An Infrared Camera for Leuschner Observatory and the Berkeley Undergraduate Astronomy Lab
We describe the design, fabrication, and operation of an infrared camera which is in use at the 30 inch telescope of the Leuschner Observatory. The camera is based on a Rockwell PICNIC 256x256 pixel HgCdTe array, which is sensitive from 0.9 to 2.5 mm. The primary purpose of this telescope is for undergraduate instruction. The cost of the camera has been minimized by using commercial parts wherever practical. The camera optics are based on a modified Offner relay which forms a cold pupil where stray thermal radiation from the telescope is baffled. A cold, six-position filter wheel is driven by a cryogenic stepper motor, thus avoiding any mechanical feedthroughs. The array control and readout electronics are based on standard PC cards; the only custom component is a simple interface card which buffers the clocks and amplifies the analog signals from the array.