Apparatus for large scale screen display of images

Claim 3

The system as claimed in claim 1 in which said controlling means comprise means for measuring and comparing the charge potential on the film and the incident light intensity and control circuit means for providing a signal upon said charging device for controlling the applied charge.

Claim 4

The system as claimed in claim 2 in which said control circuit means includes means for disabling the charging device and said exposing means is operable immediately after the operation of said disabling means.

Claim 5

The system as claimed in claim 2 in which said potential measuring means comprise a voltage measuring device to derive a first signal which is a varying voltage which rises as the charge increases, said light intensity measuring means and deriving means include a photocell connected to an adjusting circuit whose parameters are adjusted to provide an output voltage having a predetermined characteristic for different values of light intensity, said last-mentioned output voltage being constant for any value of light intensity and comprising a second signal, said comparing means including a differential amplifier arranged in the control circuit to produce an output signal only when its two input signals are equal, said output signal of said differential amplifier comprises the third signal and occurs only when the first signal has risen to equal the second signal.

Claim 6

The system as claimed in claim 4 in which said third signal is connected to operate said blind mechanism for exposing the film member, and means are provided for timing the exposure period.

Claim 7

The system as claimed in claim 5 and means for timing the toning period in a predetermined relationship to the measured light intensity, the time of toning varying generally inversely with light intensity.

Claim 8

The system as claimed in claim 5 and said timing means also being operable upon said toning means for timing the toning period in a predetermined relationship relative to the surface potential.

Claim 9

The system as claimed in claim 1 and means operating said toning means immediately after exposure of the film member and means for disabling said toning means.

Claim 10

The system as claimed in claim 1 in which said exposing means comprise a blind mechanism arranged interposed between said means for projecting and the charging device and means for operating the blind mechanism to permit passage therepast of the light pattern representing said scene when said selected potential value is reached.

Claim 11

The system as claimed in claim 1 and means for applying a bias voltage to the toner during the toning period.

Claim 12

The system as claimed in claim 1 in which said carrier means comprise a carrier disk arranged for stepwise rotary movement, said stations being disposed at spaced locations along the circumferential path of said disk and means to establish a lighttight condition during the period while the film member is at the first station whereby the film member is charged and toned in darkness.

Claim 13

The system as claimed in claim 1 in which said controlling means include photoresponsive means for measuring the light intensity and positioned to intercept at least some of the light which is projected onto the film member.

Claim 14

The system as claimed in claim 1 in which said controlling means comprise transparent photoresponsive means for measuring light intensity and interposed in the light path so as to intercept the light projected onto the film member but to permit most of the light to pass through.

Claim 23

The system as claimed in claim 17 in which said control circuit means include means operating to disable the charging device and means operable immediately subsequent to the operation of said disabling means to expose the film member.

Claim 24

The system as claimed in claim 17 in which said exposure means comprise a blind mechanism arranged between said optical train and the charging device and means for operating the blind mechanism to permit passage therepast of a light pattern representing said scene when said selected potential value is reached.

Claim 25

The system as claimed in claim 19 in which said third signal is connected to enable said blind mechanism for exposing the film member, and means are provided for timing the exposure period.

Claim 26

The system as claimed in claim 20 in which there are means for timing the toning period in a predetermined relationship to the measured light intensity, the time of toning varying generally inversely with light intensity.

Claim 27

The system as claimed in claim 20 and said timer means also operable upon said toning means for timing the toning period in a predetermined relationship relative to the surface potential.

Claim 28

The system as claimed in claim 17 and means for applying a bias voltage to the toner during the toning period.

Claim 29

The system as claimed in claim 17 in which the means for measuring the light intensity comprise photoresponsive means located on the interior of the housing and arranged to intercept at least some of the light which is projected onto the film member.

