Re: Astro CCDs still dragging their pixel feet

>
> Cooling a camera is expensive.
when compared with the cost of the sensor the cooling unit is almost
negligible. A water cooled six stage TEC wont cost more than five
hundred including pumps and radiator. TECs cost about $50 per stage.

It requires care in the mechanical design
> to avoid stressing the fragile cooler while getting good thermal
> coupling between the detector and cold side, and the heat dissipator
and
> hot side.
for proper operation the TEC stack needs to be pre loaded to over 100
pounds of force then that assembly needs to attached to the sensor with
less than 10 pounds. with thermal epoxy like arctic silver you can make
a zero force joint between the sensor and TEC stack with over 99%
efficiency.

It also requires a well sealed, dry chamber for the detector
> to prevent dew and frost.
This is little more complicated but it is just a matter of cluing the
chamber shut with RTV and a desiccant.

I admit though this all does cost some money and does not lend itself
to inexpensive cameras.

Ian Anderson
www.customopticalsystems.com

.

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