Abstract: A fingerprint image system includes a television camera in a cabinet pivotable between two positions where it views different surfaces on which an image can be placed. In one position it sends a fingerprint image at five times magnification to a printer and a monitor. In the other position it sends the image at actual size to the printer and monitor. A remote, hand-held camera, adapted to view fingerprints directly on surfaces, includes a light shield to prevent ambient light from falling on the fingerprint and light sources, such as a filtered light to cause the fingerprint to fluoresce or colored light to enhance the image.

Abstract: An optical system for an electrophotographic film camera/reader-verifier. The image is transmitted downwardly to a first mirror (28) fixed at an angle of approximately 45.degree. with respect to either a horizontal or vertical plane. The image is, in turn, transmitted to a second mirror (32) fixedly disposed within a vertical plane, and a focusing lens (36) finally transmits the image to a film element for recording thereon. When an image frame of the film element is to be viewed, read, or verified, a projection lamp (40) is energized for illuminating the film element whereby the illuminated image thereof is transmitted to a third mirror (44), which is located at an inclined angle of approximately 15.degree. with respect to a horizontal plane. The mirror (44) in turn transmits the image of the film element to a front projection screen (46) which is also fixedly disposed at an angle of approximately 15.degree. with respect to a vertical plane.

Abstract: A toner flow control system for liquid toner within camera/processor apparatus includes the disposition of a development electrode portion (30, 130, 230) and the electrophotographic film element (14, 114, 214) within planes inclined with respect to a horizontal plane at an angle of between 30.degree. and 60.degree.. A toner flow channel (32, 132, 232) is defined between the development electrode and the film element wherein, as a result of the inclination of the channel, the flow of the liquid toner (36, 136, 236) is able to be controlled and uniformly distributed over the electrode and film element under the influence of gravity.

Abstract: The present invention is a diode bias toning system and method for use in and with electrophotographic copying machines and the like, and provides a significant improvement over "floating" and "hard-wired" toning systems to provide a user with the benefit of self-compensation or self-adjustment sensitometry, while allowing better control of large density percentage images and providing a simple and practical means and method which yield the satisfactory inherent results or advantages of a "hard-wired" system. The employment of a single diode means connected between a development electrode and a variable high-voltage D.C. power supply, so as to prevent the passage of current between the development electrode and the supply means, thereby facilitates the usage of a single high-voltage D.C. power supply to supply both the corona charging and toning biasing functions of an electrophotographic copying machine or system.

Abstract: A toner flow control system for liquid toner within camera/processor apparatus includes the disposition of a development electrode portion (30) and the electrophotographic film (14) within planes inclined with respect to a horizontal plane at an angle of between 30.degree. and 60.degree.. The film (14) and electrode (30) define a toner flow channel (32) therebetween which is also therefore inclined with respect to the horizontal plane at the same angle, whereby the flow of the liquid toner (36) through the channel (32) is able to be controlled and uniformly distributed over the electrode (30) and film (14). In addition, gravity discharge (46) of the toner (36) from the channel (32) is able to be accomplished without the need for special sealing devices to confine the toner within the toner cell. The controlled flow of the toner within the channel (32) eliminates the need for substantial negative pressure or vacuum suction systems normally employed in conjunction with vertically oriented toner channels.

Abstract: A desk-top camera/processor-reader apparatus for electrophotographic film includes a primary optical system of three fixed mirrors (24, 26, 28), and a pivotable mirror assembly (36) for defining optical paths between a copyboard station (12) and the microfilm (30) as well as between the microfilm (30) and a rear-projection screen (18). The pivotable mirror assembly (36) is movable between two extreme positions, the first position (36') being the camera/photographing mode, and the second position (36") being the reader/viewing mode. Camera/photographing and reader-projection lamps (42, 56) are provided for alternative energization and illumination of the copyboard station original documents and the microfilm (30).

