Abstract: A thermal dye transfer apparatus includes an array of laser diodes which illuminate a dye carrying donor. The donor absorbs heat from laser light and dye transfers by sublimination from the donor to the receiver to form pixels. Light from each diode laser is modulated to have different pixel density levels.

Abstract: A scanner with high intensity source beam, a modulator for modulating the source beam to provide a zero order beam and first order writing beam in response to an image signal input, a polygon for scanning the writing beam across a moving recording member to write images thereon, a sensor in the path of the zero order beam providing a first black beam intensity signal while scanning between pages and a second white beam intensity signal while the writing beam scans an image background area, a circuit for differencing the first and second beam intensity signals from one another to provide a composite intensity signal representing the intensity of the source beam, and a second circuit for differencing the composite beam intensity signal from an intensity setpoint signal to provide a correction signal for adjusting the rf power to the modulator to maintain a substantially constant writing beam intensity.In a second embodiment, the correction signal is determined by a successive approximation register.

Abstract: A scanning system with unpolarized laser, a birefringent beam splitter to split the unpolarized beam into dual orthogonally polarized beams, a polarization insensitive unitary dual beam modulator for separately modulating the beams in accordance with discrete image signal inputs, and a control for operating the modulator at optimum acoustic power levels.In an alternate embodiment, a quarter wave plate is inserted in the optical path between laser and beam splitter.

Abstract: The stop for the Schlieren imaging optics which are used in an electro-optic line printer to image a multigate light valve onto a photosensitive recording medium has smoothly tapered sides to reduce crosstalk between the pixels of the image. As a result, the transmittance of the imaging aperture, as viewed along the modulation axis of the printer, rolls off relatively gradually and more or less continuously along the edges of the stop, thereby reducing the high angle diffraction off the stop so that the troublesome sidelobes of the coherent amplitude point spread function of the imaging system are suppressed. The stop preferably is in the shape of a parallelogram selected to substantially attenuate either the zero order or the higher order diffraction components of the phase front modulated light beam exiting from the light valve so that the intensity profile of the remaining or unattenuated light has the required image characteristics.

Abstract: A high speed, high resolution raster output scanner having a single source beam; a beam splitter for separating the beam into at least two separate and parallel writing beams; an acousto-optic modulator having a substrate sized to provide a separate modulating channel for each writing beam to pass through without intruding into the other modulating channels; an rf transducer for each writing beam for generating separate acoustic waves in each modulating channel of the substrate; a control circuit for simultaneously intensity modulating the writing beams by the rf output of all transducers in accordance with separate lines of image signals; and optical means for simultaneously projecting the intensity modulated writing beams at points two lines apart on a recording member, the optical means including a polygon for scanning the writing beams across the recording member so as to write plural image lines at once.

Abstract: A raster output scanner having a recording member, a laser, a total internal reflection type modulator having an array of independently addressable electrodes, optical means cooperable with the laser to provide a sheetlike beam of high intensity radiation at the modulator, the array of electrodes being pulsed in succession with each image pixel to provide wave after wave of imaging or non-imaging beams, a scanning polygon for scanning the imaging beams from the modulator across the recording member line by line, and means for pulsing the modulator electrodes at a speed equal to the speed of the scanning polygon and in a direction opposite to the polygon scanning direction to obviate image blur.

Abstract: A xerographic system employing uncharged polarizable toner for developing the latent electrostatic images created on the system photoreceptor, with image exposure means having a laser, optical means for converting the laser beam into a sheet-like line of light for exposing the photoreceptor a line at a time, a total internal reflection type modulator means having an array of independently actuated electrodes in the path of the beam effectively to divide the beam into a line of image pixels in accordance with an image signal input; and for solid image areas, plural adjoining electrodes being actuated concurrently to provide simultaneously side by side beams which destructively interfere with one another and create nulls between adjoining pixels thereby enhancing development of solid image areas by said uncharged toner.

Abstract: An acousto-optic modulator for a high speed/high resolution raster output scanner, the modulator have a substrate composed of substantially pure gallium phosphide, with a relatively thin high frequency transducer comprised of a piezo electric layer sandwiched between metal electrodes and employing a conformable adhesive to prevent distortion of the crystal or transducer.

Abstract: A micro-deflector comprised of one or more flexible reflector fingers athwart the path of a beam of high intensity light in a raster scanner, the fingers deflecting on the application of a bending potential thereto to guide the light impinging thereagainst along a different path, together with means to speed up restoration of the fingers to an undeflected quiescent position following removal of the bending potential through the application of a dampening potential to the fingers as the fingers approach the undeflected position.

Abstract: A raster output scanner in which a twisted nematic liquid crystal is disposed in the path of the linearly polarized scanning beam incident on the scanner modulator to provide controlled rotation of the plane of polarization of the beam to maximize modulator diffraction efficiency and beam intensity, control over the crystal external electric field being either exercised manually or automatically, the latter through a feedback loop using a photodetector to monitor changes in beam intensity at the scanner photoreceptor. In an alternate embodiment, the liquid crystal is replaced by a magneto-optic cell.

Abstract: An electro-optic printer of the type having a laser, a modulator for modulating the laser beam in accordance with image signals; an optical system including a rotating polygon for sweeping the modulated beam across the photosensitive drum of a xerographic system to expose the drum and create images thereon, the modulator having a plurality of separately controlled electrode groups effective to modulate portions of the laser beam in accordance with individual lines of image signals to enable multiple image lines to be exposed at once on the photosensitive drum; and a step drive to synchronously step the photosensitive drum in increments equal to the combined width of the lines being processed.In a first alternate embodiment, the modulator is based on a wave guide, and in a second alternate embodiment, the modulator is composed of a series of flexible reflective fingers.