Abstract: A phototypesetter is disclosed having a stepping motor which actuates an escapement carriage coupled to an elongated carriage driving member. A projection lens carriage and a collimating lens carriage are selectively electromagnetically coupled to the elongated driving member, thereby to project images of varying character sizes through a focusing lens coupled to the escapement carriage, which sequentially projects focused character images across a photosensitive film on a line by line basis. A track select mirror is also selectively electromagnetically coupled to the elongated driving member for selectively projecting one of a plurality of tracks bearing characters of differing fonts carried by a rotatable font carrier element.

Abstract: A lithographic printing plate is produced by the steps of forming a latent electrostatic image on a photoconductive zinc oxide insulating layer and developing this layer with a toner which forms an imagewise deposit on the recording layer. Applicants' invention relates to contacting the portions of the recording layer which are not covered with the hydrophobic deposit with a hydrophilizing composition (commonly called a conversion wash) comprising the reaction product of (1) phosphoric acid or one of the anions derived from such acid, (2) an organic amine compound, and (3) a hydrophilic metal cation, to form a reaction product with zinc ions from the zinc oxide which reaction product of zinc ions with said composition is substantially insoluble in said composition and is preferentially wetted by water thereby repelling lithographic inks. The plate produced by this process is especially useful for use on a lithographic offset press to produce multiple copies of an original.

Abstract: An electronically tunable optical filter is described wherein an optical beam is diffracted by an acoustic beam the group velocity of which is noncollinear with the optical beam transmitted through the birefringent crystal medium. The frequency and the direction of the phase velocity of the acoustic wave are chosen for a given incidence direction of the optical beam so that the diffraction occurs for a band of optical frequencies centered about a predetermined optical frequency and a relatively large angular distribution of incident optical beams.

Abstract: A two-part replaceable cassette-like device is provided, having a disposable cassette portion and a light sealed buffer box, having a pair of drive rollers therein and which is detachably fastened to the disposable cassette, whereby the photosensitive material driven out of the cassette will be driven through the light sealed buffer box into a camera processor. Upon exhaustion of the photosensitive media within the cassette, the buffer box is removed from the cassette for reuse and the cassette is thrown away. A gear coupled to the buffer box roller material drive means is automatically rotated during insertion and withdrawal of the buffer box to and from the camera due to roller contact with a stationary drive gear positioned within such camera.

Abstract: For variable letter sizes being photographically recorded in a second generation phototypesetter, it is desired to increase generated quantities of light flux produced by the flash lamp operating in conjunction with a font disc where larger letter sizes are thereby imaged upon the photosensitive medium, and conversely, to reduce such flux where smaller characters are to be projected. The disclosed system employs a digital letter size code for controlling the amount of charge inserted into a storage capacitor via a digital to analog converter and multivibrator. When the flash lamp is triggered at the appropriate time to selectively illuminate a given character, the energy associated with the stored charge is employed to energize the lamp.

Abstract: A solar energy collector of low cost and high thermal efficiency is disclosed having a heat trap produced by zigzagging a thin strip of polyethylene terephthalate between opposite sides of the trap while wrapping the strip about rows of dowels positioned at opposite sides of the frame of the solar collector. A window of soda lime glass filters UV radiation to inhibit discoloration of the plastic heat trap walls. An absorber plate having fluid pipes therein is positioned underneath the heat trap and a first layer of fiberglass, and a second layer of polyurethane foam are positioned below the absorber plate. The fiberglass layer prevents overheating of the polyurethane foam layer to in turn inhibit the formation of toxic fluids, which may condense upon the underside of the window to reduce the efficiency of the collector.

Abstract: Film transport apparatus for phototypesetters. The apparatus includes upper and lower guide plates supporting pinch and drive rollers, respectively, between which a strip of film is frictionally fed. A pair of hold-down rollers are provided to press the upper guide plate against the lower guide plate to maintain the pinch and drive rollers properly positioned against each other, and also to help keep the apparatus locked together during operation. The upper guide plate is designed to be laterally slidable relative to the lower guide and further is provided with a pair of notches cut into its sides. Accordingly, to load film into the apparatus, it is only necessary to slide the upper guide plate until the hold-down rollers become aligned with the notches at which position the upper guide plate can be lifted up and away from the lower guide plate to separate the pinch and drive rollers for film loading.

