US3880512A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image recording apparatus for electrophotographic film
Assignee: Coulter Information Systems Inc
•
Filing: 1973-08-17
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Granted: 1975-04-29
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Expires: 1993-08-17
Abstract
Abstract A system for impressing images on electrophotographic film provides apparatus for charging each film frame rapidly to a peak voltage determined by the prevailing light conditions of the image to be produced or recorded. After charging, means are provided for immediately exposing the frame to an image. In the preferred apparatus, means are provided for adjusting the time of exposure to a fixed period which is predetermined. Means are provided for applying toner to the exposed frame immediately after exposure in the presence of a bias field which propels the toner particles toward the film. Thereafter excess toner is removed from the film or leaves the frame and the remaining toner is fused to the surface of the film to form a permanent visible image on the film frame. An alternate form of the invention provides means for transferring the toned image to an acceptor member where it is fixed. The apparatus includes structure which enables the processes above described to be carried out along a line or in a rotary arrangement. Electronic and electrical circuitry are provided for accomplishing the various functions in proper sequence and timing. The apparatus is arranged to carry out the processes at points on the dark decay portion of the characteristic discharge curve for the particular film so that the resultant image has high resolution, optimum contrast and a substantially continuous gray scale. The quality is as good as if not better than photographic quality. The sensitivity of the film is controlled by the level to which it is charged and circuitry provided enables this to be automatically accomplished. The level in turn is chosen on the basis of the average light of the image or scene to be recorded and means are provided to accomplish this automatically or manually.
Inventors
- 👤 Manfred R Kuehnle
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 00:31
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/22
Claims Analysis
Total Claims: 41
Claim 1
Independent Claim
259 words
Apparatus for recording images of a projected scene or the like on the photoconductive coating of an electrophotographic member which comprises: A. means for projecting the image onto the coating and including controllable light passing means to enable controlled exposure of said coating, B. means for electrically charging the coating in darkness at a rapid rate to a peak potential charge, C. control means for operating the light passing means to effect exposure of the photoconductive coating to the projected image, D. means for applying toner to the coating to render a latent charge image visible, E. means for measuring the light intensity of the projected image before exposure and deriving a first signal representative of said intensity, F. means for measuring the magnitude of the charge on the coating due to said charging and deriving a second signal representative of said magnitude, G. means coupling the charging means with said control means to initiate exposure when said peak charge has been reached, H. means for limiting one of i. the extent of exposure due to operation of the light passing means to achieve a predetermined exposure and ii. the operation of the charging means to provide a peak charge of predetermined potential, and I. means for comparing the first and second signals and disabling that one of said charging means and light passing means which is not limited in response to the relationship represented by such comparison when the said one which is not limited reaches a value previously determined as substantially optimum for the light intensity measured.
Claim 2
Dependent Claim
259 words
Apparatus for recording images of a projected scene or the like on the photoconductive coating of an electrophotographic member which comprises: A. means for projecting the image onto the coating and including controllable light passing means to enable controlled exposure of said coating, B. means for electrically charging the coating in darkness at a rapid rate to a peak potential charge, C. control means for operating the light passing means to effect exposure of the photoconductive coating to the projected image, D. means for applying toner to the coating to render a latent charge image visible, E. means for measuring the light intensity of the projected image before exposure and deriving a first signal representative of said intensity, F. means for measuring the magnitude of the charge on the coating due to said charging and deriving a second signal representative of said magnitude, G. means coupling the charging means with said control means to initiate exposure when said peak charge has been reached, H. means for limiting one of i. the extent of exposure due to operation of the light passing means to achieve a predetermined exposure and ii. the operation of the charging means to provide a peak charge of predetermined potential, and I. means for comparing the first and second signals and disabling that one of said charging means and light passing means which is not limited in response to the relationship represented by such comparison when the said one which is not limited reaches a value previously determined as substantially optimum for the light intensity measured.
Claim 3
Dependent Claim
31 words
Apparatus as claimed in claim 1 in which the toner applying means include an electrical bias circuit for propelling toner to the coating to achieve even distribution thereof on said coating.
Claim 4
Dependent Claim
55 words
Apparatus as claimed in claim 1 in which the toner applying means include an electrical bias circuit for propelling toner to the coating to achieve an even distribution thereof on said coating, the voltage of the bias being capable of variation in accordance with the magnitude of charge reached by the charging of said coating.
