JPH09243902A - Optical device having adjusting mechanism for long-sized mirror and method for adjusting long-sized mirror for this device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to easily adjust the long-sized mirror of an optical device with good accuracy. SOLUTION: A first target block 80 is provided with a first gage line 81 extending in its longitudinal direction. When this first target block 80 is mounted at an optical base 1, the first reference line 81 parallels with a main scanning direction Y. The adjustment of the long-sized mirror 40 is then made possible in such a manner that the incident light on the first target block 80 is made incident along the first reference line 81. A second target block 90 is also provided with a second reference line 91 in the same manner as with the first target block 80. When the second target block 90 is mounted at side plates 2, 3, the second reference line 91 parallels with the main scanning direction Y. The adjustment of the long-sized mirror 40 is then made possible in such a manner that the incident light on the second target block 90 is made incident along the second reference line 91.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for adjusting a long mirror in an optical device for forming a linear image on the exposure surface by returning light to the exposure surface by a long mirror.

[0002]

2. Description of the Related Art FIG. 4 is a perspective view showing a background art of the present invention, and is a view showing a light beam scanning device which is an example of an optical device. This light beam scanning device (optical device) reflects and deflects the light beam from the optical unit 10 by the polygon mirror 20, and the scanning lens 30,
The exposure surface (scanned surface) S is configured to scan in the main scanning direction Y via the elongated mirror 40 and the cylindrical lens 50, and a linear image (line) in the main scanning direction Y is formed on the exposure surface S. Image).

By the way, when the light beam is folded back using the long mirror 40 as in the above-mentioned light beam scanning device, the long mirror 40 is adjusted so that the line image on the exposure surface S is parallel to the main scanning direction Y. Need to do. This is because if the long mirror 40 is not properly adjusted, the line image may be tilted,
This is because the image quality is deteriorated.

Therefore, conventionally, there has been proposed a technique for adjusting the elongated mirror 40 using the target block 60 shown in FIGS. 5 and 6, for example. The target block 60 shown in FIG. 5 is provided with a pinhole 61 as a target, and the target block 60 shown in FIG. 6 is provided with a marked line 62 as a target. The long mirror 40 is adjusted while observing how the light from the mirror 40 travels. Specifically, for example, they are arranged on the optical axis OA in the vicinity of the exposure surface side of the elongated mirror 40 and in the vicinity of the exposure surface S on the elongated mirror side. The long mirror 40 while observing how the light beam travels so that the worker passes through the line 62).
To adjust.

[0005]

However, according to the adjustment method as described above, the light beam folded by the elongated mirror 40 at the center of the angle of view (optical axis OA) is located at a desired position on the exposure surface S. Although guided, the angle of view is not adjusted, and the light beam folded by the elongated mirror 40 may be guided to a position on the exposure surface S that is deviated from the desired position. That is, according to the conventional adjustment method, although the linear optical path (center of view angle) connecting the targets of the two target blocks 60 can be adjusted, the entire view angle range (from one view angle end to the other view angle end). It is difficult to adjust the front range up to the corner edge).

Further, even if the long mirror 40 is adjusted over the entire angle of view by adjusting the angle of view ends, it is necessary to perform the adjustment of the other end every time the adjustment of one end of the image is performed. Therefore, it takes a long time to adjust the long mirror 40, and it is difficult to perform the adjustment accurately.

Incidentally, such a problem is not a problem peculiar to a light beam scanning device which scans a light beam to form a line image on the exposure surface S. For example, a slit-shaped light from an original such as an electrophotographic device is used. This is also a problem that occurs in an optical device that folds back light by a long mirror and guides it to a predetermined drum (exposure surface).

The present invention is intended to overcome the above-mentioned problems in the prior art, and an optical device provided with an adjusting mechanism for a long mirror capable of easily and accurately adjusting the long mirror in an optical device, It is a first object to provide a method for adjusting a long mirror in the device.

Further, the present invention provides an optical device having a long mirror adjusting mechanism capable of adjusting the long mirror more accurately and in a short time, and a long mirror adjusting method in the device. The second purpose is to provide.

[0010]

According to a first aspect of the present invention, a long mirror extending substantially parallel to a reference direction folds light from one side and guides it to an exposure surface, and on the exposure surface, the reference direction An optical device for forming parallel linear images,
In order to achieve the first object, a first target is provided in the longitudinal direction of the first target block, and the first target block is attachable to and detachable from the optical device in the vicinity of the exposure surface side of the elongated mirror, and in the longitudinal direction thereof. A second target is provided and is removable from the optical device in the vicinity of the exposure surface.
A target block, and further comprising an adjusting mechanism for the elongated mirror, wherein the first and second target blocks are attached to the optical device, and the first and second targets are parallel to the reference direction. There is.

According to a second aspect of the present invention, in order to achieve the second object, the first target block attached to the optical device directs at least a part of the light from the elongated mirror to the exposure surface side. It is configured to guide light.

According to a third aspect of the present invention, the first target block is partially provided with a hole along the first target for guiding the light from the elongated mirror to the exposure surface side. .

According to a fourth aspect of the present invention, the first target block is formed of a translucent member.

