Plans for Cooling with a Peltier Device and Fan
The results I obtained from my first night out with the uncooled greyscale quickcam leave me with the following thoughts:
Even though the ambient temperature was in the single digits fahrenheit, I don't think the CCD chip was cooled as well as it needs to be. I have no other experience with the greyscale quickcam in warm temperatures so I don't know how less sensitive or more noisy it would be. I have purchased a peltier device and a cooling fan made for the peltier. The peltier can be purchased online at:
Diagram showing typical peltier mounting from Tellurex site.
My plans are to:
1. Remove the CCD chip from the circuit board.
2. Connect it to the circuit board with a ribbon cable(s).
3. Mount the CCD chip on a small aluminum block (cold plate).
4. Mount the CCD chip / aluminum block on the peltier's cold side. Radio Shack thermal paste will be used for all thermal connections.
5. Nylon screws and a small frame will be used to press the CCD chip to the aluminum block and peltier.
6. A small airtight compartment will be made to house the CCD chip and peltier's cold side to prevent condensation from forming on the CCD.
7. A skylight camera filter will be used for the glass pane of the airtight compartment.
8. The peltier's hot side, heat sink and fan will be positioned outside of the airtight compartment.
9. The peltier and fan will be powered by 12V DC. A 12V Dc 2.0 Amp power supply will be used with the peltier. a 12V DC battery will be an optional power source.
10. No control circuit for the peltier will be used other than an on/off switch. This will be done initially as a test and to keep things simple with fingers crossed.
10. A switch will be installed to enable and disable anti-blooming (yellow lead).
11. A T-thread from a camera T-ring will be used for connecting the quickcam housing.
UPDATE 2/3/00: I have completed the cooled greyscale quickcam and assembly steps and photos can be seen by clicking here.
There is much information on peltier devices and thermoelectric cooling at:
For a comparrison of dark current noise at 70 degree Fahrenheit versus 7 degrees Fahrenheit click here
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