US5567929A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flat panel detector and image sensor
Assignee: University of Connecticut
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Filing: 1995-02-21
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Granted: 1996-10-22
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Expires: 2015-02-21
Abstract
Abstract A flat panel image sensor is provided by combining the photoconductive imaging electrode of a vidicon with a two dimensional array of cold cathode field emitters commonly used for flat panel Field Emission Display (FED) systems. The FED operates normally to emit electrons which are accelerated in prior art displays towards a luminescent phosphor to generate light output proportional to the cathode emission. Rather than accelerating towards a phosphor, electrons, in accordance with the principles of this invention, are accelerated towards a photoconductor layer to replace charge removed from the layer by an incident radiation pattern directed at the photoconductor layer through a layer of transparant, electrically-conducting material which serves as a radiation window. A large area, low cost, small, flat panel sensor is realized. The transparant, electrically-conducting layer may be partitioned to reduce stray capacitance for large area sensors and the partitioned, electrically-conducting layer permits a parallel readout mode of operation.
Inventors
- 👤 Donald R. Ouimette
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 01:01
CPC Classifications
H; H01; H01J; H01J40/00; H01J40/16; H01J31/00; H01J31/08; H01J31/26; H01J31/28; H01J31/34; H01J31/38; H01J2201/00; H01J2201/30; H01J2201/304; H01J2201/30403; H01J2231/00; H01J2231/50; H01J2231/50005; H01J2231/5001; H01J2231/50031; H01J2231/50036; H01J2231/50057; H01J2231/50068
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
155 words
A flat panel image sensor comprising a housing including first and second surfaces, said surfaces being parallel to one another and including a vacuum therebetween, said first surface including a window for radiation, said window comprising a layer of a radiation-transparant, electrically-conducting material, a photoconductor layer positioned on the underside of said electrically-conducting layer and being electrically coupled thereto, said photoconductor layer having a surface facing said vacuum, said first surface being positioned to receive a multi-pixel radiation image, said second surface comprising an array of electron beam sources, said sensor including means for impressing a voltage on said electrically-conducting layer for establishing a bias field across said photoconductor layer, and means for activating said electron beam sources in a manner to discharge consecutive charges on said photoconductor layer corresponding to consecutive pixel positions of said image, and read cut means connected to said electrically-conducting layer for reading out the signals produced by the discharges.
Claim 2
Dependent Claim
155 words
A flat panel image sensor comprising a housing including first and second surfaces, said surfaces being parallel to one another and including a vacuum therebetween, said first surface including a window for radiation, said window comprising a layer of a radiation-transparant, electrically-conducting material, a photoconductor layer positioned on the underside of said electrically-conducting layer and being electrically coupled thereto, said photoconductor layer having a surface facing said vacuum, said first surface being positioned to receive a multi-pixel radiation image, said second surface comprising an array of electron beam sources, said sensor including means for impressing a voltage on said electrically-conducting layer for establishing a bias field across said photoconductor layer, and means for activating said electron beam sources in a manner to discharge consecutive charges on said photoconductor layer corresponding to consecutive pixel positions of said image, and read cut means connected to said electrically-conducting layer for reading out the signals produced by the discharges.
Claim 3
Dependent Claim
17 words
A sensor as in claim 1 wherein said first surface includes a metallic layer transparant to X-rays.
Claim 4
Dependent Claim
24 words
A sensor as in claim 1 including a field mesh positioned in said vacuum in a plane parallel to said first and second surfaces.
Claim 5
Dependent Claim
22 words
A sensor as in claim 2 including a separate glass window for maintaining the vacuum between said first and second surfaces uniform.
Claim 6
Dependent Claim
13 words
A sensor as in claim 1 wherein said electrically-conducting material comprises tin oxide.
Claim 7
Dependent Claim
14 words
A sensor as in claim 1 wherein said electrically-conducting material comprises indium tin oxide.
Claim 8
Dependent Claim
11 words
A sensor as in claim 2 wherein said window comprises aluminum.
Claim 9
Dependent Claim
11 words
A sensor as in claim 2 wherein said window comprises beryllium.
Claim 10
Dependent Claim
36 words
A sensor as in claim 1 wherein said photoconductor layer comprises a high resistivity, electrically-insulating material which is photoconductive to incident energy photons directed at it's surface and provides charge storage in response to such photons.
