Abstract: A storage device includes a plurality of memory chips and a chip. The plurality of memory chips includes a first memory chip configured to generate a first signal based on a first clock signal, and a second memory chip configured to generate a second signal based on a second clock signal. The chip is configured to receive the first and second signals and generate and output a first and second comparison signal based on a duty cycle of the first and second signals. The first memory chip is further configured to generate a first corrected signal by adjusting a duty cycle of the first clock signal based on the first comparison signal, and the second memory chip is further configured to generate a second corrected signal by adjusting a duty cycle of the second clock signal based on the second comparison signal.

Abstract: An image forming apparatus includes a plurality of image bearers, a plurality of optical writing devices, a plurality of image forming units, and circuitry. The plurality of optical writing devices scan and irradiate the plurality of image bearers with a plurality of light beams according to image data to form latent images on the plurality of image bearers. The plurality of image forming units develop the latent images formed on the plurality of image bearers. The circuitry changes scanning speeds of the plurality of light beams and sets, to each of the plurality of optical writing devices, a correction value of an image misregistration on corresponding one of the plurality of image bearers caused by a change of a scanning speed of corresponding one of the plurality of light beams.

Abstract: An optical writing device, and a method of controlling the optical writing device. The optical writing device and the method includes controlling speed of operation of a light deflector based on image magnifying-power information in a sub-scanning direction parallel to a direction in which a surface of a photoconductor moves, and controlling a prescribed write clock frequency such that a number of clock pulses of write light will become a target number of pulses over a period where the write light scans an area within a prescribed distance in a main scanning direction, the target number of pulses being maintained even when the speed of operation of the light deflector is changed in the controlling the speed of operation of the light deflector. The write clock frequency controller maintains the target number of pulses even when the speed of operation of the light deflector is changed by the light-deflector controller.

Abstract: The technology disclosed uses extreme beam shaping to increase the amount of energy projected through an AOD. First and second expanders and are described that are positioned before and after the AOD. In one implementation, the optical path shapes energy from a source, such as a Gaussian laser spot, deflects it, then reshapes it into a writing spot. In another implementation for image capture, rather than projection system, the disclosed optics reshape a reading spot from an imaged surface to a high-aspect ratio beam at an AOD exit, subject to deflection by the AOD. The optics reshape the radiation relayed by the high-aspect ratio beam through the AOD to a detector. Since light can travel in both directions through an optical system, the details described in terms of projecting a writing spot onto a radiation sensitive surface also apply to metrology sweeping a reading spot over an imaged surface.

Abstract: Embodiments of the disclosure provide for improved print position compensation, for example to improve accuracy of print job(s) performed by a printer. The print position compensation enables an offset of the time until printing occurs on a print media to account for changes and/or erroneous movement in a print media, such as due to slippage and/or other results of a force applied to the print media. Particular embodiments determine data values derived both for an output phase and a retraction phase of the printer's operation. Various embodiments generate a print position compensation based on sensor-based edge position distances determined during each of a media output phase and a media retraction phase. Alternatively or additionally various embodiments generate a print position compensation based on sensor-based media movement phase timestamp differentials determined during each of a media output phase and a media retraction phase.

Abstract: An image forming apparatus includes a light scanning device, a developing portion, a control portion and a storage portion. An evaluation chart includes a first evaluation pattern, a second evaluation pattern, a third evaluation pattern and a fourth evaluation pattern. The first evaluation pattern includes a first dot row and a second dot row, and the third evaluation pattern includes a fifth dot row and a sixth dot row. The fourth evaluation pattern is formed by arranging a plurality of fourth evaluation patches. The fourth evaluation patch includes a seventh dot row and an eighth dot row.

Abstract: An illumination system for producing an illumination pattern for measuring the cornea of an eye and, in particular, for determining the topography thereof and in so doing facilitating distance-independent measurements. The illumination system according to the invention for determining the topography of the cornea of an eye includes an illumination unit and a unit for producing an illumination pattern, wherein the illumination unit includes a plurality of illumination modules. A lens array which produces a spatially distributed, collimated illumination pattern is used as a unit for producing an illumination pattern. The illumination system produces an illumination pattern, by which the topography of the cornea of an eye can be determined. Here, the illumination system is designed as a compact module, and so it can be easily combined with other measurement systems, without colliding with the beam paths thereof.

