Abstract: A beam splitting element includes a transparent substrate and a diffractive grating formed on the substrate for dividing an incident beam into a plurality of diffracted beams. The diffractive grating has a plurality of identically formed belt-shaped phase patterns that are arranged in parallel lines at equal pitches. The phase pattern has a sectional shape in a plane perpendicular to the parallel lines that causes non-linear phase difference to the beam passing therethrough within one pitch. Further, the adjacent phase patterns are connected without phase gaps at the boundaries therebetween.

Abstract: A scanning-type image reading device is provided which includes an image sensor, a rotating-type scanning system, a focusing mechanism, and a controller. The controller may control the focusing mechanism for each rotational position of the rotating-type scanning system. In a particular case, the controller may control the focusing mechanism according to the rotational position of the rotating-type scanning system and according to an initial position of the focusing mechanism determined at a predetermined position of the rotating-type scanning system.

Abstract: A reflection type projector includes a light source, a reflection type light modulating element, a projection lens, a condenser lens, and first and second adjusting mechanisms. An illumination light emitted from the light source passes through the condenser lens and enters into the reflection type light modulating element. The reflected light from the element passes through the condenser lens and is projected on the screen to form an image through the projection lens. The first adjusting mechanism adjusts the position of the projection lens along a direction perpendicular to the optical axis of the projection lens to move the position of the projected image. The second adjusting mechanism adjusts the position of the condenser lens along a direction parallel to the adjusting direction of the projection lens so that the reflected light enters into the projection lens.

Abstract: A scanning optical system includes a light source for emitting a beam of light and a first optical system that changes a cross-sectional shape of the beam into an oblong shape along a main scanning direction. A light deflector deflects the oblong cross-sectioned beam of light in the main scanning direction, and a second optical system receives a beam of light deflected by the light deflector for focusing the deflected beam of light onto a scanning surface. At least one surface of a lens in the first optical system is formed as a sub-scanning-plane aspherical surface so as to correct the spherical aberration of the scanning optical system in a sub-scanning direction caused by the second optical system.

Abstract: Disclosed is a scanning optical system, which is provided with a light source that emits a light beam, a deflector that deflects the light beam emitted by the light source to scan along a main scanning direction, and a single mirror that reflects the light beam deflected by the deflector towards a surface to be scanned. The single mirror is arranged such that the light beam deflected by the deflector and is incident on the single mirror and a light beam reflected by the single mirror forms a predetermined angle in the auxiliary scanning direction. Further, the single mirror is formed to have a positive power both in the main scanning direction and in the auxiliary scanning direction, and a shape of the single mirror is asymmetric in the auxiliary scanning direction with respect to a reference line which extends in the main scanning direction and intersects an optical axis thereof.

Abstract: A scanning optical system includes a light source for emitting a beam of light and a first optical system that changes a cross-sectional shape of the beam into an oblong shape along a main scanning direction. A light deflector deflects the oblong cross-sectioned beam of light in the main scanning direction, and a second optical system receives a beam of light deflected by the light deflector for focusing the deflected beam of light onto a scanning surface. At least one surface of a lens in the first optical system is formed as a sub-scanning-plane aspherical surface so as to correct the spherical aberration of the scanning optical system in a sub-scanning direction caused by the second optical system.

Abstract: Disclosed is a diffractive optical element which includes a diffractive grating pattern on a base plate. The diffractive grating pattern includes a plurality of phase gratings arranged in parallel lines extending along a predetermined direction to cause diffraction of an incident beam. Each of the plurality of phase gratings has an asymmetrical phase pattern. There is a phase gap, .DELTA.P, representing a phase difference (in radians) between an end point and a beginning point of each phase pattern. The phase gap, .DELTA.P, is substantially equal for each of the plurality of phase gratings and satisfies the relationship0.7.pi.<.vertline..DELTA.P.vertline.<1.2 .pi..

Abstract: A cascade scanning optical system which includes: a first laser scanning optical system having a first polygon mirror, provided with a plurality of first reflecting surfaces, for deflecting a first scanning laser beam to scan a part of a scanning surface to generate a first scanning line; a second laser scanning optical system having a second polygon mirror, provided with a plurality of second reflecting surfaces, for deflecting a second scanning laser beam to scan another part of the scanning surface to generate a second scanning line, wherein the first and second laser scanning optical systems are arranged so as to align the first scanning line with the second scanning line at a point of contact therebetween in a main scanning direction to form a single scanning line; means for measuring a degree of tilt of each of the plurality of first reflecting surfaces and the plurality of second reflecting surfaces; and means for determining combinations of the plurality of first reflecting surfaces with the plurality

Abstract: A scanning optical system includes a light deflector and a light emitter which emits a beam of light which scans a scanning surface along a main scanning direction. The beam of light emitted by the emitter is incident onto the light deflector as a non-convergent beam of light in the main scanning direction. Further, an optical element which has a reflecting surface is utilized as an f.theta. element. The optical element includes a first surface onto which light from the light deflector is incident, and from which light transmitted through the optical element is emitted and a second surface which is provided with a reflective surface thereon. Further, at least the second surface of the optical element is shaped so as to have no rotational axis and to not be rotationally symmetrical about an optical axis. Additionally, at least one surface of the optical element is tilted with respect to an axis perpendicular to the beam of light incident thereon.

