Brother Kogyo Kabushiki-Kaisha

Nidek Co., Ltd.

Hidetaka Hoshino

Hitoshi Fujino

Yoshifumi Nakamura

Toshio Sakai

Kazuhiro Hayakawa

Junji Fujitani

Akihiro Hayashi

Yoshinobu Hosoi

Yutaka Hattori

Yuichiro Kanazawa

Hiroyuki Ominato

Noritsugu Nozawa

Yasuomi Jibu

Yoshito Hosoi

Tomoyuki Okamoto

A light deflector includes: a polygon mirror made of plastic and having a plurality of reflecting surfaces; a motor including a rotor and configured to rotate the polygon mirror; and a pressing member configured to press the polygon mirror toward the rotor in an axial direction of the motor. The polygon mirror has a first surface having a polygonal shape, and a second surface opposite to the first surface in the axial direction and having a polygonal shape. The second surface faces the rotor. The polygon mirror includes a plurality of first contact portions configured to be in contact with and pressed by the pressing member, and the first contact portions are provided on the first surface at positions equally distant from an axis of the motor between each of vertices of the first surface and the axis of the motor.

Light deflector and polygon mirror

In a scanning optical apparatus, an illumination optical system has a diffractive power &#x3c6;dM and a refractive power &#x3c6;nM in a main scanning direction, and a ratio &#x3c6;nM/&#x3c6;dM in the main scanning direction for a focal length fi in a range of 10-22 mm satisfies: g2(fi)&#x2264;&#x3c6;nM/&#x3c6;dM&#x2264;g1(fi), where A(Z)=(1.897&#xd7;10)Z+6744Z+0.5255, B(Z)=(2.964&#xd7;10)Z+5645Z+0.6494, C(Z)=(3.270&#xd7;10)Z+3589Z+0.5250, D(Z)=(5.016&#xd7;10)Z+4571Z+0.8139, g1(fi)=fi{D(Z)&#x2212;B(Z)}/12&#x2212;5D(Z)/6+11B(Z)/6,g2(fi)=fi{C(Z)&#x2212;D(Z)}/12&#x2212;5C(Z)/6+11A(Z)/6g2(fi)=fi{C(Z)&#x2212;A(Z)}/12&#x2212;5C(Z)/6+11A(Z)/6.

Scanning optical apparatus

A polygon mirror made of plastic is provided. The polygon mirror has a plurality of reflecting surfaces, a first surface intersecting the plurality of reflecting surfaces at a first side, a second surface intersecting the plurality of reflecting surfaces at a second side opposite to the first side, with a through hole provided to extend through the first surface and the second surface at a center of the polygon mirror. The polygon mirror includes a plurality of gate marks of injection molding. When viewed from an extending direction of the through hole, the gate marks are located on straight lines passing through the center and vertices of the first surface, and are rotationally symmetric with respect to the center.

Polygon mirror, image forming apparatus, and method for manufacturing a polygon mirror

A light deflector and an image forming apparatus including the light deflector are provided. The light deflector includes a polygon mirror made of plastic and a motor including a rotor. The rotor supports the polygon mirror and includes a base and a first protrusion protruding from the base toward the polygon mirror in an axial direction. The polygon mirror includes a main body having a plurality of reflecting surfaces, and a second protrusion protruding from the main body toward the base. The second protrusion has an end face and an inner face. The end face is in contact with the base in the axial direction, and the inner face is in contact with the first protrusion in a radial direction.

Light deflector

In a scanning optical apparatus including a light source, a light deflector having a reflecting surface, and a single scanning lens, a light flux deflected in a main scanning direction is focused on an image surface. The reflecting and image surfaces are conjugate to each other with respect to a sub scanning direction, Bmax&#xd7;Bmin&#x3e;0, and Dmax&#xd7;Dmin&#x3c;0 where Bmax and Bmin are a maximum value and a minimum value, respectively, of paraxial focal points, Dmax and Dmin are a maximum value and a minimum value, respectively, of midpoints of focal depth in the sub scanning plane, the values being determined with reference to the image surface, wherein the value of the image surface is 0 and the values on a farther-from-the-scanning-lens side behind the image surface have positive values.

Scanning optical apparatus, image forming apparatus and method for manufacturing a scanning lens

In a light deflector including a polygon mirror having a plurality of reflecting surfaces; and a motor configured to rotate the polygon mirror, each of the reflecting surfaces, which has leading and trailing edges with respect to a direction of rotation of the polygon mirror and a center between the two edges, is configured to curve with the center displaced with respect to a reference straight line passing through the two edges in a plane perpendicular to an axis of rotation of the polygon mirror, radially, to a first side under a non-operating state in which the motor is not in operation, and to a second side (opposite to the first side) under a first rotating state in which progress of deformation of each of the reflecting surfaces has converged after a lapse of a first period of time from a start of rotation of the motor.

