Metallic bolometers in periodically interrupted radiation

Abstract

A theory of metallic bolometers is given for the case that the measured radiation is periodically interrupted. The impedance of a bolometer through which a direct and an alternating current simultaneously flow, is derived generally. Separate solutions are given for bolometers cooled by heat conduction and bolometers with thermal impedance dependent on the temperature. Expressions are derived for the sensitivity and minimum measurable power and the conditions for the choice of a coupling transformer with optimum ratio. In conclusion the lowest value of the minimum power at all measurable by metallic bolometers working in interrupted radiation is determined.