JPH08190061A - Scanning optical device - Google Patents

Abstract

PURPOSE: To improve operability in the case of assembling optical parts and to reduce the number of parts so as to reduce cost by finishing at least a part of an optical housing as a mirror surface and using it as a reflection surface for laser beam scanning instead of a reflection mirror. CONSTITUTION: A polygon scanner 3 housing a laser light source and a polygon mirror 2 deflecting a laser beam and lenses 4 and 5 for condensing a luminous flux on a surface to be scanned are housed in the optical housing 1. The optical housing 1 constituted in such a way does not house the reflection mirror for laser beam scanning separately, but a part of the inner surface of the optical housing 1 is finished as the mirror surface and set as the laser beam reflection surface 6 for laser beam scanning instead of the reflection mirror. Therefore, the mirror and the parts for fixing the mirror such as a leaf spring, etc., in the conventional device are disused and the operability in the case of assembling the optical parts such as the lenses 4 and 5 in the optical housing 1 is improved and the cost is reduced because of the reduction of the parts.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a laser printer, a digital PPC copying machine and a facsimile, and more particularly to a scanning optical apparatus used in these apparatuses.

[0002]

2. Description of the Related Art A scanning optical device used in an image forming apparatus such as a laser printer includes a laser light source, a polygon scanner for deflecting laser light, and a polygon scanner.
A lens for condensing a light beam on a surface to be scanned and a reflection mirror for scanning a laser beam are housed and provided in an optical housing.

The structure of such an optical housing, especially the reflection mirror, has been improved in various ways as in the case of the polygon scanner and the like. For example, Japanese Laid-Open Patent Publication No. 5-45599.
As shown in Japanese Patent Laid-Open Publication No. 2003-242242, there has been proposed a structure in which a long mirror for scanning a laser beam made of synthetic resin is fixed at both ends by a U-shaped clamping spring having excellent elasticity.

However, in the structure shown in Japanese Patent Laid-Open No. 5-45599, one mirror is fixed by two leaf springs, so that the workability during assembly is poor and the number of parts is large.

The present invention has been made in view of such conventional problems, and it is possible to reduce the number of reflecting mirrors and the plate springs for fixing the reflecting mirrors, thereby improving workability when assembling optical components in an optical housing. In addition, it is an object of the present invention to provide a scanning optical device that can reduce costs by reducing the number of parts.

[0006]

According to the present invention, a laser light source, a polygon scanner for deflecting laser light, a lens for condensing a light beam on a surface to be scanned, and a reflection mirror for laser light scanning are provided in an optical housing. In the scanning optical device housed in the above, at least a part of the optical housing is mirror-finished so as to serve as a reflection surface for laser light scanning instead of the reflection mirror.

In the scanning optical device according to the present invention, at least a part of the optical housing is mirror-finished, and a mirror surface formed by aluminum vapor deposition on the inner surface of the optical housing is used as the reflection surface. You can

In the scanning optical device according to the present invention, instead of mirror-finishing at least a part of the optical housing, a metal sheet having a mirror-finished surface is adhered to the inner surface of the optical housing to serve as the reflecting surface. Can be configured.

In the scanning optical apparatus according to the present invention, instead of mirror-finishing at least a part of the optical housing, a resin sheet having a mirror-finished surface is adhered to the inner surface of the optical housing to serve as the reflecting surface. It can also be configured.

In the scanning optical device according to the present invention, the optical housing may be formed by injection molding a synthetic resin material.

[0011]

Embodiments of the scanning optical device according to the present invention will be described below with reference to the drawings. It should be noted that, although three embodiments will be described below, common portions in each embodiment will be denoted by common reference numerals, and overlapping description will be omitted.

FIG. 1 is a perspective view showing a first embodiment of a scanning optical device according to the present invention. In the figure, reference numeral 1 denotes an optical housing (only half is shown in the figure), a polygon scanner 3 for accommodating a laser light source (not shown), a polygon mirror 2 for deflecting the laser light, and a light beam is condensed on a surface to be scanned. It contains lenses 4 and 5 for making it work. The optical housing 1 of the present embodiment does not separately accommodate a reflection mirror for scanning a laser beam, but a part of the inner surface of the optical housing 1 is mirror-finished,
Laser light reflecting surface 6 for laser light scanning instead of a reflecting mirror
And For this reason, there is no need for conventional components such as a mirror and a leaf spring for fixing the mirror, and workability when assembling optical components such as the lenses 4 and 5 in the optical housing 1 is improved.

FIG. 2 is a perspective view showing a second embodiment of the scanning optical device according to the present invention, which is an optical housing 10 of this embodiment.
Is formed by injection-molding a synthetic resin material, and the laser light reflecting surface 11 is formed by vapor-depositing aluminum on a part of the optical housing 10.

FIG. 3 is a perspective view showing a third embodiment of the scanning optical apparatus according to the present invention, and an optical housing 15 of this embodiment.
A metal sheet 16 having a mirror surface is bonded to a part of the optical housing 15 to form a laser light reflecting surface.
Of course, a resin sheet having a mirror surface may be used.

[0015]

As described above, in the scanning optical device according to the present invention, a part of the optical housing itself is mirror-finished, or a mirror surface is formed on the inner surface of the optical housing by aluminum vapor deposition, or alternatively, the inner surface of the optical housing is formed. Since a reflecting mirror is made by adhering a metal sheet or resin sheet with a mirror surface on the surface, it is possible to reduce the number of separate mirrors and parts such as leaf springs that fix it to the optical housing, and improve the ease of assembly. This has the effect of reducing costs.

A scanning optical device according to claims 3 and 4,
Since the sheet whose surface is a mirror surface is adhered to the housing to form the reflection mirror, there is an effect that the labor of processing the reflection surface is saved, the manufacturability is further improved, and the cost can be reduced. Exclude.

In the scanning optical device according to the fifth aspect, since the optical housing is manufactured by injection molding of resin, there is an effect that it can be manufactured at a lower cost.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of a scanning optical device according to the present invention.

FIG. 2 is a perspective view showing a second embodiment of the scanning optical device according to the present invention.

FIG. 3 is a perspective view showing a third embodiment of the scanning optical device according to the present invention.

[Explanation of symbols]

 1 Optical Housing 2 Polygon Mirror 3 Polygon Scanner 4, 5 Lens 6 Laser Light Reflecting Surface 10 Optical Housing 11 Laser Light Reflecting Surface 15 Optical Housing 16 Metal Sheet

Claims (5)

[Claims] 1. A scanning optical device comprising a laser light source, a polygon scanner for deflecting laser light, a lens for converging a light beam on a surface to be scanned, and a reflection mirror for scanning the laser light, which are housed in an optical housing. In the application, at least a part of the optical housing is mirror-finished to serve as a reflecting surface for laser light scanning instead of the reflecting mirror. 2. The scanning optical system according to claim 1, wherein at least a part of the optical housing is mirror-finished, and a mirror surface formed by vapor deposition of aluminum on the inner surface of the optical housing is used as the reflecting surface. apparatus. 3. The reflection surface is formed by bonding a metal sheet having a mirror-finished surface to the inner surface of the optical housing, instead of mirror-finishing at least a part of the optical housing. Item 1. The scanning optical device of item 1. 4. A resin sheet having a mirror-finished surface instead of mirror-finishing at least a part of the optical housing is bonded to the inner surface of the optical housing to serve as the reflecting surface. Item 1. The scanning optical device of item 1. 5. The scanning optical device according to claim 1, wherein the optical housing is formed by injection molding a synthetic resin material.