Infrared radiation from a black body is analyzed and used to determine its temperature.
The object is seen in the color of brass.
First, the pressure is reduced by means of a vacuum pump.
The temperature is then reduced with liquid nitrogen.
The black body is then placed in front of the source. The infrared coming from the black body is captured and converted into an electrical signal. This signal can be seen using CRO.
A setup that can be closed and opened in front of the black body source is placed so that all the hot objects emit infrared. When closed, only the background is available.
The one in the picture is in the TIFR DAA lab. In the range of 1-5 micrometers.
Previously used to calculate the temperature of stars and other objects.