Claim 11
Dependent Claim
48 words
A sensor as in claim 9 wherein said photoconductor layer is taken from a class of photoconductors consisting of thallium bromide, thallium iodide, thallium bromo-iodide, lead iodide, lead bromide, lead bromo-iodide, selenium, and composite sandwiches of the scintillating materials cesium iodide or phosphors against a light-sensitive photoconductor material.
Claim 12
Dependent Claim
20 words
A sensor as in claim 1 wherein said array of electron beams sources comprises an array of field emission tips.
Claim 13
Dependent Claim
56 words
A sensor as in claim 1 wherein said electrically-conducting layer is partitioned into stripes and said means for activating provides an electron beam in a manner to scan along the long axis of said stripes and scan said stripes in sequence for discharging consecutive areas of said photoconductor corresponding to pixels of an incident radiation image.
Claim 14
Dependent Claim
21 words
A sensor as in claim 12 wherein adjacent ones of said stripes are electrically connected in pairs to a common amplifier.
Claim 15
Dependent Claim
40 words
A sensor as in claim 13 including means for switching from a first pair of amplifiers to the next subsequent one of said pairs when said electron beam scanning along the center of a second stripe of said first pair.
Claim 16
Dependent Claim
30 words
A sensor as in claim 13 wherein said means for activating includes means for activating said electron beam sources in parallel and means for reading out said amplifiers in parallel.
Claim 17
Dependent Claim
81 words
A flat panel image sensor comprising a housing having first and second surfaces, said surfaces being parallel to one another and including a vacuum therebetween, said first surface including a window for radiation, said window comprising a layer of radiation transparant, electrically-conducting material, a photoconductor layer positioned on the underside of said electrically-conducting layer and being electrically coupled thereto, said photoconductor layer having a surface facing said vacuum, said second surface comprising an array of individual sources of an electron beam.
Claim 18
Dependent Claim
81 words
A flat panel image sensor comprising a housing having first and second surfaces, said surfaces being parallel to one another and including a vacuum therebetween, said first surface including a window for radiation, said window comprising a layer of radiation transparant, electrically-conducting material, a photoconductor layer positioned on the underside of said electrically-conducting layer and being electrically coupled thereto, said photoconductor layer having a surface facing said vacuum, said second surface comprising an array of individual sources of an electron beam.
Claim 19
Dependent Claim
41 words
A sensor as in claim 16 also including means for impressing a voltage on said electrically-conducting layer for establishing a bias field across said photoconductor layer and means for activating said impressing means in a sequence to scan said photoconductor surface.
Claim 20
Dependent Claim
116 words
A flat panel device comprising a housing having first and second surfaces, said surfaces being parallel to one another and including a vacuum therebetween, said first surface including a window for radiation, said window comprising a layer of radiation-transparant, electrically-conducting material, a photoconductor layer positioned on the underside of said electrically-conducting layer and being electrically coupled thereto, said photoconductor layer having a surface facing said vacuum, said second surface comprising an array of sources of electrons, said layer of electrically-conducting material being partitioned into stripes, said device also including a plurality of amplifiers and means for connecting said stripes in pairs to associated ones of said amplifiers and means for reading data from said amplifiers selectively.
Claim 21
Dependent Claim
116 words
A flat panel device comprising a housing having first and second surfaces, said surfaces being parallel to one another and including a vacuum therebetween, said first surface including a window for radiation, said window comprising a layer of radiation-transparant, electrically-conducting material, a photoconductor layer positioned on the underside of said electrically-conducting layer and being electrically coupled thereto, said photoconductor layer having a surface facing said vacuum, said second surface comprising an array of sources of electrons, said layer of electrically-conducting material being partitioned into stripes, said device also including a plurality of amplifiers and means for connecting said stripes in pairs to associated ones of said amplifiers and means for reading data from said amplifiers selectively.
References Cited (Backward Citations)
US5369268A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1999-10-22 | 2000-04-22 | 2000-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-10-22 | 2004-04-22 | 2004-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-10-22 | 2008-04-22 | 2008-10-22 | $7700.00 | Window Closed / Lapsed |