Solved

Average transmission for a wavelength using POLDEFINE/POLTRACE

  • 3 October 2022
  • 3 replies
  • 79 views

Userlevel 1
Badge

From the OpticStudio manual under Defining Initial Polarization: “No matter which method is selected, the transmission results for unpolarized light will be unaffected because any two orthogonal rays may be traced to compute transmission.”

Does this mean that I can use POLDEFINE 1, 0, 0, 0 followed by a POLTRACE and then POLDEFINE 0, 1, 0, 0 followed by another POLTRACE and average those results to get an average transmission at a given wavelength?

icon

Best answer by Mark.Nicholson 3 October 2022, 18:54

View original

3 replies

Userlevel 7
Badge +3

Yes. Unpolarized light transmission can be modeled by tracing any two, orthogonally polarized rays and averaging the result.

Userlevel 1
Badge

Thanks, Mark.  Just needed some reassurance on that.  I appreciate your rapid response, sir.  -Alex

Userlevel 6
Badge +2

Hi John, 

Yes, OpticStudio always needs to trace 2 rays when performing a polarization ray trace for unpolarized rays (you need a polarization ray trace to account for things like Fresnel reflections and bulk absorption, even if you want to analyze unpolarized light).

I like to use the CODA Merit Function Operand to investigate polarization ray trace and to compare to ZPL results for verification: 

 

And the ZPL code is:

FORMAT 0.6
POLDEFINE 1, 0, 0, 0
POLTRACE 0, 0, 0, 1, PWAV(), 1, NSUR()

POLDEFINE 0, 1, 0, 0
POLTRACE 0, 0, 0, 1, PWAV(), 2, NSUR()

PRINT "Jx intensity : ", VEC1(1)
PRINT "Jy intensity : ", VEC2(1)
PRINT "Average : ", (VEC1(1) + VEC2(1)) / 2

 

Reply