Abstract: An optical scanning apparatus includes M number of light sources that includes M number of semiconductor lasers and M number of coupling lenses, where M is a positive integer, a deflecting scanning unit that deflects laser beams from the light sources to a surface to be scanned, and a transmission-type prism that deflects optical path of the laser beam from at least one of the light sources by an infinitesimal amount of angle. The prism is disposed between the light sources and the deflecting scanning unit, has an incident surface and an output surface nonparallel to each other, and can rotate around an axis of rotation substantially parallel to the optical path of the laser beam.

Abstract: A scanning imaging optical component is used in an optical scanning device which deflects a beam from a light source by a light deflector, condenses the deflected beam toward a surface to be scanned by a scanning imaging optical system, forms a beam spot on the surface to be scanned, and performs optical scanning of the surface to be scanned. The optical component forms at least a part of the scanning imaging optical system, and at least a part of a surface of the optical component other than an effective optical surface is made to be a roughened surface, and roughness thereof is such that: Rmax>0.5 (?m).

Abstract: An optical scanning apparatus includes light sources, an aperture having, and coupling lenses. Numbers of the light sources and the coupling lenses are equal to each other and the apparatus satisfies an inequality 12.7 <(D×?0×m0×xdpi)/(2×NA) <38.1 and an equation ?0=(?+???)/(n?1), wherein D represents a width of the slit of the aperture, ?0represents a beam open angle, mo represents a total lateral magnification ratio, dpi represents a number of dots per inch, NA represents a numerical aperture, ?+ represents a positive open angle, ?? represents a negative open angle, and n represents the number. Further, an image forming apparatus using this optical scanning apparatus and an image forming method are provided.

Abstract: An optical system includes three optical systems. The first has a coupling lens. The second includes a lens having a positive power in a vertical scanning direction and forms the light flux into a line image extending in the horizontal scanning direction on a deflector. The third includes a first lens having a positive power in the horizontal scanning direction, and a second lens having a positive power in the vertical scanning direction. Lateral magnification in the horizontal scanning direction is set larger than that in the vertical scanning direction. Temperature near the first lens is maintained higher than that near the second lens.

Abstract: In a multi-beam scanning device and method of the present invention, a semiconductor laser array having a plurality of light emitting parts emitting multiple laser beams is provided. A rotary deflector deflects the laser beams emitted by the light emitting parts of the semiconductor laser array. The deflected laser beams from the rotary deflector is focused onto a scanned surface to form a plurality of beam spots that are separated on the scanned surface in a sub-scanning direction, the scanned surface being scanned simultaneously with the plurality of beam spots in a main scanning direction by a rotation of the rotary deflector.

Abstract: A pixel clock pulse generating apparatus for use in an image forming apparatus includes high frequency clock pulse and pixel clock pulse generators. The high frequency clock pulse generator generates relatively high frequency clock pulses. The pixel clock pulse generator generates pixel clock pulses based on the phase data for instructing a transition time of pixel clock pulses and the high frequency clock pulses.

Abstract: An optical system includes three optical systems. The first has a coupling lens. The second includes a lens having a positive power in a vertical scanning direction and forms the light flux into a line image extending in the horizontal scanning direction on a deflector. The third includes a first lens having a positive power in the horizontal scanning direction, and a second lens having a positive power in the vertical scanning direction. Lateral magnification in the horizontal scanning direction is set larger than that in the vertical scanning direction. Temperature near the first lens is maintained higher than that near the second lens.

Abstract: An image forming lens for forming an image of an original document includes a front side lens group arranged at an object side and a rear side lens group arranged at an image forming side. The front side lens group includes from 2 to 4 lenses including at least one positive lens, and the rear side lens group includes one negative lens. The back-focus of the image forming lens when in use is equal to or smaller than 25% of an entire length of the image forming lens, and the open space between the front side lens group and the rear side lens group is equal to or greater than 50% of the entire length of the image forming lens. The front side lens group lens can include two, three or four pieces of lenses. By configuring an image forming lens with at least three lenses, correction of aberration is easy and high performance can be realized.

Abstract: A plurality of types of engine units which have nonvolatile storage units and which have different performances, respectively, can be attached to an image formation apparatus main body in a replaceable manner. A control unit which controls the performance of an overall apparatus based on information stored in the storage units provided in the engine units, respectively, which are attached to the image formation apparatus main body, is provided in the image formation apparatus main body. Therefore, even if the image formation apparatus main body is common, the performance of the overall apparatus related to recording speed or resolution can be changed only by replacing the engine units different in performance. It is also possible to easily deal with various types of apparatuses.

Abstract: An optical scanning device directs a light beam emitted from a light source to a mirror of a mechanical deflector through a first optical system, deflects the light beam in a main scanning direction by causing the light beam to be reflected by a mirror surface of the mirror, the angle of the mirror surface changing due to rotation of the mirror, and directs the deflected light beam through a second optical system to a surface to be scanned moving in a sub-scanning direction, the light source, first optical system and mechanical deflector being contained in a housing. The mechanical deflector is held in the housing through a holding member, and, also, material of the housing is different in heat conductivity from the holding member.

