US3821577A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High pressure mercury chromium iodide discharge lamp with phosphor coating
Assignee: Philips North America LLC
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Filing: 1973-04-02
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Granted: 1974-06-28
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Expires: 1993-04-02
Abstract
Abstract A high-efficiency high-intensity blue-emitting discharge lamp combination in which, to the normal arc tube containing a predetermined amount of mercury and the normal outer envelope, there is added a phosphor coating of strontium chloro-apatite activated by divalent europium onto the interior surface of the outer envelope and there is also added chromium and iodine as discharge sustaining additives in the arc tubes. This combination provides a substantially more efficient high-intensity source of blue light than previous sources and is especially useful in the medical and photocopying fields.
Inventors
- 👤 D Larson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 08:26
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/38; H01J61/42; H01J61/44; H01J61/12; H01J61/18
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
66 words
The combination of claim 1, wherein said chromium is present in the amount of about 0.17 milligrams per cubic centimeter of arc tube volume, said mercury is present in the amount of about 2.5 milligrams per cubic centimeter of arc tube volume, and said iodine is present in the amount of about 100 percent of the stoichiometric amount to form CrI2 with said amount of chromium.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |