US5455489A
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Displays comprising doped nanocrystal phosphors
Assignee: Nanocrystals Technology LP
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Filing: 1994-04-11
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Granted: 1995-10-03
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Expires: 2014-04-11
Abstract
Abstract Electronic displays including CRTs and projection TV (PTV), field emission displays (FED), plasma and electroluminescent (EL) displays, all of whom involve the use of luminescent materials (active displays) for the transfer of information to an audience. The phosphor material used in these displays comprises doped nanocrystals; tiny, separated particles of the order of 100 angstroms or less and thus exhibiting quantum-confined properties. These quantum-confined particles of certain luminescent materials when doped with an activator yield ultra-fast and efficient phosphors. The resultant displays will possess high brightness and high resolution. In addition, certain of the displays will exhibit digital control and increased gray scale.
Inventors
- 👤 Rameshwar N. Bhargava
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:10
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7701; C09K11/7702; H; H01; H01J; H01J29/00; H01J29/02; H01J29/10; H01J29/18; H01J29/20; H05; H05B; H05B33/00; H05B33/12; H05B33/14
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
73 words
A display device comprising: (a) a phosphor material capable upon excitation of emitting radiation in the UV and visible spectral range, (b) means for exciting the phosphor material, (c) said phosphor material comprising separated particles of a host compound activated by a dopant providing when excited radiative transitions emitting in said UV and visible spectral range, said particles being of the order of 100 angstroms or less in size and exhibiting quantum-confined properties.
Claim 2
Dependent Claim
73 words
A display device comprising: (a) a phosphor material capable upon excitation of emitting radiation in the UV and visible spectral range, (b) means for exciting the phosphor material, (c) said phosphor material comprising separated particles of a host compound activated by a dopant providing when excited radiative transitions emitting in said UV and visible spectral range, said particles being of the order of 100 angstroms or less in size and exhibiting quantum-confined properties.
Claim 3
Dependent Claim
14 words
The display device of claim 1, wherein the host compound is a II-VI compound.
Claim 4
Dependent Claim
14 words
The display device of claim 2, wherein the dopant is a rare earth element.
Claim 5
Dependent Claim
21 words
The display device of claim 3, wherein the rare-earth element is selected from the group consisting of Tm, Tb, and Eu.
Claim 6
Dependent Claim
19 words
The display device of claim 1, wherein the host compound is a line-emitting phosphor with a rare earth dopant.
Claim 7
Dependent Claim
15 words
The display device of claim 1, wherein the particle size is between about 2-5 nm.
Claim 8
Dependent Claim
22 words
The display device of claim 1, wherein the phosphor material is in the form of a layer of 1000 Å or less.
Claim 9
Dependent Claim
21 words
The display device of claim 2, wherein the device is a CRT, and the means for exciting is an electron beam.
Claim 10
Dependent Claim
25 words
The display device of claim 8, wherein the means for exciting comprises means for accelerating the electron beam with a low voltage under 10 kilovolts.
Claim 11
Dependent Claim
28 words
The display device of claim 9, wherein the means for exciting comprises means for accelerating the electron beam with a low voltage in the range of 10-500 volts.
Claim 12
Dependent Claim
21 words
The display device of claim 2, wherein the device is an X-Y matrix-addressed device, and the means for exciting is electrons.
Claim 13
Dependent Claim
20 words
The display device of claim 11, wherein the device comprises an active structure comprising sharp microtips for generating cold electrons.
Claim 14
Dependent Claim
14 words
The display device of claim 11, further comprising pulse-width-modulation means for driving the device.
Claim 15
Dependent Claim
15 words
The display device of claim 11, further comprising means for digital addressing of the device.
Claim 16
Dependent Claim
32 words
The display device of claim 2, wherein the device is a beam index tube, the means for exciting is an electron beam, and the phosphor is in the form of fine lines.
Claim 17
Dependent Claim
22 words
The display device of claim 2, wherein the device is an X-Y matrix-addressed device, and the means for exciting is UV radiation.
Claim 18
Dependent Claim
28 words
The display device of claim 2, wherein the device is an X-Y matrix-addressed device, and the means for exciting comprises means for causing electrical breakdown in the device.
Claim 19
Dependent Claim
17 words
The display device of claim 17, wherein the device is a thin film device comprising dielectric layers.
Claim 20
Dependent Claim
27 words
The display device of claim 16, wherein the device comprises a space filled with a gas mixture to facilitate local gas discharges which generate the UV radiation.
References Cited (Backward Citations)
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