Canon Kabushiki Kaisha

Yoshihiro Ishibe

Hiroki Yoshida

Kazuo Fujibayashi

Koji Hoshi

Manabu Kato

Keiichiro Ishihara

Takahisa Kato

Kazumi Kimura

Susumu Yasuda

Yasuhiro Matsuo

Yuichi Tomioka

Kazuhiko Onuki

Akira Morisawa

Kentarou Nomura

Objects are to obtain a highly accurate diffraction element that may prevent an intensity decrease of a light beam entering a light receiving unit without a decrease in diffraction efficiency and without a problem of flare or the like, a manufacturing method for the diffraction element, and a spectrometer using the same. A diffraction element () includes a diffraction grating formed on a substrate having a curved surface. In the diffraction element (), the curved surface () has an anamorphic shape formed by pivoting a curved line (I) in a plane about a straight line (II) in the same plane serving as a rotation axis, and gratings () of the diffraction grating () exist in cross sections orthogonal to the rotation axis.

Diffraction element, manufacturing method for diffraction element, and spectrometer using the same

A multi-beam light scanning apparatus includes incident optical systems each of which allows a light beam to enter a deflection surface of a rotational polygon mirror in a sub scanning section from above and below directions obliquely with respect to a surface perpendicular to a rotation axis of the rotational polygon mirror at a finite angle, and a light source unit which is disposed for each of the incident optical systems and has light emitting portions. A light emitting portion corresponding to printing of a head line in the sub scanning direction among the light emitting portions of the light source unit that are disposed obliquely in the upward direction, and a light emitting portion corresponding to the printing of the head line in the sub scanning direction, that are disposed obliquely in the downward direction are different from each other in the sub scanning direction.

Multi-beam light scanning apparatus and image forming apparatus using the same

A multi-beam optical scanning device which enables uniform scan line pitch and high precision image, includes a light source having plural light emitting members, a rotary polygonal mirror having a deflecting surface, a first optical system for imaging a light beam on the deflecting surface and a second optical system for imaging the light beam on a scan surface to be scanned, wherein the optical axis of the first optical system is disposed at a particular angle in a sub-scan section with respect to a plane perpendicular to the deflection axis of the deflecting surface, and wherein, with respect to the imaging magnification in the sub-scan section of the second optical system on the optical axis and between the deflecting surface and the scan surface, the imaging magnification at a scan start side is made large while the imaging magnification at the scan end side is made small or, alternatively, the imaging magnification at a scan start side is made small while the imaging magnification at the scan end side is made large.

Multi-beam optical scanning device and image forming apparatus using the same

A laser light control device for an image forming apparatus designed to improve the auto power control (APC) accuracy and to reduce the control time. A multifunctional optical element has a plurality of different optical characteristics. A detecting unit is adapted to detect laser light from the semiconductor laser. A control unit is adapted to perform control of the write start position of the laser light in the main scanning direction and control of the quantity of the laser light by detecting the laser light by means of the detecting unit after passage of the laser light through the multifunctional optical element.

Laser light control device for image forming apparatus, and image forming apparatus

An optical scanning apparatus allowing reduction in the size of the overall apparatus and the size of an imaging optical system LB with the use of an optical deflector that swings back-and-forth and an image forming apparatus using such an optical scanning apparatus, comprising: light source means; a condense optical system that condenses a light beam emitted from the light source means; an optical deflector that deflects the light beam emergent from the condense optical system; and an imaging optical system that images the light beam deflected by a deflection surface of the optical deflector on a scanning surface, wherein the optical deflector has a function of moving the deflection surface back-and-forth, the light beam emergent from the condense optical system converges in a sub-scanning cross section, and the convergence position is on the light source side of the deflection surface.

Optical scanning apparatus and image forming apparatus using same

It is an object of the present invention to realize a multi-beam optical scanning device which is suitable for high speed and high recording density by almost completely offsetting and correcting a deviation of focusing positions in a main scanning direction of plural spots in an entire surface to be scanned without deteriorating focusing properties at all. The multi-beam optical scanning device includes: a light source devicehaving plural luminescence parts; a rotating polygon mirror; a first optical systemwhich converts plural light beams into convergent light beams or divergent light beams; and a third optical systemwhich guides the light beams onto a surface to be scannedof a drum shape, and when it is assumed that a maximum value of a positional deviation amount generated in a first direction is &#x3b4;Y, a maximum value of a positional deviation amount generated in a second direction is &#x3b4;Y, and a maximum value of a positional deviation amount generated in a third direction is &#x3b4;Y, conditional expression (1) is satisfied.

Multi-beam optical scanning device

An optical scanning device includes a rotary polygonal mirror, an input optical system for direct a light beam from a light source to a deflecting surface of the rotary polygonal mirror, and an imaging optical system for imaging the deflected light beam on a scan surface, wherein in a main scan section the light beam incident on the deflecting surface has a beam width wider than a width of the deflecting surface, wherein at least one optical surface of at least one imaging optical element of the imaging optical system has a shape in the sub-scan section which shape is a non-arcuate shape including an aspherical coefficient of quartic or higher order, and wherein the aspherical coefficient of quartic or higher order changes in the main-scan direction and from a scan central portion of the imaging optical element to a scan end portion of the imaging optical element.

