Light scanning device having reduced size and parts count, and image forming apparatus with the same

Patent metadata

Field	Value
Publication number	US-9323050-B2
Application number	US-201314433432-A
Country	US
Kind code	B2
Filing date	Oct 15, 2013
Priority date	Oct 17, 2012
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

Respective first semiconductor lasers 44 a and 44 b and respective second semiconductor lasers 45 a and 45 b are arranged on a drive substrate 46 (YZ plane) such that the emission directions of light beams L 1 to L 4 of the respective first semiconductor lasers 44 a and 44 b and the respective second semiconductor lasers 45 a and 45 b are perpendicular to the YZ plane. On the YZ plane, the respective first semiconductor lasers 44 a and 44 b and the respective second semiconductor lasers 45 a and 45 b are divided to two mutually different lines y 1 and y 2 in the lateral direction perpendicular to the rotation axis of a polygonal mirror 42 , and the respective first semiconductor lasers 44 a and 44 b and the respective second semiconductor lasers 45 a and 45 b are arranged on respective different lines z 1 to z 4 in the vertical direction as the rotation axis direction of the polygonal mirror 42.

First claim

The invention claimed is:

1. A light scanning device, comprising:
a plurality of first light-emitting elements and a plurality of second light-emitting elements;
a deflecting section configured to deflect respective light beams emitted from the respective first light-emitting elements and the respective second light-emitting elements;
a first image-forming optical system configured to guide the respective light beams emitted from the respective first light-emitting elements and deflected by the deflecting section, to respective scan objects; and
a second image-forming optical system configured to guide the respective light beams emitted from the respective second light-emitting elements and deflected by the deflecting section, to respective scan objects, wherein
the respective first light-emitting elements and the first image-forming optical system, and the respective second light-emitting elements and the second image-forming optical system are divided to both sides of a straight line passing through a rotation axis of the deflecting section,
the light scanning device further comprises:
a first incident optical system configured to guide the light beams of the respective first light-emitting elements to a first incident spot of the deflecting section through an identical line in a view along a rotation axis direction of the deflecting section; and
a second incident optical system configured to guide the light beams of the respective second light-emitting elements to a second incident spot of the deflecting section through another identical line in a view along the rotation axis direction of the deflecting section,

the respective first light-emitting elements and the respective second light-emitting elements are arranged on an identical plane on a housing of the light scanning device such that emission directions of the light beams of the respective first light-emitting elements and the respective second light-emitting elements are perpendicular to the plane,
on the plane, the respective first light-emitting elements and the respective second light-emitting elements are divided to two mutually different lines in a lateral direction perpendicular to the rotation axis of the deflecting section, and all of the respective first light-emitting elements and the respective second light-emitting elements are arranged on different lines in a vertical direction corresponding to the rotation axis direction of the deflecting section, and
a line pitch in the vertical direction between the two mutually different lines in the lateral direction is narrower than respective outer diameters of the first light-emitting elements and the second light-emitting elements.

2. The light scanning device according to claim 1 , wherein
the line pitch in the vertical direction is equal to or shorter than a line pitch in the lateral direction.

3. The light scanning device according to claim 1 , wherein
the respective first light-emitting elements and the respective second light-emitting elements are arranged at respective corners of a trapezoidal on the plane.

4. The light scanning device according to claim 1 , wherein
the respective first light-emitting elements and the respective second light-emitting elements are arranged at respective corners of a saw-tooth shape on the plane.

5. An image forming apparatus, comprising
the light scanning device according to claim 1 , wherein
the image forming apparatus forms a latent image on a scan object by the light scanning device, develops the latent image on the scan object as a visible image, and transfers and forms the visible image from the scan object to a paper sheet.

Assignees

• Sharp Kk

Inventors

• Matsuo Manabu
• Shirai Nobuhiro

Classifications

• G03G15/0409

  Details of projection optics (for projection printing apparatus G03B27/522) · CPC title

• H04N2201/04732

  Detecting at infrequent intervals, e.g. once or twice per line for main-scan control · CPC title

• H04N1/053

  in main scanning direction, e.g. synchronisation of line start or picture elements in a line · CPC title

• H04N2201/04744

  by detecting the scanned beam or a reference beam · CPC title

• H04N2201/0082

  Image hardcopy reproducer (H04N2201/0091 - H04N2201/0094 take precedence) · CPC title