JP2787818B2 - Optical box with built-in light source holder for light beam scanner - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage box (hereinafter referred to as an optical box) having a light source holder such as a laser generator used for a light beam scanning device such as a laser beam printer. Things.

[Prior Art] FIG. 6 shows a conventional example, and this configuration will be described according to an assembling procedure.

First, a laser chip 103 that emits a laser beam,
Between the laser emission driver 101 and the laser base 104,
The wave washer 102 is sandwiched and fixed. Next, a holder 105 having a built-in lens barrel 106 bonded and fixed to a collimator lens 107 is temporarily narrowed and fixed to the laser base 104.

Subsequently, the laser base 104 is moved and finally fixed so that the laser chip 103 emits laser light along the optical axis of the collimator lens 107. Then, after adjusting the distance between the collimator lens 107 and the laser chip 103 so that the laser light emitted from the collimator lens 107 becomes parallel light, the adhesive is flowed through the hole 113 provided in the holder 105. The collimator lens 107 is fixed.

Thus, a laser unit as one light source unit is configured.

Next, an fθ lens (not shown), a rotating polygon mirror (polygon) 110 for deflecting laser light, and motor unit components (stator coils and rotor bearings) 111 and 112 for rotating the polygon 110 are built in. The above laser unit is mounted on the optical box 108 which is located. Then, after adjusting the position of the cylindrical lens 109 in the optical axis direction so that the laser light is condensed at a position corresponding to the surface of the photosensitive drum with a good beam shape and light amount, the cylindrical lens 109 is fixed with an adhesive or the like. .

The polygon scanner unit is configured by the above steps.

[Problems to be Solved by the Invention] However, in the above-described conventional example, after the laser unit is manufactured and attached to the optical box 108, and then the polygon scanner unit is manufactured, there are the following disadvantages.

(1) A long working time was required because the laser unit and the scanner unit were manufactured in separate processes, and then both were attached and adjusted.

(2) The cost is high because the configuration is complicated.

(3) Position accuracy is difficult to obtain due to the large number of parts.

Therefore, an object of the present invention is to provide an optical box having a light source holder built therein in view of the above problems.

[Means for Solving the Problems] In the present invention for achieving the above object, an optical system unit such as a laser unit in which a light source such as a laser chip, an outer cylinder for fixing the light source, and a holder containing a collimator lens are integrated. Is attached to an optical box made of synthetic resin or the like, and the holder is built in the optical box. Also,
A window such as a hole through which a light beam can pass is provided at a position where the light emitted from the light source proceeds as it is and intersects the optical box.

The holder may be insert-molded into the optical box, or may be integrally formed at the same time as the optical box is molded.

Since the optical box has such a configuration, it is possible to adjust the light flux from the collimator lens to be parallel light and to adjust the position of the silicon lens without moving the optical box from the jig once fixed. The above problems can be solved.

Embodiment FIG. 1, FIG. 2, and FIG. 3 are views showing a first embodiment of the present invention.

In FIG. 1, which is a side sectional view showing the main body configuration of the polygon scanner unit, 1 is a laser driver for emitting a laser chip 3 as a light source, 2 is a wave washer for holding down the laser chip 3, and 4 is a laser chip 3.
5 is an outer cylinder or holder insert-molded when forming a synthetic resin storage box or optical box 6, 7 is a cylindrical lens, 8 is a polygon mirror for deflecting laser light. , 9 is polygon 8
A motor unit for turning the laser beam; 10 is a hole provided so that the laser beam passes through the optical box 6 when emitted straight without deflecting the laser beam; It is a collimator lens for turning light.

In the first embodiment, the adjustment of the laser beam is performed in the following procedure.

First, the laser light emitted from the laser chip 3 as a laser light source is collimated by the collimator lens 14 so as to become parallel light. Then, the cylindrical lens 7 is moved and adjusted so as to obtain a good beam spot diameter on the photosensitive drum surface.

This adjustment will be described in detail with reference to FIGS. Second example showing how to adjust the laser chip 3 and the collimator lens 14
In the figure, first, a laser chip 3, a wave washer 2, and a laser emission drive 1 are temporarily fixed to an optical box 6 with a built-in holder 5 by a set screw or the like. Next, the optical box 6 is fixed to a predetermined position of a jig (not shown), and a collimator lens is fixed.
The laser beam emitted from 14 is transmitted through the hole 10 of the optical box 6, the condenser lens 11 having a known focal length, and the objective lens 12.
The camera 13 is guided to a D camera 13, and the camera 13 is used to measure how the collimator lens 14 is currently associated with the laser chip 3. By this measurement, the position of the laser chip 3 and the like is adjusted and fixed so that the light from the collimator lens 14 becomes parallel light.

At this time, the hole 10 is required, and since the hole 10 is provided, the laser light from the collimator lens 14 can be measured with the laser chip 3 attached to the optical box 6, so that the light source and the light source can be fixed. It is not necessary to perform the above-described collimation adjustment when an optical system unit, ie, a laser unit, which is formed by integrating a cylinder and a holder containing a collimator lens in a separate process.

Next, the adjustment of the cylindrical lens 7 will be described with reference to FIG.

After the above adjustment of the collimator lens 14, fθ
Toric lens 22 and spherical lens 23, polygon 8, cylindrical lens 7, and horizontal synchronization signal (BD) forming a lens
All other components such as the detection mirror 27 and the optical fiber 28 are attached. At this time, it is unnecessary to remove and transfer the optical box 6 fixed to the jig to another jig for adjusting the cylindrical lens.