Claim 34

optical train means for receiving an image from said source and projecting said image upon the film member; and 2. means for charging, exposing and toning the film member successively while the film member is immobilized until toning is completed to form a temporarily visible projectable transparency of said image; ii. a projection station, including a light source and projecting means, for applying the image from said transparency to a receptor surface in large scale display; and iii. an erase station having means for removing all toner from said transparency to provide a clean film member for reuse at said recording station; E. said recording station includes a housing structure having said means for charging, exposing and toning disposed therein, and means for defining a lighttight enclosure while the film member is positioned at said recording station during formation of the projectable transparency, and F. said carrier means comprise a carrier disk arranged for rotary movement stepwise from station to station about a shaft, each of said stations being disposed at spaced locations along the periphery of said disk and said means to establish a lighttight enclosure being on the housing and the disk said charging and toning being performed in darkness.

Claim 35

optical train means for receiving an image from said source and projecting said image upon the film member; and 2. means for charging, exposing and toning the film member successively while the film member is immobilized until toning is completed to form a temporarily visible projectable transparency of said image; ii. a projection station, including a light source and projecting means, for applying the image from said transparency to a receptor surface in large scale display; and iii. an erase station having means for removing all toner from said transparency to provide a clean film member for reuse at said recording station; E. said recording station includes a housing structure having said means for charging, exposing and toning disposed therein, and means for defining a lighttight enclosure while the film member is positioned at said recording station during formation of the projectable transparency, and F. said carrier means comprise a carrier disk arranged for rotary movement stepwise from station to station about a shaft, each of said stations being disposed at spaced locations along the periphery of said disk and said means to establish a lighttight enclosure being on the housing and the disk said charging and toning being performed in darkness.

Claim 36

The system as claimed in claim 26 in which said carrier disk has at least one window formed therein, said film member mounted within said window, said window having a surrounding frame and said means establishing a lighttight condition includes the surrounding frame on the disk cooperating with the said housing to effect said condition when the window of the carrier disk is aligned with the optical train means at the first station.

Claim 39

optical train means for receiving an image from said source and projecting said image upon the film member; and 2. means for charging, exposing and toning the film member successively while the film member is immobilized until toning is completed to form a temporarily visible projectable transparency of said image; ii. a projection station, including a light source and projecting means, for applying the image from said transparency to a receptor surface in large scale display; and iii. an erase station having means for removing all toner from said transparency to provide a clean film member for reuse at said recording station, and E. said carrier means comprise a carrier disk having means for mounting the film thereon, said mounting means comprise a window carrying said film member and having an area which is in darkness notwithstanding the projection of the light pattern onto the major portion of the film surface so that said area is charged during operation of the charging device, and measuring means disposed in position to measure the surface potential of said area of the film member.

Claim 40

optical train means for receiving an image from said source and projecting said image upon the film member; and 2. means for charging, exposing and toning the film member successively while the film member is immobilized until toning is completed to form a temporarily visible projectable transparency of said image; ii. a projection station, including a light source and projecting means, for applying the image from said transparency to a receptor surface in large scale display; and iii. an erase station having means for removing all toner from said transparency to provide a clean film member for reuse at said recording station, and E. said carrier means comprise a carrier disk having means for mounting the film thereon, said mounting means comprise a window carrying said film member and having an area which is in darkness notwithstanding the projection of the light pattern onto the major portion of the film surface so that said area is charged during operation of the charging device, and measuring means disposed in position to measure the surface potential of said area of the film member.

Claim 43

optical train means for receiving an image from said source and projecting said image upon the film member; and 2. means for charging, exposing and toning the film member successively while the film member is immobilized until toning is completed to form a temporarily visible projectable transparency of said image; ii. a projection station, including a light source and projecting means, for applying the image from said transparency to a receptor surface in large scale display; and iii. an erase station having means for removing all toner from said transparency to provide a clean film member for reuse at said recording station, E. a lighttight housing structure accommodating said means for charging, exposing and toning being disposed within said enclosure and including. a charging device for charging the coating of said film member sufficiently to raise the surface potential thereof to a selected potential value, means intermediate said optical train and said charging device for exposing said film member to said pattern only when said potential value is reached, means for applying toner to the latent image formed on the film member subsequent to exposure thereof, means for measuring and comparing the charge potential on the coating of the film and the incident light intensity, and control circuit means operable upon said charging device for controlling the applied charge in relation to said measured light intensity; and F. the means for measuring the light intensity comprise transparent photoresponsive means interposed in the light path at the first station.

