Abstract: A light flux emitted from a light source is split into two by a light flux splitting unit, and these are respectively made incident on upper and lower tiers of polygon mirrors of a deflecting unit which coaxially rotates two polygon mirrors one on the other while being shifted in angles from each other. The respective light fluxes that have been deflected for scanning at mutually different timings by the deflecting unit respectively reach individual photodetectors through a first scanning lens, mirrors, and a second scanning lens as a predetermined light system and carry out main scanning.

Abstract: A photosensitive body has a photosensitive layer. An optical scanning device has a deflector deflecting a light flux emitted from a light source, and scans the surface of the photosensitive body by the thus-deflected light flux. A dot is formed at a center between adjacent light fluxes as a result of the adjacent light fluxes being overlapped with one another in a sub-scan direction. A ratio of a static beam-spot diameter Ws in the sub-scan direction on the surface of the photosensitive body defined by 1/e2 of the maximum value in the exposure distribution of the beam spot to an interval L between adjacent scan lines satisfies the following formula: 1.2<Ws/L<4.5.

Abstract: A light flux emitted from a light source is split into two by a light flux splitting unit, and these are respectively made incident on upper and lower tiers of polygon mirrors of a deflecting unit which coaxially rotates two polygon mirrors one on the other while being shifted in angles from each other. The respective light fluxes that have been deflected for scanning at mutually different timings by the deflecting unit respectively reach individual photodetectors through a first scanning lens, mirrors, and a second scanning lens as a predetermined light system and carry out main scanning.

Abstract: An optical scanning lens is used in a scanning and image forming optical system which gathers a light flux deflected by a light deflector in the vicinity of a surface to be scanned. The lens is formed by plastic molding of polyolefin resin, and the following condition is satisfied: 0<|?n(x)?min[?n(x)]|<34×10?5, where ?n(x) denotes a refractive-index distribution existing inside the lens, in a range which the light flux passes through, in the lens, and min[?n(x)] denotes the minimum value of the ?n(x).

Abstract: An optical scanning lens is used in a scanning and image forming optical system which gathers a light flux deflected by a light deflector in the vicinity of a surface to be scanned. The lens is formed by plastic molding of polyolefin resin, and the following condition is satisfied: 0<|?n(x)?min[?n(x)]|<34×10?5, where ?n(x) denotes a refractive-index distribution existing inside the lens, in a range which the light flux passes through, in the lens, and min[?n(x)] denotes the minimum value of the ?n(x).

Abstract: An optical scanning lens which is used in a scanning and age forming optical system which gathers a light flux deflected by a light deflector in the vicinity of a surface to be scanned. The lens is formed by plastic molding of polyolefin resin, and the following condition is satisfied: 0<|?n(x)?min[?n(x)]|<34×10?5, where ?n(x) denotes a refractive-index distribution existing inside the lens, in a range which the light flux passes through, in the lens, and min[?n(x)] denotes the minimum value of the ?n(x).

Abstract: A photosensitive body has a photosensitive layer. An optical scanning device has a deflector deflecting a light flux emitted from a light source, and scans the surface of the photosensitive body by the thus-deflected light flux. A dot is formed at a center between adjacent light fluxes as a result of the adjacent light fluxes being overlapped with one another in a sub-scan direction. A ratio of a static beam-spot diameter Ws in the sub-scan direction on the surface of the photosensitive body defined by 1/e2 of the maximum value in the exposure distribution of the beam spot to an interval L between adjacent scan lines satisfies the following formula: 1.2<Ws/L<4.5.

Abstract: A photosensitive body has a photosensitive layer. An optical scanning device has a deflector deflecting a light flux emitted from a light source, and scans the surface of the photosensitive body by the thus-deflected light flux. A dot is formed at a center between adjacent light fluxes as a result of the adjacent light fluxes being overlapped with one another in a sub-scan direction. A ratio of a static beam-spot diameter Ws in the sub-scan direction on the surface of the photosensitive body defined by 1/e2 of the maximum value in the exposure distribution of the beam spot to an interval L between adjacent scan lines satisfies the following formula: 1.2<Ws/L<4.5.

Abstract: An optical scanning lens which is used in a scanning and age forming optical system which gathers a light flux deflected by a light deflector in the vicinity of a surface to be scanned. The lens is formed by plastic molding of polyolefin resin, and the following condition is satisfied: 0<|&Dgr;n(x)−min [&Dgr;n(x)]|<34×10−5, where &Dgr;n(x) denotes a refractive-index distribution existing inside the lens, in a range which the light flux passes through, in the lens, and min [&Dgr;n(x)] denotes the minimum value of the &Dgr;n(x).

Abstract: An optical scanning lens is used in a scanning and image forming optical system which gathers a light flux deflected by a light deflector in the vicinity of a surface to be scanned. The lens is formed by plastic molding of polyolefin resin, and the following condition is satisfied: 0<|&Dgr;n(x)−min[&Dgr;n(x)]|<34×10−5, where &Dgr;n(x) denotes a refractive-index distribution existing inside the lens, in a range which the light flux passes through, in the lens, and min[&Dgr;n(x)] denotes the minimum value of the &Dgr;n(x).