Abstract: Apparatus for imaging and developing electrophotographic elements includes a single module (16) within which there is housed three processing stations (18, 20, 22) equidistantly spaced apart at distances corresponding to the distance separating the image frames of an electrophotographic element microformat. The first station (18) charges and exposes a first image frame of the element (12), the second station (20) tones and preliminarily dries the first image frame while a second image frame is located at the first station (18) for charging and exposure, and the third station (22) completes the drying and fuses the first image frame while the second image frame is now toned and partially dried, a new third image frame being presented to the first station (18) for charging and exposure. An intermittent film transport system, not shown, conveys the film element (12) in a unidirectional mode throughout the processing as indicated by the directional arrow (24).

Abstract: Camera for making slide transparencies on electrophotographic film which is carried during processing on one-half of a foldable, planar slide frame. The apparatus includes a reversible drive roll which automatically injects and ejects the frame carrying film for imaging and developing along the processing path of the camera. A corona unit for charging the photoconductive layer of the film is energized during inward movement of the film into the camera. After imaging by a light source, a liquid toner is activated for developing the image during withdrawal of the film along the processing path. The toner head includes spaced doctor blades for removal from the film of excess toner. The camera includes a fan which generates positive air pressure along the processing path during withdrawal of the film. Sensors are provided for processing elements including controlling an electric circuit for sequential operation of the drive roll, corona charging unit, toner pump and fan.

Abstract: An improved slide for electrophotographic film which comprises a pair of slide frame forming panels hingedly connected along adjacent edges enabling the panels to be folded together in superposed relation. The inner surfaces of each panel is coated with a pressure sensitive adhesive which bonds an electrophotographic film to one panel. A transparent protective film or a second photographic film may be bonded to the other panel. A conductive foil strip is affixed along an edge of the film for providing a grounding contact required for imaging the film in a duplicating camera and a release paper is disposed over the adhesive coating of the other panel. Subsequent to imaging, a slide is formed by stripping off the release paper and folding the panels so that the adhesive coating bonds the inner surfaces together with the film being retained therebetween.

Abstract: An improved electrographic recording apparatus and method. An electrographic recording medium has a charge retaining front surface on which charge is distributed in a pattern representing a desired image to be recorded, and a field permeable conductive layer. While charge is being deposited on the charge retaining surface of the electrographic medium, a field is established and maintained behind the rear surface of the medium, said field penetrating the conductive layer and having a field strength on the charged side of the medium that opposes a field that causes charge to be deposited on the charge retaining surface of the medium. In another aspect of this invention, the recording apparatus has a toner application station that is located apart from the charge depositing means, and a second field, having the same polarity as the first field, is established and maintained behind the rear surface of the electrographic medium at the toner station.

Abstract: A development electrode arrangement located in closely-spaced parallel relation to the charge retaining surface of a moving electrographic recording medium. A toner application unit feeds electrostatically charged toner particles into the space between the development electrode arrangement and the charge retaining surface of the recording medium. The development electrode arrangement is comprised of an array of electrode segments each segment being electrically isolated from each other segment and each segment being allowed to float electrically. The floating electrode segments are so arranged that every element of the recording medium that is subjected to the toning process passes over at least one electrode segment during the toning process.

Abstract: Apparatus for imaging electrophotographic film which has a short focal length optical gate for focusing a monochromatic light pattern onto the photoconductive layer of electrostatically charged film. The gate transmits and focuses the imaging light onto the film which is advanced over the surface of the optical gate while being lubricated by an optical liquid having an index of refraction closely matching that of the optical gate. The optical gate and liquid transmit and focus the images on the film at their point of contact. The optical gate may be a cylindrical rod which also may serve in part to define a reservoir for an electrophoretic liquid or toner which blends with the optical liquid adjacent the focal point of the optical gate.

