Optical scanning apparatus

An optical scanning apparatus comprising:

• a light source for issuing an optical beam;
• a scanner, including at least first and second reflecting surfaces, for deflecting the optical beam issued from said light source;
• transfer optics by which the optical beam deflected by said first reflecting surface of said scanner is allowed to be incident on said second reflecting surface of said scanner;
• and
• scanning optics by which the optical beam deflected by said second reflecting surface of said scanner is allowed to be focused to form a beam spot on a surface to be scanned;
• wherein said transfer optics are arranged in such a way that images respectively corresponding to said first and second reflecting surfaces of the scanner are substantially conjugated to each other in the sub-scanning direction in terms of geometrical optics, and said optical beam incident on said first reflecting surface is converged near said first reflecting surface as an imaging point (P), said optical beam further forming an imaging point (Q) by means of said transfer optics to be located near said second reflecting surface between said second reflecting surface and said scanning optics.

An optical scanning apparatus comprising:

• a light source for issuing an optical beam;
• a scanner, including at least first and second reflecting surfaces, for deflecting the optical beam issued from said light source;
• transfer optics by which the optical beam deflected by said first reflecting surface of said scanner is allowed to be incident on said second reflecting surface of said scanner;
• and
• scanning optics by which the optical beam deflected by said second reflecting surface of said scanner is allowed to be focused to form a beam spot on a surface to be scanned;
• wherein said optical beam incident on said first reflecting surface is converged near said first reflecting surface as a first imaging point (P), said optical beam further forming an imaging point by means of said transfer optics to be located near said second reflecting surface between said second reflecting surface and a point (Q),
• wherein said point (Q) is an imaginary imaging point of said first imaging point (P) throughout an imaginary transfer optic having conjugate points at said first and second reflecting surfaces of the scanner in the sub-scanning direction.

An optical scanning apparatus comprising:

• a light source for issuing an optical beam;
• a scanner having at least first and second reflecting surfaces for deflecting the optical beam from said light source;
• transfer optics by which the optical beam deflected by said first reflecting surface of said scanner is allowed to be incident on said second reflecting surface of the scanner which is different from said first reflecting surface, with the thus deflected optical beam being focused to form a beam spot on a surface to be scanned, wherein the optical beam which has been deflected by reflection from said first reflecting surface of said scanner is passed through said transfer optics to be incident on said second reflecting surface at an angle in the sub-scanning direction;
• and
• scanning optics through which the optical beam deflected by reflection from said second reflecting surface is passed to form a beam spot on the surface to be scanned, said scanning optics being arranged such that images respectively corresponding to said second reflecting surface of the scanner and the surface to be scanned have a substantially conjugated relationship in the sub-scanning direction in terms of geometrical optics.

An optical scanning apparatus, comprising:

• a light source for emitting an optical beam;
• a rotating polygonal mirror with a plural number of reflecting surfaces for reflecting and deflecting said optical beam emitted from said light source;
• transfer optics for receiving the optical beam that is reflected and deflected by a first reflecting surface of said rotating polygonal mirror and transferring the optical beam to a second reflecting surface of said rotating polygonal mirror;
• and
• scanning optics for scanning a scanned surface with a beam spot formed on the scanned surface by the optical beam that is reflected and deflected by said second reflecting surface of said rotating polygonal mirror,
• wherein said first and second reflecting surfaces of said rotating polygonal mirror are oppositely disposed with respect to the rotating axis of said rotating polygonal mirror, and the optical beam emitted from said light source is incident on said first reflecting surface and is angled with respect to the optical axis, and
• wherein the optical beam transmitted by said transfer optics is incident on said second reflecting surface and is angled with respect to the optical axis, said transfer optics substantially conjugates images respectively corresponding to said first reflecting surface and said second reflecting surface in the sub-scanning direction, and said scanning optics substantially conjugates images respectively corresponding to said second reflecting surface and said scanned surface in the sub-scanning direction.

