US4383169A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Luminescent screen devices
Assignee: Teledyne UK Ltd
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Filing: 1979-05-30
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Granted: 1983-05-10
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Expires: 1999-05-30
Abstract
Abstract The aluminium-backed phosphor layer on the output window of conventional image intensifier tubes of the photoemissive/luminescent screen type can be seriously damaged by the extremely high energy density pulse of electrons resulting from exposure of the tube to very bright light (such as a shell flash). The invention prevents or minimises the damage by placing in between and in contact with the phospher layer and the aluminium layer a layer of material (for example, potassium silicate) whose thermal properties are such as to cause it to act as a heat sink and so absorb most, if not all, of the thermal energy released by the electron pulse.
Inventors
- 👤 John E. U. Ashton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:20
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/20; H01J9/22; H01J9/221; H01J29/00; H01J29/02; H01J29/10; H01J29/18; H01J29/28
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
118 words
A light image-forming device of the sort wherein a source of electrons is stimulated to produce electrons which are then accelerated into contact with a luminescent screen which includes a layer of luminescent material constituting the electron-sensitive, light-emitting section thereof, which layer of luminescent material is provided with a backing layer of metal, so as to form a light image corresponding to the original stimulation of the electron source, wherein between and in contact with both said layer of luminescent material and said backing layer of metal is a layer of material whose thermal properties are such that it tends to act as a heat sink to absorb energy from high energy density pulses of electrons impinging thereon.
Claim 2
Dependent Claim
118 words
A light image-forming device of the sort wherein a source of electrons is stimulated to produce electrons which are then accelerated into contact with a luminescent screen which includes a layer of luminescent material constituting the electron-sensitive, light-emitting section thereof, which layer of luminescent material is provided with a backing layer of metal, so as to form a light image corresponding to the original stimulation of the electron source, wherein between and in contact with both said layer of luminescent material and said backing layer of metal is a layer of material whose thermal properties are such that it tends to act as a heat sink to absorb energy from high energy density pulses of electrons impinging thereon.
Claim 3
Dependent Claim
16 words
A device as claimed in claim 1 and wherein said backing layer of metal is aluminium.
Claim 4
Dependent Claim
19 words
A device as claimed in claim 1 and wherein the material forming said heat sink layer is a silicate.
Claim 5
Dependent Claim
14 words
A device as claimed in claim 4 and wherein said silicate is potassium silicate.
Claim 6
Dependent Claim
32 words
A device as claimed in claim 1 which is an image intensifier device and has at its output end said luminescent screen and at the opposite, input, end a photo emissive cathode.
Claim 7
Dependent Claim
16 words
A device as claimed in claim 5 and forming one module of a multi-stage image intensifier.
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) | 1986-05-09 | 1986-11-08 | 1987-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-05-09 | 1990-11-08 | 1991-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-05-09 | 1994-11-08 | 1995-05-10 | $7700.00 | Window Closed / Lapsed |