CODE V Enewsletter

May 2020

Want to Expand Your CODE V Optimization Toolbox?

When to Use the Fill Aperture Ray Grid Control

As part of a typical lens optimization process, a grid of rays is traced each optimization cycle to evaluate the error function and variable derivative increments. Smooth optimization convergence relies on a consistent set of rays impacting the error function. The default settings for CODE V’s Automatic Design aims rays at the vignetted entrance pupil, which has flexibility and speed benefits for optimization, and works effectively for most imaging systems. 

Some systems specify no vignetting. In these systems, the light bundle is controlled by the stop and will not be clipped at other surfaces. In these systems, CODE V vignetting factors should be set so the vignetted pupil corresponds with filling the stop initially. (Note that you can quickly set the CODE V vignetting factors to match the lens apertures by selecting the menu Lens > System Data > Fields/Vignetting and clicking the Set Vignetting button, or by running the SETVIG supplied macro: “IN CV_MACRO:SETVIG”.)

However, as the optimizer changes the system, the vignetted pupil may drift from filling the stop. In many scenarios the impact on converging to a solution is minimal, but there may be efficiency to be gained when optimizing systems where the stop is near the back of the optical train and closer to the image (see figure below). 

In such a case, you must take care about the system vignetting factors and also ensure the ray grids fill the stop. While you can re-set the CODE V vignetting factors periodically, an efficient alternative is to use the Fill Aperture command (FAP Y). The FAP command will switch the optimizer to use a ray grid that fills a specified surface aperture. Typically, you’d select the stop or some other intermediate pupil. You can enable FAP from the Error Function Setup tab > Ray Grid for optimization button > Fill aperture on surface.

If you do enable FAP, the pupil size may change during optimization. So be sure to check, and if needed, constrain, the system f/number. 

For more on this tip, and other CODE V tips you might not be aware of, tune into the “CODE V Features that you may not know about…” webinar on May 20. If you miss it, view the recording for this webinar (and others) on the Customer Support Portal OSG Online Tech Talks page.

CODE V User Group Meetings

Due to the worldwide COVID-19 situation, we will not be hosting our traditional in-person CODE V User Group Meetings this summer. Instead, we hope that you can join us for the OSG Online Tech Talks series, featuring a wide variety of topics, from case studies, to feature training, and more. You can find more information about the OSG Online Tech Talks series on our website. 


New Blog Entries

Synopsys Optical and Photonics Solutions – Robert S. Hilbert Memorial Optical Design Competition

The Synopsys Optical Solutions Group invites you to participate in its Robert S. Hilbert Memorial Optical Design Competition, which recognizes excellence in optical design projects completed by students.  You’ll have a chance to win a portion of a $10,000 prize.  Entries are due on June 15, 2020.

We Just Added More Tech Talks!

The Synopsys Optical Solutions Group is proud to announce our new series of online tech talks. We’ve pulled together a great lineup featuring product training and optical design case studies. Register today for any or all of these talks! 

Calendar of Events

For the latest event calendar, please go to our Events page.



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