Hi Amit,

Are you getting the same result when looking at the 1D MTF window?

Are you using any Vignetting or different weight for the fields?

If you can share your file it will be easier to help.

Best regards,

Nadav

Is your field curved and you happen to be at best focus at the FOV edge?  Did you weight the FOV edge unusually high prior to optimization?  

Hello Nadav,

unfortunately due to a non-disclosure I would not be able to share the file.

I looked at the 1D MTF data and it shows the same thing. Closer to the optics axis, the MTF (average of Tan and Sag) is very bad and improves as it moves towards higher FOV.

So the lens is a fisheye 120° FOV lens with high distortion. The way I have set up my FOV is  through a grid of points (because I wanted to evaluate the PSF over the entire FOV to correlate the results of Image Simulation).

However, all the points on the FOV have the same weight of 1. And no vignetting.

Best,

Amit

Hi Mike,

good question about the optimization. Although the optimization was not run after the new “grid field” was set up, running a new optimization resulted in minimal change of the results. The MTF decreased a little more near the optical axis but the overall pattern remains the same. The MTF is still less at lower field angles and gets better at higher field angles. All the field points have the same weight.

Best,

Amit

Hi Amit,

Thanks for sharing. 

I think you need only quarter of the fields points due to the symmetry of the problem.

Maybe when you deifne it like you did  each field is weight 4 times than the center.