An optical scanning apparatus comprising:

• a light source for issuing an optical beam;
• a scanner, including at least first and second reflecting surfaces, for deflecting the optical beam issued from said light source;
• transfer optics by which the optical beam deflected by said first reflecting surface of said scanner is allowed to be incident on said second reflecting surface of said scanner;
• and
• scanning optics by which the optical beam deflected by said second reflecting surface of said scanner is allowed to be focused to form a beam spot on a surface to be scanned;
• wherein
• said scanning optics are arranged in such a way that images respectively corresponding to said second reflecting surface and said surface to be scanned are substantially conjugated to each other in the sub-scanning direction in terms of geometrical optics, and said optical beam incident on said first reflecting surface is converged near said first reflecting surface as an imaging point (P), said optical beam further forming an imaging point by means of said transfer optics to be located on said second reflecting surface.

An optical scanning apparatus comprising:

• a light source for issuing an optical beam;
• a scanner for deflecting said optical beam issued from said light source that is incident on a reflecting surface of said scanner at an angle in the sub-scanning direction;
• scanning optics, including an anamorphic lens, by which the optical beam deflected from said reflecting surface of said scanner is focused to form a beam spot on a surface to be scanned, wherein said anamorphic lens has a positive refractive power in the sub-scanning direction and, at either end of the scan range, the optical beam deflected by said reflecting surface of said scanner is incident on said anamorphic lens at a position spaced from the optical axis of said anamorphic lens in the sub-scanning direction, wherein the optical axis of said anamorphic lens is located between said position and a line normal to said reflecting surface in said sub-scanning direction;
• and
• a horizontal synchronous lens which is inclined by an angle about the optical axis of said horizontal synchronous lens.

An optical scanning apparatus comprising:

• a light source for issuing an optical beam;
• a scanner for deflecting said optical beam issued from said light source that is incident on a reflecting surface of said scanner at an angle in the sub-scanning direction;
• scanning optics, including an anamorphic lens, by which the optical beam deflected from said reflecting surface of said scanner is focused to form a beam spot on a surface to be scanned, wherein said anamorphic lens has a positive refractive power in the sub-scanning direction and, at either end of the scan range, the optical beam deflected by said reflecting surface of said scanner is incident on said anamorphic lens at a position spaced from the optical axis of said anamorphic lens in the sub-scanning direction, wherein the optical axis of said anamorphic lens is located between said position and a line normal to said reflecting surface in said sub-scanning direction;
• and
• a horizontal synchronous sensor which is inclined by an angle about the optical axis of said-horizontal synchronous sensor.

An optical scanning apparatus comprising:

• a light source for issuing an optical beam;
• a scanner for deflecting said optical beam issued from said light source that is incident on a reflecting surface of said scanner at an angle in the sub-scanning direction;
• scanning optics, including an anamorphic lens, by which the optical beam deflected from said reflecting surface of said scanner is focused to form a beam spot on a surface to be scanned, wherein said anamorphic lens has a negative refractive power in the sub-scanning direction and, at either end of the scan range, the optical beam deflected by said reflecting surface of said scanner passes through said anamorphic lens at a position spaced from the optical axis of said anamorphic lens in the sub-scanning direction and on a side of the optical axis of said anamorphic lens toward a line normal to said reflecting surface;
• and
• a horizontal synchronous lens which is inclined by an angle about the optical axis of said horizontal synchronous lens.

An optical scanning apparatus comprising:

• a light source for issuing an optical beam;
• a scanner for deflecting said optical beam issued from said light source that is incident on a reflecting surface of said scanner at an angle in the sub-scanning direction;
• scanning optics, including an anamorphic lens, by which the optical beam deflected from said reflecting surface of said scanner is focused to form a beam spot on a surface to be scanned, wherein said anamorphic lens has a negative refractive power in the sub-scanning direction and, at either end of the scan range, the optical beam deflected by said reflecting surface of said scanner passes through said anamorphic lens at a position spaced from the optical axis of said anamorphic lens in the sub-scanning direction and on a side of the optical axis of said anamorphic lens toward a line normal to said reflecting surface;
• and
• a horizontal synchronous sensor which is inclined by an angle about the optical axis of said horizontal synchronous sensor.