On Mon, 29 Oct 2001 11:41:47 -0500, Peifer, William [OCDUS] wrote: > Maybe someone that knows more about chip fab can >comment on this. Anyway, although each individual pixel may very well be >"looking" through an optic with small numerical aperture, it's only >"looking" a very short distance (microns? tenths of microns?) to the >illuminated spot on the focal plane directly in front of it.
Hmm... I probably need to dig into the real construction of CCD's, but this description of how the 'pixels' read light intensity from a real 'focal plane' in front of them contradicts my own interpretation! You could compare the above description to the focusscreen we all are used to in our SLR viewfinder, but then with a CCD-sensor looking at the matte instead of our eye ... I really don't think it works that way, I think the CCD 'pixels' are very small area's on the CCD surface that build up electric potential when fotons (light) hits them. The fotons could come from any direction, but AFAIK the pixels are 'shielded' from each other in a grid pattern, wich also limits the angle of the incoming light to reach the actual sensor surface ... I tend to think of them as small buckets where the 'sensor' is at the bottom of the bucket. (could be a too simplistic view :-) The sensor surface itself would need to be in the focal plane of the lens being used, I don't see a real image-forming screen here ... Anyone know for sure ? Regards, JvW --------------------------------------------------------- Jan van Wijk; www.fsys.demon.nl - This message is from the Pentax-Discuss Mail List. To unsubscribe, go to http://www.pdml.net and follow the directions. Don't forget to visit the Pentax Users' Gallery at http://pug.komkon.org .
