Vorrichtung zur Messfleckmarkierung bei einem Strahlungsmessgeraet

摘要

In an apparatus for measuring radiation, such as an infrared radiation pyrometer, an opaque patch 30 is illuminated from the rear by a lamp 26 and imaged on to the article under test by a lens 28 to produce a ring 42 of light surrounding a circular target area 24, the radiation from which is focussed onto a detector 14. This arrangement avoids the light from the lamp 26 being reflected to the detector 14 and distorting the measurement. The positioning of the projector system on the optical axis and in the dead angle of a Cassegrain telescope reflector system 12 produces an extremely compact unit. <IMAGE>