Aberration properties in a chirped grating for coarse wavelength division demultiplexing

Hitachi Cable, Ltd., Edo, Tōkyō, Japan
Applied Optics (Impact Factor: 1.69). 09/2006; 45(22):5597-606. DOI: 10.1364/AO.45.005597
Source: PubMed

ABSTRACT We studied the imaging performance of a chirped grating for a demultiplexer designed for coarse wavelength division multiplexing using a wavefront aberration analysis and the ray tracing simulation. The demultiplexer was composed of a chirped grating, cylindrical lenses, and a waveguide. The best image point and the spot shape focused by the chirped grating were effectively calculated with the wavefront aberration. We applied the aberration analysis to design a waveguide to connect branched beams to photodetectors, and we confirmed the demultiplexing performance experimentally.

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