Patent application number | Description | Published |
20080204841 | OPTICAL SCANNING DEVICE AND IMAGE FORMING APPARATUS - An optical scanning device includes a deflecting unit, a first sensor, and a modulating system. The deflecting unit deflects a plurality of beams in a main scanning direction to a writing area of a surface to be scanned for scanning the writing area. The first sensor detects a beam to be incident on a point on a first side of the writing area, and outputs a signal in response to detected beam. The modulating system modulates the beams in synchronization with the signal output from the first sensor. | 08-28-2008 |
20080204852 | Optical scanning apparatus, an image formation apparatus, and a phase modulation method - An optical scanning apparatus, an image formation apparatus, and a phase modulation method are disclosed. The optical scanning apparatus includes a liquid crystal device for deflecting an optical beam irradiated by a semiconductor laser. The driving voltages for the liquid crystal device are controlled based on, e.g., the temperature of the liquid crystal device so that degradation of the diameter of a spot of the optical beam due to wavefront aberration is prevented. | 08-28-2008 |
20090074437 | OPTICAL SCANNING DEVICE, IMAGE FORMING APPARATUS, AND WRITE METHOD - An optical scanning device acquires a displacement amount of each of scanning light beams in the main scanning direction, and corrects, based on the displacement amount, writing energy density at a write position such that a variation in image density due to a variation of the displacement amount is reduced. The light beams are used for scanning a target surface to write image data on the target surface. The writing energy density is an amount of light per unit surface area of the target surface. | 03-19-2009 |
20090175657 | OPTICAL SCANNING DEVICE AND IMAGE FORMING APPARATUS - In an optical scanning device, when pixel density is taken to be n, number of the light beams is taken to be b, and number of the deflection surfaces of a deflecting unit is taken to be p, a spatial frequency S denoted by S=1/(1/(25.4/n×b×p) is within a range of a spatial frequency characteristic for a visual perception system of a high relative luminous efficiency. When spacing between ends in a sub-scanning direction of a scanning line formed by one scan by the deflection unit is taken to be L | 07-09-2009 |
20100118366 | POLARIZATION SPLITTING DEVICE, METHOD OF MANUFACTURING POLARIZATION BEAM SPLITTER, OPTICAL SCANNING DEVICE, AND IMAGE FORMING APPARATUS - A polarization splitting device includes a polarization beam splitter having a polarization splitting surface and allows P-polarized light to transmit therethrough and reflects S-polarized light. A subwavelength structure grating is formed on the polarization splitting surface with a grating pitch smaller than wavelength of incident light. The polarization splitting device also includes a polarizer that is arranged on an optical path of light reflected from the polarization beam splitter and has a transmission axis that is parallel to a polarization direction of the S-polarized light. | 05-13-2010 |
20110169906 | OPTICAL SCANNING DEVICE AND IMAGE FORMING APPARATUS - Each light source has plural light emitting portions that are arranged at the different positions in at least a sub-scanning corresponding direction. A memory of a scanning control device stores correction data of the deviation of the beam pitch, correction data of the light amount difference, and correction data to decrease an influence of a reciprocity failure, for each combination of pixel forming light emitting portions. When a write signal is generated, a write control circuit of the scanning control device reads the correction data of the deviation of the beam pitch, the correction data of the light amount difference, and the correction data of the reciprocity failure according to the combination of the pixel forming light emitting portions from the memory, overlaps the read correction data to correction data of an APC, and outputs the overlapped data to a corresponding light source unit as light amount correction data. | 07-14-2011 |
20110316959 | OPTICAL SCANNING DEVICE AND IMAGE FORMING APPARATUS - An optical scanning device, arranged on one side of at least two to-be-scanned members in a second direction, and the two to-be-scanned members being arranged in a first direction perpendicular to the second, includes: an illuminating system that emits beams including a first beam and a second beam whose polarization directions are different from each other; an optical deflector that deflects the beams; and a scanning optical system that includes a polarization separation element that transmits one of the first and second beams and reflects the other; a first mirror group including reflecting mirrors for guiding the first beam to a to-be-scanned member; and a second mirror group including reflecting mirrors for guiding the second beam to a to-be-scanned member. Last-stage reflecting mirrors in the first and second mirror groups are arranged on one side of the beams deflected by the optical deflector in the second direction. | 12-29-2011 |
20120176462 | OPTICAL SCANNING APPARATUS AND IMAGE FORMING APPARATUS - An optical scanning apparatus and an image forming apparatus having the optical scanning apparatus includes a before-light-deflecting-unit optical system and a scanning optical system. The optical system includes a first optical device, a second optical device made of a resin material which has an anamorphic negative refracting power in a deflection scanning direction and a deflection scan perpendicular direction and has a larger refracting power in the deflection scan perpendicular direction than a refracting power in the deflection scanning direction, and a third optical device made of a glass material which has substantially no refracting power in the deflection scanning direction and a positive refracting power in the deflection scan perpendicular direction. An interval of the scanning lines formed on the scanned surface is adjusted by displacement of the second and third optical devices in an optical axis direction of the before-light-deflecting-unit optical system. | 07-12-2012 |
20120189328 | IMAGE FORMING APPARATUS - Apparatus that forms an image according to image information includes density sensors that detect image density variations in main and sub-scanning directions. A processing device generates correction data for correcting a light source output to suppress the density variations based on detection results. The processing device modifies the correction data such that the light source output after the correction is at least a minimum rated output at a position at which the output after the correction is lower than the minimum rated output, in the relation between a position on the surface of the photosensitive element in the main-scanning direction and the output after the correction, and modifies the correction data such that the light source output after the correction is at most a maximum rated output at a position at which the output after the correction is higher than the maximum rated output. | 07-26-2012 |
20130033558 | OPTICAL SCANNING DEVICE, IMAGE FORMING APPARATUS, AND OPTICAL SCANNING DEVICE DESIGNING METHOD - An optical scanning device including a light source having multiple light emitters; an optical element to reflect and transmit the emitted light beams; a photodetector to receive the reflected light beams; an aperture having an opening to shape the transmitted light beams; a light deflector to deflect the transmitted light beams; and a scanning optics to guide the deflected light beams to a scanning surface. The quantity of each of the light beams received by the photodetector is not less than 0.01 mW, and the size of a light receiving surface of the photodetector is determined such that even when the full width at half maximum of the emitted light beams changes, the rate of change of the ratio of the quantity of the light beams detected by the photodetector to the quantity of the light beams passing through the opening of the aperture is not greater than 4%. | 02-07-2013 |