Spectral channel demultiplexer utilizing a planar multimode waveguide

The technology of fabrication of glass planar multimode waveguides with a guiding layer a few tens of microns thick was mastered. Such waveguides should find use in various integrated-optics components of fiber-optical communication lines employing multimode fibers. A waveguide of this type was used to construct a channel demultiplexer with a holographic concave diffraction grating designed for lines with spectral channel multiplexing in multimode or single-mode fiber waveguides. The reciprocal linear dispersion of this demultiplexer was 43 nm/mm and the crosstalk level was less than 15 dB (measured in terms of the optical power) after demultiplexing of channels for monochromatic carriers separated by spectral intervals of 43 nm.