIndex” is included with the FRED file and also attached separately as a script file.  It’s implementation is the following

  1. Retrieve the node numbers for the two materials, KDP and KDP Baseline
  2. User specifies CTE for the ordinary and extraordinary refractive index values as well as the temperature difference from the baseline
  3. Loop over the baseline material samples and determine the number of wavelength entries
  4. Loop over each sampled wavelength entry in the baseline material
    1. Modify the ordinary and extraordinary refractive index values using (2) above
    2. Apply the modified values to the non-baseline material
  5. Set a description on the non-baseline material indicating the temperature change from baseline

Download the FRED script modifyBirefringentMaterialIndex.frs

Download the FRED file birefringentMaterialTemperatureModification.frd