Hi Xin Soh,

Assuming your distribution is not affected by pixel noise (that is, you have traced enough rays), you can use NSDD operand in the merit function to return the standard deviation.

Look for “NSC Operands” page in the help. It contains a table of what values to use for the Pix# and Data#. In you case, Pix# should be -4, and Data# can be 0 or 1.

You can also access this data in ZPL scripts using NSDD function, and in extensions with NSCDetectorData command (use of extensions are deprecated).

Thanks Ray! 

@Kai Xin.Soh - to add on to what Ray said, you can see an example of uniformity analysis in the Knowledgebase article “Using the OpticStudio Non-Sequential Optimization Wizards”. The section Projector example builds a Merit Function around spatial uniformity on the detector. 

Hi Ray and Allie, Thanks for your help!

Sorry to bother you again @Ray, after I set up the merit function, I can’t run it since I don’t have a variable. So what must I do to get the Standard Deviation value? Am I suppose to run a Universal Plot?Sorry if it seems obvious, I am not very familiar with the software.