Abstract: An optical scanning device includes: a light source; an optical deflecting unit that deflects a light beam emitted from the light source to scan on a scanning surface in main-scanning direction; and a scanning optical system that includes a first scanning lens and a second scanning lens that converge the light beam that is deflected onto the scanning surface. Distance between an exit surface of the first scanning lens and an incident surface of the second scanning lens is shorter than distance between a deflection facet of the optical deflecting unit and an incident surface of the first scanning lens, an exit surface of the second scanning lens is nearer to the deflection facet than a midpoint between the deflection facet and the scanning surface, and an image-surface-side principal point of the scanning optical system in sub-scanning direction is nearer to the scanning surface than the midpoint.

Abstract: An optical scanner includes a plurality of scanning optical systems each of which scans a different surface to be scanned and includes a light source configured to emit a light beam, an optical deflector having a plurality of reflection surfaces, and a synchronization detector configured to receive the light beam deflected by the optical deflector and detect a timing to scan an effective area of the surface to be scanned with the deflected light beam before a scanning is started or after the scanning is completed. The synchronization detector of one of a pair of scanning optical systems is disposed on a scanning end side to determine the scanning timing, and the synchronization detector of the other one of the pair of scanning optical systems is disposed on a scanning start side to determine the scanning timing.

Abstract: Each scanning optical system includes a first scanning lens and a second scanning lens through which a light beam is incident onto the first scanning lens. The second scanning lens of each scanning optical system is disposed at the optically most downstream side in the scanning optical system and has an optical plane that has the strongest power in a sub-scanning corresponding direction. In addition, the optical plane of each second scanning lens, which has the strongest power in the sub-scanning corresponding direction, is located under the shaft bearings of neighboring polygon mirrors in the vertical direction.

Abstract: A prepreg containing a carbon fiber [A] and a thermosetting resin [B], and in addition, satisfying at least one of the following (1) and (2). (1) a thermoplastic resin particle or fiber [C] and a conductive particle or fiber [D] are contained, and weight ratio expressed by [compounding amount of [C] (parts by weight)]/[compounding amount of [D] (parts by weight)] is 1 to 1000. (2) a conductive particle or fiber of which thermoplastic resin nucleus or core is coated with a conductive substance [E] is contained.

Abstract: A prepreg containing a carbon fiber [A] and a thermosetting resin [B], and in addition, satisfying at least one of the following (1) and (2) (1) a thermoplastic resin particle or fiber [C] and a conductive particle or fiber [D] are contained, and weight ratio expressed by [compounding amount of [C] (parts by weight)]/[compounding amount of [D] (parts by weight)] is 1 to 1000. (2) a conductive particle or fiber of which thermoplastic resin nucleus or core is coated with a conductive substance [E] is contained.

Abstract: An optical scanner includes a housing and an intermediate member that includes a first joining surface and a second joining surface. The first joining surface is attached to the housing and the second joining surface is attached to at least one optical element of any one of a first optical system and a second optical system. In a three-dimensional coordinate in which a first one of coordinate axes is a direction that is parallel to both the first joining surface and the second joining surface, a second range on the first coordinate axis corresponding to the second joining surface includes a center point of a first range on the first coordinate axis corresponding to the first joining surface.

Abstract: A prepreg containing a carbon fiber [A] and a thermosetting resin [B], and in addition, satisfying at least one of the following (1) and (2). (1) a thermoplastic resin particle or fiber [C] and a conductive particle or fiber [D] are contained, and weight ratio expressed by [compounding amount of [C] (parts by weight)]/[compounding amount of [D] (parts by weight)] is 1 to 1000. (2) a conductive particle or fiber of which thermoplastic resin nucleus or core is coated with a conductive substance [E] is contained.

Abstract: A prepreg containing a carbon fiber [A] and a thermosetting resin [B], and in addition, satisfying at least one of the following (1) and (2). (1) a thermoplastic resin particle or fiber [C] and a conductive particle or fiber [D] are contained, and weight ratio expressed by [compounding amount of [C] (parts by weight)]/[compounding amount of [D] (parts by weight)] is 1 to 1000. (2) a conductive particle or fiber of which thermoplastic resin nucleus or core is coated with a conductive substance [E] is contained.

Abstract: A prepreg containing a carbon fiber [A] and a thermosetting resin [B], and in addition, satisfying at least one of the following (1) and (2). (1) a thermoplastic resin particle or fiber [C] and a conductive particle or fiber [D] are contained, and weight ratio expressed by [compounding amount of [C] (parts by weight)]/[compounding amount of [D] (parts by weight)] is 1 to 1000. (2) a conductive particle or fiber of which thermoplastic resin nucleus or core is coated with a conductive substance [E] is contained.

Abstract: A surface-emitting laser array includes a plurality of surface-emitting laser devices arranged in an array. An optical system includes a plurality of optical devices to guide a light beam composed of lights emitted from the surface-emitting laser array to a target surface to be scanned. A light-intensity-control-device switching unit places one of light-intensity control devices having different light transmittances at a predetermined position in an optical path of the light beam.