Abstract: Provided are a three-dimensional printing on-line monitoring method and system, relating to the technical field of three-dimensional printing, so as to solve the technical problem that the existing three-dimensional printing on-line monitoring systems are limited in imaging volume and cannot realize full-longitudinal-depth imaging.

Abstract: An image forming apparatus: includes a developing member to be movable between a development position where the developing member contacts an image bearing member and a separated position where the developing member is separated from the image bearing member; and a control portion controls the number of rotations of a drive portion by causing a light source to emit a light beam when a rotating polygon mirror starts to rotate, and detecting the light beam emitted from the light source by a detecting portion, wherein when the rotating polygon mirror starts to rotate, the light beam does not enter an image region of the image bearing member and the light beam is detected outside the image region of the image bearing member by the detecting portion, in a state of the developing member having moved from the separating position to the development position.

Abstract: A light scanning device includes: a first semiconductor laser 44a that emits a light beam L1; a polygonal mirror 42 that deflects the light beam L1; a reflective mirror 64a that reflects the light beam L1 deflected by the polygonal mirror 42 and causes the light beam L1 to enter a photosensitive drum 13; and a BD sensor 72 that detects the light beam L1 deflected by the polygonal mirror 42. The light scanning device scans the photosensitive drum 13 with the light beam L1 and set scanning timing of the photosensitive drum 13 using the light beam L1 based on detection timing of the light beam L1 using the BD sensor 72. The BD sensor 72 is arranged in the position farther from the polygonal mirror 42 than the last reflective mirror 64a that reflects the light beam L1 immediately before entering the photosensitive drum 13 and arranged inside a scanning angle range ? of the light beam L1 corresponding to an effective scan area of the photosensitive drum 13.

Abstract: An optical scanning device includes a rotary polygon mirror, a plurality of light sources, a light detecting portion, an obtainment processing portion, an a switching processing portion. The rotary polygon mirror has a reflection surface that reflects incident light, and scans, in a scanning cycle, the light reflected on the reflection surface. The light sources emit, toward the reflection surface, a plurality of light beams. The light detecting portion detects a light amount of each light beam reflected on the reflection surface. The obtainment processing portion obtains a switching timing to switch a light emission amount of each of the light sources in the scanning cycle, based on light amounts of the light beams detected by the light detecting portion. The switching processing portion switches the light emission amount of each of the light sources based on the switching timing obtained by the obtainment processing portion.

Abstract: A system for controlling a plurality of laser diodes includes an optical transmitter coupled to the laser diode driver for each laser diode. An optical signal including bi-phase encoded data is provided to each laser diode driver. The optical signal includes current level and pulse duration information at which each of the diodes is to be driven. Upon receiving a trigger signal, the laser diode drivers operate the laser diodes using the current level and pulse duration information to output a laser beam.

Abstract: An image forming apparatus includes a light source, a reflector, a photosensitive member, a light receiver, and an integrated circuit chip. The integrated circuit chip outputs, to the light source, a lighting signal for controlling lighting of the light source. The integrated circuit chip includes a synchronizing signal output circuit, a receiver, a first OR circuit, and a first wiring line. The synchronizing signal output circuit is configured to output a synchronizing signal for lighting the light source. The receiver is configured to receive a first image data signal outputted from an external circuit, the first image data signal being for lighting the light source. The first OR circuit is configured to output a first lighting signal that is a logical sum of the synchronizing signal and the first image data signal. The first wiring line connects the synchronizing signal output circuit with the first OR circuit.

Abstract: An image forming apparatus which makes it possible to grasp such settings of a phase and a main scanning magnification of laser beams as reduce occurrence of moire, by visually checking a plurality of pattern images. Pattern images are formed using a laser beam irradiated from a reference light source and a laser beam irradiated from an adjustment target light source for which each of different phase values is set as a phase setting value. A phase relationship between the phases of the laser beams is adjusted based on the pattern images. Pattern images are formed using a laser beam irradiated from the adjustment target light source for which each of different magnification values is set as a magnification setting value. The magnification of the laser beams is adjusted based on these pattern images.

