JPH1144857A - Light deflecting scanner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the production cost of a light deflecting scanner. SOLUTION: A 2nd optical box 22 is fixed on the side of a 1st optical box 21 and a photoreceptor drum 23 is arranged under the 2nd optical box 22. A laser unit 24 emitting a laser beam is attached to the 1st optical box 21, and the laser unit 24 is constituted of a semiconductor laser output device 31 emitting the laser beam, an electric substrate 32 on which an electric circuit controlling the device 31 is mounted, and a collimator lens 33 changing the laser beam from the device 31 into nearly parallel luminous fluxes. When relative positions of a reflecting mirror 40 and the drum 23 are changed, principal parts 31 to 39 mounted in the optical box 21 are used as they are and only the constitution of the optical box 22 is changed, so that the increase of the production cost is restrained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light deflection scanning device used for a laser printer, a laser facsimile, and the like.

[0002]

2. Description of the Related Art In a conventional light deflection scanning apparatus of this type, a laser unit 2 for emitting laser light is attached to an optical box 1 as shown in FIGS.
The laser unit 2 includes an electric board 3, a semiconductor laser output device 4, and a collimator lens 5. Inside the optical box 1, a cylindrical lens 6 and a rotary polygon mirror 7 are sequentially arranged, and the rotary polygon mirror 7 is supported by a drive motor 8.

In the traveling direction of the laser light deflected by the rotary polygon mirror 7, an fθ lens 9 and a folding mirror 10 are arranged. Further, a light detection mirror 11 for reflecting a part of the laser light from the rotary polygon mirror 7 and a light detection sensor 12 for detecting the laser light from the light detection mirror 11
And are arranged. A photosensitive drum 13 on which light from the folding mirror 10 is incident is disposed outside the optical box 1.

The laser light emitted from the laser output device 4 passes through a collimator lens 5 to become a substantially parallel light beam, passes through a cylindrical lens 6, enters a rotary polygon mirror 7, and forms a substantially linear image on a reflection surface 7a. I do. Rotating polygon mirror 7
Is rotated in the direction A by the driving force of the drive motor 8, so that the laser light deflected and scanned by the reflection surface 7a is
An image is formed on the photosensitive surface of the photosensitive drum 13 via the turning mirror 10.

[0005]

However, in the above conventional example, the optical box 1 is often a high-precision plastic molded product, and the folding mirror 10 is fixed to the mirror receiving portions 1a and 1b of the optical box 1. Therefore, the relative position between the optical box 1 and the photosensitive drum 13 changes, and the turning mirror 10
When changing the direction of the reflection surface of the mirror receiving portion 1a,
It is necessary to create a new optical box 1 in which the angle of 1b is changed. Creating a new optical box 1 has a problem of increasing capital investment, that is, manufacturing cost.

An object of the present invention is to provide an optical deflection scanning device which can solve the above-mentioned problems and can reduce the manufacturing cost.

[0007]

According to the present invention, there is provided a light deflection scanning apparatus for generating a light beam, and a first optical element for converting the light beam from the light source into a substantially parallel light beam. A second optical element that linearly images the light beam from the first optical element, a rotary polygon mirror that deflects and scans the light beam from the second optical element, and rotationally drives the rotary polygon mirror Driving means, a third optical element for forming a light beam from the rotary polygon mirror into a spot on the photosensitive member, and a synchronous signal detecting means for obtaining a synchronous signal of an image writing position on the photosensitive member. An optical deflection scanning device provided in a first optical box, wherein a reflecting means for reflecting a light beam from the third optical element to the photoreceptor is provided in a second optical box. A coupling means for integrally fixing the second optical box is provided.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the embodiments shown in FIGS. FIG. 1 is a plan view of the first embodiment, and FIG. 2 is a longitudinal sectional view. A second optical box 22 is fixed to the side of the first optical box 21, and the second optical box 22 is located below the second optical box 22. A photosensitive drum 23 is provided. First optical box 2
A laser unit 24 for emitting laser light is attached to 1. The laser unit 24 includes a semiconductor laser output device 31 for emitting laser light, and an electric board 32 on which an electric circuit for controlling the laser output device 31 is mounted. And a collimator lens 33 that converts the laser light from the laser output device 31 into a substantially parallel light beam.

A cylindrical lens 34 and a rotary polygon mirror 35 are sequentially arranged in the traveling direction of the laser beam from the collimator lens 33 inside the first optical box 21. The rotary polygon mirror 35 is supported by a drive motor 36 and is driven to rotate in the direction B.
The fθ lens 37 is arranged in the traveling direction of the laser beam deflected and scanned by the reflection surface 35a. A mirror 38 for light detection is arranged in the traveling direction of the laser light passing through the end of the fθ lens 37, and a sensor 39 for light detection is arranged in the traveling direction of the laser light reflected by the mirror 38 for light detection. ing. Then, the electric signal from the light detection sensor 39 is guided to control means (not shown),
The scanning start position of the image recording formed on the image is adjusted by the control means.

