Abstract: An image forming apparatus is provided, with which it is possible to reduce the overall size of an apparatus. The image forming apparatus includes an image bearing member including a plurality of switching elements that are arranged in a moving direction and a generatrix direction of the image bearing member, and a latent image forming unit for forming a latent image on the image bearing member, the latent image forming unit including a voltage generating unit for generating a voltage in each switching element in accordance with an image signal.

Abstract: A recording apparatus for effecting recording on a recording material by recording means, the apparatus includes a tray, mountable to the recording apparatus, for stacking a recording material; a feeding roller for feeding the tray; a portion to be detected, provided on the tray to permit detection of a position of the tray; a tray position detecting portion for detecting the portion to be detected; wherein a position of recording material stacked on the tray is detected by detecting the position of the portion to be detected.

Abstract: A reference or standard pulse number, i.e., a standard number of pulses to be applied to a feeding motor to rotate a feeding roller and thereby feed a recording sheet, is set at Step S21. Subsequently, a feeding amount, A, needed by a recording head is calculated at Step S22, and a feeding amount, B, corresponding to an effective diameter of the feeding roller and the standard pulse number, is calculated at Step S23. Then, a differential pulse number to compensate for the difference between the feeding amounts A, B is determined at Step S24, and a unit error, R, between the feeding amount A and the sum of the feeding amount B (<A) and a feeding amount, C, corresponding to the differential pulse number is determined at Step S26. Subsequently, each time the feeding roller is driven, an accumulated error of the unit errors R is calculated at Step S27, and a number of drive pulses to be applied to the feeding motor is calculated, at Step S34, so that the accumulated error falls in a reference range.

Abstract: Apparatus and methods of printing on an electrically writable medium are disclosed. In one aspect, a printer for printing on an electrically writable medium includes a print head and a biasing system. The print head has multiple solenoid-actuated print wires that are operable to reciprocate toward and away from the medium. The biasing system is coupled to the print head and is operable to apply through print wires extended toward the medium an electric field greater than a threshold electric field needed to reorient switchable display elements in a localized region of the medium.

Abstract: To provide a recording apparatus capable of detecting the deterioration of insulation to prevent the damage of a recording head by detecting whether or not there is the current leakage from a surface of a conveyor belt. The inventive recording apparatus includes a conveyor belt for conveying a recording medium comprising a plurality of inner electro-conductive members, a charging section for charging the inner electro-conductive members by a high voltage to attract the recording medium onto the conveyor belt by an electro-static force, a recording head for carrying out the recording on the recording medium attracted onto the conveyor belt, a leakage detection roller for detecting the deterioration of the insulation of the conveyor belt, and a control section for treating the abnormality in accordance with the results detected by the leakage detection roller.

Abstract: The present invention relates to a recording apparatus which has a positioning means for manual sheet feeding for aligning a sheet feeding position, and a positioning means for auto sheet feeding provided on an auto sheet feeder for aligning the sheet feeding position, and a sheet fed from the auto sheet feeder does not abut against the positioning means for manual sheet feeding, when the auto sheet feeder is attached to the recording apparatus main body.

Abstract: The invention provides an image display medium comprising: a first transparent substrate disposed on an observation side; a second substrate disposed on a further side from the observation side than the first substrate; and a display layer formed between the first substrate and the second substrate and containing a plurality of developer particles; the first substrate including a color filter having at least one group of a plurality of light-transmitting filter films of different colors. The invention also provides an image recording apparatus including a recording head for recording an image on the medium and a positioning device for positioning the filter films of the color filter and the recording head. The invention further provides an image recording method comprising the steps of positioning the filter films of the medium and the recording head, and recording an image by the recording head on the medium having the filter films positioned.

Abstract: A printing unit includes a rotatably mounted transport device for transporting a print carrier sheet in which the transport device is equipped with a holding device for holding a print carrier sheet. The printing unit includes a NIP printing head aligned with the transport device and intended for printing the print carrier sheet. The printing unit is distinguished in that the holding device is mounted to be adjustable into the interior of the transport device.

Abstract: A roll paper curl correction device has a clamp roller for clamping and transporting roll paper, and a guide member comprising a guide face being positioned in the downstream proximity of the clamp roller and formed so that the roll paper is curved to an opposite side of a curl tendency of the roll paper for coming in contact with the non-print side of the paper roll. The guide face can be a curve face formed so as to curve to the opposite side of the curl tendency of the roll paper.

