US3594683A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photoconductive cell
Assignee: Canon Inc
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Filing: 1968-02-21
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Granted: 1971-07-20
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Expires: 1988-02-21
Abstract
Abstract This invention provides a photoconductive cell and means for producing the same for use in photometry having the specific property that current flowing through the cell is substantially proportional to the logarithm of the intensity of illumination of luminous flux. The electrodes of the cell have a resistance value corresponding to a value intermediate the value of specific resistance which the photoconductive body exhibits between the upper and lower limits of the photometric range. The electrodes of the cell have no rectifying property or only a slight rectifying property relative to the photoconductive body, and when it is difficult to obtain the desired specific resistance from a production point of view or for any other reason, material of the electrodes may be selected from one or more kinds of materials whose work function is the same or similar to that of the photoconductive body.
Inventors
- 👤 Kazuhiko Ihaya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:27
CPC Classifications
C; C23; C23C; C23C14/00; H; H10; H10F; H10F30/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
63 words
A photoconductive cell comprising a substrate, a layer of photoconductive material on said substrate, and electrodes on said layer, said electrodes being characterized in that at least a part thereof has a work function similar to that of said photoconductive material and a specific resistance intermediate the highest and lowest specific resistances of said layer over the intended photometric range of the cell.
Claim 2
Dependent Claim
63 words
A photoconductive cell comprising a substrate, a layer of photoconductive material on said substrate, and electrodes on said layer, said electrodes being characterized in that at least a part thereof has a work function similar to that of said photoconductive material and a specific resistance intermediate the highest and lowest specific resistances of said layer over the intended photometric range of the cell.
Claim 3
Dependent Claim
26 words
A photoconductive cell according to claim 1, wherein said part of said electrodes consists of a material which is essentially a semiconductor having substantially no photoconductivity.
Claim 4
Dependent Claim
39 words
A photoconductive cell according to claim 2, wherein said semiconductor material consists essentially of one or more materials selected from the group consisting of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, GaP, InSb, Ge, Si, anthracene, and polyvinyl carbazole.
Claim 5
Dependent Claim
58 words
A photoconductive cell according to claim 2, wherein said photoconductive material consists essentially of one or more compounds selected from the group consisting of sulfides, selenides, tellurides, and oxides of zinc and cadmium; and said semiconductor material consists essentially of one or more materials selected from the group consisting of ZnS, ZnSe, CdS, ZnTe, CdSe, CdTe and ZnO.
Claim 6
Dependent Claim
82 words
A photoconductive cell comprising a substrate, a layer of photoconductive material on said substrate, and electrodes on said layer, said electrodes being characterized in that at least a part thereof consists of a material which is essentially the same as that constituting said layer but produced so as to be at least substantially nonphotoconductive, and said part of said electrodes has a specific resistance intermediate the highest and lowest specific resistances of said layer over the intended photometric range of the cell.
Claim 7
Dependent Claim
82 words
A photoconductive cell comprising a substrate, a layer of photoconductive material on said substrate, and electrodes on said layer, said electrodes being characterized in that at least a part thereof consists of a material which is essentially the same as that constituting said layer but produced so as to be at least substantially nonphotoconductive, and said part of said electrodes has a specific resistance intermediate the highest and lowest specific resistances of said layer over the intended photometric range of the cell.
Claim 8
Dependent Claim
43 words
A photoconductive cell according to claim 5, wherein the basic material of both said layer and said part of the electrodes is selected from the group consisting of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, GaP, InSb, Ge, Si, anthracene, and polyvinyl carbazole.
Claim 9
Dependent Claim
37 words
A photoconductive cell according to claim 5, wherein the basic material of both saId layer and said part of the electrodes is selected from the group consisting of sulfides, selenides, tellurides, and oxides of zinc and cadmium.
Claim 10
Dependent Claim
38 words
A photoconductive cell according to claim 5, wherein the basic material of both said layer and said part of the electrodes is selected from the group consisting of ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, ZnO, and mixtures thereof.
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) | 1974-07-19 | 1975-01-18 | 1975-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-19 | 1979-01-18 | 1979-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-19 | 1983-01-18 | 1983-07-20 | $7700.00 | Window Closed / Lapsed |