Claim 44

optical train means for receiving an image from said source and projecting said image upon the film member; and 2. means for charging, exposing and toning the film member successively while the film member is immobilized until toning is completed to form a temporarily visible projectable transparency of said image; ii. a projection station, including a light source and projecting means, for applying the image from said transparency to a receptor surface in large scale display; and iii. an erase station having means for removing all toner from said transparency to provide a clean film member for reuse at said recording station, E. a lighttight housing structure accommodating said means for charging, exposing and toning being disposed within said enclosure and including. a charging device for charging the coating of said film member sufficiently to raise the surface potential thereof to a selected potential value, means intermediate said optical train and said charging device for exposing said film member to said pattern only when said potential value is reached, means for applying toner to the latent image formed on the film member subsequent to exposure thereof, means for measuring and comparing the charge potential on the coating of the film and the incident light intensity, and control circuit means operable upon said charging device for controlling the applied charge in relation to said measured light intensity; and F. the means for measuring the light intensity comprise transparent photoresponsive means interposed in the light path at the first station.

Claim 47

optical train means for receiving an image from said source and projecting said image upon the film member; and 2. means for charging, exposing and toning the film member successively while the film member is immobilized until toning is completed to form a temporarily visible projectable transparency of said image; ii. a projection station, including a light source and projecting means, for applying the image from said transparency to a receptor surface in large scale display; and iii. an erase station having means for removing all toner from said transparency to provide a clean film member for reuse at said recording station, E. a lighttight housing structure accomodating said means for charging, exposing and toning being disposed within said enclosure and including, a charging device for charging the coating of said film member sufficiently to raise the surface potential thereof to a selected potential value, means intermediate said optical train and said charging device for exposing said film member to said pattern only when said potential value is reached, means for applying toner to the latent image formed on the film member subsequent to exposure thereof, means for measuring and comparing the charge potential on the coating of the film and the incident light intensity, and control circuit means operable upon said charging device for controlling the applied charge in relation to said measured light intensity, and F. the means for measuring the light intensity comprise a transparent photocell, the optical train including at least one lens and the photocell is coated onto a surface of said lens.

Claim 48

optical train means for receiving an image from said source and projecting said image upon the film member; and 2. means for charging, exposing and toning the film member successively while the film member is immobilized until toning is completed to form a temporarily visible projectable transparency of said image; ii. a projection station, including a light source and projecting means, for applying the image from said transparency to a receptor surface in large scale display; and iii. an erase station having means for removing all toner from said transparency to provide a clean film member for reuse at said recording station, E. a lighttight housing structure accomodating said means for charging, exposing and toning being disposed within said enclosure and including, a charging device for charging the coating of said film member sufficiently to raise the surface potential thereof to a selected potential value, means intermediate said optical train and said charging device for exposing said film member to said pattern only when said potential value is reached, means for applying toner to the latent image formed on the film member subsequent to exposure thereof, means for measuring and comparing the charge potential on the coating of the film and the incident light intensity, and control circuit means operable upon said charging device for controlling the applied charge in relation to said measured light intensity, and F. the means for measuring the light intensity comprise a transparent photocell, the optical train including at least one lens and the photocell is coated onto a surface of said lens.