Abstract: A signal receiving apparatus and method adapted for receiving a MIPI signal are disclosed. The signal receiving apparatus includes a signal receiver, a selector, a decoding apparatus and a byte boundary searcher. The signal receiver receives a clock signal, and obtains an input data stream according to the clock signal. The selector outputs the input data stream to a first or second output terminal according to a decoding error signal. The byte boundary searcher operates a boundary searching operation on the input data stream for generating a byte tuning information, wherein, the signal receiver adjusts the clock according to the byte tuning information for adjusting the input data stream.

Abstract: A light scanning unit and an image forming apparatus employing the same. The light scanning unit deflects light in a main scanning direction, irradiates the light on a photoconductive drum, and includes a beam detecting sensor to detect a horizontal synchronization signal by receiving a part of the light beam reflected and scanned by a beam deflector, and leads of terminals of the beam detecting sensor are not exposed to the light beam to be scanned.

Abstract: In an optical scanning apparatus, a light source includes a plurality of light emitting elements. A light beam output from the source is scanned and deflected by a polygon mirror so as to form an electrostatic latent image on a surface of a light sensitive member. A control unit controls the source so that the source outputs the light beam in a first period before a second period in which the light beam deflected by the mirror forms the image. During the first period for outputting the light beam from the source a period for scanning a non-image region of the member in a state in which the rotation speed of the mirror is being accelerated or decelerated is made longer than a period for scanning the non-image region of the member in a state in which the rotation speed of the mirror is controlled at a constant speed.

Abstract: An image forming apparatus includes a light source which illuminates in response to image data, and a deflector to deflect an optical beam output from the light source into a scanning beam running along a main scanning line across an image forming area in a main scanning direction. There are plurality of beam detectors to detect the scanning beam at a plurality of different positions along the main scanning line, the plurality of beam detectors including first and second beam detectors detecting the scanning beam at positions in front-end and rear-end sides, respectively, in the main scanning direction.

Abstract: An image forming apparatus includes a plurality of photosensitive media, a light source unit which comprises a plurality of light sources, a polygon mirror which deflects a plurality of beams output from the plurality of light sources into the plurality of photosensitive media using a plurality of reflective surfaces, a beam detector which receives beams reflected from the polygon mirror during a rotating process of the polygon mirror, and outputs a beam detection signal, and a horizontal sync signal generator which receives the beam detection signal and counts beam reflecting times during which the beams are reflected from the plurality of reflective surfaces, and compares the plurality of counted beam reflecting times with the compensation values calculated for the reflective surfaces, respectively, generates a horizontal sync signal for a corresponding reflective surface, and provides the horizontal sync signal to the light source unit.

Abstract: An image forming apparatus improved in the accuracy of detecting a time period over which a laser beam is scanned. A laser beam emitted from a laser light source is deflected by a polygon mirror such that the laser beam scans a photosensitive drum. The deflected laser beam is guided onto the photosensitive drum via an imaging lens. A mode hop detection unit detects a mode hop of the laser beam. An image pulse generation section detects a main scanning magnification of an electrostatic latent image formed on the photosensitive drum. When a mode hop is detected, the main scanning magnification in a next scanning cycle is corrected using a correction value stored in a storage unit and used most lately, whereas when no wavelength variation has not detected, the main scanning magnification in the next scanning cycle is corrected using the latest correction value.

Abstract: Drawing control methods, laser irradiating apparatuses, drawing control programs, and recording mediums having recorded therewith are provided that make it possible to efficiently carry out drawing with high quality. The drawing control method controls, by a computer, a drawing device which draws what is to be drawn onto multiple unit regions on a surface of a medium. The computer executes a drawing order determining step which determines a drawing order of a line segment included in the what is to be drawn such that multiple continuing line segments over mutually neighboring multiple unit regions are drawn continuously.