Abstract: There is provided a multi-beam laser scanning device able to efficiently suppress and prevent density fluctuation and achieve higher image quality. The multi-beam laser scanning device comprises a light emitting source generating a plurality of laser beams, a rotating deflector that has a plurality of deflecting surfaces.

Abstract: An optical scanning device directs a light beam emitted from a light source to a mirror of a mechanical deflector through a first optical system, deflects the light beam in a main scanning direction by causing the light beam to be reflected by a mirror surface of the mirror, the angle of the mirror surface changing due to rotation of the mirror, and directs the deflected light beam through a second optical system to a surface to be scanned moving in a sub-scanning direction, the light source, first optical system and mechanical deflector being contained in a housing. The mechanical deflector is held in the housing through a holding member, and, also, material of the housing is different in heat conductivity from the holding member.

Abstract: In a multi-beam scanning device and method of the present invention, a semiconductor laser array having a plurality of light emitting parts emitting multiple laser beams is provided. A rotary deflector deflects the laser beams emitted by the light emitting parts of the semiconductor laser array. The deflected laser beams from the rotary deflector is focused onto a scanned surface to form a plurality of beam spots that are separated on the scanned surface in a sub-scanning direction, the scanned surface being scanned simultaneously with the plurality of beam spots in a main scanning direction by a rotation of the rotary deflector.

Abstract: A scanning imaging optical component is used in an optical scanning device which deflects a beam from a light source by a light deflector, condenses the deflected beam toward a surface to be scanned by a scanning imaging optical system, forms a beam spot on the surface to be scanned, and performs optical scanning of the surface to be scanned. The optical component forms at least a part of the scanning imaging optical system, and at least a part of a surface of the optical component other than an effective optical surface is made to be a roughened surface, and roughness thereof is such that: Rmax>0.5 (&mgr;m).

Abstract: A scanning imaging optical component is used in an optical scanning device which deflects a beam from a light source by a light deflector, condenses the deflected beam toward a surface to be scanned by a scanning imaging optical system, forms a beam spot on the surface to be scanned, and performs optical scanning of the surface to be scanned. The optical component forms at least a part of the scanning imaging optical system, and at least a part of a surface of the optical component other than an effective optical surface is made to be a roughened surface, and roughness thereof is such that: Rmax>0.5 (&mgr;m).

Abstract: An optical scanning apparatus includes light sources, an aperture having, and coupling lenses. Numbers of the light sources and the coupling lenses are equal to each other and the apparatus satisfies an inequality 12.7 <(Dx&bgr;oxmoxdpi)/(2xNA) <38.1 and an equation &bgr;o=(&bgr;+−&bgr;)/(n-1), wherein D represents a width of the slit of the aperture, &bgr;orepresents a beam open angle, mo represents a total lateral magnification ratio, dpi represents a number of dots per inch, NA represents a numerical aperture, &bgr;+represents a positive open angle, &bgr; represents a negative open angle, and n represents the number. Further, an image forming apparatus using this optical scanning apparatus and an image forming method are provided.

Abstract: In a multi-beam scanning device and method of the present invention, a semiconductor laser array having a plurality of light emitting parts emitting multiple laser beams is provided. A rotary deflector deflects the laser beams emitted by the light emitting parts of the semiconductor laser array. The deflected laser beams from the rotary deflector is focused onto a scanned surface to form a plurality of beam spots that are separated on the scanned surface in a sub-scanning direction, the scanned surface being scanned simultaneously with the plurality of beam spots in a main scanning direction by a rotation of the rotary deflector.

Abstract: An optical system includes three optical systems. The first has a coupling lens. The second includes a lens having a positive power in a vertical scanning direction and forms the light flux into a line image extending in the horizontal scanning direction on a deflector. The third includes a first lens having a positive power in the horizontal scanning direction, and a second lens having a positive power in the vertical scanning direction. Lateral magnification in the horizontal scanning direction is set larger than that in the vertical scanning direction. Temperature near the first lens is maintained higher than that near the second lens.

Abstract: A pixel clock pulse generating apparatus for use in an image forming apparatus includes high frequency clock pulse and pixel clock pulse generators. The high frequency clock pulse generator generates relatively high frequency clock pulses. The pixel clock pulse generator generates pixel clock pulses based on the phase data for instructing a transition time of pixel clock pulses and the high frequency clock pulses.

Abstract: A multi-beam scanning apparatus including a light source unit having a plurality of light emitting parts configured to emit a plurality of divergent light fluxes, a deflector configured to deflect the plurality of divergent light fluxes emitted from the light source unit, and an imaging system configured to couple the plurality of divergent light fluxes from the light source unit with the deflector and to condense the deflected plurality of light fluxes into optical spots on a surface to be scanned. The light source unit is configured so the optical spots are separated from each other in a sub-scanning direction on the surface to be scanned, and optical axes of the light fluxes emitted from the plurality of light emitting parts are angled in a substantially same direction in the sub-scanning direction relative to optical axes of respective corresponding coupling lenses.