Wavelength filter with a broad bandwidth of reflection spectrum
US7729053B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 24, 2006 |
| Grant date | Jun 1, 2010 |
| Priority date | — |
| Expiry date | Jun 27, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/285
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A wavelength filter, includes a grating in which a first portion extends in X direction on a substrate surface and a second portion extends in the X direction along the first portion and are alternately arranged in Y direction perpendicular to the X direction on the substrate surface at a constant cycle shorter than a wavelength of light to be used. A cross-sectional figure of respective first portions in the Y direction and perpendicular to the substrate surface is provided with at least one protruding portion so as to have the width in the Y direction wider than neighboring portions. Plural waveguide layers parallel to the substrate surface are divided by regions parallel to the substrate surface. Wavelength bands of light reflected from the plural waveguide layers shift while overlapping with each other to reflect a wavelength band broader than that reflected from a single waveguide layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.