Measuring of the factor of absorption efficiency of thinwire bolometer

Abstract

Absolute measurements of laser radiation energy parameters with thin-wire bolometers require known factors of absorption efficiency (FAE) of bolometer for E- and H-polarization state of radiation, and also coefficient of dichroism of radiation. In the work the method of measuring of FAE of bolometer is grounded and checked for platinum bolometer and radiation on wavelength 1.06 /spl mu/m. Beam of continuous laser radiation with fixed polarization state is scanned in cross-section with bolometer. The relative average and maximal values of radiation intensity, beam-wide which passes through more than 99% of radiation intensity are determined via obtained profile distribution of radiation intensity. The absolute value of laser power is measured. The absolute average value of profile distribution of radiation intensity is determined with known values of laser power and beam wide. The absorbed power of radiation is measured in some point of profile distribution e.g. in maximum. In this point the incident on the bolometer power is determined with average absolute value of profile distribution, ratio of maximal to average values of profile relative distribution and bolometer diameter. The ratio of absorbed power to incident one gives FAE of bolometer. The analysis of errors of obtained measuring results is carried out.