US4987342A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-ballasted glow discharge lamp having indirectly-heated cathode
Assignee: Osram Sylvania Inc
•
Filing: 1989-03-27
•
Granted: 1991-01-22
•
Expires: 2009-03-27
Abstract
Abstract A negative glow discharge lamp including an anode and an indirectly-heated cathode disposed within a phosphor-coated envelope. The cathode includes a heater filament surrounded by a metallic cylinder which is coated with an emissive material. The differential resistance of the heater filament is sufficient to internally ballast the flow discharge lamp.
Inventors
- 👤 Valery Godyak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:40
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/64; H01J61/02; H01J61/56
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
107 words
A self-ballasted negative glow discharge lamp comprising: a light-transmitting envelope containing a gas fill material; a phosphor coating disposed on the inner surface of said envelope; an anode located within said envelope; an indirectly-heated cathode located within said envelope for emitting electrons, said indirectly-heated cathode including a heater filament surrounded by a metallic cylinder coated with an emissive material, said heater filament connected in series with the discharge so that discharge current flows therethrough, said heater filament having a resistance sufficient by itself to ballast said negative glow discharge lamp; and lead-in wires coupled to said cathode and anode extending through and hermetically sealed in said envelope.
Claim 2
Dependent Claim
107 words
A self-ballasted negative glow discharge lamp comprising: a light-transmitting envelope containing a gas fill material; a phosphor coating disposed on the inner surface of said envelope; an anode located within said envelope; an indirectly-heated cathode located within said envelope for emitting electrons, said indirectly-heated cathode including a heater filament surrounded by a metallic cylinder coated with an emissive material, said heater filament connected in series with the discharge so that discharge current flows therethrough, said heater filament having a resistance sufficient by itself to ballast said negative glow discharge lamp; and lead-in wires coupled to said cathode and anode extending through and hermetically sealed in said envelope.
Claim 3
Dependent Claim
27 words
The negative glow discharge lamp as set forth in claim 1 wherein said anode is in the form of a cylindrical wire cage surrounding said indirectly-heated cathode.
Claim 4
Dependent Claim
23 words
The negative glow discharge lamp as set forth in claim 1 wherein said fill material includes neon at a pressure of 2 torr.
Claim 5
Dependent Claim
148 words
A negative glow discharge lamp system comprising: a glow discharge lap including a light-transmitting envelope containing a gas fill material, a phosphor coating disposed on the inner surface of said envelope, an anode located within said envelope, an indirectly-heated cathode located within said envelope for emitting electrons, said indirectly-heated cathode including a heater filament surrounded by a metallic cylinder coated with an emissive material, said heater filament connected in series with the discharge so that discharge current flows therethrough, said heater filament having a resistance sufficient by itself to ballast said negative glow discharge lamp, and lead-in wires coupled to said cathode and anode extending through and hermetically sealed in said envelope; a dc power source having a positive and negative terminal, said positive terminal connected to said anode and said negative terminal connected to one end of said heater filament; and a starter means shunting said lamp.
Claim 6
Dependent Claim
148 words
A negative glow discharge lamp system comprising: a glow discharge lap including a light-transmitting envelope containing a gas fill material, a phosphor coating disposed on the inner surface of said envelope, an anode located within said envelope, an indirectly-heated cathode located within said envelope for emitting electrons, said indirectly-heated cathode including a heater filament surrounded by a metallic cylinder coated with an emissive material, said heater filament connected in series with the discharge so that discharge current flows therethrough, said heater filament having a resistance sufficient by itself to ballast said negative glow discharge lamp, and lead-in wires coupled to said cathode and anode extending through and hermetically sealed in said envelope; a dc power source having a positive and negative terminal, said positive terminal connected to said anode and said negative terminal connected to one end of said heater filament; and a starter means shunting said lamp.
Claim 7
Dependent Claim
19 words
The glow discharge lamp system as set forth claim 4 wherein said starter means is a glow discharge starter.
References Cited (Backward Citations)
US2108537A
Cited
US2020736A
Cited
US2024529A
Cited
US2135714A
Cited
US2099111A
Cited
US2200951A
Cited
US2295043A
Cited
US2495580A
Cited
US2507696A
Cited
US3243632A
Cited
US3349282A
Cited
US3836816A
Cited
US3968396A
Cited
US4316124A
Cited
US4268780A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-01-21 | 1994-07-23 | 1995-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-01-21 | 1998-07-23 | 1999-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-01-21 | 2002-07-23 | 2003-01-22 | $7700.00 | Window Closed / Lapsed |