Bolometer

Bolometer Points : Bolometer, Definition, What do you mean by a Bolometer Basically a bolometer is a thermal radiation receiving element. A bolometer is a thermal device that changes its electrical resistance with temperature. The resistance of the bolometer changes in response to the thermal radiation focussed on it. A bolometer is made of thin ribbon or platinum or nickel depending upon the response required. The change in resistance is measured by a Wheatstone bridge. In fact two thin strips are used which form two arms of a other strip is shielded and compensates for any change in ambient temperature. Absorption of radiant thermal energy by the exposed strip results in increase of resistance of the strip which is measured by the bridge calibrated in terms of temperature. Bolometers have a fast response but they are expensive to construct and are less rugged than other detectors.