Patent US4170413A successfully refreshed from Google Patents.
US4170413A
Expired / Lapsed
US
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Device for stabilizing and increasing contrast potential in an electrophotographic copier
Assignee: Canon Production Printing Germany GmbH and Co KG
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Filing: 1978-06-08
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Granted: 1979-10-09
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Expires: 1998-06-08
Abstract
Abstract A device is disclosed which is useful in an electrophotographic copier for stabilizing and increasing contrast potential. The device is employed for extinguishing a recorded, electrostatic charge image. The device has one or more light sources which provide a spectral distribution comprising a first spectral range of maximum photoconductivity production and a radiation energy which is three to ten times a radiation energy present in a second spectral range. The second spectral range is located at a wavelength determined by a maximum of a product of photoconductivity production and penetration depth. An additional radiation energy distribution in remaining portions of the spectral distribution has a radiation energy not exceeding five to ten percent of the radiation energy of the first range.
Inventors
- 👤 Eberhard Bayer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:10
CPC Classifications
G; G03; G03G; G03G21/00; G03G21/06; G03G21/08
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
133 words
A device in an electrophotographic copier, said device comprising: extinguishing means for a recorded, electrostatic charge image; said extinguishing means including light source means having a spectral distribution; said spectral distribution comprising a first spectral range of maximum photoconductivity centered about a first wavelength and having a radiation energy which is 3 to 10 times a radiation energy present in a second spectral range determined by a maximum of a product of photoconductivity production and penetration depth and being centered about a second wavelength; a width of the first and second spectral ranges being approximately ±10% of the respective first and second wavelength; and an additional radiation energy distribution in remaining portions of the spectral distribution having a radiation energy not exceeding 5 to 10% of the radiation energy of the first range.
Claim 2
Independent Claim
133 words
A device in an electrophotographic copier, said device comprising: extinguishing means for a recorded, electrostatic charge image; said extinguishing means including light source means having a spectral distribution; said spectral distribution comprising a first spectral range of maximum photoconductivity centered about a first wavelength and having a radiation energy which is 3 to 10 times a radiation energy present in a second spectral range determined by a maximum of a product of photoconductivity production and penetration depth and being centered about a second wavelength; a width of the first and second spectral ranges being approximately ±10% of the respective first and second wavelength; and an additional radiation energy distribution in remaining portions of the spectral distribution having a radiation energy not exceeding 5 to 10% of the radiation energy of the first range.
Claim 3
Dependent Claim
38 words
A device as claimed in claim 1, characterized in that the light source means comprises a light source providing radiation energy for the second spectral range, said light source also emitting radiation of said additional radiation energy distribution.
Claim 4
Dependent Claim
20 words
A device as claimed in claim 2, characterized in that the radiation from said light source is substantially white light.
Claim 5
Dependent Claim
55 words
A device as claimed in claim 1 in which said light source means comprises a single radiation source producing radiation energies of the first and second spectral ranges and an associated filter producing said radiation energies of said first and second ranges and a limit for the radiation energy in said additional radiation energy distribution.
Claim 6
Dependent Claim
34 words
A device as claimed in claim 1, characterized in that said light source means comprises a first radiation source producing the first spectral range and a second radiation source producing the second spectral range.
Claim 7
Dependent Claim
163 words
An extinguishing device in an electrophotographic copier having a recorded electrostat charge image in a photoconductive layer, comprising: (a) extinguishing means for extinguishing the electrostatic charge image in the photoconductive layer; (b) said extinguishing means comprising a light source means with a spectral distribution comprising: (i) a first spectral range encompassing a first wavelength of maximum photoconductive layer photoconductivity production and having a first radiation energy; (ii) a second spectral range encompassing a second wavelength corresponding to a maximum of a product of photoconductive layer photoconductivity production and photoconductive layer penetration depth, and having a second radiation energy which is 3 to 10 times smaller than the first radiation energy; (iii) a width of the first and second spectral ranges respectively being approximately ±10% of the respective first and second wavelengths; and (iv) an additional radiation energy distribution in remaining portions of the spectral distribution having a radiation energy not exceeding 5 to 10% of the radiation energy of the first spectral range.
Claim 8
Dependent Claim
163 words
An extinguishing device in an electrophotographic copier having a recorded electrostat charge image in a photoconductive layer, comprising: (a) extinguishing means for extinguishing the electrostatic charge image in the photoconductive layer; (b) said extinguishing means comprising a light source means with a spectral distribution comprising: (i) a first spectral range encompassing a first wavelength of maximum photoconductive layer photoconductivity production and having a first radiation energy; (ii) a second spectral range encompassing a second wavelength corresponding to a maximum of a product of photoconductive layer photoconductivity production and photoconductive layer penetration depth, and having a second radiation energy which is 3 to 10 times smaller than the first radiation energy; (iii) a width of the first and second spectral ranges respectively being approximately ±10% of the respective first and second wavelengths; and (iv) an additional radiation energy distribution in remaining portions of the spectral distribution having a radiation energy not exceeding 5 to 10% of the radiation energy of the first spectral range.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-10-08 | 1983-04-09 | 1983-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-10-08 | 1987-04-09 | 1987-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-10-08 | 1991-04-09 | 1991-10-09 | $7700.00 | Window Closed / Lapsed |