Claim 5
Dependent Claim
56 words
Apparatus as claimed in claim 1 in which the light intensity measuring means comprise a photoresponsive device arranged to receive the projected image before eXposure and the charge measuring means comprise a voltage responsive device and in which the comparing means comprise circuitry connected to the devices during the charging period and continuously making the comparison.
Claim 6
Dependent Claim
59 words
Apparatus as claimed in claim 1 in which the charging means include a corona producing member and a corona power supply, means are provided for connecting the power supply to the corona producing member and the disabling means comprise a switch in said connecting means which is closed to commence charging and opened when the peak charge is reached.
Claim 7
Dependent Claim
52 words
Apparatus as claimed in claim 1 in which said coupling means include signal producing means rendered operative upon the coating achieving said peak charge to produce a third signal, said control means for operating the light passing means being rendered operative by said third signal to commence the exposure of said coating.
Claim 8
Dependent Claim
80 words
Apparatus as claimed in claim 1 in which said coupling means include signal producing means rendered operative upon the coating achieving said peak charge to produce a third signal, sald control means for operating the light passing means being rendered operative by said third signal to commence the exposure of said coating and said last mentioned control means being arranged to complete the exposure in a fixed time irrespective of the time required to charge the coating to said peak.
Claim 9
Dependent Claim
120 words
Apparatus as claimed in claim 1 in which said coupling means include signal producing means rendered operative upon the coating achieving said peak charge to produce a third signal, said control means for operating the light passing means being rendered operative by said third signal to commence the exposure of said coating, a variable time control circuit connected with said charge magnitude measuring means and responsive to the surface charge potential reached by said coating at a dark area during exposure to produce a fourth signal, the last mentioned circuit being coupled with said light passing means operating control means so that the fourth signal will disable the same when the coating charge decays to a predetermined level during exposure.
Claim 10
Dependent Claim
39 words
Apparatus as claimed in claim 1 in which signal producing means are provided and rendered operative upon completion of the time of exposure to produce a toning signal, said toner applying means being rendered operative by said toning signal.
Claim 11
Dependent Claim
66 words
Apparatus as claimed in claim 1 in which signal producing means are provided and rendered operative upon completion of the time of exposure to produce a toning signal, said toner applying means being rendered operative by said toning signal and having structure to provide for continuation of the toning for a predetermined time period at the end of which said toner applying means is rendered inoperative.
Claim 12
Dependent Claim
94 words
Apparatus as claimed in claim 1 in which signal producing means are provided and rendered operative upon the completion of the time of exposure to produce a toning signal, said toner applying means being rendered operative by said toning signal and having structure to provide for continuation of the toning for a predetermined time period at the end of which said toner applying means is rendered inoperative, said last mentioned structure including control means for adjustingg the time of toning inversely as the magnitude of the charge reached by the charging of said coating.
Claim 13
Dependent Claim
20 words
Apparatus as claimed in claim 1 in which means are provided for fusing the toner to the coating after toning.
Claim 14
Dependent Claim
60 words
Apparatus as claimed in claim 1 in which means are provided for fusing the toner to the coating after toning and in which signal producing means are provided and rendered operative upon the completion of the toning period to produce a fusing signal, said toner fusing means including structure for rendering the toner fusing means operative by said fusing signal.
Claim 15
Dependent Claim
93 words
Apparatus as claimed in claim 1 in which first signal producing means are provided and rendered operative upon thE completion of the time of charging to produce a third signal, second signal producing means are provided and rendered operative upon the completion of the time of exposure to produce a fourth signal, said control means for operating said light passing means being rendered operative by said third signal to commence the exposure of said coating and said toner applying means rendered operative by said fourth signal to commence the toning of said coating.
Claim 16
Dependent Claim
145 words
Apparatus as claimed in claim 1 in which means are provided for fusing the toner to the coating after toning, first signal producing means are provided and rendered operative upon the completion of the time of charging to produce a third signal, second signal producing means are provided and rendered operative upon the completion of the time of exposure to produce a fourth signal, third signal producing means are provided and rendered operative upon the completion of the time of toning to produce a fifth signal, the third, fourth and fifth signals being connected respectively to the control means for operating the light blocking member, the toner applying means and the fusing means to enable the same in sequence each upon the completion of operation of the previous one, there being means for establishing the time of operation of each of the latter three means.
Claim 17
Dependent Claim
51 words
Apparatus as claimed in claim 1 in which the comparing and controlling means are additionally constructed to provide for the disabling of the charging means in such relation to the light intensity that the coating is charged to a peak potential which varies inversely as the light intensity for different images.