Light deflector and image forming apparatus including a rotating polygon mirror having displaceable reflecting surfaces

In a scanning optical apparatus, an illumination optical system has a diffractive power &#x3c6;dM and a refractive power &#x3c6;nM in a main scanning direction, and a ratio &#x3c6;nM/&#x3c6;dM in the main scanning direction for a focal length fi in a range of 10-22 mm satisfies: g2(fi)&#x2266;&#x3c6;nM/&#x3c6;dM&#x2266;g1(fi), where A(Z)=(1.897&#xd7;10)Z+6744Z+0.5255, B(Z)=(2.964&#xd7;10)Z+5645Z+0.6494, C(Z)=(3.270&#xd7;10)Z+3589Z+0.5250, D(Z)=(5.016&#xd7;10)Z+4571Z+0.8139, g1(fi)=fi{D(Z)&#x2212;B(Z)}/12&#x2212;5D(Z)/6+11B(Z)/6, g2(fi)=fi{C(Z)&#x2212;D(Z)}/12&#x2212;5C(Z)/6+11A(Z)/6.

A scanning optical apparatus includes: a light source; a light deflector configured to deflect the light beam from the light source in a main scanning direction; an incident optical system disposed between the light source and the light deflector and configured to render the light beam from the light source nearly parallel in the main scanning direction and to converge the light beam in a sub-scanning direction to bring the light beam to a focus in proximity to the light deflector; and a scanning lens configured to focus the light beam deflected by the light deflector onto a target surface to form spot-like images. The incident optical system includes one or more lenses which provide at least one refracting surface and at least one diffraction surface, and &#x3c6;nS/&#x3c6;ds&#x3c;0 is satisfied, where &#x3c6;nS is a refractive power in the sub-scanning direction and &#x3c6;dS is a diffraction power in the sub-scanning direction.

In a scanning optical apparatus, an illumination optical system has a diffractive power &#x3c6;dM in a main scanning direction, a diffractive power &#x3c6;dS in a sub-scanning direction, a refractive power &#x3c6;nM in the main scanning direction, and a refractive power &#x3c6;nS in the sub-scanning direction. A ratio &#x3c6;nM/&#x3c6;dM in the main scanning direction for a focal length fi in a range of 10-30 mm satisfies: g2(fi)&#x2266;&#x3c6;nM/&#x3c6;dM&#x2266;g1(fi), where A(Z)=(3.532&#xd7;10)Z+3023Z+0.7010, B(Z)=(5.719&#xd7;10)Z+4169Z+0.7678, C(Z)=(1.727&#xd7;10)Z+3244Z+0.4217, D(Z)=(1.373&#xd7;10)Z+3232Z+1.224, g1(fi)=fi{D(Z)&#x2212;B(Z)}/20&#x2212;0.5D(Z)+1.5B(Z), g2(fi)=fi{C(Z)&#x2212;D(Z)}/20&#x2212;0.5C(Z)+1.5A(Z), and a ratio &#x3c6;nS/&#x3c6;dS in the sub-scanning direction satisfies: &#x3c6;nS/&#x3c6;dS&#x3c;1.3.

A projector which is configured to project an image by means of a projection light onto a surface approximately parallel, or a surface approximately perpendicular, to an installation surface. According to aspects of the disclosure, the projector may include a first reflecting surface which reflects the projection light toward the approximately parallel surface; a second reflecting surface which reflects the projection light toward the approximately perpendicular surface; and a reflecting surface switching section which can switchably place the first reflecting surface and the second reflecting surface in an optical path of the projection light.

Projector

An optometric apparatus for examining refractive power of an examinee's eye subjectively, capable of performing highly-precise examination. The apparatus has a test window through which a presented optotype is seen, a first spherical-power applying unit which applies spherical power to the eye by changing a combination of spherical lenses in the window, a cylindrical-power applying unit which applies cylindrical power to the eye by changing a relative angle of a cylindrical axis of cylindrical lenses in the window, a second spherical-power applying unit including a spherical lens for correction, an instruction unit which instructs examination spherical and cylindrical power, a power-determining unit which determines power applied by the power-applying units so that a difference between the instructed examination power, and resultant spherical and cylindrical power through conversion for a spectacles wearing reference position falls within a predetermined permissible difference, and a control unit which controls driving of the power-applying units.

Optometric apparatus

A fundus camera for photographing a fundus of an eye to be examined has a system having an objective lens and a diaphragm arranged in a position approximately conjugate with a pupil with respect to the lens, for observing and photographing the fundus via the lens and the diaphragm, an optical path bifurcating member which is arranged on an optical path between the lens and the diaphragm, a system for observing an anterior segment of the eye via the lens and the optical path bifurcating member, and a correction member, which is arranged on an optical path of the fundus observation/photographing optical system, for correcting a deviation of an optical axis of the fundus observation/photographing optical system caused by arrangement of the optical path bifurcating member.

Fundus camera

A visual function test apparatus for testing a visual function by presenting an optotype to an examinee's eye is disclosed. This apparatus includes a first half mirror disposed on a projection optical axis of light of the optotype; an illumination light source having a projection optical axis which is made substantially coaxial with the projection optical axis of the optotype light by the first half mirror; a concave mirror which reflects an illumination light from the illumination light source and the optotype light; a second half mirror disposed between the first half mirror and the concave mirror, the second half mirror reflecting the optotype light and the illumination light both reflected by the concave mirror toward the examinee's eye; and a control section which changes a ratio between a light quantity of the optotype light and a light quantity of the illumination light in accordance with a predetermined contrast ratio.

Growing community of inventors

Aichi, Japan

Hidetaka Hoshino