Claim 49

Apparatus for temporarily recording a light pattern on electrophotographic film having a photoconductive coating and projecting said recorded light pattern in a large scale display upon a screen surface, said apparatus comprising: carrier means for holding at least one electrophotographic film member, a housing providing a lighttight enclosure and arranged to receive said electrophotographic film member in a lighttight relationship therewith, said film member having a photoconductive coating, a light pattern source exterior of said housing, projection means exterior of said housing arranged to apply said light pattern to said photoconductive coating, means within the housing proximate to said film member for charging the coating while same is in darkness, means for sensing the absolute potential of the charged coating and simultaneously, for sensing the flux of said light pattern and deriving respective signals from the potential and flux, a control circuit operated by said signals and having a predetermined characteristic which provides an output signal for any level of light flux when the charge potential sensed reaches a chosen value corresponding to any particular flux level and built into said characteristic, means driven by the output signal of the control circuit to disable said charging means and simultaneously to expose said charged coating to said light pattern, means enclosure for applying toner to the film member subsequent to exposure thereof, means for adjusting the time of toning and disabling said toner means after a predetermined time interval, both said film member and said means for charging, exposing and toning being immobilized one relative to the other throughout the charging, exposure and toning, a projector arrangement, including a light source and an optical train, arranged spaced from said housing for receiving the toned electrophotographic film member and capable of projecting the recorded light pattern upon the screen surface, toner removal means arranged spaced from said projector means and adapted to receive said toned electrophotographic film subsequent to projection for removal of all toner therefrom and means for stepwise translating said carrier means to bring said electrophotographic film member successively to said housing, said projection means, said toner removal means and again to said housing in that order, said housing accommodating said means for charging, exposing and toning, said housing including a wall having window means formed therein for transmitting the projected light pattern representative of said scene to the film member when the same is aligned therewith, and said means for charging, exposing and toning includes a charging device proximate said window means for charging the coating of said film member sufficiently to raise the surface potential thereof to a selected potential value, means intermediate said optical train and said charging device for exposing said film member to said pattern only when said potential value is reached, means proximate to said window for applying toner to the film member subsequent to exposure, and means for controlling the applied charge on the film in relation to the incident light intensity.

Claim 50

Apparatus for temporarily recording a light pattern on electrophotographic film having a photoconductive coating and projecting said recorded light pattern in a large scale display upon a screen surface, said apparatus comprising: carrier means for holding at least one electrophotographic film member, a housing providing a lighttight enclosure and arranged to receive said electrophotographic film member in a lighttight relationship therewith, said film member having a photoconductive coating, a light pattern source exterior of said housing, projection means exterior of said housing arranged to apply said light pattern to said photoconductive coating, means within the housing proximate to said film member for charging the coating while same is in darkness, means for sensing the absolute potential of the charged coating and simultaneously, for sensing the flux of said light pattern and deriving respective signals from the potential and flux, a control circuit operated by said signals and having a predetermined characteristic which provides an output signal for any level of light flux when the charge potential sensed reaches a chosen value corresponding to any particular flux level and built into said characteristic, means driven by the output signal of the control circuit to disable said charging means and simultaneously to expose said charged coating to said light pattern, means enclosure for applying toner to the film member subsequent to exposure thereof, means for adjusting the time of toning and disabling said toner means after a predetermined time interval, both said film member and said means for charging, exposing and toning being immobilized one relative to the other throughout the charging, exposure and toning, a projector arrangement, including a light source and an optical train, arranged spaced from said housing for receiving the toned electrophotographic film member and capable of projecting the recorded light pattern upon the screen surface, toner removal means arranged spaced from said projector means and adapted to receive said toned electrophotographic film subsequent to projection for removal of all toner therefrom and means for stepwise translating said carrier means to bring said electrophotographic film member successively to said housing, said projection means, said toner removal means and again to said housing in that order, said housing accommodating said means for charging, exposing and toning, said housing including a wall having window means formed therein for transmitting the projected light pattern representative of said scene to the film member when the same is aligned therewith, and said means for charging, exposing and toning includes a charging device proximate said window means for charging the coating of said film member sufficiently to raise the surface potential thereof to a selected potential value, means intermediate said optical train and said charging device for exposing said film member to said pattern only when said potential value is reached, means proximate to said window for applying toner to the film member subsequent to exposure, and means for controlling the applied charge on the film in relation to the incident light intensity.

Claim 51

Apparatus as claimed in claim 31 in which the stepping rate is in the range between about 10 to 30 frames per second so that the projected recorded light pattern appears as continuous motion.

Claim 52

Apparatus as claimed in claim 31 in which said light pattern source comprises a cathode ray tube display unit.