Abstract: Toner and paper powder adhering to and carried by the image non-forming surface of a paper sheet in a developing unit are prevented from fixedly transferring and adhering to the inner wall of the developing unit and the inner wall of the paper sheet introduction port of a fixing unit. As a result, the paper sheet is smoothly carried from the developing unit to the fixing unit while reliably preventing a paper sheet jam. To prevent the adherence of toner and paper powder to the inner walls, first ribs are formed on the bottom surface of the top cover of the developing chamber of the processing unit and second ribs are formed on the paper sheet introduction port side of the top cover of the fixing room of the fixing unit. The first ribs and the second ribs are staggered with respect to one another. In addition, a discharging film is disposed between pairs of adjacent first ribs on the bottom surface of the top cover of the developing chamber.

Abstract: A facsimile machine has a stacker to which printed pages are delivered, and a paper sensor that senses whether the stacker is empty. The facsimile machine clears an internal page count to zero when the stacker is empty, increments the page count as each printed page is delivered, suspends printing when the page count reaches a limit value, and resumes printing when the stacker is emptied. While printing is suspended, facsimile reception may continue in a memory mode.

Abstract: In a process and apparatus for decorating an article, printing ink or electrostatic charges is or are applied in dependence on a digital program in dot form to the article carried by a holder, with individual dots going together to at least form a partial pattern or image. In the case of the latent pattern formed by electrostatic charges, it is then brought into contact with ink particles to form the decoration. In both cases the article is transported along a transportation path through at least one print station provided with an inkjet print head or an ionographic print head, the print head being controllable in dependence on the digital program. The individual nozzles or the electrodes of the respective print head are actuated in accordance with the digital program which is called up for example in dependence on the transportation movement of the article.

Abstract: An image forming apparatus of the present invention continuously conveys a first and a second document set on an ADF (Automatic Document Feeder) and having a reference image size to a document reading unit. When the document reading unit reads the first and second documents, image data read out of the second document are written to a delay memory. After the first document has been read, the image data of the second document are read out of the delay memory on the elapse of a period of time corresponding to a difference between an interval between consecutive papers and an interval between the above documents fed by the ADF. The apparatus can therefore efficiently form the images of two documents at the same time without resorting to a large capacity memory. Alternatively, when the document reading unit starts reading the first document after the second document, the image data of the first document may be delayed by the difference between the two intervals.

Abstract: In the recording apparatus 121, a recording medium fixing member 123 having a plurality of suction ports on the fixed surface to fix the recording medium 101; an adhering roller 143 which can contact with or separate from the recording medium fixing member 123 and which cleans the fixed surface; a flexible plate 137 which is attached onto the fixed surface of the recording medium fixing member 123 and whose contact surface with the recording medium is cleaned by the adhering roller 143; and a suction apparatus for recording medium fixing which sucks the air from the suction ports of the recording medium fixing member 123 and sucks and fixes the flexible plate 137 and the recording medium 101 onto the fixed surface of the recording medium fixing member 123, are provided.

Abstract: An ink jet recording apparatus, which records a image on a recording medium using a recording head provided with a plurality of ink discharge ports, includes a rotative platen having a plurality of supporting pieces arranged at predetermined intervals; a rotation unit for rotating the platen; a conveyance units for conveying the recording medium; a control unit for controlling the rotation unit to rotate the platen in the conveying direction of the recording medium in synchronism with the conveyance of the recording medium when recording is performed near the edge of the recording medium conveyed by the conveyance unit. With the structure thus arranged, this ink jet recording apparatus is capable of performing the entire area recording (no margin recording) on a recording medium without staining the platen that supports the recording medium at the time of recording.

Abstract: In an image forming apparatus comprising a latent image carrier and a writing means having a plurality of writing electrodes which are aligned in the axial direction of the latent image carrier and arranged in contact with or proximity to the latent image carrier to form an electrostatic latent image on the latent image carrier, the contact width of the writing means relative to the latent image carrier is set to be smaller than the contact width of any cleaning means, the width of a toner carrying portion of a developing means confronting the latent image carrier, the width of a transferring means, and the width of a charge removing portion of a charge removing means. In addition, the width of the writing means is set to be smaller than the width of the latent image carrier.

