Abstract: An image forming apparatus includes: a photoconductor drum; an optical scanner, having a light source, configured to scan the photoconductor drum with light to form a latent image; a developer configured to develop an image, based on the latent image; a cycle detector configured to detect a rotation cycle of the photoconductor drum, to produce a cyclic signal indicative of the rotation cycle; a density detector configured to detect density of the image; a measurer configured to measure the rotation cycle at each rotation, based on the cyclic signal; a generator configured to generate, based on the density, a correcting value for correcting intensity of the light, the correcting value having a correction cycle based on a measurement result of the measurer; and an adjuster configured to adjust the correction cycle based on the rotation cycle measured at each rotation, so that the correction cycle matches the rotation cycle.

Abstract: An image forming apparatus includes: a latent image forming unit that forms a latent image on a latent image bearer with light from a light source; and a correction data generating unit that includes: an acquiring unit that acquires, for each position, a correction value of an intensity of the light source to equalize a density distribution of a latent image; a quantizing unit that generates a correction data for each position by quantizing a correction value for each position; and an excessive correction suppressing unit that outputs the correction data after reducing an amount of change from an immediately preceding latent image formation position, with respect to a position at which an absolute value of a restored value indicating a correction amount and generated based on the correction data exceeds an absolute value of the correction value.

Abstract: An image forming apparatus includes: an image processor configured to perform first image processing on image data having a first resolution and to add tag data to a target pixel where second image processing is to be performed; a resolution converter configured to convert the image data into image data having a second resolution higher than the first resolution, and to perform the second image processing based on arrangement of the image data having the first resolution and the tag data; a pulse generator configured to generate an on-off modulation signal and an application-current switching signal in accordance with the image data having undergone the second image processing; and a light source driver configured to drive the light source in accordance with a current setting value output from an application current setter depending on the application-current switching signal and the on-off modulation signal.

Abstract: An image forming apparatus for forming an image by scanning an image bearer with light modulated in accordance with image information includes a light source configured to emit the light and a control device configured to control the light source in accordance with the image information. The control device sets light emission duration of the light source for forming a particular pixel in the image to be shorter than light emission duration of the light source for forming a normal pixel, which is a pixel other than the particular pixel irk the image, and sets light emission intensity of the light source for forming the particular pixel to be higher than light emission intensity of the light source for forming the normal pixel.

Abstract: An image forming apparatus forms an image by optical scanning. The image forming apparatus includes: a light source; an image processing unit that processes image data; a modulation signal generation unit that generates a light source modulation signal; a light source drive unit that drives the light source based on the light source modulation signal; and a correction value identifying unit that identifies a correction value for correcting a registration error of an image to be formed. The image processing unit performs first image processing of image data with first resolution based on a correction value identified by the correction value identifying unit, the first image processing including deformation processing and gradation processing of the image data. The modulation signal generation unit converts image data processed in the image processing unit into image data with resolution higher than the first resolution and performs second image processing.

Abstract: An image forming apparatus includes a photoconductor drum, a latent-image forming device, a developing device, a density detecting device, and a processing device. The density detecting device is configured to detect densities at a plurality of positions in a main-scanning direction on a developed image. The processing device is configured to acquire at least two light-amount correction tables respectively associated with at least two positions of the plurality of positions in the main-scanning direction on the developed image, the light-amount correction tables being for reducing density variations in a sub-scanning direction at the at least two positions, and correct, for each scan, a set point for setting an amount of light of a light source based on a difference in corresponding correction data between two light-amount correction tables respectively associated with two adjacent positions of the at least two light-amount correction tables.

Abstract: An image forming apparatus includes a drive signal generating unit that generates a drive signal for driving a light source based on a reference pulse signal serving as a reference to form a plurality of pixels arranged in the main-scanning direction of an image, and the drive signal generating unit generates the drive signal by adjusting the pulse width of the reference pulse signal so that the amplitude of portions of the reference pulse signal with the adjusted pulse width corresponding to specific pixels among the pixels is larger than the amplitude of portions corresponding to normal pixels that are pixels other than the specific pixels among the pixels, and so that the pulse width of the portions of the reference pulse signal with the adjusted pulse width corresponding to the specific pixels is smaller than the pulse width of the portions corresponding to the normal pixels.

