Abstract: A print head has driver circuitry that dynamically drives a row of driven elements, such as light-emitting elements, by driving different combinations of first and second terminals. The print head includes memory circuits storing compensation data for the driven elements, and multiplexing circuits that select the compensation data according to the combination of terminals being driven, thereby enabling the compensation data to be stored in the print head despite the use of dynamic driving. The compensation data are used in adjusting the amount of energy supplied to the driven elements. The amount of compensation data to be stored may be reduced by sharing the upper bits of the compensation data among a group of driven elements.

Abstract: A discharge device usable in an electrostatographic printing machine uses a plurality of emissions to discharge an image receiver, such as a photoreceptor, of the printing machine. The discharge device can be used as a charge erase device, a reconditioning device, an imaging device, or a combination of these. In embodiments, the different emissions come from different groups of emitters within the device, such as from rows of emitters or from groups interspersed within a single row. In other embodiments, at least some of the emitters are tunable and can emit more than one type of emissions. For example, tunable LEDs could be employed in the device.

Abstract: An exposure apparatus performs exposure of a photosensitive body by an array of light emitting devices to form an image as a latent image thereon. The array of light emitting devices incorporate micro-optical cavities. The micro-optical cavities limit wavelengths of light emitted from the array of light emitting devices, so that the wavelength at a peak of emitted light is in a half width region of sensitivity versus wavelength of the photosensitive body.

Abstract: Semiconductor print engine structures (304) are formed by growing high quality epitaxial layers (26) of monocrystalline materials overlying monocrystalline substrates (22) such as large silicon wafers by forming a compliant substrate for growing the monocrystalline layers. The compliant substrate includes an accommodating buffer layer (24) including a layer of monocrystalline oxide spaced apart from a silicon wafer (22) by an amorphous interface layer (28) of silicon oxide. The amorphous interface layer (28) dissipates strain and permits the growth of a high quality monocrystalline oxide accommodating buffer layer (24).

Abstract: The invention pertains to a drying apparatus within a sheet-fed printing machine, in particular, a sheet-fed offset printing machine, with a device for acting upon the moving sheets with air and/or heat. The present invention is based on the objective of expanding a drying apparatus of this type in such a way that the drying effect is improved. According to the invention, this is achieved due to the fact that the apparatus contains an electrode (E) and a corresponding counter-electrode, wherein the electrode is connected to a high-voltage source (HV) and a high voltage is applied to the electrode by the high-voltage source in dependence on the operation of the sheet-fed printing machine and/or the length of the sheets (B).

Abstract: An image forming apparatus and an image forming method for preventing reducing of density of an image transferred to the recording paper due to dropping in a temperature, without providing a temperature sensor. The current detecting unit detects an electric current value generated at the time a test voltage is applied to a transferring member which is provided for transferring a developed image on a photoconductive drum to the paper. The detected current value is input and stored by a printer controller. The printer controller determines an exposure time, based on the stored current value, by reference to a table for determining an exposure time. The printer controller causes the exposure time to be long when the stored current value is small or large.

Abstract: A circuit and method are provided for generating light to illuminate a subject such as a print medium for scanning using, for example, a contact image sensor. The circuit includes a light emitting diode and a variable current control circuit coupled to the light emitting diode. The variable current control circuit is configured to establish a current through the light emitting diode, the magnitude of the current being variable. The variable current control circuit includes a programmable current sink. Alternatively, the variable current control circuit may also include an offset current sink. The programmable current sink and the offset current sink (if included) are employed to establish the variable current through the light emitting diode.

Abstract: Distortion of an LED array head is eliminated by correcting an electrode pitch misalignment between an LED array substrate and a driver substrate to be caused by thermal expansion or contraction during thermal pressure bonding of a flexible cable. A tear preventing hole is formed in each area between adjacent four-divided areas of the flexible cable. When positions of the flexible cable and driver substrate are to be aligned, a pitch shift adjusting slit line is cut in order to correct the position misalignment to be caused by thermal expansion or contraction generated when the flexible cable is thermal-pressure bonded to the LED substrate. The pitch shift adjusting slit line is formed in the connection area between adjacent four-divided areas.

