Instrumentation for Infrared Astronomy

Over the last 10 years infrared astronomy from 2 µm to 1000 µm has blossomed into a major field of observational astrophysics. This development would have been impossible without two major technical advances. , extremely sensitive detectors have been developed and become available for astronomical applications. As detector sensitivity increased, the new astrophysical problems that could be explored as a consequence on concomitant instrument sophistication. Secondly, and also motivated by the first development, major groups have expended much in building and operating telescopes above most or all of the earth's atmosphere, in order to circumvent its opacity and emission throughout range. As wavelengths longer than 30 µm became available to observers, it became clear (cf the review article by Neugebauer, Becklin & Hyland 1971) that many sources are unexpectedly bright in that previously wavelength region. This also provided impetus to improve the selection of available instrumentation.