US3656019A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydrogen-filled gas detector having cathode helix supported by envelope wall
Assignee: Melpar Inc
•
Filing: 1967-08-11
•
Granted: 1972-04-11
•
Expires: 1987-08-11
Abstract
Abstract An ultraviolet detector in which the electrode configuration is non-symmetrical in that one electrode operates permanently as the emitter and the other as the collector, at least one of the electrodes supported by the inner surface of the tube envelope and offering an expansive wide angle field of view for incoming ultraviolet radiation. The electrodes are DC biased to provide a high voltage difference therebetween, i.e., between cathode, or emitter, and anode or collector, the former responsive to each photon of ultraviolet energy incident from within the wide angle.
Inventors
- 👤 Richard W Stowe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:35
CPC Classifications
H; H01; H01J; H01J40/00; H01J40/02; H01J40/04; H01J47/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
311 words
An optical radiation detector tube comprising a hermetically sealed elongated cylindrical envelope transparent to ultraviolet radiation over its entire cylindrical surface, said envelope having a longitudinal axis and being closed by end headers, a pair of spaced electro-polished tungsten electrodes housed by said envelope, each of uniform diameter throughout, one of said electrodes constituting a cathode composed of metal having a work function selected for photo-emission of electrons in response to incidence of only preselected wave lengths of ultraviolet radiation thereon with cut off within the range of about 1,500 A to 2,800 A, the other of said electrodes constituting the anode, both of said electrodes having a common longitudinal axis coincident with the longitudinal axis of said envelope, said cathode beinG a helix having spaced apart turns and contacting throughout its length, the interior surface of said envelope and being wholly supported thereby, at least a portion of the cylindrical surface of said envelope being unobstructed by said electrodes to permit passage of optical radiation incident on the exterior of said tube to the interior of said tube via said unobstructed surface, said anode extending axially only and supported solely by said headers, an ionizable gas in said envelope, and respective leads constituted of extensions of said electrodes made of the same metal as said electrodes and continuous therewith without connections or splices of any kind extending from said envelope for application of a d-c potential difference between said electrodes to provide an electric field for accelerating electrons liberated by said cathode toward said anode, said gas being ionizable in response to emission of electrons from said cathode sufficiently that incidence of individual photons of ultraviolet radiation on said cylindrical surface is effective to produce emission of electrons from said cathode and consequent triggering of ionization avalanche discharge between said electrodes when voltage is applied between said anode and cathode.
Claim 2
Dependent Claim
311 words
An optical radiation detector tube comprising a hermetically sealed elongated cylindrical envelope transparent to ultraviolet radiation over its entire cylindrical surface, said envelope having a longitudinal axis and being closed by end headers, a pair of spaced electro-polished tungsten electrodes housed by said envelope, each of uniform diameter throughout, one of said electrodes constituting a cathode composed of metal having a work function selected for photo-emission of electrons in response to incidence of only preselected wave lengths of ultraviolet radiation thereon with cut off within the range of about 1,500 A to 2,800 A, the other of said electrodes constituting the anode, both of said electrodes having a common longitudinal axis coincident with the longitudinal axis of said envelope, said cathode beinG a helix having spaced apart turns and contacting throughout its length, the interior surface of said envelope and being wholly supported thereby, at least a portion of the cylindrical surface of said envelope being unobstructed by said electrodes to permit passage of optical radiation incident on the exterior of said tube to the interior of said tube via said unobstructed surface, said anode extending axially only and supported solely by said headers, an ionizable gas in said envelope, and respective leads constituted of extensions of said electrodes made of the same metal as said electrodes and continuous therewith without connections or splices of any kind extending from said envelope for application of a d-c potential difference between said electrodes to provide an electric field for accelerating electrons liberated by said cathode toward said anode, said gas being ionizable in response to emission of electrons from said cathode sufficiently that incidence of individual photons of ultraviolet radiation on said cylindrical surface is effective to produce emission of electrons from said cathode and consequent triggering of ionization avalanche discharge between said electrodes when voltage is applied between said anode and cathode.
References Cited (Backward Citations)
US3103589A
Cited
US1925648A
Cited
US2475603A
Cited
US2487797A
Cited
US2523779A
Cited
US2706366A
Cited
US2791712A
Cited
US2922911A
Cited
US3047761A
Cited
US3300677A
Cited
US3297896A
Cited
US3213312A
Cited
US3379928A
Cited
US3478205A
Cited
US3383538A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-11 | 1975-10-11 | 1976-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-11 | 1979-10-11 | 1980-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-11 | 1983-10-11 | 1984-04-11 | $7700.00 | Window Closed / Lapsed |