Abstract: Reflection surfaces (2, 3) and a diaphragm (1) for limiting light fluxes disposed between an object and the reflection surface (2) that is located closest to the object are provided. At least one surface of the plural reflection surfaces (2, 3) has an anamorphic shape. The reflection surfaces (2, 3) are disposed eccentrically. There is provided a light shielding member (6) for blocking light fluxes passing through the diaphragm (1) and reaches the range to be imaged on an image surface (4) without being reflected by the reflection surfaces (2, 3). Since the shielding member (6) is disposed, unnecessary light fluxes do not reach the image surface directly. Since there is no refractive transmission plane, also unnecessary light reflected by the transmission plane does not reach the image surface.

Abstract: Two reflection surfaces that are a first reflection surface (2) and a second reflection surface (3), each in a non-axisymmetric form, are disposed in the stated order in a direction in which light fluxes travel, and bring light fluxes from an object into focus on an image surface (4). The first reflection surface (2) and the second reflection surface (3) are provided eccentrically, and each of the first reflection surface (2) and the second refection surface (3) is concave in a cross-sectional shape taken along a plane containing a center of the image surface (4) and vertices of the reflection surfaces (2, 3). This ensures that light fluxes are guided to the image surface without being blocked, whereby an excellent image can be formed. Thus, a reflective optical device with a wider angle and improved performance can be provided.

Abstract: The over-field type optical scanner includes a first imaging optical system disposed between a light source and a rotating polygon mirror for forming, on one surface of the rotating polygon mirror, a linear image with a width larger than a width along a main scanning direction of the one surface of the rotating polygon mirror; and a second imaging optical system composed of a curved mirror for focusing, on a scan surface, a light beam having been reflected by the rotating polygon mirror. The first imaging optical system includes a first conversion optical system for converting the light beam emitted from the light source into a divergent light beam with respect to the main scanning direction and into a convergent light beam with respect to the sub scanning direction; and a second conversion optical system having a refracting power in the main scanning direction.

Abstract: Two reflection surfaces that are a first reflection surface (2) and a second reflection surface (3), each in a non-axisymmetric form, are disposed in the stated order in a direction in which light fluxes travel, and bring light fluxes from an object into focus on an image surface (4). The first reflection surface (2) and the second reflection surface (3) are provided eccentrically, and each of the first reflection surface (2) and the second refection surface (3) is concave in a cross-sectional shape taken along a plane containing a center of the image surface (4) and vertices of the reflection surfaces (2, 3). This ensures that light fluxes are guided to the image surface without being blocked, whereby an excellent image can be formed. Thus, a reflective optical device with a wider angle and improved performance can be provided.

Abstract: A light quantity distribution control element includes a substrate of 20 mm×20 mm×3 mm made of a material that transmits light, such as optical glass or acryl, and a antireflective structure provided on a surface of the substrate. As the antireflective structure, a conical antireflective structure of a pitch of 0.15 ?m (periodic structure having conical convexities) is formed. This corresponds to a antireflective structure having a pitch of a wavelength or less in the ultraviolet band (150 nm to 400 nm) at the time when ultraviolet light is used as incident light.

Abstract: A wide-angle imaging optical system includes a refractive optical system (3), a reflective optical system, and an image-forming optical system (5). The reflective optical system includes a first reflection surface (1) that directly reflects rays of light from an object, and a second reflection surface (2) that reflects rays of light from the first reflection surface (1). An open portion is provided between the first reflection surface (1) and the second reflection surface (2), and rays of light from the object enter the open portion. A light-transmitting portion (2a) is provided in the second reflection surface (2) and transmits rays of light that have entered the refractive optical system (3). An aperture (1a) is provided in the first reflection surface (1) and allows rays of light from the second reflection surface (2) and the refractive optical system (3) to enter the image-forming optical system (5).

Abstract: An optical scan apparatus includes an optical deflection unit (4), an image formation optical system (3), and curved surface mirrors (7a to b 7d). Light fluxes from the image formation optical system (3) come onto the deflection surface (4a) of die optical deflection unit (4) in an oblique direction. Light fluxes from the optical deflection unit (4) come onto the curved surface mirrors (7a to 7d) in an oblique direction. When a boundary is a plane (6) including a normal at the center of the deflection surface (4a) and parallel to the main scan direction, the curved surface mirrors (7a to 7d) are arranged in the same space divided by the boundary and the scan speeds of fluxes scanning the surfaces to be scanned (8a to 8d) are almost identical. Thus, it is possible to obtain identical drive frequencies of the light sources (1a to 1d), thereby simplifying the circuit.

