Re: OFF TOPIC: Beginner could use some direction
| Subject: | Re: OFF TOPIC: Beginner could use some direction |
| From: | James W. Burrows |
| Date: | Wed Apr 03 22:04:33 1996 |
> >If your exit pupil is smaller than 1 mm, diffraction starts to kill the
> >image...
>
> Why is that?
I probably should go down stairs and grab the college physics text and
see how wide the diffraction pattern is for a given pinhole (Ive
forgotten whether its Fraunhofer or Fresnel). Its easier to form a 1
mm or smaller pinhole with your thumb and two fingers and look through it
at a distant street light. Squeeze down to make the pinhole smaller and
watch the light turn into a big fuzzy ball - thats what happens to all
points in your image when you try to squeeze the light through a small
exit pupil.
I believe theres some correlation between the size of ones pupil and
the separation between the rods and cones on the retina: excellent
design (evolution or God? - your choice).
Jim Burrows
JD2450177
