View single post by jk
 Posted: Sun Jun 16th, 2019 17:36
jk



Joined: Mon Apr 2nd, 2012
Location: Carthew, Cornwall, United Kingdom
Posts: 6874
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I think I understand what they are talking about now.

Simple description of situation is......
Each photo-site has a micro-lens on its surface and you want to optimise light entry into the photo-site well.
To optimise the light entry to the photo-site ideally you want light to hit vertically but it has a curved surface to allow light at the edges as well as the centre to get to the bottom of the well of the photo-site. This is a practical/pragmatic design issue resolution. Otherwise you would need an infinitely wide camera lens throat to have vertical entry into the photo-site.
However the bigger the lens throat the easier the lens design is as you dont have to refract the light so much to reach different parts of the sensor to be vertical to the micro-lens surface.
Value Angle is the amount of diffraction needed to give near equal light for the edge photo-sites compared to the centre photo-sites.



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Still learning after all these years!
https://nikondslr.uk/gallery_view.php?user=2&folderid=none