Abstract: An image reading device comprising a rotary polygon mirror (6) for scanning a light flux from a light source (1), an imaging optical system (4) for forming in a reflection plane of the mirror (6) a linear image larger than the width in a main scanning direction of the one reflection plane, and a curved-face mirror (7), wherein the light source (1) , the imaging optical system (4), the rotary polygon mirror (6) and the curved-face mirror (7) are disposed in different positions in a sub-scanning direction, a light flux from the imaging optical system (4) shines obliquely onto the polygon mirror (6), and a light flux reflected off the mirror (6) beams obliquely onto the curved-face mirror (7). Since one curved-face mirror can beam a light flux reflected from the rotary polygon mirror onto a surface to be scanned and the rotary polygon mirror having a small inscribed radius and many reflection planes can be used, satisfactory optical performance and high-speed feature can be realized.

Abstract: Two reflection surfaces that are a first reflection surface (2) and a second reflection surface (3), each in a non-axisymmetric form, are disposed in the stated order in a direction in which light fluxes travel, and bring light fluxes from an object into focus on an image surface (4). The first reflection surface (2) and the second reflection surface (3) are provided eccentrically, and each of the first reflection surface (2) and the second refection surface (3) is concave in a cross-sectional shape taken along a plane containing a center of the image surface (4) and vertices of the reflection surfaces (2, 3). This ensures that light fluxes are guided to the image surface without being blocked, whereby an excellent image can be formed. Thus, a reflective optical device with a wider angle and improved performance can be provided.

Abstract: Reflection surfaces (2, 3) and a diaphragm (1) for limiting light fluxes disposed between an object and the reflection surface (2) that is located closest to the object are provided. At least one surface of the plural reflection surfaces (2, 3) has an anamorphic shape. The reflection surfaces (2, 3) are disposed eccentrically. There is provided a light shielding member (6) for blocking light fluxes passing through the diaphragm (1) and reaches the range to be imaged on an image surface (4) without being reflected by the reflection surfaces (2, 3). Since the shielding member (6) is disposed, unnecessary light fluxes do not reach the image surface directly. Since there is no refractive transmission plane, also unnecessary light reflected by the transmission plane does not reach the image surface.

Abstract: An optical scanner having excellent optical performance and guiding a light beam from one curved mirror directly to a photoconductive drum without requiring a reflecting mirror. The optical scanner includes: a light source unit (1); an optical deflector (5) for deflecting a light beam from the light source unit so as to cause scanning; a first image formation optical system (2, 3) for forming a line image on a deflection surface of the optical deflector, which is disposed between the light source unit and the optical deflector; and a second image formation optical system (7) composed of one curved mirror, which is disposed between the optical deflector and a surface (8) to be scanned.

Abstract: An illuminating device comprising a light source for emitting a plurality of light beams (207, 208, 209) of different colors, a plurality of rotating beam scanners (102, 103, 104) and a plurality of scanning lenses (109, 110, 111). The beam scanners have spiral reflection surfaces (102, 103, 204) formed on the outer peripheries of cylindrical bodies, Each colored light beam is shone onto each reflection surface from a direction parallel to a rotating axis, and magnified by each scanning lens after reflected to scan an illuminated area with a plurality of beams of different colors one after another. Accordingly, the illuminating device can enhance scanning linearity, reduce noise due to a minimal windage loss, and decrease costs and power consumption.

Abstract: A high-performance optical scanner in which the f.theta. characteristics and the field curvature are compensated excellently by shifting an optical deflector by an optimum amount and using a collecting lens that can be processed easily. The optical scanner includes, in one embodiment: a semiconductor laser 1; a polygon mirror 4 as an optical deflector; a cylindrical lens 3 as a first imaging optical system; and a correcting lens 6 as a second imaging optical system formed of one correcting lens having a curved-axis toric surface. A formula of 0.15<{.DELTA.X.multidot.cos (.alpha./2)}/rp<0.35 is satisfied, wherein .DELTA.X indicates a shift amount that is the distance between a reflecting point at a scanning center and the center of a deflecting plane, .alpha. represents an angle of reflection on the deflecting plane at the scanning center, and rp denotes the radius of an inscribed circle in the polygon mirror 4.