Abstract: An optical scanner includes a light source, a deflector and a scanning optical system. The scanning optical system includes a first optical system including at least one resin scanning lens, and a second optical system between the target surface and one resin scanning lens. The second optical system includes at least one of a folding mirror(s) and a glass sheet(s), wherein m1+g2=m2+g1 is satisfied wherein m1 and g1 are respectively number of the folding mirror(s) and number of the glass sheet(s) to which the first ray has a shorter optical path than the second ray does, m2 and g2 are respectively number of the folding mirror(s) and number of the glass sheet(s) to which the first ray has a longer optical path than the second ray does.

Abstract: A prepreg containing a carbon fiber [A] and a thermosetting resin [B], and in addition, satisfying at least one of the following (1) and (2). (1) a thermoplastic resin particle or fiber [C] and a conductive particle or fiber [D] are contained, and weight ratio expressed by [compounding amount of [C] (parts by weight)]/[compounding amount of [D] (parts by weight)] is 1 to 1000. (2) a conductive particle or fiber of which thermoplastic resin nucleus or core is coated with a conductive substance [E] is contained.

Abstract: A prepreg containing a carbon fiber [A] and a thermosetting resin [B], and in addition, satisfying at least one of the following (1) and (2). (1) a thermoplastic resin particle or fiber [C] and a conductive particle or fiber [D] are contained, and weight ratio expressed by [compounding amount of [C] (parts by weight)]/[compounding amount of [D] (parts by weight)] is 1 to 1000. (2) a conductive particle or fiber of which thermoplastic resin nucleus or core is coated with a conductive substance [E] is contained.

Abstract: An optical scanning system for a K station includes a resin scanning lens and three reflecting mirrors. Two reflectance ratios are calculated: one being the reflectance ratio of a luminous flux traveling toward the scanning start position of a drum-shaped photosensitive drum and the other being the reflectance ratio of a luminous flux traveling toward the scanning end position of the photosensitive drum. The magnitude relation between the two reflectance ratios is such that the reflecting mirror has an inverse magnitude relation to that of the other reflecting mirrors. Moreover, the difference is calculated between the largest value and the smallest value of the reflectance ratio, where the reflectance ratio depends on the angle of deviation of the polygon mirror. The reflecting mirror has the largest difference among the three reflecting mirrors.

Abstract: A prepreg containing a carbon fiber [A] and a thermosetting resin [B], and in addition, satisfying at least one of the following (1) and (2). (1) a thermoplastic resin particle or fiber [C] and a conductive particle or fiber [D] are contained, and weight ratio expressed by [compounding amount of [C] (parts by weight)]/[compounding amount of [D] (parts by weight)] is 1 to 1000. (2) a conductive particle or fiber of which thermoplastic resin nucleus or core is coated with a conductive substance [E] is contained.

Abstract: An optical scanner includes a light source including light emitters, an aperture member collimating light beams from the light source, a deflector deflecting the light beams passing through the aperture member, and a scanning optical system condensing the deflected light beams onto a scanned surface to optically scan the surface in a main-scanning direction. The scanning optical system includes a resin scanning system having at least one resin scanning lens. At least one folding mirror/sheet glass is disposed between a scanning lens nearest to the deflector in the resin scanning system and the scanned surface. At least one scanning lens in the resin scanning system has an uneven birefringence distribution with respect to a sub-scanning direction. An optical conjugate image of the aperture member is formed between a lens surface nearest to the deflector in the resin scanning system and a lens surface nearest to the scanned surface with respect to the sub-scanning direction.

Abstract: An optical scanning device includes: a light source; an optical deflecting unit that deflects a light beam emitted from the light source to scan on a scanning surface in main-scanning direction; and a scanning optical system that includes a first scanning lens and a second scanning lens that converge the light beam that is deflected onto the scanning surface. Distance between an exit surface of the first scanning lens and an incident surface of the second scanning lens is shorter than distance between a deflection facet of the optical deflecting unit and an incident surface of the first scanning lens, an exit surface of the second scanning lens is nearer to the deflection facet than a midpoint between the deflection facet and the scanning surface, and an image-surface-side principal point of the scanning optical system in sub-scanning direction is nearer to the scanning surface than the midpoint.

Abstract: A prepreg containing a carbon fiber [A] and a thermosetting resin [B], and in addition, satisfying at least one of the following (1) and (2). (1) a thermoplastic resin particle or fiber [C] and a conductive particle or fiber [D] are contained, and weight ratio expressed by [compounding amount of [C] (parts by weight)]/[compounding amount of [D] (parts by weight)] is 1 to 1000. (2) a conductive particle or fiber of which thermoplastic resin nucleus or core is coated with a conductive substance [E] is contained.

Abstract: A surface-emitting laser array includes a plurality of surface-emitting laser devices arranged in an array. An optical system includes a plurality of optical devices to guide a light beam composed of lights emitted from the surface-emitting laser array to a target surface to be scanned. A light-intensity-control-device switching unit places one of light-intensity control devices having different light transmittances at a predetermined position in an optical path of the light beam.

Abstract: By setting elements within the range that predetermined conditions are satisfied, for example, so that a size of a rotating polygon mirror is minimized, the rotating polygon mirror is made compact while the eclipse of light beams in the main scanning direction is prevented. The cost reduction of an apparatus is thus realized. The compact rotating polygon mirror reduces the consumption energy and the amount of heat generated in its drive system. Deteriorations in various optical characteristics including an increase in spot diameter of the light beam by temperature variation, uneven scanning pitch, and sub-scanning direction variation in beam pitch are suppressed.