JPS61242161A - Scanning optical device - Google Patents

Abstract

PURPOSE:To eliminate the need for high accuracy in optical parts but ensure to have a sufficient positioning in image areas by performing a movement adjustment for a cylindrical reflector to be set between a polygon mirror and sensitive substances in both directions such as an optical axis as one direction and a direction to be orthogonal to scanning and optical axis directions as other direction. CONSTITUTION:This device consists of a frame 10 where a cylindrical reflector 3 and its support members as well as other adjustment members are stored; a cylindrical reflector support spring 11 which supports the cylindrical reflector 3 at the frame 10 so that the reflector 3 is movable towards the optical axis direction as well as the direction to be orthogonal to the optical axis and the scanning directions; an optical axis direction adjustment screw 12 where the cylindrical reflector 3 is fixed on the frame 10 by screws and makes the cylindrical reflector 3 move back and forth, on right and left according to extents of delivery; cylindrical reflector hoisting spring 13 which is held by the frame 10 and the cylindrical reflector 3 from the directions to be orthogonal to the adjusting screw 12 and will press towards the cylindrical reflector 3 and the non-scanning direction; non-scanning direction adjustment screw 14 which will press the cylindrical reflector 3 against the spring 13. Thus this device can carry out simple and high accurate adjustment works for a reference image area by using laser beams.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for easily positioning a light beam in order to accurately set the position of an image area without requiring high precision from optical components. The present invention relates to a scanning optical device.

(Prior Art) As a conventional scanning optical device, for example, FIG.
There is a multifaceted beam deflector 11 as shown in the figure, which serves as a beam deflector that deflects a light beam such as a laser beam modulated according to a recording signal from a semiconductor laser (not shown) or the like in a predetermined direction.
11, an F-θ lens 2 that corrects the scanning speed of the light beam deflected and scanned by the polygon mirror 1, a cylindrical reflecting mirror 3 that reflects the beam from the F-θ lens 2 to the photoreceptor 4, and It is composed of a photoreceptor 4 that is exposed to a reflected beam from a cylindrical reflecting mirror 3.

In the above configuration, a light beam modulated according to a recording signal is output from a semiconductor laser, etc., is reflected by the mirror surface of the polygon mirror 1 that rotates at a constant speed, and according to the rotation, the laser beam,
The beam is deflected. The laser beam exiting polygon mirror 1 is F
- After the scanning speed is corrected by the θ lens 2, the light reaches the surface of the photoreceptor 4 after being reflected by the cylindrical reflecting mirror 3.
The surface of the photoreceptor is exposed according to the recording signal.

Alternatively, this is combined with adjustment of magnification based on adjustment of the optical axis direction of the F-θ lenses.
As a result, the image areas shown in FIG. 6 are set from FIG. 3, which will be described later.

[Problem that the invention seeks to solve]

However, in conventional scanning optical devices, high precision is required for each optical component, which has the disadvantage of making the device expensive.

[Means and effects for solving the problems] The present invention has been made in view of the above, and aims to enable accurate positioning of the image area without requiring high precision from optical components. An object of the present invention is to provide a scanning optical device in which a cylindrical reflecting mirror set between a polygon mirror and a photoreceptor can be moved and adjusted in both directions perpendicular to the optical axis direction and the scanning direction and the optical axis direction.

〔Example〕

Hereinafter, the scanning optical device according to the present invention will be explained in detail.

1 and 2 show an embodiment of the present invention, in which a cylindrical tube i
-+ Housing 10 in which the mirror 3, support member, and adjustment member are stored
and a cylindrical reflecting mirror support spring 11 that supports the cylindrical reflecting mirror 3 movably in the optical axis direction and in directions orthogonal to each of the optical axis direction and the scanning direction, and is screwed and fixed to the housing 10. , an optical axis direction adjustment screw 12 that moves the cylindrical reflection mirror 3 in the front-rear direction (optical axis direction) according to the amount of its extension; a cylindrical reflector lifting spring 13 that presses the cylindrical reflector 3 in a non-scanning direction;
It is comprised of a non-scanning direction adjustment screw 14 that presses the cylindrical reflecting mirror 3 against the spring 13.

In the above configuration, the adjustment method will be explained based on the image area explanatory diagrams of FIGS. 3 to 5 and the adjustment explanatory diagrams of FIGS. 6 to 8.

First, if you want to obtain an image area like the solid line frame in FIG. 3 but the image area is like the dotted line frame, adjust each of the non-scanning direction adjustment screws 14 by the same amount of advance to obtain a cylindrical reflection. By moving the mirror 3 as shown in FIG. 8 (from the broken line position to the solid line position), a proper image can be obtained. If it moves too far downward, turn the screw 14 in the opposite direction to that described above.

Also, if it is tilted like the broken line frame in Figure 4,
By adjusting either one of the non-scanning direction adjustment screws 14, the image area shown in the solid line frame shown in FIG. 4 can be obtained.

Next, when the image area is reduced in the scanning direction as shown by the broken line frame in FIG.
By adjusting the extension of each of them, the cylindrical reflecting mirror 3 moves as shown in FIGS. 6 and 7, and an appropriate image area as shown by the solid line frame in FIG. 5 can be obtained. Note that if the image area is too enlarged, the cylindrical reflecting mirror 3 may be moved away from the F-θ lens 2, contrary to the above case.

〔Effect of the invention〕

As explained above, according to the scanning optical device of the present invention, since the cylindrical reflecting mirror can be moved and adjusted in both the optical axis direction and the direction orthogonal to the scanning direction and the optical axis direction, the reference image area by the laser beam can be adjusted. can be adjusted easily and with high precision, and does not require high precision from optical components.

[Brief explanation of the drawing]

1 and 2 are a plan view and a side view showing an embodiment of the present invention; FIGS. 3, 4, and 5 are explanatory diagrams showing image areas before and after adjustment; Figures 6, 7 and 8 are explanatory diagrams for adjusting the cylindrical reflector, Figures 9 and 10
The figures are a side view and a plan view showing an example of a conventional scanning optical device. Explanation of symbols 1・−・・・Polygon mirror, 2・−・−・・F−
θ lens, 3-...Cylindrical reflector, 4-----
-One photoreceptor, 10...--Housing, 11...--
--- Cylindrical reflecting mirror support spring, 12 --- Optical axis direction adjustment screw, 13 --- One cylindrical reflecting mirror lifting spring, 14 --- Non-scanning direction adjusting screw. Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 Figure 8 Figure 9 Figure 1O

Claims (1)

[Scope of Claims] A scanning optical device that polarizes a modulated light beam by a polygon mirror, and guides the light beam from the polygon mirror to the surface of a photoreceptor by a cylindrical reflector for exposure, comprising: A first positioning mechanism that moves the mirror in the optical axis direction of the beam; and a second positioning mechanism that moves the cylindrical mirror in a direction perpendicular to each of the scanning direction and the optical axis direction of the light beam. Characteristic scanning optical device.