Abstract: In treatment of water by injection of ozone into the water for removal of harmful matters, odor matters, and color matters therein, either or both of a nonyl phenol and a cresol are added to the water to be treated. The nonyl phenol is added together with a lower alcohol or acetone to the water to be treated. The cresol is added together with a lower alcohol or acetone to the water to be treated. A p-nonyl phenol is added as the nonyl phenol for treatment. As the cresol for addition, a p-cresol is added. As the nonyl phenol for addition, a nonyl phenol is used such that two molecular weights of 220 and 107 are detected when measured by either or both of gas chromatography and mass spectrometry. By the above treatment, the decomposition reaction of ozone can be accelerated, and thereby it becomes possible to accelerate the oxidative decomposition reaction of organic matters, the amount of ozone required for the decomposition of harmful matters can be reduced with the decomposition time.

Abstract: A display device comprises a transparent type LCD including a pair of transparent plates facing each other, spaced with a predetermined gap and a polymer dispersed liquid crystal disposed between the transparent plates, which can be switched between a transparent state and a diffraction state pixel by pixel to display images or characters; a signal generator for giving display signals to the transparent type LCD; and a light system including a light source emitting light rays that enter the transparent plates from their edge faces, and a stop plate disposed between the edge faces of the transparent plates and the light source. This stop plate has an opening that extends along the longitudinal direction of the edge face of the transparent plate, and the width of the opening in the cross direction changes cyclically along the longitudinal direction.

Abstract: The light source equipment is provided with a light source and an anamorphic single lens. The anamorphic single lens has different refracting powers in the x and y directions orthogonal to each other, and converts a light from the light source to a light beam in a required state. Farther the anamorphic single lens satisfies the following equation :0.3<2.multidot.fy.multidot.tan (.theta.y/2)<0.7fy>fxwhere fx is a focal length in the x direction, fy is a focal length in the y direction, and .theta.y is a half angular divergence of radiant intensity of the light in the y direction.

Abstract: A plurality of types of ink having different wavelength characteristics are used for multiple printing of code information. When two or more types of ink are to be printed in an overlapping manner, in a region 8 in which one type of ink 4 and another type of ink 5 are printed in the overlapping manner, the ink 4 and the ink 5 are printed so as not to completely overlap each other by using a checkered pattern 9. As a result, the multiple printing can be performed without strict constraints on the wavelength characteristics of the ink.

Abstract: An optical scanner comprising a light source unit, an optical deflector to scan a light beam from the light source unit, a first image formation optical system disposed between the light source unit and the optical deflector, and a second image formation optical system disposed between the optical deflector and the surface to be scanned, wherein the second image formation optical system comprises a first curved mirror to reflect the light beam from the optical deflector and a second curved mirror to focus the light beam from the first curved mirror on the surface to be scanned, having surface shapes of any of the group consisting of the first curved mirror having a toric surface with a convex shape in the main scanning direction, which is the direction a light beam is scanned in, and with a concave shape in the sub scanning direction, which is the direction perpendicular to the main scanning direction, and the first curved mirror having a toric surface with a concave shape in the main scanning direction and a

Abstract: An optical scanner comprising a light source unit, an optical deflector to scan a light beam from the light source unit, a first image formation optical system disposed between the light source unit and the optical deflector, and a second image formation optical system disposed between the optical deflector and the surface to be scanned, wherein the second image formation optical system comprises a first curved mirror to reflect the light beam from the optical deflector and a second curved mirror to focus the light beam from the first curved mirror on the surface to be scanned, having surface shapes of any of the group consisting of the first curved mirror having a toric surface with a convex shape in the main scanning direction, which is the direction a light beam is scanned in, and with a concave shape in the sub scanning direction, which is the direction perpendicular to the main scanning direction, and the first curved mirror having a toric surface with a concave shape in the main scanning direction and a

Abstract: The scanner optics of this invention includes a condensing lens arrangement composed of a first aspherical lens having a positive refractive power and a convex meniscus surface on the side of the scanning surface and a second toric lens of which incident surface is saddle toroidal where a point on the incident surface has a greater radius of curvature in the sub-scanning direction as the point is farther from the optical axis in the scanning direction. A laser light flux emitted from a light source is deflected and scanned by a polygon mirror so as to form an image on a scanning surface via the condensing lens arrangement.