Fig. 9From: Mixed-gas CH4/CO2/CO detection based on linear variable optical filter and thermopile detector arraya Spectral response of thermopile detector. Inset is optical micrographs of the (i) front-side and (ii) backside of the thermopile chip. b Thermoelectric characteristics of thermopile detector at different ambient temperatures. Inset is the schematic diagram of measurement setupBack to article page