US4052634A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High-pressure gas discharge lamp and electron emissive electrode structure therefor
Assignee: US Philips Corp
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Filing: 1976-06-17
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Granted: 1977-10-04
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Expires: 1996-06-17
Abstract
Abstract A high-pressure gas discharge lamp having an electrode consisting of a support of a high-melting metal provided with an electron emissive material. The emissive material consists mainly of one or more oxidic compounds containing (a) at least one of the rare earth metal oxides, (b) alkaline earth metal oxide in a quantity of 0.66 to 4 mole per mole of rare earth oxide and (c) at least one of the oxides of tungsten and molybdenum in a quantity of 0.25 to 0.40 mole per mole of alkaline earth metal oxide, the alkaline earth metal oxide consisting of at least 25 mol.% of barium oxide.
Inventors
- 👤 Johannis De Kok
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:46
CPC Classifications
H; H01; H01J; H01J61/00; H01J61/02; H01J61/04; H01J61/06; H01J61/073
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
142 words
A high-pressure gas discharge lamp having a radiation transmissive envelope containing electrodes and an ionizable medium in which the discharge is maintained, at least one of the electrodes consisting of a support of a high-melting metal provided with an electron emissive material which contains an alkaline earth metal and at least one of the metals tungsten and molybdenum, characterized in that the electron emissive material mainly consists of at least one oxidic compound containing at least one of the rare earth metal oxides, alkaline earth metal oxide in a quantity of 0.66 to 4 mole per mole of rare earth metal oxide and at least one of the oxides of tungsten and molybdenum in a quantity of 0.25 to 0.40 mole per mole of alkaline earth metal oxide, the alkaline earth metal oxide consisting of at least 25 mol.% of barium oxide.
Claim 2
Dependent Claim
142 words
A high-pressure gas discharge lamp having a radiation transmissive envelope containing electrodes and an ionizable medium in which the discharge is maintained, at least one of the electrodes consisting of a support of a high-melting metal provided with an electron emissive material which contains an alkaline earth metal and at least one of the metals tungsten and molybdenum, characterized in that the electron emissive material mainly consists of at least one oxidic compound containing at least one of the rare earth metal oxides, alkaline earth metal oxide in a quantity of 0.66 to 4 mole per mole of rare earth metal oxide and at least one of the oxides of tungsten and molybdenum in a quantity of 0.25 to 0.40 mole per mole of alkaline earth metal oxide, the alkaline earth metal oxide consisting of at least 25 mol.% of barium oxide.
Claim 3
Dependent Claim
48 words
A high-pressure gas discharge lamp as claimed in claim 1, characterized in that said emissive material contains at least one of the oxides of yttrium, cerium and lanthanum and alkaline earth metal oxide in a quantity of 1.5 to 3 mole per mole of rare earth metal oxide.
Claim 4
Dependent Claim
20 words
A high-pressure discharge lamp as claimed in claim 1 in which said ionizable medium contains mercury and a rare gas.
Claim 5
Dependent Claim
21 words
A high-pressure discharge lamp as claimed in claim 1 in which said ionizable medium contains sodium, mercury and a rare gas.
Claim 6
Dependent Claim
46 words
A high-pressure gas discharge lamp as claimed in claim 2, characterized in that said emissive material contains yttrium oxide and barium oxide and a material selected from the group consisting of strontium oxide and calcium oxide in a quantity equimolar to the quantity of barium oxide.
Claim 7
Independent Claim
108 words
A method for producing a gas discharge lamp which comprises: providing a tungsten electrode support; providing a suspension on said support which contains 20 to 60 mol.% of at least one of the rare earth metal oxides, 40 to 80 mol.% of alkaline earth metal carbonate, in which at least 25 mol.% of the carbonate is barium carbonate and 0 to 10 mol.% of tungsten; subjecting said support and suspension to a heat treatment at a temperature of 1500° to 2100° C in an inert or reducing atmosphere; and then positioning said electrode support within a lamp envelope; and then providing an ionizable medium within said lamp envelope.
Claim 8
Independent Claim
108 words
A method for producing a gas discharge lamp which comprises: providing a tungsten electrode support; providing a suspension on said support which contains 20 to 60 mol.% of at least one of the rare earth metal oxides, 40 to 80 mol.% of alkaline earth metal carbonate, in which at least 25 mol.% of the carbonate is barium carbonate and 0 to 10 mol.% of tungsten; subjecting said support and suspension to a heat treatment at a temperature of 1500° to 2100° C in an inert or reducing atmosphere; and then positioning said electrode support within a lamp envelope; and then providing an ionizable medium within said lamp envelope.
Claim 9
Independent Claim
106 words
A method for producing a gas discharge lamp which comprises: providing a tungsten electrode support; providing a suspension on said support which contains 20 to 60 mol.% of at least one of the rare earth metal oxides, 40 to 80 mol.% of alkaline earth metal carbonate, in which at least 25 mol.% of the carbonate is barium carbonate and 0 to 10 mol.% of tungsten; positioning said electrode support within a lamp envelope; subjecting said support and suspension to a heat treatment at a temperature of 1500° to 2100° C in an inert or reducing atmosphere; and then providing an ionizable medium within said lamp envelope.
Claim 10
Independent Claim
106 words
A method for producing a gas discharge lamp which comprises: providing a tungsten electrode support; providing a suspension on said support which contains 20 to 60 mol.% of at least one of the rare earth metal oxides, 40 to 80 mol.% of alkaline earth metal carbonate, in which at least 25 mol.% of the carbonate is barium carbonate and 0 to 10 mol.% of tungsten; positioning said electrode support within a lamp envelope; subjecting said support and suspension to a heat treatment at a temperature of 1500° to 2100° C in an inert or reducing atmosphere; and then providing an ionizable medium within said lamp envelope.
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) | 1980-10-03 | 1981-04-04 | 1981-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-03 | 1985-04-04 | 1985-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-03 | 1989-04-04 | 1989-10-04 | $7700.00 | Window Closed / Lapsed |