Andor Technology Neo sCMOS, Руководство по оборудованию

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OPERATION
Neo
SECTION 4
Page 73
4.2.2 - TE Cooling
The Neo detector is cooled using a thermoelectric ( TE ) cooler. TE coolers are small, electrically powered
devices with no moving parts, making them reliable and convenient. A TE cooler is actually a heat pump, i.e. it
achieves a temperature difference by transferring heat from its ‘cold side’ (the Neo-chip) to its ‘hot side’ (the
built-in heat sink). Therefore the minimum absolute operating temperature of the Neo sensor depends on the
temperature of the heat sink. Our vacuum design means that we can achieve a maximum temperature
difference of over 60ºC. The maximum temperature difference that a TE device can attain is dependent on the
following factors:
•
Heat load created by the NEO sensor dependant on pixel readout speed
• Number of cooling stages of the TE cooler
•
Operating current
Even with a fan a heat sink typically needs to be at least 10ºC hotter than the air (room) temperature to transfer
heat efficiently to the surrounding air. Therefore the minimum NEO temperature that can be achieved will be
dependent on the room temperature. The table below shows typical minimum detector temperatures when
operating at the different readout speeds and ambient temperatures:
Table 23: Detector cooling temperatures
Minimum detector temperatures
Ambient temperature 200 MHz 400 MHz 560 MHz
20°C air cooled -38 ° C -36 ° C -35 ° C
25°C air cooled -35 ° C -33 ° C -31 ° C
30°C air cooled -30 ° C -29 ° C -27 ° C
35°C air cooled -27 ° C -25 ° C -23 ° C
40°C air cooled -23 ° C -21 ° C -19 ° C
16°C water cooled -46°C -44°C -43 ° C
These are typical figures and will vary from unit to unit, refer to the camera specification sheet for guaranteed
minimum temperature levels and always allow sufficient headroom when conducting experiment to allow for
fluctuations in ambient temperature.
When using water cooling the minimum sensor temperature is no longer dependant on the external ambient but
rather the temperature of the cooled water. Typical figures achieved when cooling using 16°C water are shown
above. When water cooling it is important to always select a water temperature above the dew point to prevent
condensation damage to internal electronics .
Solis provides selectable detector temperature options as follows:
•
-15°C
• -20°C
•
-25°C
•
-30°C
• -35°C
•
-40°C
NOTE: Cooler Off (detector temperature will be stabilized at +26°C)