To prevent noise due to heat radiation from generating by fitting a cold shield limiting the angle of visibility of an infrared detecting element to a cooling plate fixedly secured to the infrared detecting element and maintained at low temperature.
An infrared detecting element 2 constituted so that the electrode is formed on the side part of the crystal block of a multi-element semicondutor provided, for example, on a sapphire substrate, is fixedly secured to the upper face of a cooling plate 4, and a cold shield 6 for setting the angle of visibility αof the detecting element 2 to be a prescribed value is fitted to the cooling plate 4. For maintaining the cooling plate 4 and the detecting element 2 at low temperature, a Dewar construction having an outer cylinder 10 is adopted, the upper end face of an inner cylinder 8 is fixedly secured to the cooling plate 4, and a cooling device 24 having a cooling part 22 inserted into the inner cylinder 8 is provided. The cold shield 6 has higher thermal conductivity than that of covar as the material of the cooling plate 4, and it is constituted so that three members having circular or rectangular openings are laminated on the cooling plate 4, in order of the member of linear expansion coefficient nearby that of covar.
HIROTA KOJI
WATANABE YOSHIO
UEMURA MASAYO
UEDA TOSHIYUKI
Next Patent: AUTOMATIC FORMING DEVICE FOR TEMPERATURE TABLE FOR INFRARED THERMAL IMAGE DEVICE