Abstract: A recording sheet is sequentially fed by the transfer roller pairs, first and second feeding roller pairs and a belt conveyor. The feeding speed V1 of the transfer roller pairs including variation is set to be slower than the feeding speed V2 of the feeding roller pairs. The feeding speed V3 of the belt conveyor including variation is set to be faster than that of the feeding roller pairs. When the recording sheet is transferred to the first feeding roller pair from the transfer roller pairs, one-way clutches in the transfer roller pairs are actuated, to race the transfer roller pairs at the feeding speed V2. Before the recording sheet passes the second feeding roller pair completely, the recording sheet is fed at the speed V2 with the leading end portion thereof being slipped on the belt conveyor.

Abstract: A transparent image producing display or receiver which uses a suspension fluid for producing pixels of an image includes at least one image-forming layer having a structure which defines a plurality of pixels, with the structure receiving a suspension fluid having field-driven particles, which move in response to an externally applied field, where, in a first condition, the field-driven particles produce a first level of transmitted incident light and, in an second condition, produce a second level of transmitted incident light.

Abstract: Provided are an image display medium which satisfies a safety and a high-speed response and which is capable of repetitive rewriting, an image-forming method in which an image can be formed on the image display medium, an image-forming apparatus, and an initializer. In the image display medium, conductive particles and insulating particles are interposed between a display substrate and a non-display substrate having a positive charge-transporting property. An electrostatic latent image adapted to the image is formed on an electrostatic latent image carrier. A bias voltage is applied to a counter electrode. Positive charges (non-image portion) on the electrostatic latent image carrier are transferred to the display substrate to charge the conductive particles. The charged conductive particles are moved toward the non-display substrate.

Abstract: Provided are an image display medium which satisfies, a safety and a high-speed response and which is capable of repetitive rewriting, an image-forming method in which an image can be formed on the image display medium, and an image-forming apparatus. An image display medium is formed by interposing black particles and white particles between a display substrate and a non-display substrate made of a dielectric. A printing electrode first applies an AC voltage to frictionally charge the black and white particles, and then applies a DC voltage adapted to an image between the substrates. The black particles adhered to a portion (non-image portion) to which the voltage of the display substrate is applied are moved to the non-display substrate.

Abstract: An image displaying apparatus, a method for displaying an image and an image displaying medium can provide an image of a large viewing angle and high stability of the particles upon repeated use. On electronic paper containing a display substrate formed of a hole transporting film, a non-display substrate formed of a film having a two-layer structure containing a charge transporting film having formed thereon an electrode layer having a thickness of about 50 &mgr;m, and conductive black particles and insulating white particles contained therebetween, an electric field is generated at a position corresponding to image data by a recording head, so as to move the black particles attached to the entire surface of the display substrate toward the non-display substrate, whereby an image of contrast of black and white is formed on the display substrate.

Abstract: The present invention provides pivot 207a of paper edge regulation element 207 that evens up the edges of placed sheets aside from rotation axis 206 of pickup roller 204, forms groove 208 into which rotation axis 206 that has ascended is fitted in paper edge regulation element 207, makes rotation axis 206 fit into groove 208 of paper edge regulation element 207 when pickup roller 204 is lifted to regulate the rotation of paper edge regulation element 207 and makes rotation axis 206 come off groove 208 of paper edge regulation element 207 and become free to rotate when pickup roller 204 is lowered.

Abstract: The present invention provides an image forming apparatus including a sheet supply device having a detachable sheet supply roller for feeding stacked sheets, an image forming device having a process cartridge for forming an image on the sheet fed by the sheet supply device, a cartridge containing portion for detachably containing the process cartridge within a body of the image forming apparatus, and a sheet discharge device for discharging and stacking the sheets on which the images were formed by the image forming device. The sheet supply roller and the process cartridge are disposed adjacent to each other, and, after the process cartridge is disengaged from the cartridge containing portion, the sheet supply roller is mounted and dismounted through the cartridge containing portion.

Abstract: The invention provides a continuous medium printing apparatus which can exert a transporting force to act upon a continuous medium without additional provision of a new tractor mechanism or some other transport mechanism. In the continuous medium printing apparatus, upon automatic loading of a continuous medium, a control section controls a charging operation of a charging section so that a leading end portion of the continuous medium may be electrostatically attracted to an image forming drum. The image forming drum to which the continuous medium is attracted is rotated in a printing transporting direction to exert a transporting force to act upon the continuous medium to transport the continuous medium in the printing transporting direction. The present invention is applicable to an apparatus which prints on a continuous medium such as continuous recording paper (continuous paper), for example, by electrophotography.

