A Thin-Film Bolometer Unit

The bolometer unit widely used for measuring microwave and millimeter wave power becomes more difficult to construct and obtain good performance, as the wavelength gets shorter. To overcome these difficulties, a new unit has been developed which has a very simple structure by virtue of a new matching procedure. The bolometer element is made of a thin metal film evaporated on a thin mica substrate, and its mount consists only of a short circuit and a flange. Experimental units have been designed at 35 GHz and 10 GHz, and these have demonstrated excellent characteristics, such as high efficiency, low VSWR, wide bandwidth, high power handing capacity, etc. The thermistor units applying the same matching theory are also investigated at 35 GHz and 50 GHz.