Title:
【発明の名称】回折格子
Document Type and Number:
Japanese Patent JPH0830763
Kind Code:
B2
Abstract:
PURPOSE:To realize a diffraction grating which has a flat surface applicable to a semiconductor laser by providing the sections exposed with plural layers of different refractive indices formed periodically on a substrate as a surface. CONSTITUTION:The sections of the layers 2, 3 grown to multiple layers by alternately growing the crystals of AlxGa1-xAs layers 2 and AlyGa1-yAs layers 3 on the flat GaAs substrate 1, then subjecting the layers to diagonal polishing are exposed on the surface. Part of incident light penetrates from the surface into the layers 2 and 3 when the incident light enters the diagonally polished surface in parallel therewith. Said light is, therefore, reflected near the part where the refractive index changes, i.e., the boundary faces of the layers 2 and the layers 3. Since the refractive index changes periodically, the Bragg reflections by which the phases of the reflected light are unified are generated and the diffracted light is obtd. This diffraction grating has the flat surface and, therefore, the thermal decomposition of the diffraction grating and the collapse of the rugged shape and the consequent annihilation of the diffraction grating are obviated even when exposed to a high temp.
Inventors:
Takashi Murakami
Application Number:
JP24844187A
Publication Date:
March 27, 1996
Filing Date:
October 01, 1987
Export Citation:
Assignee:
Mitsubishi Electric Corporation
International Classes:
G02B5/18; G02B6/122; H01S5/12; H01S5/125; (IPC1-7): G02B5/18
Domestic Patent References:
| JP622207A | ||||
| JP54106525A |
Attorney, Agent or Firm:
Takada Mamoru
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