how to simulate a diffuser (0.1 degree) in sequential lens design?

  • 18 February 2021
  • 7 replies
  • 1311 views

I would like to get help to simulate insertion of a diffuser (0.1 degree) in the optical path in order to improve output uniformity.


7 replies

Userlevel 5
Badge +1

Hi Ying!


Thanks for your post here. To simulate a small angle scattering effect, you are able to define a scattering profile on any surface in a Sequential Mode file using the Surface Properties:

 


 

 


You've already addressed the scope of your scattering effect with your 0.1 degree range output, but just to re-iterate, scattering in Sequential Mode has the most utility in small-angle scattering. The following is from our Help Files at 'The Setup Tab > Editors Group (Setup Tab) > Lens Data Editor > Surface Properties > Scattering (surface properties)':






 


In addition, you will need to ensure that you have checked on 'Scatter Rays' in the analyses that support the ability to take into account scattering rays. These analyses will be limited to those strictly accounting for the geometric trace treatment of light, i.e. Spot Diagram, Geometric MTF, etc.:

 




 




 


You can take a look at the article here for some more discussion on the different scattering profiles that are definable in OpticStudio.


Lastly, I just wanted to note that while you can perform some scattering analysis with Sequential Mode, scattering is handled much more robustly in Non-Sequential Mode, especially if you're looking to do more in-depth analysis (such as seeing the effects of scattered light that might hit different surfaces in an order other than that prescribed in the LDE).


Let us know how these thoughts work out for you!


~ Angel

Userlevel 5
Badge +1

Hi again,


Just wanted to make a quick follow-up post to share the example file I used for the screenshots, in case you wanted to take a closer look at it!


~ Angel

 


 

Userlevel 6
Badge +2

Hi Ying!


Your last message is empty. Do you have any questions?


Thank you!


Sandrine

Hi, do you know how to simulate diffuser as shown in the graph below that I copied from a paper? Thanks


 


Userlevel 6
Badge +2

Hello Ying!


Well it is only a sketch so hard to tell. But if the scattering has a narrow angular distribution, you could have a look at the gaussian scattering. We have an article that describes the scattering models of OpticStudio: What scattering models are available in OpticStudio?


Then you can check the distribution in the software under Libraries...Scatter Function Viewer and Scatter Polar Plot.


Sandrine

Hello all,


I am very thankful to all of you to discuss the problem here which is very helpful for the people using Zemax. I have some doubt and it will be great for me to hear from you and will be very thankful to you. Can I use the user-defined DLL file in sequential mode to model the diffuser (20Degrees)? If yes, how can I use this property of the Zemax to model this?. It's working in the Non-sequential mode but not in sequential mode. I need to find the beam divergence after the lens followed by the diffuser. Is it possible to find out the beam divergence in the non-sequential model? It will be very great to hear from you people.


Best and Regards,

Faheem Ahmad

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