75904487
Jan 28, 2000
Optical frequency band extraction devices, namely, light emitting diodes, photo-diodes, phototransistors, optical multiplexers, optical demultiplexers, wavelength division multiplexers and demultiplexers, dense wavelength division multiplexers and demultiplexers, charged coupled devices, optical-to-electrical converters and electrical-to-optical converters and photo-detectors
Electrical and Scientific Apparatus