Abstract: A compact light weight printhead capable of direct quasi-contact printing includes an OLED structure deposited onto a substrate. The printhead is designed for contact or quasi-contact printing, without additional optical elements. The printhead design ensures that the desired pixel sharpness and reduced crosstalk is achieved. Two possible different arrangements for the printhead are disclosed. One arrangement includes at least one array of OLED elements. Each OLED array in this arrangement includes at least one triplet of OLED elements, and each element in each the triplet is capable of emitting radiation in a distinct wavelength range different from the distinct wavelength range of the other two color filters in the same triplet. In the second arrangement, the printhead includes at least one triplet of arrays of individually addressable Organic Light Emitting Diode (OLED), elements.

Abstract: A method of manufacturing a printer with an EL pixel array as a latent image light source, comprising: forming an EL pixel array on a substrate; separating the EL pixel array from the substrate; affixing the separated EL pixel array to substantially completely surround the outside of a photoconductive drum; forming a charge generating layer above the EL pixel array; and forming a charge transfer layer above the charge generating layer.

Abstract: An LED array head includes a circuit board and a plurality of LED array chips mounted thereon. Each of the plurality of LED array chips has a plurality of light-emitting elements aligned and exposed on a surface thereof. The plurality of LED array chips are aligned on the circuit board in a direction in which the plurality of light-emitting elements are aligned, so that the plurality of light-emitting elements lie on a single straight line. The LED array chips are bonded to the circuit board by an epoxy resin type soft adhesive.

Abstract: A light emitting array unit for emitting line-shaped light is provided. A first light emitting element array includes a first group of plural light emitting elements, for emitting a first train of spotted lights. A second light emitting element array is disposed to extend substantially in parallel with the first light emitting element array, and includes a second group of plural light emitting elements arranged alternately with the plural light emitting elements in the first group, for emitting a second train of spotted lights. A first prism element group receives incidence of the first spotted light train, and emits the first spotted light train in a predetermined direction. A second prism element group receives incidence of the second spotted light train, and emits the second spotted light train in the predetermined direction. The line-shaped light is constituted by the first and second spotted light trains and is emitted.

Abstract: An image forming apparatus for forming an image on a recording material includes a photosensitive member, an array of light emitting elements for exposing the photosensitive member in accordance with an image information, and a developer for developing pixels exposed by the ray of light emitting elements, wherein the array of light emitting elements further emit a light during a time period other than a time period during which the array of light emitting elements emits a light in accordance with the image information.

Abstract: A method for setting the amount of light in an array of light-emitting thyristors, each thyristor having I-L characteristic in which a luminous efficiency is decreased in a lower current field, is provided. According to the method, the amount of light emitted from a light-emitting thyristor is set so that a predetermined exposure energy may be obtained without decreasing a luminous efficiency of a light-emitting thyristor. The density D of a current to be supplied to the light-emitting thyristor to obtain a predetermined exposure energy is selected so as to satisfy the range of 3×Dth<D<100 MA/m2, wherein Dth is a threshold current density for light emission which is defined as a current density corresponding to the value of a current at a point where a tangent drawn at the value of a current corresponding to a current density of 50 MA/m2 with respect to the curve of the I-L characteristic intersects a current axis.

Abstract: An image forming device comprises a print head in which an array pitch of organic EL elements arranged in a main-scanning direction is at least twice the size of a light-emitting portion of one organic EL element, an aperture diameter of a microlens is no more than the array pitch, and the aperture diameter has an area that is larger than that of the light-emitting portion of the organic EL element. After the exposure of a photosensitive material onto the emitted light from the organic EL element, the photosensitive material is moved for each movement by moving the print head in the main-scanning direction by a predetermined amount to fill a space between exposure spots at which mutually adjacent organic EL elements are focused, and divide exposure of one main-scanning line of the photosensitive material into a plurality of exposures without leaving any space.

Abstract: Imaging offset problems in imaging systems, such as electrophotographic (EPG) printers and copiers, are overcome. Imaging offset results from misaligned exposure units that, when uncompensated, produce dots on a photoreceptor belt at exposure positions that are offset from ideal dot positions. An imaging-offset compensating method of the invention first determines the imaging offset, which is a distance that may include a magnitude and a direction. The imaging offset is determined with respect to the ideal dot position. A time factor is then determined based on the magnitude of the imaging offset for each exposure unit. The time at which each exposure unit is actuated is modified by a respective time factor so that a dot produced by each exposure unit matches the ideal dot location thereof.