Abstract: An image forming apparatus includes: a light source; and a light source control unit that supplies a pulse drive current according to image data to the light source. An amplitude of a part of the drive current corresponding to a specified pixel of the image data is larger than an amplitude of a part of the drive current corresponding to a normal pixel of the image data that is a pixel other than the specified pixel and the pulse width of the part of the drive current corresponding to the specified pixel is smaller than the pulse width of the part of the drive current corresponding to the normal pixel.

Abstract: An apparatus includes an image-processing-unit that generates tag information indicating whether each of pixels of a first-resolution image data is a pixel of a character or a line, a resolution-converting-unit that converts the first-resolution image data to image data with a second resolution higher than the first resolution, and a light-source-driving-unit that drives light-source according to the second-resolution image data. The resolution-converting-unit includes an image-matrix-acquiring-unit that acquires an image matrix being image data and tag information with the first resolution in an area containing a target-pixel and pixels around the target-pixel, a pattern-matching-unit that determines whether the target-pixel is a pixel of an edge of a character or a line based on the image matrix, and a first-converting-unit that, when the pixel is the edge pixel, converts the image data to image data with the second resolution of a pattern determined in accordance with a layout of the target-pixel.

Abstract: An image forming apparatus includes: a photoconductor drum; an optical scanning device that drives a light source to scan a surface of the photoconductor drum and form a latent image on the surface; a developing device that develops the latent image; and a density detector to detect density variation of an image in a rotation direction of the photoconductor drum, the image being developed by the developing device. The optical scanning device includes a processing device that is capable of correcting a driving signal for driving the light source on a basis of an output signal of the density detector to adjust at least either one of a correction period and a correction strength of correction data for the driving signal for a rotation period of the photoconductor drum.

Abstract: An image forming apparatus includes: an image processor configured to perform first image processing on image data having a first resolution and to add tag data to a target pixel where second image processing is to be performed; a resolution converter configured to convert the image data into image data having a second resolution higher than the first resolution, and to perform the second image processing based on arrangement of the image data having the first resolution and the tag data; a pulse generator configured to generate an on-off modulation signal and an application-current switching signal in accordance with the image data having undergone the second image processing; and a light source driver configured to drive the light source in accordance with a current setting value output from an application current setter depending on the application-current switching signal and the on-off modulation signal.

Abstract: A light source drive control device includes: an image data generating part that generates line-thinned image data having been subjected to line thinning processing for thinning an edge pixel in image data by a first pixel width; an intensity information generating part that generates intensity information including a first intensity at which a pixel not included in a set second pixel width of an edge in the line-thinned image data is exposed and a second intensity at which a pixel included in the second pixel width is exposed and which is higher than the first intensity; and a light source driving part that drives a light source based on a light source modulation signal generated according to the line-thinned image data and a drive current data switched based on a drive current switching signal generated based on the intensity information.

Abstract: An image forming apparatus includes: a pseudo-halftone processing unit that processes input image data to output image data of first resolution; a resolution converting unit that converts the image data of the first resolution into image data of second resolution that is higher than the first resolution; a modulation-signal generating unit that generates a modulation signal obtained by modulating the image data of the second resolution according to a clock signal; and a light-source driving unit that drives a light source according to the modulation signal. The pseudo-halftone processing unit converts a region of pixels having the same pixel value into a parallel line pattern that is formed with a plurality of parallel lines oblique relative to a direction of arrangement of pixels. The resolution converting unit generates the image data o in which each edge of the lines forming the parallel line pattern is smoothed.