Next, the objective lens 24 and the CCD camera 25 are mounted at predetermined positions so that a beam spot at a position corresponding to the photosensitive drum 21 can be measured. Then, the cylindrical lens 7 is moved in the optical axis direction so as to obtain a good beam spot on the surface of the photosensitive drum 21, and after the adjustment, the cylindrical lens 7 is fixed with an adhesive or the like.

Finally, a lid or the like is attached to the hole 10 and the polygon scanner unit to seal them, thereby completing the polygon scanner unit.

As described above, in the first embodiment, the holder 5 is built in the optical box 6 and the hole 10 is formed at a position where the laser beam hits the optical box during laser emission. It is not necessary to move the optical box to another jig for each adjustment of the collimator lens 14 and the cylindrical lens 7.

FIG. 4 is a view for explaining the second embodiment. Those denoted by the same reference numerals as those in FIG. 1 indicate the same parts.

In the second embodiment, in the polygon scanner unit in which the R (curvature radius) of the collimator lens 34 is large and the optical path length is short, even if the collimating action of the collimator lens 34 is slightly shifted due to an environmental change, the beam spot on the photosensitive drum surface is reduced. Has little effect on That is, in the second embodiment, the holder of the collimator lens 34 is formed integrally with the resin of the optical box 36.
The adjustment in the second embodiment is performed as follows.

After molding the optical box 36, put the laser base 4, laser chip 3, wave washer 2, and laser driver 1 in the optical box.
Temporarily fix it to 36, insert the collimator lens 34 into the optical box 36,
After the collimation adjustment, the laser chip 3, the collimator lens 34, and the like are fixed to the optical box 36 by the main squeezing and the adhesive. Then, after attaching the motor unit 9, polygon 8, cylindrical lens 7, fθ lens, etc. to the optical box 36, the cylindrical lens 7 is moved back and forth in the optical axis direction so that the beam has a minimum spot shape on the photosensitive drum surface. Is adjusted, and the cylindrical lens 7 is fixed.

Also in the second embodiment, as in the first embodiment, the assembling adjustment of the polygon scanner unit at the time of assembly can be completed without moving the optical box 36, and the assembly can be simplified.
In addition, in the second embodiment, since the slide portion 36a of the optical box 36 for the collimator lens 34 is made of a synthetic resin, the cost can be further reduced.

FIG. 5 shows a third embodiment. 5, the same reference numerals as those in FIG. 1 denote the same parts.

In the third embodiment, a hole 10 provided in the optical box 6 is lowered by its own weight, and a self-weight shutter 15 that seals the hole 10 is closed.
Is provided.

When the collimator lens 14 and the cylindrical lens 7 are adjusted, the shutter 15 is rotated upward with the point A as a pivot so that the notch 15a of the shutter 15 and the pin at the point B are hooked, and the hole 10 is opened. Leave open (indicated by the dashed line in FIG. 5 (b)).

After the adjustment is completed, remove the notch 15a from the pin at point B,
The shutter 15 is lowered by its own weight and the hole 10 is closed.

This facilitated opening and closing of the hole 10, and facilitated assembly of the polygon scanner unit. The shutter or lid is not limited to the self-weight shutter described above, but may be provided with an openable / closable member integrally formed with the optical box.
It is sufficient that the hole 10 is opened and the hole 10 is closed after the adjustment.

[Effects of the Invention] As described above, according to the present invention, since the light source holder is incorporated at the same time when the optical box is formed, a hole or the like may be provided at a position corresponding to the optical box in the beam emission direction from the light source. For example, all adjustments can be made without moving the optical box, thereby simplifying the assembly. In addition, a holder as a light source unit is not required, and cost can be reduced.

Further, the number of components is reduced, and the positional accuracy of the scanner unit can be improved.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a first embodiment of the present invention, FIG. 2 is a sectional view for explaining laser beam adjustment in the first embodiment,
FIG. 3 is a top view for explaining the position adjustment of the cylindrical lens in the first embodiment, FIG. 4 is a side sectional view showing a second embodiment of the present invention, and FIG. 5 (a) is a third embodiment of the present invention. FIG. 5B is a side sectional view showing an example, FIG. 5B is a view showing an opening and closing operation of a shutter, and FIG. 6 is a sectional view showing a conventional example. 1 ... Laser driver, 3 ... Laser chip,
4 Laser base, 5 Holder, 6, 36 Optical box, 7 Cylindrical lens, 8 Polygon, 9
…… Motor unit, 10… Hole, 14, 34 …… Collimator lens, 15… Shutter, 22 …… Toric lens,
23 …… Spherical lens

Claims (5)

(57) [Claims] 1. An optical box of a light beam scanning device for mounting an optical system unit in which a light source, an outer cylinder for fixing the light source and a holder containing a collimator lens are integrated, wherein the holder is built in the optical box. An optical box with a built-in light source holder. 2. The optical box according to claim 1, wherein said optical box is made of a synthetic resin. 3. The optical box according to claim 1, wherein a window through which the light beam passes is provided at a position where the light beam from the light source intersects the optical box. 4. The optical box according to claim 2, wherein the holder is insert-molded in the optical box. 5. The optical box according to claim 2, wherein the holder is formed integrally with the optical box.