Abstract: A pulse width modulation technique is disclosed for use in an image forming device such as a laser printer or a photocopier. The technique implements a pacer to synthesize the frequency of a serializer circuit by stretching (or shrinking) pixel pulse train data. The pacer stretches the pixel pulse train data in accord with increment data that is based upon information about the image forming device, such as the number of bits in the pixel pulse train data, the number of bits in print engine pulse train, the target print engine frequency, and the serializer frequency. The technique can be implemented with digital circuits that provide digital test data.

Abstract: An optical scanning device that scans a scanning surface in a main scanning direction. The device includes a surface emitting laser as a light source, an optical deflector that deflects a light flux from the light source while rotating around a rotation axis, a monitor light receiving element, a synchronization detection light receiving element, a monitor optical system that directs the monitor light flux to the monitor light receiving element, a synchronization detection optical system that directs the synchronization detection light flux to the synchronization detection light receiving element, and a scanning optical system that directs a scanning light flux to the scanning surface. A combined focal length of the monitor optical system in the main scanning direction is smaller than a combined focal length of the synchronization detection optical system in the main scanning direction.

Abstract: An optical scanning device has a light deflector deflecting a light beam from a light source, a synchronization detection sensor determining timing of starting scanning in main scanning direction based on timing of detecting the light beam scanned in main scanning direction by the light deflector, and a pre-sensor imaging optical system imaging the light beam reflected from the light deflector on the synchronization detection sensor. The pre-sensor imaging optical system moves the imaging position of the light beam on the synchronization detection sensor in a direction making the timing of detecting the light beam earlier or later according to whether variation in temperature causes the magnification of the scanning optical system in main scanning direction to increase or decrease respectively.

Abstract: An optical scanning device has a light deflector deflecting a light beam from a light source, a synchronization detection sensor determining timing of starting scanning in main scanning direction based on timing of detecting the light beam scanned in main scanning direction by the light deflector, and a pre-sensor imaging optical system imaging the light beam reflected from the light deflector on the synchronization detection sensor. The pre-sensor imaging optical system moves the imaging position of the light beam on the synchronization detection sensor in a direction making the timing of detecting the light beam earlier or later according to whether variation in temperature causes the magnification of the scanning optical system in main scanning direction to increase or decrease respectively.

Abstract: The image forming apparatus includes a determination unit configured to determine whether or not a polygon mirror has converged to the number of rotations that allows image formation to be performed, and the determination unit is capable of detecting a first timing and a second timing and determines that the polygon mirror has converged to a number of rotations that allows the image formation to be performed based on an earlier one of the first timing and the second timing.

Abstract: Disclosed are methods, systems, and/or apparatus for the collective marking of a surface by two or more laser beams generated by a laser controller. A method includes receiving one or more input signals from a controller of the laser system. The method also includes adjusting a first mirror through a first galvanometer scanner, a second minor through a second galvanometer scanner, a third mirror through a third galvanometer scanner, and a fourth mirror through a fourth galvanometer scanner based on the one or more input signals. The method further includes steering, through the first mirror and the second mirror, a first laser beam generated by the controller and transmitted to a marking head through a beam delivery vessel; and steering, through the third mirror and the fourth minor, a second laser beam generated by the controller and transmitted to the marking head through another beam delivery vessel.

Abstract: A pixel clock generator device includes a high frequency clock generator, a phase shift data generator to generate phase shift data for controlling a phase shift amount of a pixel clock, a phase shift data pattern generator to read the phase shift data from the phase shift data generator, generate a pattern of the phase shift data for output, and when outputting a same phase shift data pattern for consecutive scan lines, generate, for a next scan line, a phase shift data pattern in which a pixel clock at a position moved by a random number of pixel clocks from a phase-shift position of a pixel clock in a phase shift data pattern for a current scan line is phase-shifted, and a pixel clock generator to generate, on the basis of a high frequency clock, a pixel clock phase-shifted in accordance with the generated phase shift data pattern.

