Learning Forum

[yenmst99]

Hi everyone!
I'm a beginner at Zemax. I'm simulating the eye, using Marginal ray height to solve the thickness of surface 4. However, whenever I click on FIRST order in the Macro list to find the focal length, the value at the LDE turns out to be 0.

[npapachr]

Hi Subscriber,

Thank you for reaching out to us! I believe that the reason you see this discrepance is because of the fact that "Since the marginal ray has a height of zero (it crosses the axis) at the paraxial image surface (assuming a rotationally symmetric system), this sets this last thickness to bring the image surface to the point where the marginal ray height is zero. The default height value is zero and the solve will adjust the thickness appropriately" while the EFFL in the first order optical prperties is paraxial. I would suggest to use a fixed thickness and run then run the macro. Please have a look at the help files: Thickness Solves, First-Order Optical Properties.

Kind Regards,

Niki