A quasilinear wide-range radiometer amplifier implemented with correlated phase-sensitive detection

Sen-Yen Shaw, Yu-Wei Hsiao
1999 Review of Scientific Instruments  
A radiometer amplifier capable of wide-range optical measurement is described. Based on a novel automatically ranged electrometer and amplifier circuit, the radiometer provides a quasilinear analog output for the measurement of input radiation over ten orders of magnitude. Together with the scheme of phase-sensitive detection of modulated optical signals, the circuit resulted in an output voltage of low noise and offset drift. It can be applied directly to various kinds of photodetectors. The
more » ... otodetectors. The application of standard integrated circuits and lock-in amplifiers makes the whole system low cost and it can be readily built.
doi:10.1063/1.1149787 fatcat:aisnrbv5cjb5phzsw3gdakam7i