Abstract: An optical scanning device includes a light source that emits a laser beam, a deflector that deflects the emitted laser beam, a scanning lens that causes the deflected laser beam to scan a surface of a photosensitive body at a uniform velocity, a reflector having a reflective surface that reflects the deflected laser beam toward the photosensitive body among the laser beams that have passed through the scanning lens, and a synchronization sensor that receives the laser beam from the reflector and outputs a detection signal. The reflector is set so that a scanning speed in a main scanning direction of the laser beam on a light-receiving surface of the synchronization sensor becomes greater than a value obtained by dividing a scanning distance of the laser beam in the main scanning direction on the light-receiving surface of the synchronization sensor by a response delay time of the synchronization sensor.

Abstract: An optical scanning apparatus, including: a deflector including deflection surfaces and configured to deflect, by the deflection surfaces, light beams respectively emitted from light emitting portions for scanning in a main scanning direction; an imaging optical system configured to guide the light beams deflected for scanning by the deflection surfaces to a surface to be scanned; a light source including the light emitting portions arranged so as to be separated from each other in a sub-scanning direction perpendicular to the main scanning direction and an optical axis direction of the imaging optical system; and a controller configured to control the light source in such a manner that a difference between scanning start timings of the light beams at two adjacent deflection surfaces among the deflection surfaces is different from a difference between scanning start timings of the light beams at other two adjacent deflection surfaces among the deflection surfaces.

Abstract: An image forming apparatus having: a light source for emitting a beam; a deflector for deflecting the beam; a light receiving element for receiving the beam and generating a detection signal; a converter for converting electric potentials of the detection signal into data values and generating time data associated with the data values; and a first calculator for calculating a position of center of the beam from the data values and the time data.

Abstract: Disclosed are a light scanning unit and an electrophotographic image forming apparatus including the light scanning unit. The light scanning unit may include a light source emitting a light beam, a beam deflector that deflects and scans the light beam emitted from the light source in a main scanning direction, a scanning optical system forming an image of a first portion of the light beam that is deflected and scanned by the beam deflector on a scanning surface and a beam detection sensor receiving a second portion of the light beam that is deflected and scanned by the beam deflector for generating a synchronization signal. The beam detection sensor may include a light receiving surface for receiving the second portion of the light beam, and at least two output terminals that are arranged outside an area of the light receiving surface within which the incident second portion of the light beam is confined.

Abstract: An optical scanning device includes a light source, a deflector for deflecting and scanning the beams of light, an imaging optical system, a housing, a synchronization sensor, a circuit board on which the light source and the synchronization sensor are mounted, and an adjustment mechanism. The adjustment mechanism enables an adjustment of an interval between beams of light respectively emitted from the plurality of emission points on a surface to be scanned. The circuit board includes a first part on which the light source is mounted, a second part on which the synchronization sensor is mounted and an intermediate part between the first and second parts. The first part is arranged outside the housing, the second part is arranged inside the housing and the intermediate part passes through a wall surface of the housing. The adjustment mechanism fixes the light source using the housing with the interval adjusted.

Abstract: This image-forming apparatus includes a plurality of photosensitive drums, a plurality of laser scanning units, and a motor control unit. A motor control unit detects the time difference between a change point of the detection signal of a reference color and the change points of colors targeted for phase correction, and, when the absolute value of the time difference is greater than a threshold, carries out a rough adjustment process for reducing the time difference by a drive signal with which a base period has been changed by a first period change amount and thereafter carries out a fine adjustment process for reducing the time difference by a drive signal with which the base period has been changed by a second period change amount smaller than the first period change amount.

Abstract: This invention has as its object to improve an image formation throughput. An image forming apparatus of this invention times a time required until an image formation is ready to start after a reference signal is output, and executes the image formation when the image formation is ready to start (for example, initial processes are complete). Furthermore, when the next reference signal is output during the image formation, the image forming apparatus executes an image formation of the next color after a waiting process based on the timed time.

Abstract: An optical scanning device includes: a light source that emits light rays; an aperture member that adjusts a diameter of the light rays; a deflector including a plurality of reflecting surfaces that deflect the light rays; a scanning optical system that guides a light ray, of the light rays incident on the deflector and deflected by the deflector so as to be subjected to scanning onto a to-be-scanned surface; and a synchronization detector that performs synchronization detection by using a light ray, of the light rays, reflected to the aperture from the deflector is provided.