Abstract: A LED monolithic array type like emitting device which has a plurality of light emitting parts. The device is particularly suitable as a light source for printers. Each light emitting part has a light emitting diode having a laminate structure. The laminate structure has an end-type GaAs substrate and, epitaxially grown on the n-type substrate in the following order: 1) an n-type GaSa buffer layer, an n-type laminated reflection film formed of layer pairs, each having AlGaAs layers different from each other in aluminum composition ratio, an n-type AlGaAs lower cladding layer, a p-type or undoped AlGaAs active layer, a p-type AlGaAs upper cladding layer and a p-type AlGaAs contact layer. Each layer pair making up the laminated reflection film has an AlX1GA1−X1As layer and an AlX2GA1−X2As layer where X1 and X2 represent the Al composition ratio.

Abstract: A compact light weight printhead capable of direct quasi-contact printing includes an OLED—Color Filter structure disposed on a fiber optic faceplate substrate. The OLED—Color Filter structure includes an OLED structure emitting over a broad range of wavelengths and color filter arrays that selectively transmit radiation in different distinct ranges of wavelengths. The printhead is designed for contact or quasi-contact printing printing. The printhead design ensures that the desired pixel sharpness and reduced crosstalk is achieved. Two possible different arrangements for the printhead are disclosed. One arrangement includes at least one array of OLED elements and at least one color filter array. Each color filter array in this arrangement includes at least one triplet of color filters, and each element in each the triplet is capable of transmitting radiation in a distinct wavelength range different from the distinct wavelength range of the other two color filters in the same triplet.

Abstract: The image reproduction system includes a light exposure unit and a photosensitive member having an outer surface. The exposure unit includes a staggered plurality of linear LED arrays and a staggered plurality of discrete objectives associated therewith which focus the light generated by the LED arrays on the outer surface of the photosensitive member.

Abstract: Primary scanning or other operation is not required by the light source of an internal exposure method, significantly improving the positioning of each color. An EL pixel array 134 is affixed as internal light source 124 to the entire surface of a photoconductive drum 114, and pixels controllable by TFT layer 144 are allocated to the entire image formation area of the photoconductive drum 114. Unlike with a conventional internal light source using an LED, a mechanism for moving in a primary scanning direction is therefore not needed and elements whereby the position of each color image shift are completely eliminated. As a result, there is absolutely no color shifting in full color images, and high quality images can be obtained.

Abstract: An LED printer head capable of reducing influence of a sub emission band by use of a rod lens array and thus prevent light of the sub emission band from reaching a development level. The LED printer head consists of an LED array of LEDs to emit light according to an image signal, which are arrayed at the resolution pitch P of not less than 600 dpi, and a multi-lens array for forming an emission image of the LED array on a photosensitive body. Each of the LEDs of the LED array has a main emission band of an emission spectrum and another sub emission band having a peak level of not less than 0.01 as a photosensitive intensity ratio R to the main emission spectrum, and a difference D between best total conjugate lengths at peak wavelengths of the main and sub emission bands by the multi-lens array is at least 0.15.

Abstract: Disclosed is a method for measuring light quantities emitted from an array of light shutter elements aligned in a main scan direction. The method measures the light quantities by scanning and sensing a recording paper on which an image is formed by the light shutter elements. The scan direction is orthogonal to a direction in the image corresponding to the main scan direction of the array.

Abstract: A rod lens array for optical printer head includes a plurality of rod lenses arranged cyclically in a predetermined direction. The rod lenses are fixed by filling a opaque substance into the gaps separating the respective rod lenses and sandwiching the rod lenses and the opaque substance with a pair of side panels. The side panels have a cyclical structure resulting in undulations at least on their surface facing the rod lenses, and the pitch of the beat generated by the cycle or arrangement of the plurality of rod lenses and the cyclical structure of the side panels is not greater that 0.6 mm or substantially infinite.