Claim 18
Dependent Claim
51 words
Apparatus as claimed in claim 1 in which the charging means, light passing means and toner applying means are all distributed around peripheral portions of a rotary support member and means are provided for moving the electrophotographic member in the manner of an elongate belt in engagement with said peripheral portions.
Claim 19
Dependent Claim
47 words
Apparatus as claimed in claim 17 which includes an elongate, belt-like electrophotographic member, said member being made up of a plurality of frames along the length thereof and each frame is successively brought into operative relationship with the respective means during movement relative to said support member.
Claim 20
Dependent Claim
18 words
Apparatus as claimed in claim 17 in which toner fusing means are included distributed around the peripheral portions.
Claim 21
Dependent Claim
48 words
Apparatus as claimed in claim 19 in which the electrophotographic member is elongate and belt-like and is included and comprises a plurality of frames along said belt-like member and each frame is successively brought into operative relationship with the respective means during movement relative to the support member.
Claim 22
Dependent Claim
31 words
Apparatus as claimed in claim 16 in which the toner applying means include an electrical bias circuit for propelling toner to the coating to achieve even distribution thereof on said coating.
Claim 23
Dependent Claim
56 words
Apparatus as claimed in claim 16 in which the light intensity measuring means comprise a photoresponsive device arranged to receive the projected image before exposure and the charge measuring means comprise a voltage responsive device and in which the comparing means comprise circuitry connected to the devices during the charging period and continuously making the comparison.
Claim 24
Dependent Claim
58 words
Apparatus as claimed in claim 16 in which the charging means include a corona producing member and a corona power supply, means are provided for connecting the power supply to the corona producing member and the controlling means comprise a switch in said connecting means which is closed commence charging and opened when the optimum relationship is reached.
Claim 25
Dependent Claim
52 words
Apparatus as claimed in claim 16 in which said coupling means include signal producing means rendered operative upon the coating achieving said peak charge to produce a third signal, said control means for operating the light passing means being rendered operative by said third signal to commence the exposure of said coating.
Claim 26
Dependent Claim
80 words
Apparatus as claimed in claim 16 in which said coupling means include signal producing means rendered operative upon the coating achieving said peak charge to produce a third signal, said control means for operating the light passing means being rendered operative by said third signal to commence the exposure of said coating and said last mentioned control means being arranged to complete the exposure in a fixed time irrespective of the time required to charge the coating to said peak.
Claim 27
Dependent Claim
39 words
Apparatus as claimed in claim 16 in which signal producing means are provided and rendered operative upon completion of the time of exposure to produce a toning signal, said toner applying means being rendered operative by said toning signal.
Claim 28
Dependent Claim
66 words
Apparatus as claimed in claim 16 in which signal producing means are provided and rendered operative upon completion of the time of exposure to produce a toning signal, said toner applying means being rendered operative by said toning signal and having structure to provide for continuation of the toning for a predetermined time period at the end of which said toner applying means is rendered inoperative.
Claim 29
Dependent Claim
94 words
Apparatus as claimed in claim 16 in which signal producing means are provided and rendered operative upon the completion of the time of exposure to produce a toning signal, said toner applying means being rendered operative by said toning signal and having structure to provide for continuation of the toning for a predetermined time period at the end of which said toner applying means is rendered inoperative, said last mentioned structure including control means for adjusting the time of toning inversely as the magnitude of the charge reached by the charging of said coating.
Claim 30
Dependent Claim
20 words
Apparatus as claimed in claim 16 in which means are provided for fusing the toner to the coating after toning.
Claim 31
Dependent Claim
60 words
Apparatus as claimed in claim 16 in which means are provided for fusing the toner to the coating after toning and in which signal producing means are provided and rendered operative upon the completion of the toning period to produce a fusing signal, said toner fusing means including structure for rendering the toner fusing means operative by said fusing signal.
Claim 32
Dependent Claim
93 words
Apparatus as claimed in claim 16 in which first signal producing means are provided and rendered operative upon the completion of the time of charging to produce a third signal, second signal producing means are provided and rendered operative upon completion of the time of exposure to produce a fourth signal, said control means for operating said light passing means being rendered operative by said third signal to commence the exposure of said coating and said toner applying means being rendered operative by said fourth signal to commence the toning of said coating.
