Hi Taynara, 





If you'd like to model propagation within the fiber, your best best is to use Non-Sequential Mode. This is because it will allow you to model both the core and the cladding, if needed. With this, if you're trying to model a parabolic profile, you can use the "grin1.dll" profile. I'd recommend taking a look at the sample file, "...\Zemax\Samples\Non-sequential\Fibers\grating-grin-fiber.ZMX" for an example of how to do this. 





You can also model this type of profile in Sequential Mode using the Gradient 1, 2, 3, etc. surfaces, as you've identified. If you're just hoping to model coupling into a fiber, I'd recommend going this route and checking out the article, Single-mode fiber coupling in OpticStudio, for an example. 





Regarding your question on other methods for simulating the GRIN profile, what sort of information do you have regarding the profile? Do you have an equation, sampled data set, etc.? Depending on the type of information you have, the approach might vary. 





Have a great weekend!





Cheers,


Nick 

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Hi Nick,





Thank you so much for your reply. I will take a look in that sample file. 





About the article Single-mode fiber coupling in OpticStudio I used to model a designing using microlens. It is very useful, thanks. 





But I was wondering it is possible to model in Zemax a thin film stack based GRIN lens. As a matter of fact I have a simple algorithm and the refractive index profile of the GRIN lens can be generated layer by layer. You can check the attached picture. Can I insert this formula in some database in Zemax to model every layer of my stack based GRIN lens and simulate the ray tracing passing through the lens as Numerical software do it?





To visualize what I mean in attached I have a picture of the grin lens that I want to evaluate using Zemax.





Nick, I appreciate any help. Thanks. 





Have a great week !





Best regards,


Taynara Oliveira














 

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Hi Taynara, 





I hope you had a nice weekend! And no worries, I'm happy to help. :)





To answer your question here, it depends on what you're hoping to model. As a general rule in OpticStudio, as long as the optical components in the system are larger than about 10x the System Wavelengths and accurate dispersion data is available, OpticStudio can be used to model propagation through those components (check out this thread for some more info). Given that you have a 12um stack here, this condition likely won't hold, so standard ray tracing alone will likely not model the propagation accurately.  





That said, you can still model such a thin film stack using a coating. To this end, you can use the COAT coating type and define each layer as a separate material with a different index in your COATING.DAT file. Then apply this to the appropriate surface in your system. We have a tutorial on how to model this sort of stack here: How to define metal materials in OpticStudio. 





Check this out and let us know if you have any questions. Thanks, and have a great week!





Cheers,


Nick





P.S. If you do change the COATING.DAT file, make sure to save it to a new name. If you don't the next time you install a new version of OpticStudio, your changes will be overwritten. 

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Please I am stuck in my research. I am need to inmclude some basic simulations of grin lenses using Zemax but i have no clue. I have read a lot and watched couple of videos. I guess I still need someone more familiar to put me through some technicalities. Anyone available to help? I can share my email or my phone number. Thanks in anticipation

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Hi Omena, 

Thanks for the question here. We do limit live support calls for students using our software, but we'd be happy to help you out here on the fourm. Can you go ahead and create a new forum thread outlining some of the questions you have? We can then have a conversation there specifically for your use case. 

Thanks, and I look forward to hearing more about your questions. 

Cheers,


Nick

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