Abstract: An optical writing device includes light-emitting element array substrates, connecting members, self-focusing rod-shaped lens arrays, and a package case. Each of the light-emitting element array substrates includes light-emitting elements arranged in a line for emitting light in a straight line. The light-emitting element array substrates are placed in parallel and partly in an overlapping formation to be able to write on an area of a predetermined width in a direction in which the plurality of light-emitting elements of each of the light-emitting element array substrates are arranged in the line. Each connecting members connects two adjacent light-emitting element array substrates to each other around a position, at which an operation for writing dots with the light-emitting elements, is switched from one of the light-emitting element array substrates to a subsequent one of the light-emitting element array substrates.

Abstract: The image reproduction system includes a light exposure unit and a photosensitive member having an outer surface. The exposure unit includes a staggered plurality of linear LED arrays and a staggered plurality of discrete objectives associated therewith which focus the light generated by the LED arrays on the outer surface of the photosensitive member.

Abstract: An optical writing device includes an integral structure of a plurality of light emission device array units securely connected together, the units including respective lines of light emission devices, the lines being formed into a longer line of light emission devices on the integral structure, a position fixing member, and a connection mechanism that fixes the integral unit to the position fixing member only at a single connection point such that displacement of the integral unit relative to the position fixing member in a direction of the longer line is prevented only at the single connection point but unrestricted at any other points.

Abstract: A print head has an array of surface-emitting light-emitting diodes formed in a chip, near one edge of the chip. The chip is mounted on a conductive pattern on the component surface of a printed circuit board. The printed circuit board includes a material, exposed on the component surface throughout a region adjacent to the above-mentioned edge of the chip, that is less optically reflective than the conductive pattern. Emitted light that leaks through the chip edge is partly or completely absorbed by the exposed material, instead of being reflected by the conductive pattern. The exposed material may be a dielectric coating, a dielectric substrate, or a conductive paste that also bonds the chip to the conductive pattern.

Abstract: An image forming apparatus is provided for producing an array of dots in the primary scanning direction based on image data prepared for one line. The apparatus includes enlarging means for enlarging the image data n times in the primary scanning direction to form images with a resolution equal to (1/n) times a maximum resolution, where the n is a positive integer. The image forming apparatus also includes dot forming means for forming dots for n lines in the secondary scanning direction based on the enlarged image data.

Abstract: An exposure device in which an image forming lens is disposed in such a posture that the center line of an image forming is out of axial alignment with the center of beam intensity distribution of the light emitting diode output (the center of beam intensity distribution) so as to reduce possible incidence of stray light when local part of the light output from the light emitting diode array reflects on said wires. As a result, the stray light does not strikes the circumference surface of the image supporting body and the vivid image can be formed.

Abstract: An electrophotography apparatus is provided with one or a plurality of recording units which optically form a latent image on a body. Each of the recording units includes a plurality of light emitting elements having a shape which satisfies a relationship t/y<T/Y<1, where t indicates a width of a pixel of the latent image in a sub scanning direction, y indicates a length of the pixel in a main scanning direction, T indicates a width of a light emitting element in the sub scanning direction, and Y indicates a length of the light emitting element in the main scanning direction.

Abstract: A xerographic printer includes a rotatable photoreceptor which is exposed, with each cycle, by a regular exposure device to create an image desired to be printed. Elsewhere along the photoreceptor is disposed a supplemental discharge device which discharges only those small areas on the photoreceptor which were not discharged by the regular exposure device within the cycle. In this way, every small area of the photoreceptor is evenly discharged within each cycle, and thus every small area of the photoreceptor experiences the same amount of aging. The system is particularly useful for full-color xerographic printers, in which the photoreceptor is repeatedly discharged by different exposure devices within each cycle.

Abstract: An electrophotographic image forming apparatus including an LED (Light Emitting Diode) array head and a method of generating data for correcting the quantities of light to issue form the LEDs of the LED array head are disclosed. Only the quantity of light that actually contributes to development is uniformed throughout the LEDs. This reduces the scatter of a dot area in a latent image and thereby enhances image quality while insuring the sufficient resolution of the LEDs.

Abstract: An image forming apparatus is provided for producing an array of dots in the primary scanning direction based on image data prepared for one line. The apparatus includes enlarging means for enlarging the image data n times in the primary scanning direction to form images with a resolution equal to (1/n) times a maximum resolution, where the n is a positive integer. The image forming apparatus also includes dot forming means for forming dots for n lines in the secondary scanning direction based on the enlarged image data.

