JPS6223844B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording device using a laser, and more particularly to an optical device for guiding focused light from an f-theta lens onto a photosensitive layer.

A laser recording device that uses a laser to write an image corresponding to an input signal on a photoreceptor is generally accurately positioned and fixed with respect to an optical axis set on a strong substrate 1, as shown in Figure 1. laser tube 2, optical modulator 3, beam expander 4,
It consists of writing optical members such as a rotating polygon mirror 5 and an f-θ lens 6, and image forming process members including a photosensitive drum 7 mounted on a separate machine frame.
A laser beam swept by a rotating polygon mirror 5 is directly irradiated onto a photoreceptor drum 7 via an f-theta lens 6.

However, in the mechanism described above, the f-θ lens 6
Since the optical path length from the optical unit board must be long, the device becomes unnecessarily large, and when adjusting the parallelism with the drum generatrix and the optical path length, the adjustment knob 1a etc. must be operated to adjust the optical unit board. The problem was that the entire system had to be moved, making the device complicated.

In view of the problems of such conventional devices, the present invention provides f.
- The purpose is to provide a reflector support device in a new laser recording device that enables miniaturization of the device and simplification of the adjustment mechanism by arranging an adjustable optical member between the θ lens and the photoreceptor layer. shall be.

Another object of the present invention is to provide a new device that can be easily handled afterward by maintaining the adjusted state.

Therefore, the details of the present invention will be explained below based on the inside.

FIG. 2 is a side view of an apparatus showing an embodiment of the present invention, and reference numeral 10 denotes a strong housing made of cast aluminum or the like, in which the above-mentioned optical unit, that is, the laser tube 2 and the laser An optical modulator 3 consisting of an acousto-optic modulation element or an electro-optic element that modulates the laser beam oscillated from the tube 2 according to an input signal, a beam expander 4 that adjusts the laser beam to an appropriate beam diameter, and a synchronous motor 5a. A rotating polygon mirror 5 is driven by a rotating polygon mirror 5 that rotates at a constant speed and sweeps the laser beam in the main scanning direction.
and focuses the laser beam from the rotating polygon mirror 5,
This is irradiated onto the surface of the photoreceptor drum 7 as a spot light that moves from one side to the other at the same speed f
- A θ lens, etc. is attached. Furthermore, a wall surface 11 is formed on the housing 10 in an upright position at a position that blocks the front of the f-θ lens 6.
Here, a slit hole 12 through which a laser beam swept in the main scanning direction can pass is bored in a direction perpendicular to the plane of the paper in FIG. 3) is precisely cut out, and a fixed mirror 20 is attached thereto to reflect the laser beam.

30 is an adjustment mirror which is a characteristic part of the present invention;
As shown in FIG. 2, the laser beam reflected by the fixed mirror 20 is received and transferred to the housing 1.
It has the function of leading to the surface of the photosensitive drum 7 through a slit hole 15 formed in the bottom surface 14 of the photoreceptor drum 7, and is adjustably attached to a holding frame to be described later. Reference numeral 31 shown in FIGS. 3 and 5 is a board for mounting this adjustment mirror, and it is mounted by screws 32 on a base surface 16 that is precisely cut at the adjustment mirror mounting position of the housing 10. A slit hole 32 through which the laser beam from the fixed mirror 20 passes is bored in its surface, and a cover 33 covering almost the entire surface of the adjustment mirror 30 is attached at intervals to its upper surface. are spring plungers for adjusting the adjustment mirror 30; one plunger 34S for adjusting the sub-scanning direction is attached to the center of one side of the cover 33, and two plungers for adjusting the main scanning direction are attached to both ends of the other side. It consists of plungers 34M and 34M, each of which has 3
The spring plunger 34 and the spring plunger 36 are configured to be screwed together with the adjustment female screw members 35 and to support the back surface of the adjustment mirror 30 by the nose 34b pressed by the coil spring 34a. The support rod is in contact with the front surface of the adjustment mirror 30 at a corresponding position, and the support frame 37 provided on the back surface of the substrate 31 and the spring receiver seat 3 on the support rod 36 are connected to each other.
The adjustment mirror 30 is supported by a coil spring 38 interposed between the mirrors 6a and 6a.

