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Annular Axial lens

  • February 8, 2021
  • 1 reply
  • 437 views

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Hi,

I'm using the non-squential component editor and trying to create a window with a central hole using the Annular Axial Lens. The outside semi-diameter is 18mm and the hole semi-diameter is 1.5mm. It's not clear from the manual how the parameters Aperture, Revolution and (possibly) Decentre relate to these diameters. I have tried every combination of the numbers 1.5, 18 and 16.5 (the difference) in those parameters and none produce the desired result.

Thanks for any help.

1 reply

Berta.Bernad
Zemax Staff
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  • Zemax Staff
  • February 8, 2021

Hi Nick,

The annular axial lens is defined by sweeping the cross section of a bi-aspheric lens around a decentered axis parallel to the axis of symmetry of the cross section. So you will need to set the radial aperture of the cross section as (18-1.5)/2 =8.25  and the revolution parameter ( the radius of rotation from the local Z axis to the axis of symmetry of the cross section)  as 8.25+1.5= 9.75:

To model a lens with a hole it's probably easier to use two lenses and use the nesting rule (If a ray strikes more than one object at the exact same point in space; the last object listed in the NSC Editor determines the properties of the surface or volume at that point.) You can check a sample file (lens with hole.zmx) in the folder \Zemax\Samples\Non-sequential\Miscellaneous

Best,

Berta