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US5619098A
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Phosphor and fluorescent display device
Assignee: Futaba Corp
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Filing: 1995-09-15
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Granted: 1997-04-08
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Expires: 2015-09-15
Abstract
Abstract A phosphor is disclosed which is suitable for use for a fluorescent display device and driven at a driving voltage as low as 1 kV or less and free of S and Cd. Compounds of Ti, alkaline earth metal and an element of Group 13 of the periodic table in predetermined amounts are heated at 1100° to 1400° C. for calcination, resulting in a solid solution of the rare earth element and one element of Group 13 being formed in a phosphor matrix made of an oxide of alkaline earth metal and Ti. An example of the phosphor is SrTiO 3 :Pr,Al exhibiting a red luminous color.
Inventors
- 👤 Hitoshi Toki
- 👤 Shigeo Itoh
- 👤 Fumiaki Kataoka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:30
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7701; C09K11/7703; C09K11/7715; C09K11/7716; C09K11/7718; C09K11/7728; C09K11/7729; C09K11/7731; C09K11/7743; C09K11/7744; C09K11/7746
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
38 words
A phosphor comprising: a phosphor matrix made of an oxide of alkaline earth metal and Ti; and a rare earth element and an element of Group 13 of the periodic table which are added to the phosphor matrix.
Claim 2
Dependent Claim
38 words
A phosphor comprising: a phosphor matrix made of an oxide of alkaline earth metal and Ti; and a rare earth element and an element of Group 13 of the periodic table which are added to the phosphor matrix.
Claim 3
Dependent Claim
25 words
A phosphor as defined in claim 1, wherein said alkaline earth metal is one selected from the group consisting of Mg, Sr, Ca and Ba.
Claim 4
Dependent Claim
27 words
A phosphor as defined in claim 1, wherein said rare earth element is one selected from the group consisting of Ce, Eu, Tb, Er, Tm and Pr.
Claim 5
Dependent Claim
25 words
A phosphor as defined in claim 1 or 3, wherein said rare earth element is added in an amount of 0.05 to 5 mol %.
Claim 6
Dependent Claim
26 words
A phosphor as defined in claim 1, wherein said element of Group 13 is one selected from the group consisting of Al, Ca, In and Tl.
Claim 7
Dependent Claim
26 words
A phosphor as defined in claim 1 or 5, wherein said element of Group 13 is added in an amount of 0.05 to 80 mol %.
Claim 8
Dependent Claim
82 words
A fluorescent display device comprising: a vacuum envelope; and an electron source and a phosphor layer which are arranged in said vacuum envelope; said phosphor layer being made of a phosphor and emitting light upon impingement of electrons emitted from said electron source thereon; said phosphor including a phosphor matrix made of an oxide of alkaline earth metal and Ti, and a rare earth element and an element of Group 13 of the periodic table which are added to said phosphor matrix.
Claim 9
Dependent Claim
82 words
A fluorescent display device comprising: a vacuum envelope; and an electron source and a phosphor layer which are arranged in said vacuum envelope; said phosphor layer being made of a phosphor and emitting light upon impingement of electrons emitted from said electron source thereon; said phosphor including a phosphor matrix made of an oxide of alkaline earth metal and Ti, and a rare earth element and an element of Group 13 of the periodic table which are added to said phosphor matrix.
Claim 10
Dependent Claim
65 words
A fluorescent display device as defined in claim 7, wherein said alkaline earth metal is one selected from the group consisting of Mg, Sr, Ca and Ba; said rare earth element is one selected from the group consisting of Ce, Eu, Tb, Er, Tm, and Pr; and said element of Group 13 is one selected from the group consisting of Al, Ga, In and Tl.
Claim 11
Dependent Claim
42 words
A fluorescent display device as defined in claim 7, wherein said rare earth element is added in an amount of 0.05 to 5 mol %; and said element of Group 13 is added in an amount of 0.05 to 80 mol %.
Claim 12
Dependent Claim
16 words
A fluorescent display device as defined in claim 7, said electron source comprises a filamentary cathode.
Claim 13
Dependent Claim
19 words
A fluorescent display device as defined in claim 7, wherein said electron source comprises a field emission cathode (FEC).
References Cited (Backward Citations)
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| 7.5 Years (Year 8) | 2004-04-07 | 2004-10-07 | 2005-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-04-07 | 2008-10-07 | 2009-04-08 | $7700.00 | Window Closed / Lapsed |