Abstract: Systems, apparatuses, and methods for pre-rendering image data for a plurality of scanning paths are described here. The method includes receiving image data including a plurality of scan lines for a top portion of an image page, pre-rendering the data for a first scanning path to generate a first data set, pre-rendering the data for a second scanning path to generate a second data set, determining an initial scanning direction, and selecting the first data set or the second data set responsive to said determining. Other embodiments may be described and claimed.

Abstract: Methods and raster output scanner (ROS) systems are presented in which beam delay values are set for an array of ROS light sources based on wiper error and jitter error with column alignment achieved at an alignment location spaced from a center of scan (COS) location toward an end of scan location (EOS) along a fast scan range of operation of the ROS.

Abstract: Provided is a device for detecting a horizontal synchronization signal of an image forming apparatus. The device includes a light intensity converter to convert light intensity of a first beam emitted from a first light source and light intensity of a second beam emitted from a second light source to be different from each other, and outputting the first and second beams; a photo detector to receive the first beam and the second beam output from the light intensity converter, and outputting a first signal having a first level at a time of receiving the first beam and a second level at a time of receiving the second beam; and a horizontal synchronization signal detector to detect a horizontal synchronization signal of the first beam and a horizontal synchronization signal of the second beam by using the first signal.

Abstract: In a beam-spot position compensation method for use in an optical scanning device which scans a surface of a photosensitive medium by a light beam emitted by a light source, a plurality of sections are defined by dividing a scanning region on the scanned surface. An emission timing of the light beam for every section is adjusted so that a spacing between beam-spot positions corresponding to pixels of start and end of each section is changed by a predetermined amount. The sparseness or denseness of beam-spot position spacings of the plurality of sections in the whole scanning region is compensated.

Abstract: An image forming apparatus includes: a plurality of optical systems, each of which includes a light-beam generating unit that generates a light beam, a rotary polygon mirror that deflects the light beam so as to scan a image carrier, and a light-beam detecting unit that detects the light beam deflected for scanning at a predetermined position on a scanning path by rotationally driving the rotary polygon mirror; a time-difference measuring unit that measures a time difference between light-beam detecting signals; a generation-timing determining unit that determines time of generation timing for generating a start signal that designates a start of an image writing operation so that the generation timing does not overlap another timing when each of the light-beam detecting signals is output from the corresponding time-difference measuring unit; and a start-signal generating unit that generates the start signal based on the time for the generation timing.

Abstract: An image forming apparatus that generates a synchronization signal without breaking laser diodes (LDs). The LDs output beams, which in turn are deflected to scan a photosensitive member. The synchronization signal is generated upon detecting the deflected beams. The LDs output the beams so as to generate the synchronization signal, based on which the output timing of the beams from the LDs is controlled. It is possible to select a first mode in which at least two of the LDs output the beams so as to generate the synchronization signal, and a second mode in which one of the LDs output the beams so as to generate the synchronization signal. The value of drive current supplied to at least two of the LDs when the first mode is selected is smaller than the value of drive current supplied to one of the LDs when the second mode is selected.

Abstract: A light source control circuit of an optical writing device, admitting connection of light sources and forming an electrostatic latent image on a photosensitive element by controlling a connected light source, includes: a skew correction unit that corrects a skew of a main scanning line of an electrostatic latent image formed by the light source relative to the photosensitive element; a pattern generating unit that outputs image data for forming a predetermined pattern in an electrostatic latent image; a local deviation correction unit that corrects a local deviation of an electrostatic latent image formed by the light source on the main scanning line by acquiring image data processed to form the pattern and by performing a predetermined process; a light source control unit that causes the light source to emit light based on image data in which the local deviation has been corrected; and a setting value input unit.

