US4812659A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Infrared sensing device outputting blue-green light
Assignee: GIMMEL GERALD K PERSONAL REPRESENTATIVE OF ESTATE OF JOSEPH LINDMAYER
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Filing: 1987-04-03
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Granted: 1989-03-14
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Expires: 2007-04-03
Abstract
Abstract Photoluminescent materials useful for detection of infrared light are prepared using a base material, first and second dopants, barium sulfate and a fusable salt. The base material is an alkaline earth metal sulfide or selenide such as strontium sulfide. Barium sulfate is used to increase the brightness of output light, whereas lithium fluoride is used to allow the material to be fused together. Samarium and cerium oxide are used as the first and second dopants for providing electron traps. The photoluminescent material is made according to a process involving heating of the material to a fusing temperature, grinding the material after cooling, and reheating the material to below the fusing temperature, but sufficiently high to repair the crystal surfaces. An infrared sensing device or card may be constructed by placing the material in a transparent binder and applying it to a substrate. The material and its substrate may then by encapsulated.
Inventors
- 👤 Joseph Lindmayer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 01:35
CPC Classifications
G; G11; G11C; G11C13/00; G11C13/04; G01; G01T; G01T1/00; G01T1/02; G01T1/10; G01T1/11; G01T1/16; G01T1/20; G01T1/2012
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
66 words
An infrared sensing device comprising: a substrate, and a photoluminescent material disposed on said substrate, said photoluminescent material comprising: a base material comprising substantially strontium sulfide, a first dopant of samarium provided in a quantity of between 70 to 300 parts per million by weight, and a second dopant of cerium oxide provided in a quantity of between 600 to 1500 parts per million by weight.
Claim 2
Dependent Claim
66 words
An infrared sensing device comprising: a substrate, and a photoluminescent material disposed on said substrate, said photoluminescent material comprising: a base material comprising substantially strontium sulfide, a first dopant of samarium provided in a quantity of between 70 to 300 parts per million by weight, and a second dopant of cerium oxide provided in a quantity of between 600 to 1500 parts per million by weight.
Claim 3
Dependent Claim
14 words
An infrared sensing device as described in claim 1, wherein the substrate is transparent.
Claim 4
Dependent Claim
14 words
An infrared sensing device as described in claim 1, wherein the substrate is opaque.
Claim 5
Dependent Claim
24 words
An infrared sensing device as described in claim 3, wherein the opaque substrate has a reflective surface on which the photoluminescent material is disposed.
Claim 6
Dependent Claim
25 words
An infrared sensing device as described in claim 3, wherein the opaque substrate has a light colored surface on which the photoluminescent material is disposed.
Claim 7
Dependent Claim
14 words
An infrared sensing device as described in claim 1, wherein the substrate is rigid.
Claim 8
Dependent Claim
14 words
An infrared sensing device as described in claim 1, wherein the substrate is flexible.
Claim 9
Dependent Claim
14 words
An infrared sensing device as described in claim 1, wherein the substrate is paper.
Claim 10
Dependent Claim
14 words
An infrared sensing device as described in claim 1, wherein the substrate is plastic.
Claim 11
Dependent Claim
19 words
An infrared sensing device as described in claim 1, wherein the photoluminescent material has a thickness of 1-500 microns.
Claim 12
Dependent Claim
21 words
An infrared sensing device as described in claim 1, wherein the substrate and photoluminescent material are encapsulated with a transparent material.
Claim 13
Dependent Claim
17 words
An infrared sensing device as described in claim 1, wherein the photoluminescent material is in crystalline form.
Claim 14
Dependent Claim
22 words
An infrared sensing device as described in claim 1, wherein the photoluminescent material is in powder form mixed with a transparent binder.
Claim 15
Dependent Claim
18 words
An infrared sensing device as described in claim 1, wherein the photoluminescent material is in micro crystalline form.
Claim 16
Dependent Claim
17 words
An infrared sensing device as described in claim 1, wherein the photoluminescent material further comprises barium sulfate.
Claim 17
Dependent Claim
18 words
An infrared sensing device as described in claim 1, wherein the photoluminescent material further comprises a fusable salt.
Claim 18
Dependent Claim
16 words
An infrared sensing device as described in claim 16, wherein said fusable salt comprises lithium fluoride.
Claim 19
Dependent Claim
27 words
An infrared sensing device as described in claim 1, wherein the base material is strontium sulfide, and the photoluminescent material additionally comprises barium sulfate and lithium fluoride.
Claim 20
Dependent Claim
34 words
An infrared sensing device as described in claim 1, wherein the photoluminescent material is disposed as a thin film on the substrate in a micro crystalline form having a thickness of approximately 0.5 micron.
References Cited (Backward Citations)
US2468452A
Cited
US2468714A
Cited
US2521124A
Cited
US2485903A
Cited
US2979467A
Cited
US3668142A
Cited
US4365184A
Cited
US4211813A
Cited
US4292107A
Cited
US4510174A
Cited
US4517463A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-03-13 | 1992-09-12 | 1993-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-13 | 1996-09-12 | 1997-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-13 | 2000-09-12 | 2001-03-14 | $7700.00 | Window Closed / Lapsed |