In this embodiment, when the base plate 31 is attached to the reference surface 16 of the housing 11 and the spring plunger 34 is moved back and forth, the adjustment mirror 30 whose surface is pressed by the support rod 36 can be moved back and forth by the spring plunger 34. Displaces with . Therefore, these three spring plungers 34S, 34M, 34M (fifth
If the adjustment mirror 30 moves in parallel by a distance corresponding to the amount of advance and retreat, f
- From θ lens 6 to fixed mirror 20 and adjustment mirror 3
The optical path length from 0 to the surface of the photoreceptor drum 7 is
By varying the length equivalent to twice this amount of movement,
Accurate spot light can be focused on the surface of the photoreceptor drum. Also, a sub-scanning direction adjustment plunger 34S located at the apex of these three
If only the (Fig. 5 A) is advanced or retreated, the adjustment mirror 3
0 by an amount corresponding to the amount of advance and retreat, the position of the spot light irradiated onto the surface of the photoreceptor drum 7 can be moved in the sub-scanning direction, that is, in the rotational direction of the photoreceptor drum 7. This operation can easily correct the positional deviation between the writing optical unit and the image forming unit caused by the above error or impact. Plunger, 34M
By adjusting (FIG. 5A), correction in the main scanning direction can be performed.

On the other hand, if it becomes necessary to remove the adjustment mirror 30 during maintenance and inspection, the adjustment state will be maintained as is by removing the adjustment mirror 30 along with the board 31 from the reference surface 16 of the housing 10. There is no need to readjust.

Note that although the above embodiment is configured to adjust the final mirror, that is, the mirror facing the photoreceptor, it is also possible to make the mirror facing the f-θ lens adjustable. It is also possible to miniaturize the device without changing the optical path length by disposing a single adjustable mirror between the optical path of the f-θ lens and the photoreceptor.

As described above, according to the present invention, at least one
is swept in the main scanning direction using two reflecting means,
Since the focused laser beam is reflected and guided onto the photoreceptor, the device can be made more compact. Moreover, this reflector is disposed between the substrate and the cover member, and one side of the reflector is supported by an elastic support member on the substrate, while the other side is provided at the center of one side of the cover member in the sub-scanning direction. Since it is supported by the adjustment means and the two main scanning direction adjustment means provided at both ends of the other side, the elastic support member absorbs shocks and reduces the relative misalignment between the writing optical unit and the image forming unit. At the same time, by operating the sub-scanning direction adjusting means provided at the center of one side of the cover member, the reflector is adjusted in the sub-scanning direction using the main scanning direction adjusting means provided at both ends of the other side as a fulcrum; By operating either one of the main scanning direction adjustment means, this reflector, which is long in the main scanning direction, can be adjusted in the main scanning direction, making it possible to greatly simplify the adjustment mechanism. Since the adjusted state of the reflecting means can be maintained on the holding means, there is no need for readjustment upon attachment and detachment, and the adjustment operation can be significantly facilitated.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an outline of a general laser recording device, FIG. 2 is a side view showing a cross section of an example of a laser recording device to which the present invention is applied, and FIG. 3 is a perspective view showing an outline of a general laser recording device. Sectional view of the device showing one embodiment, No. 4
The figure is an enlarged view of the main parts of the above device, and FIGS. 5A and 5B are perspective views of the same device as seen from the top (back) and bottom (reflection surface) directions, respectively. 2... Laser tube, 3... Optical modulator, 4... Beam expander, 5... Rotating polygon mirror, 6... F-θ lens, 7... Photosensitive drum, 10... Housing, 1
3, 16...Reference surface, 20...Fixed mirror, 30...Adjustment mirror, 31...Substrate, 34...Spring plunger, 36...Support rod.

Claims (1)

[Claims] 1. Between a substrate having a slit hole in the main scanning direction and mounted on the support means of the writing optical system member, and a cover member fixed to the substrate at a distance,
A long reflector is provided in the main scanning direction to guide the laser beam onto the photoreceptor, and one surface of the reflector is supported by three elastic support members provided at the center of one side of the substrate and at both ends of the other side. In addition, one sub-scanning direction adjusting means is provided at the center of one side of the cover member corresponding to the elastic support member, and two sub-scanning direction adjusting means are provided at both ends of the other side.
A reflector support device in a laser recording apparatus, wherein the other surface of the reflector is supported by main scanning direction adjusting means.