Claim 53

Apparatus as claimed in claim 31 in which means are provided for applying bias to said toner during toning in response to the charge potential sensed at the end of the charging period.

Claim 54

Apparatus as claimed in claim 31 in which said housing and said carrier have means for maintaining said electrophotographic film member in darkness during charging and toning.

Claim 55

Apparatus as claimed in claim 31 in which there is disposed a source of energy sufficient fully to discharge the electrophotographic film, said energy source located along the return path of said film to said housing.

Claim 56

Apparatus for temporarily recording a light pattern on electrophotographic film having a photoconductive coating and projecting said recorded light pattern in a large scale display upon a screen surface, said apparatus comprising: carrier means for holding at least one electrophotographic film member, a housing providing a lighttight enclosure and arranged to receive said electrophotographic film member in a lighttight relationship therewith, said film member having a photoconductive coating, a light pattern source exterior of said housing, projection means exterior of said housing arranged to apply said light pattern to said photoconductive coating, means within the housing proximate to said film member for charging the coating while same is in darkness, means for sensing the absolute potential of the charged coating and simultaneously, for sensing the flux of said light pattern and deriving respective signals from the potential and flux, a control circuit operated by said signals and having a predetermined characteristic which provides an output signal for any level of light flux when the charge potential sensed reaches a chosen value corresponding to any particular flux level and built into said characteristic, means driven by the output signal of the control circuit to disable said charging means and simultaneously to expose said charged coating to said light pattern, means within said enclosure for applying toner to the film member subsequent to exposure thereof, means for adjusting the time of toning and disabling said toner means after a predetermined time interval: said film member being immobilized during the charging, exposure and toning thereof, a projector arrangement, including a light source and an optical train, arranged spaced from said housing for receiving the toned electrophotographic film member and capable of projecting the recorded light pattern upon the screen surface, toner removal means arranged spaced form said projector means and adapted to receive said toned electrophotographic film subsequent to projection for removal of all toner therefrom and means for stepwise translating said carrier means to bring said electrophotographic film member successively to said housing, said projection means, said toner removal means and again to said housing in that order, and said carrier means comprises a disk member arranged for stepwise rotation to deliver said electrophotographic film member along the path intercepted by said housing, said projection means and said toner removal means successively and returning to said housing means.

Claim 57

Apparatus for temporarily recording a light pattern on electrophotographic film having a photoconductive coating and projecting said recorded light pattern in a large scale display upon a screen surface, said apparatus comprising: carrier means for holding at least one electrophotographic film member, a housing providing a lighttight enclosure and arranged to receive said electrophotographic film member in a lighttight relationship therewith, said film member having a photoconductive coating, a light pattern source exterior of said housing, projection means exterior of said housing arranged to apply said light pattern to said photoconductive coating, means within the housing proximate to said film member for charging the coating while same is in darkness, means for sensing the absolute potential of the charged coating and simultaneously, for sensing the flux of said light pattern and deriving respective signals from the potential and flux, a control circuit operated by said signals and having a predetermined characteristic which provides an output signal for any level of light flux when the charge potential sensed reaches a chosen value corresponding to any particular flux level and built into said characteristic, means driven by the output signal of the control circuit to disable said charging means and simultaneously to expose said charged coating to said light pattern, means within said enclosure for applying toner to the film member subsequent to exposure thereof, means for adjusting the time of toning and disabling said toner means after a predetermined time interval: said film member being immobilized during the charging, exposure and toning thereof, a projector arrangement, including a light source and an optical train, arranged spaced from said housing for receiving the toned electrophotographic film member and capable of projecting the recorded light pattern upon the screen surface, toner removal means arranged spaced form said projector means and adapted to receive said toned electrophotographic film subsequent to projection for removal of all toner therefrom and means for stepwise translating said carrier means to bring said electrophotographic film member successively to said housing, said projection means, said toner removal means and again to said housing in that order, and said carrier means comprises a disk member arranged for stepwise rotation to deliver said electrophotographic film member along the path intercepted by said housing, said projection means and said toner removal means successively and returning to said housing means.