The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 11, 2003
Filed:
Nov. 27, 2000
Sumitomo Electric Industries, Ltd., Osaka, JP;
Abstract
The present invention relates to a method of making a diffraction grating device, in which an optical waveguide is irradiated, by way of a phase grating, with light capable of inducing a refractive index modulation in an optical waveguide region of the optical waveguide so as to form a diffraction grating in the optical waveguide region. In the present invention, when modulating the refractive index of the optical waveguide region of an optical fiber, the intensity of refractive index modulation inducing light emitted from a laser light source so as to irradiate the phase grating is adjusted according to individual positions on the phase grating. Alternatively, the scanning speed of a mirror scanned by a stage is adjusted according to the individual positions on the phase grating. Here, the amount of irradiation of refractive index modulation inducing light at each position on the phase grating is adjusted so as to cancel the diffraction efficiency distribution of phase grating. The present invention can make a diffraction grating device having a desirable characteristic even when the diffraction efficiency distribution of phase grating deviates from its desirable distribution.