Optical scanning device and image forming apparatus using the same

An optical scanning device having a deflector with an oscillating element wherein a relation 0.85&#x3c;(dY/d&#x3b8;)/(dY/d&#x3b8;)&#x3c;1.15 is satisfied throughout an effective scan region, where &#x3b8;is a deflection angle of the oscillating element as a light beam scans the center position Yof an effective scan region on a scan surface with respect to a main-scan direction, &#x3b8; is the deflection angle of the oscillating element as the light beam scans a scan position Y in the effective scan region with respect to the main-scan direction, dYis an amount of change at the center position Yon the scan surface with reference to an amount of change d&#x3b8;of the oscillating element at the deflection angle &#x3b8;, and dY is an amount of change at the scan position Y on the scan surface with reference to an amount of change d&#x3b8; of the oscillating element at the deflection angle &#x3b8;.

An optical scanning device includes a rotary polygonal mirror for scanningly deflecting light beams emitted from a light source device having light emitting members disposed spaced apart from each other in a main-scan direction. The optical scanning device further includes an input optical system by which, in a sub-scan section, light beams are incident on a deflecting surface of the rotary polygonal mirror in an oblique direction with respect to a normal to the deflecting surface, and an imaging optical system by which the light beams scanningly deflected by the rotary polygonal mirror are imaged on a surface to be scanned.

An optical scanning apparatus which is free from any deterioration of drawing performance and which can be miniaturized and simplified in overall configuration, and an image forming apparatus using the optical scanning apparatus are provided. The optical scanning apparatus includes: a light source unit; an incident optical system for guiding a light beam emitted from the light source unit to a deflecting unit; and an imaging optical system for guiding the light beam deflected by the deflecting unit onto a surface to be scanned. The incident optical system includes an anamorphic condenser lens having a refractive power in a main scanning cross section and a refractive power in a sub-scanning cross section which are different from each other, and the imaging optical system has a refractive power with which a deflective surface of the deflecting unit or a vicinity of the deflective surface and the surface to be scanned are made in conjugate relation with each other, and also satisfies a conditional expression.

Optical scanning apparatus and method for adjusting the same

An optical scanning system includes a deflecting device to scanningly deflect a light beam from a light source in a main scan direction, and an imaging optical system for imaging, upon a surface to be scanned, the light beam deflected by a deflecting surface of the deflecting device. First and second differences in wavefront aberration are respectively produced as a result of reflection by the deflecting surface and as a result of transmission through the imaging optical system. At least one optical surface inside the imaging optical system is non-arcuate in a main scan section, so as to assure that the first and second phase differences are made opposite to each other.

Optical scanning system and image forming apparatus using the same

An overfilled optical scanning apparatus has an incidence optical system for converging a light beam onto a deflection surface of a light deflector which has a plurality of deflection surfaces, and an imaging optical system for imaging the deflected light beam onto a surface to be scanned. The imaging optical system satisfies a relationship among its focal length in a main scanning direction, the distance in the main scanning section from the rear principal plane position to an imaging point of the converged light beam, angles in the main scanning section formed by the optical axis of the imaging optical system and the principal ray of the light beams incident on the light deflector, the unevenness of distances in the main scanning section from the rotation center of the light deflector, and the number of pixels per inch in the main scanning direction on the surface to be scanned.

Optical scanning apparatus and image forming apparatus using the same

To obtain an optical element capable of obtaining uniform anti reflection characteristics over the whole optical surface having a finite curvature of the optical element, a plurality of convex optical pieces having an anti reflection function are provided on a surface having the finite curvature of the optical element independently along a normal direction of the surface having the finite curvature of the optical element.

Optical element and optical scanning device using the same

Disclosed is an optical scanning system and an image forming apparatus using the same, which is designed to reduce the overall size of the system and to make uniform the light spot diameter in a sub-scan direction, inside an effective scan region, as well as to ensure high-speed production of high-quality images, wherein the optical scanning system includes a light source, a condensing optical system, a deflector and an imaging optical system having one or more optical elements, wherein, in at least one optical element of the optical elements, the curvature of the opposite surfaces thereof changes continuously, inside an effective region, from the optical axis toward the peripheral portion thereof so that the sign of the curvature is reversed at the middle, and wherein, when the curvature radius of the surface of that optical element facing the deflector side, at the optical axis and in the sub-scan sectional plane, is denoted by rlwhile the least quantity of an absolute value of the curvature radius of the surface facing the scan surface side in an effective region of the portion where the sign of the curvature radius is reversed is denoted by |r2|, the optical element satisfies a specific relation for them.

Growing community of inventors

Utsunomiya, Japan

Yoshihiro Ishibe