Patent US5347395A successfully refreshed from Google Patents.
US5347395A
Expired / Lapsed
US
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Optical power limiting device
Assignee: Dornier GmbH
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Filing: 1992-08-06
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Granted: 1994-09-13
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Expires: 2012-08-06
Abstract
Abstract An optical power limiting device whose transmissibility within a wave length range that is of interest is a function of the intensity of the incident radiation, the detuning of the resonance of surface plasmons being utilized. The device is particularly suitable for the protection of IR-detectors against the incidence of high radiation intensities.
Inventors
- 👤 Peter Lautenschlager
- 👤 Werner Scherber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 08:34
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/19; G02F1/195; G02F2203/00; G02F2203/10; G02F2203/52
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
135 words
An optical power limiting device whose transmissibility within a predetermined wave length range is a function of intensity of incident radiation, comprising: a prism having at least one plane boundary surface; two layers, which are applied to the plane boundary surface, one above the other, a first of said two layers being an active layer comprising a material having a dielectric function with a real component that is negative in the predetermined wave length range, and the second of said two layers being a dispersion layer comprising a material having a refraction index in the predetermined wave length range that is strongly dependent on temperature; and means for guiding incident radiation into the prism and onto the plane boundary surface, whereby the dispersion layer is heated in response to increasing intensity of said incident radiation.
Claim 2
Dependent Claim
135 words
An optical power limiting device whose transmissibility within a predetermined wave length range is a function of intensity of incident radiation, comprising: a prism having at least one plane boundary surface; two layers, which are applied to the plane boundary surface, one above the other, a first of said two layers being an active layer comprising a material having a dielectric function with a real component that is negative in the predetermined wave length range, and the second of said two layers being a dispersion layer comprising a material having a refraction index in the predetermined wave length range that is strongly dependent on temperature; and means for guiding incident radiation into the prism and onto the plane boundary surface, whereby the dispersion layer is heated in response to increasing intensity of said incident radiation.
Claim 3
Dependent Claim
21 words
An optical power limiting device according to claim 1, wherein said predetermined wave length range is from 1 to 20 μm.
Claim 4
Dependent Claim
33 words
An optical power limiting device according to claim 1, wherein the active layer (AS) is applied to the plane boundary surface, and the dispersion layer (DS) is applied to the active layer (AS).
Claim 5
Dependent Claim
48 words
An optical power limiting device according to claim 3, wherein the layer thickness of the active layer (AS) is in the range of from 500 nm to 1,500 nm, and the layer thickness of the dispersion layer (DS) is in the range of from 50 to 2,000 nm.
Claim 6
Dependent Claim
33 words
An optical power limiting device according to claim 1, wherein the dispersion layer (DS) is applied to the plane boundary surface, and the active layer (AS) is applied to the dispersion layer (DS).
Claim 7
Dependent Claim
27 words
An optical power limiting device according to claim 5, wherein the thickness of the dispersion layer (DS) is in the range of from 1,000 to 2,000 nm.
Claim 8
Dependent Claim
20 words
An optical power limiting device according to claim 1, wherein the active layer (AS) is made from a cermet material.
Claim 9
Dependent Claim
20 words
An optical power limiting device according to claim 2, wherein the active layer (AS) is made from a cermet material.
Claim 10
Dependent Claim
23 words
An optical power limiting device according to claim 7, wherein said cermet material is one of :Cu in KBr and Cu in Ge.
Claim 11
Dependent Claim
23 words
An optical power limiting device according to claim 8, wherein said cermet material is one of :Cu in KBr and Cu in Ge.
Claim 12
Dependent Claim
20 words
An optical power limiting device according to claim 1, wherein the active layer is made from a highly doped semiconductor.
Claim 13
Dependent Claim
20 words
An optical power limiting device according to claim 2, wherein the active layer is made from a highly doped semiconductor.
Claim 14
Dependent Claim
24 words
An optical power limiting device according to claim 11, wherein said semiconductor is one of Si, Ge, In 2 O 3 :SnO 2 .
Claim 15
Dependent Claim
30 words
An optical power limiting device according to claim 1, wherein the material for the dispersion layer (DS) is one of: a liquid crystal and a substance with a semiconductor-metal transition.
Claim 16
Dependent Claim
30 words
An optical power limiting device according to claim 2, wherein the material for the dispersion layer (DS) is one of: a liquid crystal and a substance with a semiconductor-metal transition.
Claim 17
Dependent Claim
20 words
An optical power limiting device according to claim 14, wherein said substance with a semiconductor-metal transition is VO 2 .
Claim 18
Dependent Claim
55 words
An optical power limiting device according to claim 1, wherein the material for the prism (P) is KBr; the material for the active layer (AS) is Al 2 O 3 , having a thickness of 0.6 μm; and the material for the dispersion layer (DS) is VO 2 , having a thickness of 60 nm.