Abstract: A light scanning apparatus includes: a light emission unit emitting a first light beam and a second light beam; a motor; a rotary polygon mirror rotated by the motor, forming two scanning lines on a scan object at the same time; an optical sensor detecting the first light beam and the second light beam deflected by the rotary polygon mirror; a deviation measurement unit measuring a deviation amount of starting positions of the two scanning lines on the scan object based on a first detection timing at which the optical sensor detects the first light beam and a second detection timing at which the optical sensor detects the second light beam; and a motor control unit controlling rotation of the motor based on the second detection timing in a measurement non-execution period, and controls rotation of the motor without using the first detection timing in a measurement execution period.

Abstract: According to one embodiment, a laser controller generates a signal which corresponds to an output signal of a laser beam detection sensor before detecting an abnormality, in which the abnormality is detected, in a pseudo manner, on the basis of an output signal of a laser beam detection sensor in which the abnormality is not detected. In addition, the laser controller controls a laser unit which corresponds to the laser beam detection sensor in which the abnormality is detected, according to the generated signal.

Abstract: An image forming apparatus includes an image carrying body, a driving unit which rotates the image carrying body in a medium supplying direction, a light scanning unit which comprises a light source and a beam deflecting unit to scan a light beam from the light source to and fro in a main scanning direction to form a scanning line having an image section and a non image section, and a controller which stops the driving unit if the light beam from the beam deflecting unit is on the image section, and drives the driving unit if the light beam is on the non image section.

Abstract: An optical scanner includes a light source, a scan-deflecting portion including a resonance mirror to scan and deflect along a scan line, a plurality of light receiving sensors for synchronous detection provided on the scan line, a phase controller, an amplitude controller, and an offset controller. The phase controller obtains a difference between a true phase and a target phase, and generates a drive signal incorporating the difference between the true phase and the target phase. The amplitude controller incorporates the difference between a value equivalent of a true amplitude and a value equivalent of a target amplitude into the drive signal generated by the phase controller. The offset controller calculates an offset value by obtaining the difference between each of the time intervals, incorporates the difference between the offset value and a target offset value in the amplitude-controlled drive signal, and supply the drive signal to a driving device.

Abstract: An optical scanning apparatus includes a housing, light source, deflector, imaging lens, reflective mirrors, a synchronization detector and synchronization detection mirror. The housing has a plate to partition the housing. The deflector deflects a light beam emitted from the light source. The imaging lens converts the deflected light beam into a constant speed scanning light beam. The reflective mirrors reflect the constant speed scanning light beam to a photoreceptor. The synchronization detector detects timing for starting scanning of the photoreceptor. The synchronization detection mirror reflects the light beam to the synchronization detector. At least one of the reflective mirrors is disposed midway in a synchronization detection light path extending from the deflector to the synchronization detection mirror. The light beam reflected by the synchronization detection mirror is reflected again by at least one of the reflective mirrors, such that the light beam is guided to the synchronization detector.

Abstract: An optical scanning apparatus includes a reflecting mechanism, a light receiving element and a restricting mechanism. The reflecting mechanism reflects a light beam such that the irradiation point of the light beam moves in a predetermined scanning direction. The light receiving element is arranged in a movement plane defined by the light beam reflected by the reflecting mechanism, and the light receiving element outputs a light reception signal for adjusting the irradiation timing of the light beam in accordance with reception of the light beam reflected by the reflecting mechanism. The restricting mechanism positions the light receiving element relative to the movement plane.

Abstract: A pixel clock generator includes a frequency divider 4 that generates a pixel clock PCLK based on a high frequency clock VCLK, a comparator 5 that calculates an error Lerr in the time obtained by integrating a cycle of the pixel clock PCLK for a target number RefN from a time when synchronization signals SPSYNC and EPSYNC are detected, a filter 6, and a frequency calculating unit 7 that sets a frequency dividing value M of the frequency divider 4. The filter 6 and the frequency calculating unit 7 calculate an average of a frequency of the pixel clock PCLK based on the error Lerr, determine a reference error value from the error Lerr in N-cycles, calculate offset values of the frequencies of N pieces of pixel clocks PCLK based on a difference between the reference error value and the error Lerr, and calculate the frequency dividing value M based on a result obtained by adding the circularly selected offset values and the average of the frequency of the pixel clock PCLK.