Here, a folding mirror 40 is integrally fixed to the second optical box 22 via mirror receiving portions 41 and 42 on both sides. The laser light from the fθ lens 37 passes through the window 21a formed in the first optical box 21 and the window 22a formed in the second optical box 22, and enters the turning mirror 40. I have. Second optical box 2
2 includes a window 22b for passing the laser beam reflected by the folding mirror 40 toward the photosensitive drum 23, and two brackets 43 and 44 for fixing the second optical box 22 to the first optical box 21. Are provided, and these brackets 4
Slots 3 and 44 have slots 4 for inserting screws 45 and 46.
3a and 44a are formed. The second optical box 22 configured as described above is screwed into the first optical box 13 after being adjusted via the long holes 43a and 44b so that the laser beam enters a predetermined position on the photosensitive drum 23. 45 and 46 are fixed.

The laser light emitted from the laser output device 31 passes through a collimator lens 33 to become a substantially parallel light beam, passes through a cylindrical lens 34, and directly enters a reflection surface 35a of a rotary polygon mirror 35 in the main scanning direction. In the sub-scanning direction, the light is converged, enters the reflection surface 35a, and forms a substantially linear image. Since the rotating polygon mirror 35 is rotated in the B direction by the driving force of the driving motor 36, the reflecting surface 35a
The laser beam deflected and scanned by the fθ lens 37 and the window 2
The light passes through 1a and 22a, is reflected by the turning mirror 40, and forms an image on the photosensitive surface of the photosensitive drum 23 through the window 22b. The laser light incident on the photosensitive drum 23 forms an electrostatic latent image in the main scanning direction by the rotation of the rotating polygon mirror 35 and in the sub-scanning direction by the rotation of the photosensitive drum 23.

A part of the laser light that has passed through the end of the fθ lens 37 is reflected by a light detection mirror 38 and enters a light detection sensor 39. The laser light incident on the light detection sensor 39 is incident on a control unit (not shown) as an electric signal, and the control unit adjusts a scanning start position of an image formed on the photosensitive drum 23.

In the first embodiment, the folding mirror 40
When the relative position between the first optical box 21 and the photosensitive drum 23 changes, the main components 31 to 39 mounted on the first optical box 21 are used as they are, and only the configuration of the second optical box 22 is changed. An increase in cost can be suppressed.

FIG. 3 is a plan view of the second embodiment, and FIG. 4 is a longitudinal sectional view of the photosensitive drum 23 above the second optical box 51.
Are provided, the second optical box 51 has the window 22b of the first embodiment omitted, and mirror receiving portions 52, 53 opposite to the first embodiment are formed. Further, brackets 43 and 44 similar to those of the first embodiment are provided. The second embodiment can achieve the same effects as the first embodiment. FIG. 5 is a plan view of the third embodiment, and FIG.
Is a longitudinal sectional view, in which the second optical box 22 having the folding mirror 40 of the first embodiment is omitted, and the photosensitive drum 23 is arranged at a position where the laser beam from the fθ lens 37 is directly incident. . In the third embodiment, since the folding mirror 23 of the first embodiment is not required, the manufacturing cost can be further reduced.

[0015]

As described above, in the light deflection scanning apparatus according to the present invention, the optical box, which is a component, is made up of the first optical box and the second optical box.
The main optical member is arranged in the first optical box, the folding mirror is arranged in the second optical box, and the configuration of the second optical box and the folding mirror is changed as necessary. First
By using only the optical box, the first optical box and the main components mounted on the first optical box can be used as they are even when the irradiation direction of the laser beam is different, so that the mold and the like can be used. It is suitable for small lots at low cost with reduced capital investment.

[Brief description of the drawings]

FIG. 1 is a plan view of a first embodiment.

FIG. 2 is a longitudinal sectional view.

FIG. 3 is a plan view of a second embodiment.

FIG. 4 is a longitudinal sectional view.

FIG. 5 is a plan view of a third embodiment.

FIG. 6 is a longitudinal sectional view.

FIG. 7 is a plan view of a conventional example.

FIG. 8 is a longitudinal sectional view of a conventional example.

[Explanation of symbols]

 Reference Signs List 21 first optical unit 22 second optical unit 23 photosensitive drum 24 laser unit 35 rotating polygon mirror 37 fθ lens 40 folding mirror

Claims (2)

[Claims] A light source for generating a light beam; a first optical element for converting the light beam from the light source into a substantially parallel light beam; and a second optical element for linearly imaging the light beam from the first optical element. An optical element, a rotary polygon mirror that deflects and scans the light beam from the second optical element, a driving unit that rotationally drives the rotary polygon mirror, and forms an image of the light beam from the rotary polygon mirror on a photosensitive member in a spot shape. A first optical box, and a synchronizing signal detecting means for obtaining a synchronizing signal of an image writing position on the photoreceptor, wherein the light beam from the third optical element is transmitted to the photoreceptor. A second optical box provided with a reflecting means for reflecting light to the first optical box, wherein the first optical box and the second optical box are integrally fixed. Light deflection scanning device. 2. The method according to claim 1, wherein the coupling unit includes a first optical box and a second optical box.
2. The optical deflection scanning device according to claim 1, wherein the optical box is fixed after adjusting the relative position of the optical box.