Abstract: An automatic freeze protection system for solar energy collector apparatus. The apparatus includes a solar collector for circulating water or another fluid to be heated by the sun. Sensor means are provided within the collector to monitor the temperature of the water, and whenever it approaches the freezing point, the sensor will automatically actuate a valve means to rapidly drain the water from the collector. When the temperature within the collector thereafter rises to a predetermined safe level, the sensor means will again automatically actuate the valve means to refill the collector with fresh water to be heated. The system provided thus avoids the need for anti-freeze or other freeze protection materials suggested by the prior art as well as isolated water loops, heat exchangers and other expensive safety equipment necessitated thereby.

Abstract: A roller is coupled to a movable support frame which in a first position bears a flexible halftone screen which is fully wound up about said roller. As the support frame is translated in a first direction across the film mounted upon a vacuum platen, the flexible screen unwinds and is laid flat across the platen. When the movable support frame is translated in a second direction, the screen is thereafter wound up about said roller somewhat in the manner of a "reverse windowshade.

Abstract: A hydrophilic copolymer of an N,N-di(C.sub.1 -C.sub.2 alkyl)acrylamide is disclosed. The copolymer is formed by reacting, based on 100 parts, from about 20-80 parts of a C.sub.1 -C.sub.2 alkyl substituted acrylamide, about 10-80 parts of a C.sub.1 -C.sub.4 alkyl acrylate, methacrylate, or combinations of acrylate and methacrylate, and about 2-20 parts of a glycidyl ester of acrylic, methacrylic or crotonic acid. The resulting copolymerization product can be equilibrated with water or other aqueous solutions to form hydrogels useful in forming shaped hydrogel articles. One particular shaped article which can be formed is a hydrophilic contact lens. A process for forming the hydrogels is also disclosed.

Abstract: A system for adding or subtracting in real-time image detail of first and second images. In a first embodiment a plane parallel reflective image shear plate superimposes a first radiation beam carrying the first image with a second radiation beam carrying the second image to achieve exact registration of similar image detail. Depending upon the phase difference between the first and second beams, the beams either destructively or constructively interfere. Constructive interference results in amplitude addition of image detail in the first and second images. Destructive interference results in an image having only image detail which is different between the first and second images. A second embodiment adds a plane parallel source shear plate to the structure of the first embodiment, which results in several significant advantages. In the second embodiment radiation from a light source is first directed against the source shear plate which shears the radiation to derive the first and second radiation beams.

Abstract: An optical sensor is positioned at the output of a variable magnification optical system which focuses differing character size images upon a photosensitive medium. A reference voltage, which is a function of the proper exposure for a particular photosensitive medium, is compared with the photosensor voltage. The system automatically tests for the correct light flux before each size change by projecting a reference image through the optical system at the photosensor, such image having a relatively low intensity level, so that no output signal is produced by the above-mentioned comparator. The intensity of the reference image is iteratively increased until such output signal is produced by the comparator, thereby to maintain the light intensity at the last level attained, until a character size change is effected, wherein the comparison process is repeated.

Abstract: A camera-processor magazine is disclosed having a cartridge for storing light sensitive roll material, together with means for driving such material out of the cartridge and upon an exposure platen. A roller curtain for shielding the material when the magazine is open also functions to guide the leading portion of the roll material across the exposure platen and into the nip of a pair of exit rollers.

Abstract: A pivotable camera back is provided containing a film cartridge having a movable light sealing member for preventing light from entering the cartridge when the camera back housing is pivoted to an open position for access thereto, together with a sealing member actuation device for causing the light sealing member to open with respect to the cartridge feed orifice to permit photosensitive material to be fed to the imaging area upon the closing of the camera back housing.

