Hi Domingo,

If you want to input a CAD surface into Sequential Mode, you can do so with a Mixed Mode system. This type of setup is described in the Knowledgebase articles below:

• 
  
  

  How to model a mixed sequential/non-sequential system

  
  
  



• 
  
  

  Creating sequential systems with prisms, CAD parts and other complex objects - webinar

  
  
  

If you are looking for a way to model a custom surface shape in Sequential Mode, this is also possible with a DLL or Grid Sag surface. If you have an equation for the surface shape, those surface types may be more useful than an imported CAD object. 

Let me know if you have any questions about this!

Best,

Allie

Hello Allie,

Thanks a lot for your comment. It was a great help. I have retaked this study again and now I am lost trying to built a truefreeform surface to perform the output of the lens (the entry surface is a given surface) , but I can not do it well, every try to optimize the merit function, the trufreeform is nonsense, even using GOPT to control de grip. Where can I find more information about how to use truefreeform surfaces? I have seen 'Using the TrueFreeForm surface​ for grid based freeform optimization' but there is no complete explanation about how to use it or to avoid this nonsense surfaces. Thanks a lot.

Just to clarify, when I said nonsense surfaces I meant surfaces corrupted, which are not allowed to be exported.