Abstract: An infrared radiation detector device has a cooled detector element (3) within a first optical device (internal cold shield (1.sub.i)). The first optical device includes a first diaphragm (6.sub.i) in front of said detector element. The infrared radiation detector device has a second optical device (external cold shield (1.sub.a)) which is thermally separated from the first optical device. The second optical device includes a second diaphragm (6.sub.a). The aperture (7.sub.a) of the diaphragm forms the pupil of the infrared optic which produces an infrared image on the surface of said detector element (3).

Abstract: The invention relates to an infrared objective (IR objective) with a lens arrangement for the production of an infrared image on a detector element of infrared detector equipment. In this respect it may be a question of a focal plane array (FPA) within a Dewar vessel with an internal cold shield for substantially preventing access of thermal radiation from the surroundings (spurious light fractions). The internal cold shield is placed behind an external uncooled cold shield comprising several staggered external cold diaphragms.