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US4631402A
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Optical electric-field measuring apparatus
Assignee: Hitachi Cable Ltd
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Filing: 1984-02-01
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Granted: 1986-12-23
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Expires: 2004-02-01
Abstract
Abstract An apparatus for measuring electric field by making use of electrooptic effect includes an electrooptical crystal having a crystallographically eulytite structure such as Bi 4 Ge 3 O 12 , Bi 4 Si 3 O 12 or Bi 4 (Ge, Si) 3 O 12 as a material with electrooptic effect. The optical electric-field measuring apparatus has an increased measuring sensitivity and a stabilized temperature characteristic and scarcely disturbs the distribution of electric field to be measured.
Inventors
- 👤 Kazuyuki Nagatsuma
- 👤 Kazumasa Takagi
- 👤 Hiroyoshi Matsumura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 13:13
CPC Classifications
G; G01; G01R; G01R29/00; G01R29/08; G01R29/0864; G01R29/0878; G01R29/0885; G01R29/12; G02; G02F; G02F1/00; G02F1/01; G02F1/03
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
194 words
An optical electric-field measuring apparatus, comprising a light source part, an electric-field sensing part including a material with electrooptic effect for varying intensity of light produced by said light source part in correspondence with intensity of an electric field to be measured, a measuring part for measuring intensity of light output from said electric-field sensing part, and light transmission paths for optically coupling said light source part, said electric-field sensing part and said measuring part, wherein at least one electrooptical crystal element arrayed along the light traveling direction having a crystallographically eulytite structure and belonging to a point group 43 m is used as said material with electrooptic effect, and wherein said at least one electrooptic crystal element having a crystallographically eulytite structure and belonging to a point group 43 m has an effective whole length within said at least one electrooptic crystal as measured in the light traveling direction that is greater than a common length at which the same modulation degree is produced when using an electrooptical crystal having a crystallographically eulytite structure and belonging to a point group 43 m and when using an electrooptical crystal belonging to point group 23.
Claim 2
Dependent Claim
194 words
An optical electric-field measuring apparatus, comprising a light source part, an electric-field sensing part including a material with electrooptic effect for varying intensity of light produced by said light source part in correspondence with intensity of an electric field to be measured, a measuring part for measuring intensity of light output from said electric-field sensing part, and light transmission paths for optically coupling said light source part, said electric-field sensing part and said measuring part, wherein at least one electrooptical crystal element arrayed along the light traveling direction having a crystallographically eulytite structure and belonging to a point group 43 m is used as said material with electrooptic effect, and wherein said at least one electrooptic crystal element having a crystallographically eulytite structure and belonging to a point group 43 m has an effective whole length within said at least one electrooptic crystal as measured in the light traveling direction that is greater than a common length at which the same modulation degree is produced when using an electrooptical crystal having a crystallographically eulytite structure and belonging to a point group 43 m and when using an electrooptical crystal belonging to point group 23.
Claim 3
Dependent Claim
28 words
An optical electric-field measuring apparatus according to claim 1, wherein said electric-field sensing part includes a plurality of said electrooptical crystal elements arrayed along the light traveling direction.
Claim 4
Dependent Claim
29 words
An optical electric-field measuring apparatus according to claim 1, wherein light supplied from said light source travels reciprocatingly at least once within said at least one electrooptical crystal element.
Claim 5
Dependent Claim
54 words
An optical electric-field measuring apparatus according to claim 1, wherein said at least one electrooptical crystal element having a crystallographically eulytite structure is at least one selected from the group consisting of Bi 4 Ge 3 O 12 , Bi 4 Si 3 O 12 and Bi 4 (Ge, Si) 3 O 12 .
Claim 6
Dependent Claim
29 words
An optical electric-field measuring apparatus according to claim 1, wherein the whole length of the effective optical path within said electrooptical crystal is at least equal to 5.4 mm.
Claim 7
Dependent Claim
23 words
An optical electric-field measuring apparatus according to claim 1, wherein a direction of said electric field is parallel to said light traveling direction.
Claim 8
Dependent Claim
23 words
An optical electric-field measuring apparatus according to claim 2, wherein a direction of said electric field is parallel to said light traveling direction.
Claim 9
Dependent Claim
23 words
An optical electric-field measuring apparatus according to claim 3, wherein a direction of said electric field is parallel to said light traveling direction.
Claim 10
Dependent Claim
23 words
An optical electric-field measuring apparatus according to claim 4, wherein a direction of said electric field is parallel to said light traveling direction.
Claim 11
Dependent Claim
23 words
An optical electric-field measuring apparatus according to claim 5, wherein a direction of said electric field is parallel to said light traveling direction.
Claim 12
Dependent Claim
23 words
An optical electric-field measuring apparatus according to claim 1, wherein a direction of said electric field is perpendicular to said light traveling direction.
Claim 13
Dependent Claim
23 words
An optical electric-field measuring apparatus according to claim 2, wherein a direction of said electric field is perpendicular to said light traveling direction.
Claim 14
Dependent Claim
23 words
An optical electric-field measuring apparatus according to claim 3, wherein a direction of said electric field is perpendicular to said light traveling direction.
Claim 15
Dependent Claim
23 words
An optical electric-field measuring apparatus according to claim 4, wherein a direction of said electric field is perpendicular to said light traveling direction.
Claim 16
Dependent Claim
23 words
An optical electric-field measuring apparatus according to claim 5, wherein a direction of said electric field is perpendicular to said light traveling direction.
References Cited (Backward Citations)
GB2068137A
Cited
EP0083196A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-12-22 | 1990-06-23 | 1990-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-22 | 1994-06-23 | 1994-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-22 | 1998-06-23 | 1998-12-23 | $7700.00 | Window Closed / Lapsed |