Abstract: Bit data of a received video signal is partially converted into a first signal representing a data sequence corresponding to the resolution of an LED head. The first signal is transmitted to the LED head in the form of a real printing data signal that is to be printed on a basic raster line in synchronism with a line timing signal. The remaining bit data of the received video signal, which are not converted into the first signal, are converted into a second signal representing another data sequence, and then stored in a line buffer. The second signal stored in the line buffer is transmitted to the LED head in the form of a real printing data signal that is to be printed on an additional raster line in synchronism with an additional line timing signal. The LED head drive energy with which the basic raster lines are printed and another LED head drive energy with which the additional raster lines are printed are set independently of each other. The LED head may be provided with such a resolution function.

Abstract: An object is to provide an LED printer head in structure capable of reducing influence of a sub emission band by use of a rode lens array and thus prevent light of the sub emission band from reaching a development level, thereby achieving high quality to the contrary. The LED printer head consists of an LED array of LEDs to emit light according to an image signal, which are arrayed at the resolution pitch P of not less than 600 dpi, and a multi-lens array for forming an emission image of the LED array on a photosensitive body. Each of the LEDs of the LED array has a main emission band of an emission spectrum and another sub emission band having a peak level of not less than 0.01 as a photosensitive intensity ratio R to the main emission spectrum, and a difference D between best TCs at peak wavelengths of the main and sub emission bands by the multi-lens array is at least 0.15.

Abstract: Compensation data for use in driving an array of printing elements in a printing head are obtained by measuring the uncompensated output value of each printing element, calculating a target value for each printing element, and determining a compensation value from the difference between the measured output value and the target value. The target values vary continuously across the array. The compensation data are stored in a non-volatile memory in the printing head. During printing, each printing element is driven with an energy corresponding to the compensation data, so that the output profile of the array follows the profile of target values.

Abstract: In a light-emitting diode array panel in which an array of light-emitting diode pellets having a light-emitting region are arranged substantially in a straight line on a long and narrow substrate made of resin along the length thereof and on one side of the width center thereof, the substrate is kept warped when the light-emitting diode pellets are arranged on the substrate. Alternatively, the light-emitting diode pellets are arranged in a curved line. This ensures that the array of light-emitting diode pellets forms a straight line after a heat-hardening process.

Abstract: An image forming apparatus includes a photosensitive member, an exposure device includes a single-chip light emission element array formed by integrating a plurality of light emitting elements in a single chip which exposure device executes the exposure in the main scanning direction relative to the movement of the photosensitive member, by the light emission from the single-chip light emission element array, and a developing device provided around the photosensitive member.

Abstract: The present invention provides an exposure device capable of operating at a high speed and obtaining an excellent printing result. The exposure device according to the present invention includes optical write heads using shift registers of two systems, and a circuit that supplies image data for one line divided into the first half and the second half to the respective shift registers. The circuit is consist of a write control section, a memory, a read control section and a transfer control section), and receives data of twice the number of bits of data inputted to the shift register.

Abstract: An electrophotography apparatus has a charging unit, and an exposing unit, and a developing unit. The charging unit charges the surface of a rotating image bearing body having an axis of rotation. The exposing unit emits light to illuminate the surface of the image bearing body to form an electrostatic latent image on the surface. The developing unit applies charged toner to the electrostatic latent image to develop the electrostatic latent image into a visible image. The electrophotography apparatus includes, for example two electrodes and power supplies for applying voltages to the electrodes. The electrodes are disposed between the light-emitting surface of the exposing unit and extend parallel to the axis of rotation of the image bearing body. The electrodes are aligned on opposite sides of the light emitted from the exposing unit.

Abstract: A light emitting diode based exposure station (and electrophotographic marking machines that use such exposure stations) that requires only a small amount of photoreceptor waterfront (space). The small waterfront requirement is achieved using a gradient index lens array that transmits focused light onto the photoreceptor with a total conjugate that is sufficient to permit the widest part of the light emitting diode based exposure station to be displaced sufficiently far from the photoreceptor that other printing machine devices can be disposed between the widest part of the exposure station and the photoreceptor. The increased total conjugate is achieved using a gradient index lens array having longer rods and/or wider rods.

