Safety problems exist where it is necessary to direct electricity into explosive chambers such as aircraft fuel tank gauges. A photonic power circuit has been developed which transmits a laser light over a fiber optic cable to a 40-50 % efficiency gallium arsenide, indium phosphide or indium-gallium arsenide PV array which converts the light to electricity. The transducer then converts the information back to laser light at a different wavelength, which is sent back to the host on the same fiber cable. Estimates indicate the size of the market today is $15 million, but this number could rise to hundreds of millions in the future.
IEEE Spectrum, October 2005, p. 18