Claim 19
Dependent Claim
55 words
An optical power limiting device according to claim 2, wherein the material for the prism (P) is KBr; the material for the active layer (AS) is Al 2 O 3 , having a thickness of 0.6 μm; and the material for the dispersion layer (DS) is VO 2 , having a thickness of 60 nm.
Claim 20
Dependent Claim
27 words
An optical power limiting device according to claim 1, wherein the prism (P) is made of a material whose absorption capacity increases substantially as the temperature rises.
Claim 21
Dependent Claim
27 words
An optical power limiting device according to claim 3, wherein the prism (P) is made of a material whose absorption capacity increases substantially as the temperature rises.
Claim 22
Dependent Claim
27 words
An optical power limiting device according to claim 5, wherein the prism (P) is made of a material whose absorption capacity increases substantially as the temperature rises.
Claim 23
Dependent Claim
27 words
An optical power limiting device according to claim 7, wherein the prism (P) is made of a material whose absorption capacity increases substantially as the temperature rises.
Claim 24
Dependent Claim
27 words
An optical power limiting device according to claim 11, wherein the prism (P) is made of a material whose absorption capacity increases substantially as the temperature rises.
Claim 25
Dependent Claim
27 words
An optical power limiting device according to claim 14, wherein the prism (P) is made of a material whose absorption capacity increases substantially as the temperature rises.
Claim 26
Dependent Claim
102 words
Method of protecting an IR detector from high intensity radiation, comprising the steps of: providing a prism having at least one plane boundary surface with two layers applied thereto, a first of said layers being an active layer made of a material having a dielectric function with a real component that is negative in a predetermined wave length range, and the second of said layers being a dispersion layer made of a material having a refraction index in the predetermined wave length range that is strongly dependent on temperature; and heating said dispersion layer in response to increasing intensity of said radiation.
Claim 27
Dependent Claim
102 words
Method of protecting an IR detector from high intensity radiation, comprising the steps of: providing a prism having at least one plane boundary surface with two layers applied thereto, a first of said layers being an active layer made of a material having a dielectric function with a real component that is negative in a predetermined wave length range, and the second of said layers being a dispersion layer made of a material having a refraction index in the predetermined wave length range that is strongly dependent on temperature; and heating said dispersion layer in response to increasing intensity of said radiation.
Claim 28
Dependent Claim
35 words
Method according to claim 25 wherein said heating step comprises interposing said prism in an optical input path of said IR detector, whereby said radiation is conducted into and reflected by the plane boundary surface.
Claim 29
Dependent Claim
120 words
An optical power limiting device whose transmissibility within a predetermined wave length range is a function of intensity of incident radiation, comprising: a prism having at least one plane boundary surface; two layers applied to the plane boundary surface, one above the other, a first of said two layers being an active layer comprising a material having a dielectric function with a real component that is negative in the predetermined wave length range, and the second of said two layers being a dispersion layer comprising a material having a refraction index in the predetermined wave length range that is strongly dependent on temperature; and means for heating said dispersion layer in response to the increasing intensity of said incident radiation.
Claim 30
Dependent Claim
120 words
An optical power limiting device whose transmissibility within a predetermined wave length range is a function of intensity of incident radiation, comprising: a prism having at least one plane boundary surface; two layers applied to the plane boundary surface, one above the other, a first of said two layers being an active layer comprising a material having a dielectric function with a real component that is negative in the predetermined wave length range, and the second of said two layers being a dispersion layer comprising a material having a refraction index in the predetermined wave length range that is strongly dependent on temperature; and means for heating said dispersion layer in response to the increasing intensity of said incident radiation.
Claim 31
Dependent Claim
28 words
Optical power limiting device according to claim 27 wherein said means for heating comprises: means for guiding incident radiation into the prism and onto the plane boundary surface.
Claim 32
Dependent Claim
81 words
An optical power limiting device comprising: a prism having at least one plane boundary surface; said first and second layers applied to the plane boundary surface, one above the other; first layer comprising a material having a dielectric function with a real component that is negative in the predetermined wave length range; said second layer having a variable refraction index; and means for varying said refraction index of said second layer in response to intensity of radiation transmitted to said prism.
Claim 33
Dependent Claim
81 words
An optical power limiting device comprising: a prism having at least one plane boundary surface; said first and second layers applied to the plane boundary surface, one above the other; first layer comprising a material having a dielectric function with a real component that is negative in the predetermined wave length range; said second layer having a variable refraction index; and means for varying said refraction index of said second layer in response to intensity of radiation transmitted to said prism.
Claim 34
Dependent Claim
73 words
Optical power limiting device according to claim 29 wherein said second layer is comprised of a material having a refraction index in a predetermined wave length range that is strongly dependent on temperature; and wherein said means for varying said refraction index comprises means for directing said incident radiation into the prism and onto the plane boundary surface, whereby said second layer is heated in response to increasing intensity of said incident radiation.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-09-12 | 1998-03-14 | 1998-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-12 | 2002-03-14 | 2002-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-09-12 | 2006-03-14 | 2006-09-13 | $7700.00 | Window Closed / Lapsed |