Abstract: A recording medium includes a liquid crystal material whose polarizing axis is controlled by an applied electric field, a layer including the liquid crystal material, and spacers for maintaining a constant spacing between the layer, and is formed in the form of a sheet. A visible image is recorded on the recording medium by applying a predetermined electrostatic charge image composed of electrostatic charges on a surface thereof and by controlling the polarizing axis of the liquid crystal material by an electric field formed by the charges of the electrostatic charge image, which controls reflectance or transmittance of incident light.

Abstract: A conventional imagesetting system includes an imagesetter for transferring an image onto media, a wet chemical processor for processing the imaged media, an enclosed dryer section for drying the media by circulating air thereabout, and extraction rollers for extracting the media from the enclosed dryer section.

Abstract: An image forming apparatus which includes a main body which has a printer engine which forms an image on a recording medium, a supply unit which supplies the recording medium to the main body, and a discharge unit which receives the recording medium, on which an image is recorded, discharged from the main body. The supply unit and discharge unit detachably connect to the apparatus and the units are stackable under the main body, and the supply unit and discharge unit have a relaying device for relaying the recording medium which is supplied or discharged from another unit or the main body.

Abstract: The present disclosure is directed to a media tracking guide mechanism for guiding the transport of printing media in a printing apparatus. The media tracking guide mechanism is designed to provide positive tracking to print media of various types passing through the guide as the print media is supplied to a printing apparatus. The print media tracking guide preferably includes a guide housing configured and dimensioned for mounting along a hub portion of a printing apparatus and an armature rotatably coupled to the guide housing. The guide housing includes a core member having a print media transport path along an outer peripheral portion thereof and an overhang support positioned in a spaced relationship from the core member. The overhang support includes a slotted area for receiving a lever component. The core member and overhang support are rigidly coupled to a flange portion along a common side thereof.

Abstract: Apparatus for forming an image, comprising a storage for storing a digitized image and a receiver. The receiver includes a matrix, a thermomeltable material disposed in the matrix having a transition temperature range which is above room temperature wherein the viscosity of the thermomeltable material decreases substantially from below to above the transition temperature range, and field-driven particles immersed in the thermomeltable material, so that the particles change optical densities in response to an applied electric field when the thermomeltable material is above the transition temperature range and is stable at temperatures below the transition temperature range. An array of electrodes selectively applies electric fields at an image forming position on the receiver. The apparatus heats the receiver to control the temperature of the receiver to control the response of the field-driven particles in the receiver.

Abstract: An electrographic imaging element useful for forming colored images is described. The element contains an imaging layer structure and a support structure. The support structure contains an electrically conductive polymeric release layer formed by polymerizing a mixture containing a polymerizable, ethylenically unsaturated ammonium precursor; a polymerizable, ethylenically unsaturated, organo-silicone precursor; a polymerizable precursor containing at least two polymerizable, ethylenically unsaturated functional groups; optionally, a polymerizable, ethylenically unsaturated acidic precursor containing at least one carboxylic acid group; and, optionally, a monofunctional precursor containing one polymerizable, ethylenically unsaturated functional group. The element is particularly useful for forming large size images, such as are required for banners, billboards, and other out-of-doors advertisements.

Abstract: An image forming apparatus is provided which can compatibly realize maintenance of optimum fixing speeds according to fixing characteristics of recording sheets and toner images and a reduction in the size of the apparatus itself as well as an improvement in the productivity of image formation, and which is free of many restrictions such as sizes, transfer speeds, fixing speeds and transfer positions of recording media to be used as well as lengths and fixing positions of transporting units.

Abstract: Disclosed is a method for controlling a temperature of an electric motor. According to the present invention, the method for controlling the temperature of the electric motor includes the steps of setting a present temperature of the electric motor as an initial value, comparing the present temperature with a lower limit temperature when the multifunctional apparatus receives an order to perform a printing, performing the printing if the present temperature is lower than the lower limit temperature at the comparing step, converting a time for printing into an increased value of the temperature at the performing step and resetting the increased value of the temperature as the present temperature, and delaying the printing for a predetermined time if the present temperature is higher than the lower limit temperature at the comparing step.