Abstract: A scanning optical system which includes a light source for emitting a beam of light, a light deflector for deflecting the beam of light in a main scanning direction, and a scanning lens which receives a beam of light deflected by the light deflector for focusing the deflected beam of light onto a scanning surface. The scanning lens includes a lens having a refractive index distribution in either the main or the sub-scanning direction.

Abstract: Disclosed is a scanning apparatus having a cascade scanning optical system.

Abstract: Disclosed is a scanning apparatus having a cascade scanning optical system.

Abstract: Disclosed is a scanning apparatus having a cascade scanning optical system.

Abstract: A scanning optical system for scanning an object surface includes a light emitting device for emitting a beam of light and a deflection mirror rotatable to deflect the beam emitted by the light emitting device, and to scan within a predetermined scanning angle zone along a main scanning plane. The beam incident to the deflection mirror is inclined in a direction of an auxiliary scanning, a direction of incidence of the beam onto the deflection mirror intersects a rotational axis of said deflection mirror, and the direction of the beam is orthogonal to a reflection surface of the deflection mirror, when viewed in the main scanning plane as the beam reaches the center of the predetermined scanning angle zone. A curved mirror having power at least in the main scanning plane, and a toric lens positioned between the curved mirror and the object surface and having power at least in the auxiliary scanning direction are also provided.

Abstract: A scanning optical system includes a light source for emitting a beam of light and a first optical system that changes a cross-sectional shape of the beam into an oblong shape along a main scanning direction. A light deflector deflects the oblong cross-sectioned beam of light in the main scanning direction, and a second optical system receives a beam of light deflected by the light deflector for focusing the deflected beam of light onto a scanning surface. At least one surface of a lens in the first optical system is formed as a sub-scanning-plane aspherical surface so as to correct the spherical aberration of the scanning optical system in a sub-scanning direction caused by the second optical system.

Abstract: A laser drawing apparatus is provided that splits a laser light into a plurality of drawing beams aligned in a common plane. The aligned drawing beams are reflected and deflected through a deflecting mirror to scan a drawing surface. The beams reflected off the mirror are converged through a scanning optical system onto the drawing surface in such a manner that the height of the drawing beams on the drawing surface is in proportion to the deflection angle and a strict relationship exists between the various incident and reflecting angles as well as the focal length of the scanning optical system and pitch of the drawing beams.

Abstract: A cascade scanning optical system which includes a plurality of laser scanning optical systems each emitting a laser beam to scan a surface of a member, and a beam splitter positioned in an optical path between the plurality of laser scanning optical systems and the member such that a first laser beam which has passed through the beam splitter and a second laser beam which has been reflected by the beam splitter proceed to the surface on a common line thereon in respective ranges of the common line. Each of the plurality of laser scanning optical systems is desinged as a telecentric system.

Abstract: An optical image forming device includes a scanning lens for scanning, in a main scanning direction, eight drawing beams on an image plane. A monitoring beam is scanned repeatedly and simultaneously with the drawing beams in a predetermined scanning range. The eight drawing beams are scanned such that drawing beams adjacent each other in a sub-scanning direction pass a same position in the scanning range on the image plane at a different time. The monitoring beam is scanned prior to scanning of the drawing beam. A scale clock generator is provided for generating scale clock signals identifying positions of the monitoring beam in the scanning range. A modulator modulates the eight drawing beams such that modulations for each of the drawing beams at a same position in the scanning range are synchronized with a timing of a same scale clock signal obtained by the scale clock generator.

Abstract: A cascade scanning optical system which includes: a pair of laser scanning optical systems each having a laser beam emitter and a laser beam deflector, wherein a laser beam emitted by the laser beam emitter enters the laser beam deflector so that the laser beam deflector deflects the laser beam to scan a surface of a member such that the laser beams proceed to the surface on a common line thereon in respective ranges of the common line; a pair of mirrors respectively provided in the pair of laser scanning optical systems, each of the pair of mirrors being positioned in a corresponding optical path between the laser beam deflector and the member to reflect a laser beam incident thereon toward the surface; a pair of cylindrical lenses having power in a sub-scanning direction, respectively provided in the pair of laser scanning optical systems, each of the pair of cylindrical lenses being positioned in a corresponding optical path between the laser beam emitter and the laser beam deflector; first means for adjus

Abstract: A cascade scanning optical system which includes a first laser scanning optical system for emitting a first laser beam to scan a surface of a member to generate a first scanning line, and a second laser scanning optical system for emitting a second laser beam to scan the surface to generate a second scanning line, wherein the first and second laser scanning optical systems are arranged so as to combine the first scanning line with the second scanning line at a point of contact therebetween in a main scanning direction to form a single scanning line, and wherein each of the first and second laser scanning optical systems is designed as a non-telecentric system through which the incident angle of a corresponding one of the first and second laser beams relative to the surface varies in accordance with a variation in the position of a scanning spot of the corresponding one of the first and second laser beams on the surface in the main scanning direction, and further wherein an incident angle of each of the first