Strip of infra-red detectors comprising a cold screen with a constant viewing angle

摘要

The invention uses a strip of infra-red detectors comprising a cold screen of the type that provides a constant viewing angle for all the directors in a direction that is prependicular to the axis of the strip. Two cylindrical mirrors are set at the ends of the strip and placed in the heated part of the cryostat containing the strip and the cold screen. The shape and dimensions of the mirrors as well as their positions are chosen so that the detector placed in the center of the strip detects, through reflection in two mirrors, only cold surfaces while the other detectors detect heated surfaces, through reflection in the two mirrors, in a proportion that increases with distance from the central detector of the strip, so that, along the axis of the strip, every detector has a substantially constant viewing angle. Applications: large-sized strips, for example in space applications.