Abstract: An image forming apparatus includes: a latent image forming unit that forms a latent image on a latent image bearer with light from a light source; and a correction data generating unit that includes: an acquiring unit that acquires, for each position, a correction value of an intensity of the light source to equalize a density distribution of a latent image; a quantizing unit that generates a correction data for each position by quantizing a correction value for each position; and an excessive correction suppressing unit that outputs the correction data after reducing an amount of change from an immediately preceding latent image formation position, with respect to a position at which an absolute value of a restored value indicating a correction amount and generated based on the correction data exceeds an absolute value of the correction value.

Abstract: A light source drive circuit for driving a light source is disclosed including a drive current generating unit generating a drive current, the drive current including a predetermined current for obtaining a predetermined light amount from the light source, a first auxiliary current input to the light source prior to input of the predetermined current, and a second auxiliary current added to the predetermined current in synchronization thereto; and a signal generating unit generating a first signal and a second signal, the first signal causing the first auxiliary current to be input for a first period and the second signal causing the second auxiliary current to be applied to the predetermined current for a second period. The first period is shorter than a period from a rise of the predetermined current to when a light amount from the light source reaches the predetermined light amount with the predetermined current.

Abstract: An image forming apparatus forms an image by irradiating light from a light source to an image carrier. The image forming apparatus includes: an image processing unit that processes image data at resolution N; and a control unit that generates modulation data to drive the light source at resolution m×N (m is a positive integer equal to or larger than 2), which is higher than the resolution N, based on the processed image data. Processing at the image processing unit is pseudo-halftone processing to perform line thinning or thickening on a part of the image data. The control unit converts the image data at the resolution N that has been subjected to the pseudo-halftone processing into data at the resolution m×N, and adjusts an amount of light for a part of the image data based on the resolution m×N.

Abstract: An image forming apparatus for forming an image by scanning an image bearer with light modulated in accordance with image information includes a light source configured to emit the light and a control device configured to control the light source in accordance with the image information. The control device sets light emission duration of the light source for forming a particular pixel in the image to be shorter than light emission duration of the light source for forming a normal pixel, which is a pixel other than the particular pixel irk the image, and sets light emission intensity of the light source for forming the particular pixel to be higher than light emission intensity of the light source for forming the normal pixel.

Abstract: An image forming apparatus includes: a pseudo-halftone processing unit that processes input image data to output image data of first resolution; a resolution converting unit that converts the image data of the first resolution into image data of second resolution that is higher than the first resolution; a modulation-signal generating unit that generates a modulation signal obtained by modulating the image data of the second resolution according to a clock signal; and a light-source driving unit that drives a light source according to the modulation signal. The pseudo-halftone processing unit converts a region of pixels having the same pixel value into a parallel line pattern that is formed with a plurality of parallel lines oblique relative to a direction of arrangement of pixels. The resolution converting unit generates the image data o in which each edge of the lines forming the parallel line pattern is smoothed.

Abstract: An apparatus includes an image-processing-unit that generates tag information indicating whether each of pixels of a first-resolution image data is a pixel of a character or a line, a resolution-converting-unit that converts the first-resolution image data to image data with a second resolution higher than the first resolution, and a light-source-driving-unit that drives light-source according to the second-resolution image data. The resolution-converting-unit includes an image-matrix-acquiring-unit that acquires an image matrix being image data and tag information with the first resolution in an area containing a target-pixel and pixels around the target-pixel, a pattern-matching-unit that determines whether the target-pixel is a pixel of an edge of a character or a line based on the image matrix, and a first-converting-unit that, when the pixel is the edge pixel, converts the image data to image data with the second resolution of a pattern determined in accordance with a layout of the target-pixel.

Abstract: An image forming apparatus forms an image by optical scanning. The image forming apparatus includes: a light source; an image processing unit that processes image data; a modulation signal generation unit that generates a light source modulation signal; a light source drive unit that drives the light source based on the light source modulation signal; and a correction value identifying unit that identifies a correction value for correcting a registration error of an image to be formed. The image processing unit performs first image processing of image data with first resolution based on a correction value identified by the correction value identifying unit, the first image processing including deformation processing and gradation processing of the image data. The modulation signal generation unit converts image data processed in the image processing unit into image data with resolution higher than the first resolution and performs second image processing.