Abstract: An illumination control system for electrographic apparatus of the type utilizing a reusable photoconductive insulator member that changes in electro-photosensitive properties during the period of its useful life. The system includes a device for sensing and storing usage information about such member, for providing signals representative of cumulative usage of the member and for increasing the exposure of the member in accordance with a non-linear schedule which corresponds to photochemical, sensitometric changes that occur in the member with increasing cumulative usage.

Abstract: Electrophoretic migration imaging apparatus and method of the type using electrophotosensitive pigment particles are improved, e.g., as to image density and background, by providing an enlarged migration environment for the imaged electrode. In one embodiment the non-imaged electrode and pigment dispersion thereon are moved predeterminedly, in direction and rate, so as to supplant non-imaged electrode surface and dispersion presented to imaged electrode portions during each successive imaging sequence.

Abstract: Improved migration imaging techniques and apparatus utilizing a mixture of multicolor electrophotosensitive particles are achieved by exposure of the mixture, between electrodes which create a migration-inducing field, sequentially to the color separation components of the original image to be reproduced. Certain disclosed embodiments utilize exposure at spatially separated color sub-zones within an overall imaging zone to effect migration in controlled sequence, by particle type.

Abstract: A light control device comprises a plurality of minute particles, having dipolar and light control characteristics, which are supported in an elastic solid matrix. The particles have a length to width ratio greater than two and are supported in a common orientation across the elastomeric matrix to block (or transmit) incident light. Under application of an electric field across the layer the particles reorient to provide a reverse light control effect. Upon removal of the field the particles quickly return to their original orientation. Image display embodiments utilizing a photoconductor or other imagewise field providing structures are disclosed.

Abstract: A mist of substantially-neutrally-charged, colorant-activating particles is deposited on a receiver in accordance with its interaction with an imagewise modulated ion stream. The deposited particle image is contacted with developer material to form a high density image.

Abstract: Apparatus for heat processing sheet or web material includes a rotary drum and guide web of low friction coefficient and idler rollers which cooperate with the moving drum to effect feed of the material through the processing path.

Abstract: Electrophotographic apparatus in which changes are effected in operative substations to compensate for variation in machine performance during the transition period between a rest condition and a steady state run condition. In one embodiment a decrease in exposure directly proportional to run time and increase in exposure directly proportional to rest time are effected by resistance capacitance circuits.

Abstract: A device for applying single component developer includes an electrically conductive fur brush which charges the toner triboelectrically and which serves as a donor roller to a touchdown applicator roller. Electrical metering means control the supply of toner to the applicator and to the image member to be developed to facilitate more uniform image development.

Abstract: An improved display device utilizes an electro-optical panel including an electrically insulating layer and a light-modulating layer of dipole, light control particles dispersed in a transparent matrix. An imaging electric charge pattern is impressed on the panel to establish a particle orienting field thereacross. The light modulating pattern thus created in the modulating layer is selectively changed between positive and negative image sense by selective application and removal of a uniform field of the same polarity as, but lesser magnitude than, the imaging charge pattern. The stored image pattern is erasable by application of a reverse polarity field. Preconditioning the panel with a uniform field facilitates a positive light modulating pattern in the first instance.

Abstract: Apparatus for automatically tracking an endless belt or web of material in a stable, predetermined path of movement despite changes in the belt configuration due to differential belt stretching or the introduction into the machine of a new belt having a slightly different configuration. The apparatus includes a steering roller supported for rotational movement about the longitudinal central axis and tilting movement about an axis perpendicular to the longitudinal axis. In one embodiment, a steering roller control signal is produced by comparing the magnitude of the weighted sum of voltage signals representative of the lateral belt edge position and the tilted roller position with the magnitude of the integrated sum of the lateral belt edge position signal and a command signal representative of the desired lateral belt edge position.

Abstract: A compact viewer having an active display belt supported for movement around an endless loop and a projection station for scan-exposing successive image portions, from the image medium to be viewed, onto successive portions of the belt where they are temporarily stored for viewing. In a preferred embodiment images are selectively scan exposable at opposite sides of the viewing station to facilitate bidirectional image retrieval. An erasure station is provided along the belt path at a location spaced from the viewing station to prepare the belt for display of new images.

Abstract: Method and apparatus for linearizing the response of a mirror galvanometer or the like to a reference driving signal. An optical assembly transmits through a transmission grating a scanned light beam deflected from a reference signal driven galvanometer mirror. The beam passing through the grating is modulated thereby and received by a photocell. The transmission grating modulates the scanned beam in accordance with the velocity of scan of the light beam and the photocell produces an output signal having a freqency content corresponding to the velocity of the beam. An electrical circuit, in response to the frequency content of the photocell output signal, produces a control signal which is combined with the reference driving signal and applied to the galvanometer to deflect the galvanometer mirror in a manner linearly related to the reference driving signal.