Abstract: A light-emitting device includes: a first plate provided a conductor pattern thereon; a second plate, a plurality of light-emitting elements disposed at predetermined portions on the first plate, respectively; a plurality of light-passing structures provided so as to respectively correspond to the plurality of light-emitting elements, wherein the light-emitting elements are sealed with a transparent resin sealant.

Abstract: An image forming apparatus includes: a plurality of light-emitting elements, each light-emitting element receiving a driving current from a power supply and converting the current into a beam; a plurality of driving elements, each driving element being interposed between the power supply and each light-emitting element and controlling the driving current based on an image signal; and a photoconductor on which the beams from the plurality of light-emitting elements form an image by scanning, wherein each light-emitting element is positioned so immediately adjacent to each driving element that a power leakage factor floating therebetween is reduced, whereby an intensity of the beam is substantially equivalent to the image signal in waveform.

Abstract: Regardless of a relative installation position error between a light source and a photosensitive material, or of a deviation from a properly preset value of rotation speed of a photosensitive material, images are obtained with minimum loss of image quality and excellent reproducibility. The number m of light-emitting elements to make up a unit and the distance between adjacent pixels formed on the photosensitive surface are adjusted such that the width of the pixel groups is ⅓ mm or less, which is a period that the periodic image noise is not recognized as stripes.

Abstract: Arrays of light emitting diodes, and LED printbars and electrophotographic marking machines that use arrays of light emitting diode, that have active area geometries that produce compact irradiance profiles. Compact irradiance profiles are achieved by placing the diode electrodes along the outer periphery of the light emitting active areas. When used with gradient index lenses, such light emitting diodes produce light spots having more compact irradiance profiles. When such light emitting diodes and gradient index lenses are incorporated into LED printbars, and when those printbars are used in expose stations of electrophotographic marking machines, improved composite images can result.

Abstract: An optical write head operable in high speeds is provided with better printing results. The optical write head is arranged by an LED array constructed of a plurality of LEDs arrayed in a line form, one shift register used to store thereinto pixel data for a front half portion of this LED array, and the other shift register used to store thereinto pixel data for a rear half portion of this LED array. The optical write head is further arranged by registers for latching parallel pixel data outputted from these shift registers, and a driving circuit for simultaneously driving the LEDs employed in the LED array in response to patterns of the pixel data outputted from the registers when a control signal is inputted.

Abstract: A circuit board holds a line of light emitting elements mounted thereon. The light emitting elements are at a predetermined height from the surface of the circuit board. A rod lens array longitudinally extends and forms images of the light emitting elements on a photoconductive body such that the images and the light emitting elements form pairs of conjugate points with respect to the rod lens array. A holder holds the rod lens array relative to the light emitting elements. Supporting members are mounted to the holder at locations along a length of the rod lens array and hold the rod lens array relative to the circuit board so that the images form a substantially straight line on the photoconductive body. Each of supporting member supports a part of the rod lens array relative to the circuit board.

Abstract: In an image forming apparatus for electrophotographically forming an image with an LED (Light Emitting Diode) array having a number of LEDs arranged in an array for controllably emitting light in accordance with image data, dots to be respectively formed by the LEDs have a target dot diameter X satisfying a relation of P<X<2P where P is a pitch P between the LEDs. Despite that the dot diameters of LEDs may slightly differ from each other, an image free from noticeable white stripes or black stripes is achievable although some difference in density may occur, depending on the overlapping degree of or the distance between dots.

Abstract: A character generator for a printer or copier which illuminates a surface of a photoconductor is provided with a cooling device, wherein a line of LEDs is mounted on a bearing surface of a hollow, thin walled profile that runs along the direction of the LED row. The hollow interior is filled with a liquid. On the other side of the hollow profile from the row of LEDs is a heat dissipating structure, such as a finned heat sink.

Abstract: When an image is scanned and recorded on a photosensitive material, the quantity of emitted light of each of light emitting elements is corrected by controlling, based on digital image data, quantities of light beams emitted from light emitting portions of three colors, which each consist of a plurality of light emitting elements. A drive signal level of each of the light emitting elements is corrected for the same digital image data so that the light emitting elements which emit light beams of the same color have the same quantities of emitted light. Subsequently, the drive signal level of each of the light emitting elements is corrected for predetermined digital image data so that the ratio of the quantity of emitted light between the light emitting elements, which emit light beams of different colors, is set at a predetermined value.