The view from above the setup:
+------------------------------+
| |
| Mirror |
| |
| ....... |
| ...... ...... |
+..... ^ .....+
|
C e n t e r
o f
C u r v a t u r e
|
+---------------------+---- Equal distance
| | |
V | V
v
Knife Edge ==========> +========><=========+<- Slit
Mounted on | **** |<- Glass ground with #120
Lathe bed | |
+-------+ | ^^ |
| | | || |
"|=======| | Light source | (Halogen bulb)
8mm Movie camera"| | | |
Zoom lens ---> "| | +----Aluminum Foil--+
"|=======| Box
"| |
"+--...--+
Tripod mount + "
-------> + " ^^^ <--- CCD Array
" ||| <--- CCD Array leads
"+-------+
"| | <--- CCD Camera body
"+- ----+
" ""
" ""
" ""
Aluminum plate->" ""
" ""
""
"" <---- Wire to IBM PC computer card
The 8mm Movie camera Zoom lens has several air-spaced element groups which are all exposed to the room lighting.
The CCD array is also exposed to the room lighting, so I can only use this at night with the room lights out.
I turn the PC's CRT away from the setup, and keep the brightness down so it won't interfere either.
When everything gets proven, and clean, I'll wrap the camera in aluminum foil, and tape it shut so I can use it in the daytime.
The camera and lens do not move with the knife edge.
The lens is focused at ten feet which is my radius of curvature.
Every time I re-mount my mirror after polishing, I need to reposition the camera to get a good image since the reflected image of the light source moves around when I take the mirror away, and then put it back.
-Alan Kilian