Claim 33
Dependent Claim
145 words
Apparatus as claimed in claim 16 in which means are provided for fusing the toner to the coating after toning, first signal producing means are provided and rendered operative upon the completion of the time of charging to produce a third signal, second signal producing means are provided and rendered operative upon the completion of the time of exposure to produce a fourth signal, third signal producing means are provided and rendered operative upon the completion of the time of toning to produce a fifth signal, the third, fourth and fifth signals being connected respectively to the control means for operating the light passing means, the toner applying means and the fusing means to enable the same in sequence each upon the completion of operation of the previous one, there being means for establishing the time of operation of each of the latter three means.
Claim 34
Dependent Claim
283 words
In apparatus for recording images of a projected scene or the like on a photoconductive coating of an electrophotographic member which apparatus includes means for projecting an image onto said coating and a shutter and shutter mechanism for timed exposure of said coating by projection of said image, means fOr maintaining a frame of said coating in darkness before exposure, means for charging the frame in darkness and including an electrical power circuit connected to said charging means and switch means for rendering operative and disabling said power circuit to start and stop operation of said charging means, and means for toning the frame after exposure thereof, the invention herein which comprises means for adjusting the sensitivity of said frame in accordance with the average light of the projected image, said sensitivity adjusting means comprising: A. light sensing means for sensing the intensity of the light projecting onto the frame before exposure and providing a first output signal which is related to said intensity, B. surface charge potential sensing means for sensing the surface charge potential of the frame in darkness prior to exposure and providing a second output signal which is related to said surface charge potential at any instant of charging, C. means for comparing the first and second output signals and developing a charge control signal representative of their relationship and D. means coupling said charge control signal to the switch means to disable the power circuit at a time after it has been previously rendered operative when the said relationship reaches a certain value predetermined for a particular light intensity to provide a peak surface charge potential that represents the optimum sensitivity of the coating for that light intensity.
Claim 35
Dependent Claim
283 words
In apparatus for recording images of a projected scene or the like on a photoconductive coating of an electrophotographic member which apparatus includes means for projecting an image onto said coating and a shutter and shutter mechanism for timed exposure of said coating by projection of said image, means fOr maintaining a frame of said coating in darkness before exposure, means for charging the frame in darkness and including an electrical power circuit connected to said charging means and switch means for rendering operative and disabling said power circuit to start and stop operation of said charging means, and means for toning the frame after exposure thereof, the invention herein which comprises means for adjusting the sensitivity of said frame in accordance with the average light of the projected image, said sensitivity adjusting means comprising: A. light sensing means for sensing the intensity of the light projecting onto the frame before exposure and providing a first output signal which is related to said intensity, B. surface charge potential sensing means for sensing the surface charge potential of the frame in darkness prior to exposure and providing a second output signal which is related to said surface charge potential at any instant of charging, C. means for comparing the first and second output signals and developing a charge control signal representative of their relationship and D. means coupling said charge control signal to the switch means to disable the power circuit at a time after it has been previously rendered operative when the said relationship reaches a certain value predetermined for a particular light intensity to provide a peak surface charge potential that represents the optimum sensitivity of the coating for that light intensity.
Claim 36
Dependent Claim
31 words
The invention as claimed in claim 33 in which the sensitivity adjusting means is arranged to provide peak values which vary inversely as the values of light intensity for different images.
Claim 37
Dependent Claim
16 words
Apparatus as claimed in claim 1 in which said last mentioned one comprise said charging means.
Claim 38
Dependent Claim
17 words
Apparatus as claimed in claim 1 in which said last mentioned one comprise said light passing means.
Claim 39
Dependent Claim
71 words
Apparatus as claimed in claim 36 in which the charging means are constructed to provide a peak charge which is a predetermined magnitude and said comparing means are operative to produce a fourth signal when said optimum value is reached, said control means for operating said light passing means being coupled with said comparing means to disable said light passing means and discontinue the exposure in response to the fourth signal.
Claim 40
Dependent Claim
23 words
Apparatus as claimed in claim 8 in which the charging means are constructed to provide a peak charge which is a predetermined magnitude.
Claim 41
Dependent Claim
37 words
The invention as claimed in claim 33 which includes the shutter mechanism and in which said last means also coupled said charge control signal to said shutter mechanism to commence exposure immediately that said relationship is reached.
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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) | 1978-04-28 | 1978-10-28 | 1979-04-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-28 | 1982-10-28 | 1983-04-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-28 | 1986-10-28 | 1987-04-29 | $7700.00 | Window Closed / Lapsed |