← Back to Patent Explorer
US4812660A Expired / Lapsed US ⏱️ 0.0 years remaining

Photoluminescent materials for outputting yellow-green light

Assignee: GIMMEL GERALD K PERSONAL REPRESENTATIVE OF ESTATE OF JOSEPH LINDMAYER
•
Filing: 1987-08-14
•
Granted: 1989-03-14
•
Expires: 2007-08-14
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Photoluminescent materials useful for detection of infrared light are prepared using a base material, first and second dopants and a fusible salt. The base material is an alkaline earth metal sulfide such as calcium sulfide. Lithium fluoride is used to enhance the interdiffusion of materials. Samarium and cerium sulfide 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. The material is then placed in a transparent binder and applied to a substrate, or deposited as a thin film directly on a substrate for different uses.

Inventors

  • 👤 Joseph Lindmayer

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 05:18
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: 15
Claim 1
Independent Claim 92 words
An electron trapping photoluminescent infrared stimulable phosphor having a peak infrared sensitivity within the range of 1.12 or 1.22 microns and emitting in response to infrared radiation an output of yellow-green light comprising: a base material comprising substantially calcium sulfide; a first dopant of samarium is provided in a quantity of between 50 and 300 part per million by weight, and a second dopant selected from the group of cerium oxide, cerium flouride, cerium chloride, and cerium sulfide is provided in a quantity between 200 to 1500 part per million by weight.
Claim 2
Dependent Claim 92 words
An electron trapping photoluminescent infrared stimulable phosphor having a peak infrared sensitivity within the range of 1.12 or 1.22 microns and emitting in response to infrared radiation an output of yellow-green light comprising: a base material comprising substantially calcium sulfide; a first dopant of samarium is provided in a quantity of between 50 and 300 part per million by weight, and a second dopant selected from the group of cerium oxide, cerium flouride, cerium chloride, and cerium sulfide is provided in a quantity between 200 to 1500 part per million by weight.
Claim 3
Dependent Claim 11 words
The photoluminescent material of claim 1, further comprising a fusible salt.
Claim 4
Dependent Claim 13 words
The photoluminescent material of claim 2, wherein said fusible salt comprises lithium fluoride.
Claim 5
Dependent Claim 28 words
The photoluminescent material of claim 2, wherein the fusible salt is provided in a quantity of up to 10 parts per 100 parts of total composition by weight.
Claim 6
Dependent Claim 27 words
The photoluminescent material of claim 1, wherein said second dopant comprises cerium sulfide, there being between 200 and 900 parts per million of cerium sulfide by weight.
Claim 7
Dependent Claim 27 words
The photoluminescent material of claim 1, wherein said second dopant comprises cerium sulfide, there being between 400 and 600 parts per million of cerium sulfide by weight.
Claim 8
Dependent Claim 27 words
The photoluminescent material of claim 1, wherein said second dopant comprises cerium oxide, there being between 300 and 1500 parts per million of cerium oxide by weight.
Claim 9
Dependent Claim 43 words
The photoluminescent material of claim 1, wherein the first dopant, samarium, is provided in a quantity of between 50-300 parts per million by weight, and the second dopant, cerium sulfide, is provided in a quantity of between 200-900 parts per million by weight.
Claim 10
Dependent Claim 43 words
The photoluminescent material of claim 1, wherein the first dopant, samarium, is provided in a quantity of between 50-300 parts per million by weight, and the second dopant, cerium oxide, is provided in a quantity of between 300-1500 parts per million by weight.
Claim 11
Dependent Claim 14 words
The photoluminescent material of claim 1, wherein said material is disposed upon a substrate.
Claim 12
Dependent Claim 11 words
The photoluminescent material of claim 10, wherein the substrate is alumina.
Claim 13
Dependent Claim 11 words
The photoluminescent material of claim 10, wherein the substrate is sapphire.
Claim 14
Dependent Claim 18 words
The photoluminescent material of claim 10, wherein the material is from 0.5 micron to 500 microns in thickness.
Claim 15
Dependent Claim 30 words
The photoluminescent material of claim 1, wherein the photoluminescent material is disposed as a thin film on a substrate in a microcrystalline form having a thickness of approximately 0.5 micron.

References Cited (Backward Citations)

GB492735A Cited
US2527365A Cited
US2522074A Cited
US2521124A Cited
US2485903A Cited
US2979467A Cited
US4064066A Cited
US3767588A Cited
US4365184A Cited
US4510174A Cited
WO1985004892A1 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

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag