​@yfei 

It seems to work for me. Since I’m not sure what you tried exactly, I cannot say what went wrong. Perhaps I am misunderstanding the question.

This is what I think you are after (rays are colored by wavelength):

I used the case of EGFP with an excitation of 0.488um that goes through the dichroic and causes fluorescence at 0.510um in the vertical Rectangular Volume on the right-hand side of the NSC 3D Layout. The fluorescence is then reflected at the dichroic thanks to its coating and is terminated on a horizontal rectangle at the top of the figure.

If that’s what you want, then here are the steps I followed:

• Set excitation and emission wavelengths in the System Explorer (as described in https://support.zemax.com/hc/en-us/articles/1500005575642-How-to-model-fluorescence-using-bulk-scattering)

• Change the Volume Physics of the sample to show fluorescence (note I used 180 degree angle so that the rays can also come back towards the dichroic)

  

• Change the Source to Bulk Scatter once (as described in https://support.zemax.com/hc/en-us/articles/1500005575642-How-to-model-fluorescence-using-bulk-scattering)

• Define a “GFP” coating (transmit shorter than 0.499um, and reflect longer than 0.500um)

TABLE GFP
ANGL 0.0
WAVE 0.499 0.0 0.0 1.0 1.0 0.0 0.0 0.0 0.0
WAVE 0.500 1.0 1.0 0.0 0.0 0.0 0.0 0.0 0.0

• Apply the coating to the back face of the dichroic

• Apply a Filter String in the NSC 3D Layout to only show rays that have reflected on the dichroic (R2 in my case)

I am also attaching my file here for your reference.

Take care,

David

Hello, David. Thanks for the answer. 

Latest Update: I was able to correctly have the rays reflected off the dichroic mirror. The solution was to check Split NSC Rays. Could you please explain why this was the critical thing? 

Thank you so much. 

---------------------------------------------------------------

I understand how you did this and I tried to replicate the same sturcture with some modifications: 

1. Used 910nm instead of 488nm 
2. Used mie scatter instead of bulk scattering
3. Added a few piece of lens after the dichroic mirror to simulate an objective

The coating table I wrote is:  full reflectance for 510nm, and tranmission for 910 nm. 
TABLE GFP910
ANGL 45
WAVE 0.510 1.0 1.0 0.0 0.0 0.0 0.0 0.0 0.0
WAVE 0.910 0.0 0.0 1.0 1.0 0.0 0.0 0.0 0.0
 

Somehow this will not allow me to have a reflective ray from the dichroic. The layout will look at the following graph. Do you happen to know what the problem would be? 

Thank a lot. 

​@yfei 

Hard to know like this, could you upload an archive?

Take care,

David