I'd like to use the ZPL function DEFAULTMERIT to make a default merit function with the below settings:If I use data = 8 is makes a contrast merit function, but seems to be unsupported in the documentation.I can't see how to set the spatial frequencyor how to limit the merit function to config 1Thanks for any advice,John

How do I turn this off? We pay to use Zemax, not to be an advertiser for Ansys.

Hi all: How can I compute the Return Loss coupled into source fiber due to back reflection in a system?For example: I would like to know how much light is reflected back from the Image surface with AR coating back into my source fiber as indicated by the BLUE arrow. One way would be to make the Image Surface material == MIRROR, but how can I determine how much light is coupled back into Source fiber originating from the Image Surface AR coating?Example design file can be downloaded from here.Cheers!

Dear all, I am trying to replicate the optical design of a Schwarzschild imaging spectrometer of the paper Xue, Qingsheng. "Modified Schwarzschild imaging spectrometer with a low F-number and a long slit." Applied Optics 52.28 (2013): 6956-6961, also included in attachment.More specifically, I am interested in the design using only concentric spherical mirrors. I used the values from their Table 1 and first column of Table 2 (they seem consistent with their formulas), giving the Zemax design also included in attachment.However, I do not get even close to the performance they show in Figure 7b, where my spot sizes are about 10x larger, even with a higher f/#. And even allowing a small deviation to the initial values and re-optimizing did not significantly improve the results.Does anyone have experience with this particular design or see any obvious mistakes? Thanks for your help,Best regards,Indy Magnus

Hello I have some trouble in defining the ISO file of an off axis conic mirror. The design looks like that and the I can manage to do better for the ISO file.   How do you proceed in such a case ? Thank you very much in advance for your help and have a nice day Pascale  

​@MichaelH ​I have a discrepancy when converting from a rotation matrix to tilt XYZ values when I use your ZPL19 macro compared to a macro I wrote. The values in my macro agree with tilt values calculated using ATAN2 in excel.I can’t share the file, but here is the merit function showing the rotation matrix for a given surface. Also shown are the 3 outputs of the ZPL19 macro. The tilt Z value of 180° does not agree with a macro I wrote or ATAN2 in excel. I even used some if statements to match your ZPL19 macro steps in excel, but even this disagrees with the macro in Zemax. See below.Any thoughts? Also, this is one more request for a built-in ZPL function or merit function operand to report tilt X, Y, Z values for a given surface.-Sean