Abstract: An optical scanning lens is used in a scanning and image forming optical system which gathers a light flux deflected by a light deflector in the vicinity of a surface to be scanned. The lens is formed by plastic molding of polyolefin resin, and the following condition is satisfied: 0<|&Dgr;n(x)−min[&Dgr;n(x)]|<34×10−5, where &Dgr;n(x) denotes a refractive-index distribution existing inside the lens, in a range which the light flux passes through, in the lens, and min[&Dgr;n(x)] denotes the minimum value of the &Dgr;n(x).

Abstract: An optical scanning lens is used in a scanning and image forming optical system which gathers a light flux deflected by a light deflector in the vicinity of a surface to be scanned. The lens is formed by plastic molding of polyolefin resin, and the following condition is satisfied: 0<|&Dgr;n(x)−min[&Dgr;n(x)]|<34×10−5, where &Dgr;n(x) denotes a refractive-index distribution existing inside the lens, in a range which the light flux passes through, in the lens, and min[&Dgr;n(x)] denotes the minimum value of the &Dgr;n(x).

Abstract: A photosensitive body has a photosensitive layer. An optical scanning device has a deflector deflecting a light flux emitted from a light source, and scans the surface of the photosensitive body by the thus-deflected light flux. A dot is formed at a center between adjacent light fluxes as a result of the adjacent light fluxes being overlapped with one another in a sub-scan direction. A ratio of a static beam-spot diameter Ws in the sub-scan direction on the surface of the photosensitive body defined by 1/e2 of the maximum value in the exposure distribution of the beam spot to an interval L between adjacent scan lines satisfies the following formula: 1.2<Ws/L<4.5.

Abstract: An optical scanning device includes a light source, a coupling lens, an optical deflector, an aperture and a scanning image-forming optical system. The central wavelength of the light flux emitted by the light source is less than about 680 nm, and NAO, &kgr;, &bgr;0 satisfy &bgr;0/(NAO•&kgr;)<100, and NAO satisfies 0.18<NAO<0.35, where: NAO represents the light-source-side numerical aperture of the coupling lens; &kgr; represents the ratio A/D of the larger diameter A of the diameters, in a main scanning direction and a sub-scanning direction, of the opening of the aperture relative to the diameter D of the light flux emitted from the coupling lens; and &bgr;0 represents the larger one of the lateral magnifications, in the main scanning direction and the sub-scanning direction, of the entire optical system with respect to an optical path extending from the light source to the surface to be scanned, and including a point of the image surface, at which point the image height is 0.

Abstract: A reading lens for a scanner to read an original in a reduced magnification, the lens comprising six lenses, i.e., from a first lens to a sixth lens in order on an optical axis. The first lens is a positive lens having a first lens-surface and a second lens-surface. The second lens is a negative lens disposed in contact with the first lens and has the second lens-surface in common with the first lens and a third lens-surface. The third lens is a meniscus lens and has a fourth lens-surface and a fifth lens-surface. The fourth lens is a meniscus lens and has a sixth lens-surface and a seventh lens-surface. The fifth lens is a negative lens and has a eighth lens-surface and a ninth lens-surface. The sixth lens is a positive lens disposed in contact with the fifth lens and has the ninth lens-surface in common with the fifth lens and a tenth lens-surface. At least one of the ten lens-surfaces is formed as an aspherical surface.

Abstract: A copier lens system having a large aperture has a basic structure of 6-unit-6-element arrangement which is constructed by separating the first and second lenses of the orthmeta type lens system.

Abstract: A plastic lens assembly for use in a copying machine is a four-element configuration or a six-element configuration. The lens assembly has an aperture stop and is completely symmetrical with respect to the aperture stop. With the four-element lens assembly, all of the four lenses are made of plastics. Where the six-element lens design is employed, at least second through fifth lenses are made of plastics. The lens assembly are designed to sufficiently reduce variations in the focal length which would otherwise be caused by varying temperature and humidity.

Abstract: A copying lens having a wide angle of view is of a six-component, eighth-element configuration which is completely symmetrical with respect to an aperture stop. The first component is composed of a convex-meniscus lens having a convex surface directed toward the object side, and the second component is composed of a concave-meniscus lens having a convex surface directed toward the object side. The third component is composed of a double-convex lens and a double-concave lens which are joined to each other, with the double-convex lens being closer to the object side. The fourth, fifth, and sixth components are substantially same as the third, second, and first components. The fourth and third components, the fifth and second groups, and the sixth and first components are symmetrical with respect to the aperture stop. The copying lens meets the following conditions:(i) 0.45<f/f.sub.1.2 <0.6;(ii) 0.1<f/f.sub.3.4 <0.25(iii) 0.1<n.sub.4 -n.sub.3 <0.3;(iv) 15<.nu..sub.3 -.nu..sub.

Abstract: Disclosed is a color separating a color separating lens composed of 3 lens units which is small in number of lenses, can be manufactured at less cost and can provide a good focusing performance over the entire visible area.

Abstract: This invention relates to a completely symmetrical wide angle copying lens system for a compact copying machine using a high output lamp. A topogon type wide angle lens system which is easy in correction of a radial curvature of field is basically used, and positive meniscus lenses having a small refracting power with a convex surface directed toward a diaphragm are symmetrically arranged with the diaphragm placed therebetween. A copying lens system is provided in which the tangential curvature of field and a deviation of the field cased by color are corrected by the construction as described above, the overall length of the lens system is shortened and even if a copying magnification is changed in the range of from .times.0.5 to .times.2.0, the performance is not deteriorated.