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Hi everyone,

Is there a standard way to generate the longitudinal PSF (ie. intensity cross section in the y-z plane) of a focusing lens? I’ve done this two ways, which have similar, but somewhat different results, and want to make sure to use the best method going forward.

  1. Recording the Huygens Cross Sectional PSF in the image x-y plane when in focus and combining the result with the PSF plots as the image plane is defocused.
  2. Adding a co-ordinate break just prior to the image plane and rotating the coordinate system by 90 degrees around the y-axis prior to calculating the Huygens Cross Section PSF.

 

Thanks,

I think a 3D PSF is best constructed from a stack of 2D slices (your method 1).  The second approach, in which the image plane is rotated by 90 degrees, is an attempt to use the standard 2D PSF analysis in way that it is not really designed to accommodate.  I understand the concept behind trying this method, but when I implemented the Huygens version with a diffraction-limited asphere, I got only zeros (i.e., no PSF whatsoever), which is kind of what I expected.  So, I’m a bit surprised that you were able to get anything meaningful with your second approach.

 


Thanks for the response Jeff. It makes sense to use the approach of stacking 2D slices, as the Huygens PSF analysis is being used the way it was designed to be used.

I played around with the Huygens PSF analysis on a diffraction-limited asphere to replicate your result of getting only zeros. Sure enough I got zeros when tilting the coordinate break by 90 degrees, at 89.9 degrees I got a PSF, or alternatively when adding a material to the image plane I also got a PSF even at a tilt of 90 degrees. In my case, I have water as the image plane’s material as my lens design is a water dipping objective, which resulted in a PSF being generated.


Just as a quick follow-up, here’s a publication in which 3D PSFs were generated using Huygens analysis (presumably a stack of 2D PSFs):  Reflecting objective microscope system

 

 

 


One of our former colleagues has also posted an API solution here: https://www.linkedin.com/feed/update/urn:li:activity:6821892533598203904/

 


I have posted @Michael.Humphreys solution on our Code Exchange: 

 


Hi Christoph,

Could you give more details on how you defocused the image plane and combine the Huygens Cross Sectional PSF results if you don’t mind?

Thank you,

Regards,

Marzanna

 


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