EP0188919A1
Expired / Lapsed
EP
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A method for the formation of a diffraction grating
Assignee: Sharp Corp
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Filing: 1985-12-23
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Granted: —
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Expires: 2005-12-23
Abstract
Abstract A method for the formation of a diffraction grating on a substrate using a holographic technique and an etching technique, wherein the periodicity of the pattern of the diffraction grating is changed at will by a change of the light-path length of one of the two light fluxes from a holographic exposing system.
Inventors
- 👤 Toshihiko Yoshida
- 👤 Harushisa Takiguchi
- 👤 Shinji Kaneiwa
- 👤 Sadayoshi Matsui
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 14:04
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/10; H01S5/12; G; G02; G02B; G02B5/00; G02B5/18; G02B5/1847; G02B5/1857; G02B5/32; G02B6/00; G02B6/10; G02B6/12; G02B6/122; G02B6/124; H01S5/124; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
53 words
A method for the formation of a diffraction grating on a substrate using a holographic technique and an etching technique, wherein the periodicity of the pattern of the diffraction grating is changed at will by a change of the light-path length of one of the two light fluxes from a holographic exposing system.
Claim 2
Independent Claim
53 words
A method for the formation of a diffraction grating on a substrate using a holographic technique and an etching technique, wherein the periodicity of the pattern of the diffraction grating is changed at will by a change of the light-path length of one of the two light fluxes from a holographic exposing system.
Claim 3
Dependent Claim
45 words
A method for the formation of a diffraction grating according to claim 1, wherein the change of the light-path length of one of the two light fluxes from the holographic exposing system is.achieved by passing said light flux through a transparent board of uneven thickness.
Claim 4
Dependent Claim
46 words
A method for the formation of a diffraction grating according to claim 2, wherein the difference Ad in thickness between the thicker portion and the thinner portion of said transparent board has the following relationship to the wavelength of the light passing through said transparent board:
Claim 5
Dependent Claim
36 words
A method for the formation of a diffraction grating according to claim 3, wherein the width of the thicker portion of said transparent board is equal to that of the thinner portion of said transparent board.
Claim 6
Dependent Claim
50 words
A method for the formation of a diffraction grating according to claim 4, wherein the width of both the thicker portion and the thinner portion of said transparent board is equal to the length of a semiconductor laser resonator which is obtained using the substrate having said diffraction grating thereon.
References Cited (Backward Citations)
DE1094484B
Cited
US4402571A
Cited
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