摘要:
An IR LED array and method of fabrication having a GaAs wafer with one surface metallized to form a common LED contact. Epitaxially formed on this wafer is a GaAs/GaAlAs heterostructure with successive layers of Ga.sub.1-x Al.sub.x As-n, GaAs-p, and Ga.sub.1-y Al.sub.y As-p on the other surface, followed by an electrical contact layer of GaAs-p+ and an insulating layer of SiO.sub.2, discrete areas of the contact and insulating layers being removed by etching to form viewing windows for the individual LEDs, and with the area of the contact layer bordering the viewing windows being exposed and metallized to provide individual LED electrical contacts. In a second embodiment, the GaAs-p+ layer is dispensed with and the transparent electrically conducting coating is applied directly on both the insulating layer bordering the Ga.sub.1-y Al.sub.y As viewing windows and over the viewing windows. In a third embodiment, an edge emitting LED variant is provided and in a fourth embodiment, various light barrier designs are proposed for preventing optical crosstalk between the individual LEDs.
摘要:
A multi-mode reproduction machine or copier incorporating a full width read/write bar having at least one linear array of LEDs for selectively scanning a document original in a read mode or exposing the copier photoreceptor in a write mode. An array of lens elements is provided for focusing the LED array on both the document original and the photoreceptor, the read/write bar and lens array being combined in a unitary structure selectively movable between read and write positions. In an alternate embodiment the read/write bar and lens array is disposed in a fixed position to permit selective reading of the image developed on the photoreceptor or writing of images onto the photoreceptor.
摘要:
An IR LED array and method of fabrication having a GaAs wafer with one surface metallized to form a common LED contact. Epitaxially formed on this wafer is a GaAs/GaAlAs heterostructure with successive layers of Ga.sub.1-x Al.sub.x As-n, GaAs-p, and Ga.sub.1-y Al.sub.y As-p on the other surface, followed by an electrical contact layer of GaAs-p+ and an insulating layer of SiO.sub.2, discrete areas of the contact and insulating layers being removed by etching to form viewing windows for the individual LEDs, and with the area of the contact layer bordering the viewing windows being exposed and metallized to provide individual LED electrical contacts.In a second embodiment, the GaAs-p+ layer is dispensed with and the transparent electrically conducting coating is applied directly on both the insulating layer bordering the Ga.sub.1-y Al.sub.y As viewing windows and over the viewing windows. In a third embodiment, and edge emitting LED variant is provided and in a fourth embodiment, various light barrier designs are proposed for preventing optical crosstalk between the individual LEDs.
摘要:
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.
摘要:
Method of forming small electro-mechanical modulator chips each with a row of flexible light reflecting fingers which may be butted with other like chips to form a full width electro-mechanical array by forming a silicon dioxide layer on a silicon wafer, forming a conductive layer on the silicon dioxide layer, etching away the conductive layer except for discrete rows of fingers, etching the silicon dioxide layer to create a mask delineating a well below the fingers and line openings in the silicon dioxide at the points where the wafer is to be separated into chips, etching the wafer to open the well and form V-shaped grooves along the openings, cutting a groove in the other side of the wafer along a centerline parallel to, but offset from the centerline of each V-shaped shaped groove by an amount sufficient to allow the wafer (111) crystalline plane to extend from the V-shaped groove to the cut groove, and applying a downward force to the wafer to fracture the wafer along along the (111) plane and separate the wafer into chips.
摘要:
A printer having holographic scanning disc for scanning the imaging beam from a laser diode across a recording member, with a detector for detecting a shift in wavelength of the diode utilizing the zero order beam passing through the holographic scanning disc and a temperature control for controlling diode temperatures, the detector actuating the temperature control to adjust the temperature of the diode when a shift in the wavelength of the zero order beam from a non-mode hop wavelength to another wavelength is detected, adjustment of the diode temperature shifting the beam wavelength back toward the non-mode hop wavelength region.
摘要:
An electrostatic voltmeter with a microdeflector probe having a base, a flexible finger supported on the base in cantilever fashion, the finger deflecting in response to a potential difference thereacross, separate driven and variable capacitance electrodes on the finger sensing the charge voltage on the surface to be measured, the pickup electrode being electrically coupled to the driven electrode, the resulting charge voltage on the driven electrode changing finger deflection and altering the capacitive relationship between the base and the variable capacitance electrode; a predetermined reference voltage on the base; and a circuit for converting the change in capacitance between the base and the variable capacitance electrode to a signal representing the voltage on the surface. In an alternate embodiment, a second microdeflector is provided which changes capacitance between base and variable capacitance electrode in response to noise, and a control for adjusting the signal in response to the noise signal.
摘要:
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.
摘要:
A dual mode reproduction machine or copier incorporating a full width read/write bar having at least one linear array of flexible reflectors selectively bendable in response to the application of electrical potentials thereto, the reflectors reflecting imaging rays either onto an imaging member to expose the same or onto a beam stop in response to an image signal input. A second parallel array of photodetector elements permits a document original to be read line by line, and the document image converted to image signals. Light transmission arrays cooperate with the read/write bar to enable exposure of the imaging member or reading of a document original selectively.
摘要:
A thermal ink jet printhead has a flow directing one-way valve for reducing back-flow directed forces generated by the droplet ejecting ink vapor bubbles, so that most of the bubble generated forces are used to eject ink droplets from the printhead nozzles. The one-way valve is provided by patterning the etch resistant mask to form a flap located at a predetermined position along the ink channels between the heating elements and reservoirs, which is activated by bubble generated forces directed in the opposite direction from the printhead nozzles.