Abstract: An apparatus for transporting a recording medium, such as transparent electrophotographic film, which has a conductive layer, from a supply to a take-up roll. The apparatus includes a drive roller that has a conductive ring. The conductive layer of the film is maintained at a desired potential, generally ground, and a different potential is applied to the conductive ring of the drive roller. When the film contacts the periphery of the drive roller, an electrostatic attractive force is developed between the conductive ring of the drive roller and the conductive layer of the film, thereby allowing the drive roller to transport the film without slip.

Abstract: An improved electrographic recording apparatus and method. An electrographic recording medium has a charge retaining front surface on which charge is distributed in a pattern representing a desired image to be recorded, and a field permeable conductive layer. While charge is being deposited on the charge retaining surface of the electrographic medium, a field is established and maintained behind the rear surface of the medium, said field penetrating the conductive layer and having a field strength on the charged side of the medium that opposes a field that causes charge to be deposited on the charge retaining surface of the medium. In another aspect of this invention, the recording apparatus has a toner application station that is located apart from the charge depositing means, and a second field, having the same polarity as the first field, is established and maintained behind the rear surface of the electrographic medium at the toner station.

Abstract: An improved electrographic recording system. The system includes a first charging corona for providing a distribution of charge on a surface of a recording medium representing a desired image to be recorded on the medium. The system also includes an automatically controlled second charging corona. A sensor continuously monitors the potential of a conductive layer of the medium and automatically controls the magnitude of the charge deposited by the second charging corona so as to maintain a constant potential at the conductive layer of the medium.

Abstract: Disclosed are apparatus and method for electrostatically charging a moving electrophotographic film to a predetermined charge potential over wide variations in film movement speed. The apparatus comprises a corona discharge electrode, high voltage potential means for producing corona current flowing from the corona discharge electrode to the film, an electrically conductive control electrode extending parallel to and across the width of the film at a position less than 1/4 inch from the film and in the direction of film movement from the corona discharge electrode, and biasing means for biasing the control electrode at a potential proportional to the film predetermined charge potential for limiting the charge on the film to the predetermined charge potential.

Abstract: Disclosed is an improved apparatus for electrostatically charging an electrophotographic film held stationary with respect to a corona source. The improvement consists of a capacitor interconnecting the film to ground for limiting the amount of charge deposited upon the film during charging.

Abstract: Disclosed is an improved apparatus for applying a uniform electrostatic charge to a predetermined portion of an electrophotographic film. The apparatus includes a corona generation source and a mask framing the predetermined portion of the film. The improvement consists of an electrically conductive surface surrounding the frame opening of the mask and spaced from the surface of the film and a capacitor interconnecting the electrically conductive surface with ground. The electrically conductive surface on the mask develops a voltage close to that of the surface potential of the film during corona charging so that very little charge field discontinuity exists between the mask and the film, thereby permitting uniform electrostatic charging of the film up to the edges of the portion being charged.

Abstract: Disclosed is an improved copyboard for an electrophotographic recording apparatus which records information from a document onto a film. The apparatus consists of a transparent copyboard upon which the document is placed, light means for illuminating the document placed on the copyboard, mirror means for directing the reflected light image from the document to the film, and lens means for focusing the light image on the film. The improvement to the copyboard consists of a white border extending around the perimeter of the copyboard on the light means side of the copyboard and a dark border extending around the inside perimeter of the white border and on the document side of the copyboard. The copyboard eliminates the undesirable edge toning on an electrophotographic member by photographically reproducing in the border regions of the member a very dark border strip surrounded by a very light border strip.

Abstract: Disclosed is an apparatus for developing an electrostatic latent image on a frame of a multi-frame electrophotograhic film by placement of the film parallel to a closely spaced electrically floating development electrode which has a special size relationship to the charged frame area and by application of electrostatically charged toner particles between the electrode and the film. The development electrode is limited in size to have a potential induced upon it by the charge film which is between the highest and lowest potential charge on the imaged frame. In its peferred use, the development electrode is no greater in size than 10 percent larger than the charged frame area being developed, and preferably does not extend laterally beyond the frame.