US5122671A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Terbium activated silicate luminescent glasses for use in converting x-ray radiation into visible radiation
Assignee: COLLIMATED HOLES Inc
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Filing: 1991-06-24
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Granted: 1992-06-16
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Expires: 2011-06-24
Abstract
Abstract This invention relates to terbium activated silicate luminescent glasses exhibiting reduced afterglow and enhanced luminescence due to incorporation therein of selected rare earth oxides of cerium, europium and godolinium.
Inventors
- 👤 Robert A. Buchanan
- 👤 Clifford Bueno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:33
CPC Classifications
G; G21; G21K; G21K4/00; C; C03; C03C; C03C3/00; C03C3/04; C03C3/062; C03C3/076; C03C3/095; C03C4/00; C03C4/12; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7743; C09K11/77494; C09K11/7766; C09K11/77744; C09K11/7783; C09K11/77924; G21K2004/06
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
186 words
A method of converting x-ray radiation into radiation in the visible spectrum comprising the steps of: a. positioning in said x-ray radiation field a luminescent terbium-activated, silicate glass exhibiting strong visible luminescence, low phosphorescence and low background buildup when exposed to x-ray radiation in the range of 5 KeV to 16 MeV and consisting essentially, by weight on the oxide basis, of about 3-25% R 2 O wherein R 2 O consists of 0-5% Li 2 O, 0-25% Na 2 O, 0-25% K 2 O, 0-25% Rb 2 O, and 0-25% Cs 2 O; 5-55% RO wherein RO consists of 0-20% MgO, 0-30% CaO, 0-45% SrO and 0-55% BaO; 35-70% SiO 2 ; 0-20% R 2 O 3 wherein R 2 O 3 consists of 0-20% La 2 O 3 and 0-15% Y 2 O 3 ; 0.1-2% of at least one oxide selected from the group consisting of cerium oxide and europium oxide; 5-20% Tb 2 O 3 ; and 1-15% Gd 2 O 3 ; and b. irradiating said glass with said x-ray radiation, thereby to convert said x-ray radiation into said visible radiation.
Claim 2
Independent Claim
186 words
A method of converting x-ray radiation into radiation in the visible spectrum comprising the steps of: a. positioning in said x-ray radiation field a luminescent terbium-activated, silicate glass exhibiting strong visible luminescence, low phosphorescence and low background buildup when exposed to x-ray radiation in the range of 5 KeV to 16 MeV and consisting essentially, by weight on the oxide basis, of about 3-25% R 2 O wherein R 2 O consists of 0-5% Li 2 O, 0-25% Na 2 O, 0-25% K 2 O, 0-25% Rb 2 O, and 0-25% Cs 2 O; 5-55% RO wherein RO consists of 0-20% MgO, 0-30% CaO, 0-45% SrO and 0-55% BaO; 35-70% SiO 2 ; 0-20% R 2 O 3 wherein R 2 O 3 consists of 0-20% La 2 O 3 and 0-15% Y 2 O 3 ; 0.1-2% of at least one oxide selected from the group consisting of cerium oxide and europium oxide; 5-20% Tb 2 O 3 ; and 1-15% Gd 2 O 3 ; and b. irradiating said glass with said x-ray radiation, thereby to convert said x-ray radiation into said visible radiation.
Claim 3
Dependent Claim
22 words
A method in accordance with claim 1 wherein said terbium oxide is present in an amount of about 6 to 12 percent.
Claim 4
Dependent Claim
28 words
A method in accordance with claim 1 wherein said at least one oxide of cerium and europium is present in an amount of about 0.1 to 1.0 percent.
Claim 5
Dependent Claim
22 words
A method in accordance with claim 1 wherein said gadolinium oxide is present in an amount of about 1 to 10 percent.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1995-06-16 | 1995-12-16 | 1996-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-16 | 1999-12-16 | 2000-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-16 | 2003-12-16 | 2004-06-16 | $7700.00 | Window Closed / Lapsed |