Showing papers on "Wavelength-division multiplexing published in 1979"

Optical multiplexer and demultiplexer

Abstract: An optical multiplexer and/or optical demultiplexer for multiplexing and/or demultiplexing a plurality of wavelengths comprises a plurality of optical filters each of which transmits a predetermined wavelength and reflects other wavelengths, said optical filters being arranged so that an optical beam is transmitted or reflected via each optical filter in sequence in a zigzag fashion. A light source or light detector is provided behind each optical filter to project or receive a collimated optical beam. The angle of incidence when a beam is applied to an optical filter is small. And, another optical means is provided to connect the present optical multiplexer and/or demultiplexer with an outside optical fiber. The transmission wavelength of each optical filter is different from the others.

Wavelength selective optical coupler

Abstract: An optical coupler for a fiber optic communication system, which couples one band of wavelengths out of the fiber while allowing others to be carried further. This allows wavelength division multiplexing of different signals within a single fiber. The preferred embodiment of the invention is comprised of a waveguide having aperiodic corrugations in one wall and a Fabry-Perot type resonator enclosing the waveguide around the corrugations with its axis transverse thereto.

Optical demultiplexer for a wavelength division multiplexing system

Abstract: A wavelength division multiplexing (WDM) technique, which transmits signals with different wavelengths by means of a single optical fiber, can increase the capacity of optical fiber transmission systems. This paper describes the experimental results of a demultiplexer using a diffraction grating for a WDM system. The insertion loss of the demultiplexer could be decreased by using a large core output fiber, an Au-coated diffraction grating, and small aberration lenses. There were five channels in the 0.8-μm wavelength region. Wavelength spacing was 200 A. Insertion loss for each channel was about 2 dB, and cross talk was <−30 dB.

Low-loss optical demultiplexer for WDM systems in the 0.8-μm wavelength region

Abstract: A low-loss small-sized demultiplexer using a diffraction grating in the Littrow mounting is realized for a wavelength division multiplexing (WDM) system for optical fiber systems. The system has five channels and a wavelength spacing of 200 A in the 0.8-μm region. Insertion loss was about 1.7 dB in each channel, and cross talk was <−30 dB. These characteristics make this demultiplexer the most suitable device available for optical fiber systems employing WDM configurations.

Dual-wavelength demultiplexing InGaAsP/InP photodiode

Abstract: Most of the work on lightwave systems has concentrated on coupling a single source to a fiber and, hence, transmission of a singlewavelength band. The information capacity of these systems could be increased, however, by combining signals from sources emitting at different wavelengths, i.e., wavelength-division multiplexing.1 This approach, however, will require demultiplexing the different wavelength channels at the receiver. In this talk we describe a new photodiode structure capable of both detecting and demultiplexing two wavelength bands simultaneously.