Patent US4900134A successfully refreshed from Google Patents.
US4900134A
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US
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Optical device
Assignee: Hitachi Ltd
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Filing: 1987-12-29
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Granted: 1990-02-13
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Expires: 2007-12-29
Abstract
Abstract An optical device having a material exhibits an optical rectification effect is disclosed. The optical device utilizes direct current polarization which is induced in the material by a control light. The induction of the direct current polarization in the material by the control light changes the refractive index and absorption spectrum of the material. This is based on the so-called electrooptic effect and Franz-Keldysh effect. The present invention provides the optical device according to which external incident light can be modulated at high speed with the control light by utilizing the change of the refractive index or the change of the absorption spectrum.
Inventors
- 👤 Hiroaki Inoue
- 👤 Toshio Katsuyama
- 👤 Hiroyoshi Matsumura
- 👤 Shinji Sakano
- 👤 Hitoshi Nakamura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:51
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/015; G02F1/017; G02F1/01716; B; B82; B82Y; B82Y20/00; G02F1/0126
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
46 words
An optical device comprising: supporting means; and modulation means, supported by said supporting means, having an optical rectification material which is polarized by a control light, wherein said optical rectification material has an excitonic absorption wavelength which is smaller than the wavelength of said control light.
Claim 2
Dependent Claim
46 words
An optical device comprising: supporting means; and modulation means, supported by said supporting means, having an optical rectification material which is polarized by a control light, wherein said optical rectification material has an excitonic absorption wavelength which is smaller than the wavelength of said control light.
Claim 3
Dependent Claim
25 words
An optical device as claimed in claim 1, wherein said optical rectification material has its refractive index and absorption spectrum changed by said control light.
Claim 4
Dependent Claim
16 words
An optical device as claimed in claim 1, wherein said supporting means is a semiconductor substrate.
Claim 5
Dependent Claim
39 words
An optical device as claimed in claim 1, wherein said modulation means is made of at least one of materials selected from the group consisting of Si, GaAs, InP, InGaAs, InAlAs, InGaAsP, ZnTe, ZnS, ZnSe, CdTe, CdS and CdSe.
Claim 6
Dependent Claim
99 words
An optical device comprising: a semiconductor substrate; semiconductor layers formed on said semiconductor substrate, having an optical rectification layer which is polarized by a control light, wherein said optical rectification layer has an excitonic absorption wavelength which is smaller than the wavelength of said control light; a first surface of said semiconductor layers which accepts said control light; a second surface of said semiconductor layers which accepts incident light that is modulated at said optical rectification layer by said control light; and a third surface of said semiconductor layers which delivers output light that is the modulated incident light.
Claim 7
Dependent Claim
99 words
An optical device comprising: a semiconductor substrate; semiconductor layers formed on said semiconductor substrate, having an optical rectification layer which is polarized by a control light, wherein said optical rectification layer has an excitonic absorption wavelength which is smaller than the wavelength of said control light; a first surface of said semiconductor layers which accepts said control light; a second surface of said semiconductor layers which accepts incident light that is modulated at said optical rectification layer by said control light; and a third surface of said semiconductor layers which delivers output light that is the modulated incident light.
Claim 8
Dependent Claim
19 words
An optical device as claimed in claim 5, wherein said optical rectification layer has a multiple quantum well structure.
Claim 9
Dependent Claim
19 words
An optical device as claimed in claim 5, wherein said semiconductor layers are made of group-III-V compound semiconductor materials.
Claim 10
Dependent Claim
17 words
An optical device as claimed in claim 5, wherein said optical device has a pair of electrodes.
Claim 11
Dependent Claim
15 words
An optical device as claimed in claim 6, wherein said semiconductor layers have reflecting coatings.
Claim 12
Dependent Claim
13 words
An optical device as claimed in claim 8, wherein said electrodes are transparent.
