US5788883A
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Determination process for determining if quantum splitting phosphors are obtained and novel compositions
Assignee: General Electric Co
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Filing: 1997-02-28
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Granted: 1998-08-04
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Expires: 2017-02-28
Abstract
Abstract Quantum splitting phosphors with host lattices activated by praseodymium +3 where covalency of the Pr +3 -ligand bond is maintained so that the center of gravity of the Pr +3 4f5d band level is located above the 1 S 0 level and the host lattice has a band gap of greater than about 5 eV.
Inventors
- 👤 Alok Mani Srivastava
- 👤 William Winder Beers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:35
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7766; C09K11/7772; C09K11/7773; C09K11/7706; C09K11/7712; C09K11/7767; C09K11/7769; C09K11/777; C09K11/778
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
233 words
A determination process for determining if quantum splitting phosphors are obtained where a host lattice is activated by Pr +3 , the process comprising the steps of: determining if the Pr +3 is incorporated in the host having an effective coordination number for the Pr +3 ion so that the Pr +3 energy position of its 4f5d band is located above a 1 S 0 state; determining if the Pr +3 4f5d band and the 1 S 0 state are positioned below the host lattice conduction band where Pr +3 is incorporated in a lattice having a band gap greater than about 5 electron volts; and determining if a site symmetry of the host lattice for the Pr +3 has been chosen having an effective crystal field strength and an effective Pr +3 to host lattice bond distance; wherein if the Pr +3 is incorporated in the host having an effective coordination number for the Pr +3 ion so that the Pr +3 energy position of its 4f5d band is located above a 1 S 0 state, the Pr +3 4f5d band and the 1 S 0 state are positioned below the host lattice conduction band, and the site symmetry of the host lattice for the Pr +3 has been chosen having an effective crystal field strength and an effective Pr +3 to host lattice bond distance a quantum splitting phosphor is obtained.
Claim 2
Dependent Claim
233 words
A determination process for determining if quantum splitting phosphors are obtained where a host lattice is activated by Pr +3 , the process comprising the steps of: determining if the Pr +3 is incorporated in the host having an effective coordination number for the Pr +3 ion so that the Pr +3 energy position of its 4f5d band is located above a 1 S 0 state; determining if the Pr +3 4f5d band and the 1 S 0 state are positioned below the host lattice conduction band where Pr +3 is incorporated in a lattice having a band gap greater than about 5 electron volts; and determining if a site symmetry of the host lattice for the Pr +3 has been chosen having an effective crystal field strength and an effective Pr +3 to host lattice bond distance; wherein if the Pr +3 is incorporated in the host having an effective coordination number for the Pr +3 ion so that the Pr +3 energy position of its 4f5d band is located above a 1 S 0 state, the Pr +3 4f5d band and the 1 S 0 state are positioned below the host lattice conduction band, and the site symmetry of the host lattice for the Pr +3 has been chosen having an effective crystal field strength and an effective Pr +3 to host lattice bond distance a quantum splitting phosphor is obtained.
Claim 3
Dependent Claim
25 words
A process according to claim 1 where the host lattice is an oxide host lattice or a halide host lattice or a oxyhalide host lattice.
Claim 4
Dependent Claim
25 words
A process according to claim 2 where the oxide host lattice has an average Pr +3 to oxygen bond distance greater than about 2.561 Å.
Claim 5
Dependent Claim
49 words
A process according to claim 3 where the oxide host lattice having the average Pr +3 to oxygen bond distance greater than about 2.561Å is selected from the group consisting of SrAl 12 O 19 , LaMgB 5 O 10 , LaB 3 O 6 , and mixtures thereof.
Claim 6
Dependent Claim
25 words
A process according to claim 2 where the halide host lattice has an average Pr +3 to halide bond distance greater than about 2.28 Å.
Claim 7
Dependent Claim
30 words
A process according to claim 1 where the site symmetry of the host lattice for the Pr +3 is chosen so maximum quantum efficiency may be generated by the phosphor.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 2001-08-03 | 2002-02-02 | 2002-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-08-03 | 2006-02-02 | 2006-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-08-03 | 2010-02-02 | 2010-08-04 | $7700.00 | Window Closed / Lapsed |