INFRARED FILTERS FOR HIGH-EFFICIENCY THERMOVOLTAIC DEVICES

Three different infrared filter designs are described for application in high-efficiency thermovoltaic power systems. They are two-dimension al periodic grid arrays with square-loop, circular-loop, or cross aper ture (or slot) elements printed on thin dielectric films. These three filters' bandpass performances are demonstrated to transmit the wavele ngth that can be efficiently converted to electricity, and to reflect other wavelengths back to the heat source, hence conserving energy and increasing the power system's efficiency. The design with cross slot elements exhibits the highest Q bandpass property (or the fastest cuto ff for out-of-band wavelength). (C) 1997 John Wiley & Sons, Inc.