Abstract: Method is disclosed for transferring non-fused xerographic toner images from a first support material, such as a photoconductive insulating surface, to a second support material, such as paper, and fusing the toner images to the second support material. Such method utilizes an intermediate transfer member having a smooth surface of low surface free energy and a hardness of from 3 to 70 durometers. The intermediate transfer member can be, for example, a 0.1-10 mil layer of silicone rubber coated onto a polyimide support. The member can be formed into belt or drum configuration. Toner images are transferred from the first support material to the intermediate transfer member; this can be by any conventional transfer method, but pressure transfer is preferred. Next, the toner image is heated on the intermediate transfer member to at least its melting point temperature.

Abstract: A first and second channel coupled to a leading edge comparator and a trailing edge comparator is provided wherein pulses having widths to be determined are transmitted to the comparators, the pulses in one channel emanating therefrom being delayed with respect to pulses emanating from the other channel. Biasing circuitry produces an offset bias voltage to change the relative D.C. levels of the pulses, thereby to establish two leading edge crossover points which effect operation of the leading edge comparator and two trailing edge crossover points which effect operation of the trailing edge comparator so that the time differences between pulses produced by the comparators is a measure of the widths of the pulses, regardless of changes in pulse amplitude, D.C. input drift, and changes in duty cycle.

Abstract: A circularly polarized, broad-beamed antenna system capable of effectively covering the entire bandwidth of from about 0.5 GHz to about 18 GHz or higher. The system provided comprises a generally conventional planar spiral antenna modified by having the outer ends of its arms terminated by a bifilar helix. The bifilar helix is positioned behind the planar spiral and at 90.degree. to it. By proper coupling of the two antenna portions, it has been found that within the 2 to 18 GHz range, the planar spiral operates as if the helix were not present, while below 2 GHz, the spiral functions as a transmission line feeding the helix and the helix radiates essentially all of the energy from the antenna.The antenna system provided is approximately the same size as conventional 2 to 18 GHz cavity backed spiral antennas and generally satisfies all of the physical constraints and limitations placed upon airborne radar-warning systems.

Abstract: A novel development system for controlling the flow rate of developer through a narrow development zone, using a reservoir which has a feed chamber for maintaining a constant pressure head at the entrance to the narrow development zone. Developer flow is initiated upon demand by virtue of actuation of a valve positioned between the feed chamber and the entrance to the development zone; since considerable developer mixing occurs in the developer reservoir, mixing devices for mixing added toner with carrier beads may be simplified.

Abstract: A process is disclosed for applying an adherent, optically clear, abrasion resistant coating to polycarbonate substrates such as lenses. The process includes: (a) forming a coating solution containing 25-75% of a hydrolyzed C.sub.1 -C.sub.2 alkyltri(lower alkoxy)silane, such as methyltriethoxysilane, in a water-miscible, volatile, organic solvent, and also containing small amounts of an abrasion-resistance enhancer and a stabilizing weak acid; (b) applying a thin, uniform coating of the coating solution to a clean surface of the polycarbonate substrate; and, (c) dehydrating the coated substrate under low humidity conditions at an elevated temperature below the temperature at which the substrate degrades until an adherent, abrasion resistant coating is formed.

Abstract: A toner dispensing apparatus for electrophotographic copiers. The apparatus includes a toner dispenser portion positioned within the developer housing of the copier, and a toner supply portion positioned exteriorly of the developer housing. The two portions are detachably secured to one another such that when the supply of toner in the toner supply portion becomes exhausted, that portion may be replaced in its entirety. Both portions are provided with a novel valve means to permit transfer of toner from the supply portion to the dispenser portion in normal operation and to prevent toner spillage from either portion when separated. Additionally, a novel toner agitator structure is provided in the toner supply portion to ensure a smooth flow of toner therefrom. This structure includes a plastic bag for holding the supply of toner together with means for periodically deflecting the walls of the bag to loosen up the toner therein.