US3813569A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Luminescent screen and mercury vapor discharge lamp containing same
Assignee: US Philips Corp
•
Filing: 1972-12-08
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Granted: 1974-05-28
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Expires: 1992-12-08
Abstract
Abstract A luminescent silicate activated by bivalent europium defined by the formula Sr1-x-y-z-pBazCayMgzEupB2Si2O8 in which O </= x </= 0.
Inventors
- 👤 J Verstegen
- 👤 Meester E De
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:32
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7728; C09K11/774; C09K11/77342
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
20 words
A luminescent screen as claimed in claim 1, characterized in that 0.10 < or = x < or = 0.40.
Claim 2
Dependent Claim
20 words
A luminescent screen as claimed in claim 2, characterized in that 0.05 < or = z < or = 0.15.
Claim 3
Dependent Claim
20 words
A luminescent screen as claimed in claim 3, characterized in that 0.03 < or = p < or = 0.10.
Claim 4
Dependent Claim
16 words
A low-pressure mercury vapour discharge lamp provided with a luminescent screen as claimed in claim 1.
Claim 5
Dependent Claim
16 words
A high-pressure mercury vapour discharge lamp provided with a luminescent screen as claimed in claim 1.
Claim 6
Dependent Claim
65 words
A luminescent silicate activated by bivalent europium defined by the formula Sr1 x y z pBaxCayMgzEupB2Si2O8, in which 0 < or = x < or = 0.60 0 < or = y < or = 0.50 0 < or = z < or = 0.25 0.01 < or = p < or = 0.20 x + y + z * p < or = 0.70
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-27 | 1977-11-26 | 1978-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-27 | 1981-11-26 | 1982-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-27 | 1985-11-26 | 1986-05-28 | $7700.00 | Window Closed / Lapsed |