Abstract: A single pass color printer employs a band drive to move media sheets through plural developer stations. The band drive also provides motive power to drive, in common (via frictional engagement with their respective peripheries), all of the organic photoconductor (OPC) rollers that are present in plural developer stations that are arrayed along the media movement path. The use of the common band drive assures that the surface speeds of the OPC drums and media sheets are synchronized at their respective points of contact, thus eliminating much of the station to station variations due to differences in diameters and runout of the plural OPC rollers.

Abstract: An electro-photographic copying apparatus includes a conveyor system for moving a transferring device between a first position of engaging a conveyor belt against a photosensitive drum and a second position of the conveyor belt being spaced apart from the photosensitive drum. In the first position, an image on the photosensitive drum may be transferred to an image receiving member. In the second position, the copying apparatus is waiting to make a copy. A tension maintaining mechanism may maintain a constant tension on the conveyor belt when the transferring device is in the first or second positions. The copying apparatus may include a discharge system for discharging the conveyor belt when a transfer roller is positioned at the second position. The copying apparatus may also include a cleaning device for cleaning the transfer roller when the transfer roller is positioned at the second position.

Abstract: An image forming apparatus of the type forming a toner image on a photoconductive drum or similar image carrier, transferring it to a paper or similar transfer medium via an intermediate transfer body, e.g., belt, and fixing it on the medium by a fixing device is disclosed. Just after the transfer of a toner image of the last color which is to lie over the other toner images on the intermediate transfer belt, the peripheral speed of the belt is switched to a comparatively low speed matching a fixing and paper transport speed. At this instant, the belt is moved away from the drum. The length of the transfer medium and the distance between a paper transfer position and a fixing position is compared. For a relatively short transfer medium, the peripheral speed of the belt is not switched to the low speed.

Abstract: There is disclosed a second cassette feeding apparatus for an electrostatic image-forming system employed to increase sheet feeding capacity, including a cassette frame for secondary paper feeding, formed on one side of a main body of the electrostatic image-forming system, and having a pickup roller for picking up a sheet of paper, and a driving roller forming a relay roller to convey the paper to a registration roller of the main body; and a second paper cassette inserted into the cassette frame to store sheets of paper, and having a passive roller forming the relay roller with the driving roller.

Abstract: A printing machine composed of: (a) an electrographic imaging member including a substrate layer and a charge accepting layer selected from the group consisting of a silicone elastomer and a grafted elastomer composed of a polyorganosiloxane bonded to a fluoroelastomer; (b) latent image generating apparatus for recording an electrostatic latent image on the imaging member; (c) developer apparatus for depositing marking material on the imaging member to produce a marking material image; (d) a heating device for heating the imaging member so as to form a tackified marking material image thereon; and (e) transfer apparatus for transfering the tackified marking material image from the imaging member to a recording sheet

Abstract: A conducting polymer thin film which comprises a conducting polymer capable of undergoing a physicochemical state change between at least two of an oxidized state, a neutral state, and a reduced state, said conducting polymer in at least one of these states retaining ionic dye molecules incorporated among the molecules thereof. The conducting polymer thin film of the present invention is reduced in power consumption, does not generate any harmful substance, and is capable of being used for continuous image formation. The process for producing the conducting polymer thin film, a method of working the conducting polymer thin film, a method of image formation with the conducting polymer thin film, and an apparatus for image formation are also disclosed.

Abstract: The memory capacity required for temporarily holding image data with respect to a printer is reduced, and loads involved in supplying image data, such as decoding and conversion processes, are dispersed and reduced. The apparatus divides image data in parallel with a main scanning direction by an image divider, stores the divided data in image data memory, and supplies the divided image data to image data temporary memory by an image data supply to perform a decoding process. In order to provide a matching with a process speed, the image data temporary memory temporarily retains the divided image data, and a printer prints an image on a sheet of paper on the basis of the divided image data stored in the image data temporary memory.

Abstract: A method and apparatus for reproducing color images using a non-interactive pyroelectric imaging process is disclosed. More specifically, the present invention is used to generate multiple layers of toner on the top surface of a pyroelectric imaging member without physical contact to the imaging member top surface. The ability to generate a composite image with different materials in this manner enables printing machines to use a pyroelectric imaging process to generate color images in the image on image (I-O-I) mode.

