The optical imaging TES detector array: Considerations for a cryogenic imaging instrument

A Stanford/NIST collaboration is developing an imaging detector suitable for IR/optical/UV astronomical observations based on the Transition Edge Sensor, a cryogenic quantum microcalorimeter. Currently, the 32 pixel detector can in time and energy resolve single photons with high event rates (Δt<1μs and ΔEFWHM∼0.16eV at 2.33eV and more than 10kHz/pixel). We report on current progress with the first imaging TES instrument, focusing on recent advances in instrumentation including focusing, reflection masking and infrared filtering.