Abstract: An electrophotographic apparatus having improved structure and procedures for regenerating electrophotosensitive properties of its photoconductive imaging member. Erase lights, of spectral quality matching peak absorption characteristics of the imaging member, are located to enable their radiation to be strongly absorbed proximate the positively biased surface of the imaging member. The regenerative sources are provided at locations around the copying path which cause relief of field load on the photoconductor during each cycle, soon after its useful function has been accomplished.

Abstract: An apparatus and method are disclosed by which a processed photosensitive material can be provided with a lenticular surface with each lenticule having a predetermined profile. The lenticules are arranged relative to one another with such a degree of accuracy that any speckle and scintillation that might be produced when the processed material is utilized as an element of a transmission or reflection type screen is reduced to a minimum, if not completely eliminated. Once the exposure factors for the emulsion have been established, the exposure profile can be determined for a particular lenticule profile to be imaged onto the photographic material or emulsion. The exposure profile can be utilized to provide a transparency master target pattern which can be of a relatively large size.

Abstract: The disclosure relates to a control apparatus for the preparation of silver halide emulsions in which the flow rates of the reactants can be controlled to provide a desired pAg in the precipitation vessel. Several embodiments are used, depending upon the desired accuracy of pAg. The pAg and flow rate can also be caused to follow programs to maintain constant, or to vary, the pAg during a particular emulsion making process.

Abstract: A centrifugal molding method is provided for making a plastic lens having a gradient index of refraction. A reusable silicone rubber mold is placed in a rotatable mold carrier and two copolymerizable monomer compositions containing monomers having different indices of refraction are combined in the mold to form a polymerization mixture which has an index of refraction varying radially outward from its axis of rotation. The first monomer composition is placed in the mold and, while the mold is rotating sufficiently to force the first monomer composition to the outside edge of the mold, a second monomer composition is introduced via hypodermic injection into the center of the mold. The speed of rotation is reduced and the two monomer compositions diffuse one into the other in a controllable manner.

Abstract: An electrographic apparatus, of the type employing a brush-type developer applicator which contacts one side of a flexible electrostatic image-bearing web, has (1) a web feed-path constructed in a predetermined configuration and (2) the applicator predeterminedly positioned relative to the feed-path defining elements, such that the flexible image-bearing web is allowed to move freely toward and away from the developer applicator in response to the varying contours of the applicator.

Abstract: Lenticules of predetermined optical power and size are formed photographically in the emulsion of a photographic film. An emulsion is exposed to a target having a profile mathematically related to the cross sections desired in the lenticules to be formed. Exposure can be to a cyclically uniform target through a cylindrical lens, by scanning the cyclical target across the emulsion, or by scanning a single profile across the film emulsion in a raster pattern. Upon processing the emulsion in a prescribed manner, a phase image comprising contiguous cylindrical lenticules having cross sections which are predetermined in accordance with the target profile is formed in the emulsion. In a second embodiment, lenticules in an array or matrix having predetermined profiles are produced by exposing two emulsions to a target as above described and processing both emulsions to density images. The density image carrying processed emulsions are then superimposed, the density images formed thereon being orthogonally oriented.

Abstract: A device for the processing of uniquely combined thermally developable, photosensitive layers with illuminating means for imagewise exposing one of the photosensitive layers while it is being heated to development temperature and also exposing with another illuminating means another of the photosensitive layers from the image exposed and developed in the first photosensitive layer, the last exposed layer being developed by the same heating imparted thereto for development of the first exposed layer to obtain an image which can be transferred in the same operation to a receiving medium.

Abstract: Devices for redistributing incident radiation in a prescribed manner. Such devices comprise a multitude of contiguous optical microelements, each of such microelements being contoured and oriented to redistribute incident radiation, emanating from an intended irradiating source, only throughout an angular field just large enough to encompass a predefined region wherein the redistributed radiation has particular utility. Moreover, the contour and orientation of each microelement is such as to produce substantially uniform radiance throughout such predefined region of utility, and to redirect extraneous or undesirable radiation incident thereon away from said predefined region. The radiation-redistributive devices of the invention are particularly useful as front or rear projection screens, lighting reflectors or refractors, illumination aids for photographic prints, traffic signs, advertisements, etc.