Claim 13
Dependent Claim
87 words
An optical device comprising: a semiconductor substrate; an optical waveguide formed onm said semiconductor substrate and having selectively actuated optical waveguide paths and a crossing part for said paths; and an optical rectification layer formed at said crossing part so as to switch light traversing along one of said optical waveguide paths into another optical waveguide path of said optical waveguide in response to a control light, wherein said optical rectification layer has an excitonic absorption wavelength which is smaller than the wavelength of said control light.
Claim 14
Dependent Claim
87 words
An optical device comprising: a semiconductor substrate; an optical waveguide formed onm said semiconductor substrate and having selectively actuated optical waveguide paths and a crossing part for said paths; and an optical rectification layer formed at said crossing part so as to switch light traversing along one of said optical waveguide paths into another optical waveguide path of said optical waveguide in response to a control light, wherein said optical rectification layer has an excitonic absorption wavelength which is smaller than the wavelength of said control light.
Claim 15
Dependent Claim
23 words
An optical device according to claim 11, wherein said optical rectification layer has at least its refractive index changed by said control light.
Claim 16
Dependent Claim
21 words
An optical device according to claim 12, wherein said optical rectification layer is made of group - III-V compound semiconductor materials.
Claim 17
Dependent Claim
18 words
An optical device according to claim 13, wherein said optical rectification layer has a multiple quantum well structure.
Claim 18
Dependent Claim
27 words
An optical device according to claim 14, wherein said multiple quantum well structure is comprised of a plurality of vertically stacked layers each of about 100Å thick.
Claim 19
Dependent Claim
36 words
An optical device according to claim 14, wherein said multiple quantum well structure is comprised of a plurality of vertically stacked layers, each one having a thickness of at least 100Å but not greater than 200Å.
Claim 20
Dependent Claim
63 words
An optical device according to claim 14, wherein said multiple quantum well structure is an undoped structure which consists of vertically stacked layers sandwiched between a pair of undoped layers which are in turn respectively stacked with a highly-doped arsenide outer layer, one such outer layer being a highly-doped p + layer and the other outer layer being a highly-doped n + layer.
Claim 21
Dependent Claim
27 words
An optical device according to claim 17, wherein said multiple quantum well structure is comprised of a plurality of vertically stacked layers each of about 100Å thick.
Claim 22
Dependent Claim
37 words
An optical device according to claim 17, wherein said multiple quantum well structure is comprised of a plurality of vertically stacked layers, each one having a thickness of at least 100Å but not greater than 200 Å.
Claim 23
Dependent Claim
21 words
An optical device according to claim 1, wherein said optical rectification material has its refractive index changed by said control light.
Claim 24
Dependent Claim
21 words
An optical device according to claim 1, wherein said optical rectification material has its absorption spectrum changed by said control light.
Claim 25
Dependent Claim
27 words
An optical device according to claim 6, wherein said multiple quantum well structure is comprised of a plurality of vertically stacked layers each of about 100Å thick.
Claim 26
Dependent Claim
36 words
An optical device according to claim 6, wherein said multiple quantum well structure is comprised of a plurality of vertically stacked layers, each one having a thickness of at least 100Å but not greater than 200Å.
Claim 27
Dependent Claim
63 words
An optical device according to claim 6, wherein said multiple quantum well structure is an undoped structure which consists of vertically stacked layers sandwiched between a pair of undoped layers which are in turn respectively stacked with a highly-doped arsenide outer layer, one such outer layer being a highly-doped p + layer and the other outer layer being a highly-doped n + layer.
Claim 28
Dependent Claim
27 words
An optical device according to claim 24, wherein said multiple quantum well structure is comprised of a plurality of vertically stacked layers each of about 100Å thick.
Claim 29
Dependent Claim
36 words
An optical device according to claim 24, wherein said multiple quantum well structure is comprised of a plurality of vertically stacked layers, each one having a thickness of at least 100Å but not greater than 200Å.
Claim 30
Dependent Claim
23 words
An optical device according to claim 26, wherein each of the outer layers has a thickness substantially between 0.5 μm to 1 μm.
Claim 31
Dependent Claim
23 words
An optical device according to claim 25, wherein each of the outer layers has a thickness substantially between 0.5 μm to 1 μm.
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