Abstract: A primary charge roller configuration with an annular lip protruding from the roll core prevents wear of the roller edges into the photoconductive drum. The gap between the lip and the shaft created by the lip can be void or can be filled with a soft material, such as EPDM or SBR.

Abstract: A paper handling apparatus has a simplified structure and allows printed paper to be stacked efficiently. The paper handling apparatus receives printed paper which has undergone printing for each print job and handles the printed paper in an orderly manner. The paper handling apparatus has a stacking section in which printed paper is stacked sequentially for a plurality of jobs and an unloading mechanism for unloading stacked printed paper from the stacking section to the outside. The paper handling apparatus can be used with a printing apparatus which is connected to a large-scale information processing system or similar for printing a large volume of data.

Abstract: A double-side digital copier reads an image on documents fed into an image reading unit in accordance with a predetermined cycle based on copying conditions such as the number of copies to be made and single/double-side copying, and the number of documents and copy sheets temporarily maintained in the respective circulation paths formed therein. Further the image data obtained by that reading are stored in two memories alternately, one of the memories alone, or both the memories in a predetermined order in accordance with the predetermined cycle, and are read out in a corresponding order, optimizing throughput without increasing the manufacturing costs.

Abstract: An electrographic imaging element useful for forming colored images is described. The element contains an imaging layer structure and a support structure. The support structure contains an electrically conductive polymeric release layer formed by polymerizing a mixture containing a polymerizable, ethylenically unsaturated ammonium precursor; a polymerizable, ethylenically unsaturated, organo-silicone precursor; a polymerizable precursor containing at least two polymerizable, ethylenically unsaturated functional groups; optionally, a polymerizable, ethylenically unsaturated acidic precursor containing at least one carboxylic acid group; and, optionally, a monofunctional precursor containing one polymerizable, ethylenically unsaturated functional group. The element is particularly useful for forming large size images, such as are required for banners, billboards, and other out-of-doors advertisements.

Abstract: A print control method of an image forming apparatus having a print engine unit which is controlled by a command applied from an external device and prints an image in accordance with image data applied from the external device on a recording medium by a page unit. The method includes the steps of: standing-by a reception of a print command signal from the external device in a stand-by state; detecting an operation state of the external device after starting a print operation in response to the received print command signal; printing an image in accordance with image data on printing paper, discharging the printed paper to outside of the image forming apparatus, and then executing a stand-by mode, when the external device is in a normal state; and stopping a print operation and then performing error processing operation, after discharging printing paper in state of white paper to outside of the image forming apparatus, when the external device is in an abnormal state.

Abstract: A CPU in the main body of the apparatus reads out data for smoothing processing from a ROM in an image cartridge for output to a smoothing circuit. The smoothing circuit performs a prescribed smoothing processing based on the data for smoothing processing and outputs the smoothed image data through an input/output control circuit and a printer engine interface circuit to a printer engine which forms an image. As a result, an optimum image processing suitable for any development characteristic can be performed for an image cartridge which is not compatible with the data for image processing of the main body, and a good quality image can be formed.

Abstract: Rotating drum (10) imagesetter for producing an image on a flexible sheet of radiation-sensitive material, wherein a sheet (20) is held on the inside surface of the drum (14), and the exposure means (25) his located inside the drum.

Abstract: A method for tracking the position of a sheet through a paper path being translated by a plurality of feed mechanisms within a printing machine is provided.

Abstract: In a printing station, pins for engaging edge perforations of the paper are mounted on a toothed belt. The paper is lifted from a position fully engaged on the pins to a tapered head portion of the pins higher up on the pins to avoid stress on the paper from the pins. Lifting of the paper is provided by a paper guide element.

Abstract: The present invention is directed to a precise method of registering a plurality of ROS imagers, so as to form sequential registered images on a photoreceptor belt in a single pass. Pairs of belt holes are formed in the photoreceptor belt, outside the image area and outside of the scan width of the ROS imagers. A pair of light sources are incorporated into the post polygon optics of each ROS imager so as to produce a light spot at the photoreceptor surface which will periodically illuminate the holes on the belt. As the leading edge of the belt holes advances into the beams, detectors placed beneath the belt and beneath the exposure station provide signals representing the exposure level of the light source output. The position of a transmissive optical element with no optical power, subsequent to each of said ROS imagers, is adjusted in response to registration error signals generated by said photodetecting means to adjust the position of said scan lines.