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Question

Surface Accuracy/Irregularity

  • December 29, 2023
  • 1 reply
  • 127 views

Hello, For spherical lenses, how do we calculate Irregularity (P-V) and Power (P-V) as number of rings/fringes?

For example, how is λ/4 P-V surface = 0.5 fringe?

Thank you

1 reply

Christian Zimmermann

Hello Elsa,

I think this is due to definition of “Double Pass Fringes” instead of “Single Pass Fringes”.

https://telescope-optics.net/testing_optical_quality.htm

Kind regards,

Christian