Re: software for measurements from video images?

[brian whatcott <inet@intellisys.net>]

At 22:38 10/24/97 -0400, you wrote:
> ...
> can you explain just how your references describe the timing
> during exposure and recording;  the reference you cite is not readily
> available.
> ...
> Bob Sciamanda	

My references at hand do not include detailed timing arrangements for a CCD
readout.
 The Illustrated Encyclopedic Dictionary of Electronics, (Douglas-Young,
Parker Publishing NY) offers a diagram and paragraph on CCDs which
describes a doped silicon substrate of either but say n-type.

This is covered by a layer of SiO2, which is in turn covered by a
close-spaced row of aluminum electrodes. Gaps in the SiO2 allow a diffused
p type diode patch
(Which can be a photodiode, I'd think)

 The aluminum electrodes are driven with three phases of increasing
negative voltage. A 'potential well' is produced beneath each electrode of
'depth' proportional to the magnitude of the voltage. This sweeps any
positive charge carriers in integrated storage at the diode junction into
the deeper well. The charge is carried in this way to adjacent wells of
increasing depth.

 I conclude that this provides a way of 'occulting' a photocharge from a
diode into a storage channel, which may shift, bucket-brigade style to an
output, or alternatively may dump unwanted charge elsewhere.
 I strongly suspect that the CCD shift register geometry is in the form of
a field scan pattern.

Hope this hand-waving helps.

Brian
brian whatcott <inet@intellisys.net>
Altus OK