According to a fifth aspect of the present invention, a long mirror extending substantially parallel to the reference direction folds light from one side and guides it to the exposure surface, and a linear image parallel to the reference direction on the exposure surface. A method of adjusting a position of the long mirror, wherein the first target is provided with a first target in a longitudinal direction thereof in order to achieve the first object. Attaching the block to the optical device in the vicinity of the exposure surface side of the elongated mirror so that the first target is parallel to the reference direction; and a second target provided with a second target in the longitudinal direction thereof. A block is attached to the optical device in the vicinity of the exposure surface so that the second target is incident along the reference direction; and light incident on the first target block is Note: adjusting the elongated mirror so as to be incident along the first target, and adjusting the elongated mirror so that light incident on the second target block is incident along the second target. And a step of performing.

According to a sixth aspect of the invention, in order to achieve the second object, a target for guiding at least a part of incident light to the exposure surface side is used as the first target block, and the elongated mirror is used. The light from the first and second
The light is incident on the targets at the same time, the incident light on the first target is incident along the first target, and the incident light on the second target is incident along the second target. Adjusting the scale mirror.

According to the present invention, when the first target is provided in the first target block in the longitudinal direction and is attached to the optical device, the first target becomes parallel to the reference direction, and the light incident on the first target block is the above-mentioned. First
The elongated mirror can be adjusted so that it is incident along the target. Further, when the second target is provided in the second target block in the longitudinal direction and attached to the optical device, the second target becomes parallel to the reference direction, and the light incident on the second target block becomes parallel to the second target. So that the long mirror can be adjusted.

Further, since the first target block guides at least a part of the light from the long mirror to the exposure surface side, the light from the long mirror is incident on the first and second targets at the same time, and The incident light on the target is incident along the first target, and the incident light on the second target is incident along the second target,
The long mirror can be adjusted.

[0018]

1 is a view showing an embodiment of an optical device according to the present invention. In this optical device, an optical unit (not shown), a polygon mirror 20, and a scanning lens 30 are fixed on the optical base 1, and a light beam from the optical unit enters the polygon mirror 20 and is deflected and reflected. After that, the light is guided to the elongated mirror 40 extending in the main scanning direction (reference direction) Y through the scanning lens 30.

The elongated mirror 40 is arranged on the optical base 1 while being held by the mirror holder 70, and turns the incident light beam upward. Mirror holder 7
As shown in FIG. 2, 0 has a holder base 71 that extends substantially parallel to the main scanning direction Y and is movable on the optical base 1 in the front-back direction Z orthogonal to the main scanning direction Y. The holder base 71 is provided with elongated holes 72 at two positions, respectively, and after properly positioning the holder base 71 in the front-back direction Z, the holder base 71 can be fixed to the optical base 1 by the fixing screw 73. ing. In this way, the positioning adjustment of the elongated mirror 40 held by the mirror holder 70 in the front-rear direction Z can be performed.

Pressing springs 74 and 75 are attached to both ends of the holder base 71 so as to be rotatable about the axis AX, and hold the both ends of the elongated mirror 40, respectively. Then, from the holder base 71 to the long mirror 4
An angle adjusting push screw 76 is pressed against the back surface of 0, and the angle of the elongated mirror 40 can be adjusted by moving the push screw 76 forward and backward with respect to the holder base 71.

Returning to FIG. 1, the description of the structure of the optical device will be continued. When the long mirror 40 is adjusted, the first target block 80 is mounted on the optical base 1 at a predetermined position by the first target support member 84, as shown in FIG. The block 80 and the like are removed, and the light beam returned by the long mirror 40 is reflected by the cylindrical lens 50.
Is guided to the exposure surface (not shown) via. The cylindrical lens 50 is mounted in a state of being accurately positioned so as to be sandwiched between the first side plate 2 and the second side plate 3 which are connected and fixed to both side surfaces of the optical base 1.
When adjusting the elongated mirror 40, the cylindrical lens 50 is removed, and the second target block 90 is provided near the exposure surface with the second target support member 92.
It is attached at a predetermined position by a and 92b. Also,
For normal operation, the second target block 90 and the like are removed.

Thus, during normal operation, the first and second target blocks 80, 90 are removed, and FIG.
The device has the same configuration as that of the above-mentioned apparatus, and while the light beam is emitted from the optical unit (not shown in FIG. 1), the polygon mirror 20 is rotated to scan the light beam in the main scanning direction Y to the exposed surface. A line image parallel to the main scanning direction Y can be formed.

On the other hand, when the elongated mirror 40 is adjusted prior to the normal operation, the first and second target blocks 80 and 90 are attached to the optical base 1 and the side plates 2 and 3, respectively. Hereinafter, the first and second target blocks 8 functioning as an adjusting mechanism of the elongated mirror 40.
A detailed configuration of 0 and 90, an attachment state to the optical device, and a method of adjusting the elongated mirror 40 using the first and second target blocks 80 and 90 will be described.

FIG. 3 is an exploded perspective view showing the adjusting mechanism of the long mirror in the optical device of FIG. The long mirror 40 is arranged on the optical base 1 by the mirror holder 70 as described above. The long first mirror 40 is slightly longer than the long mirror 40 so as to cover the long mirror 40 from above. Target block 80 is arranged and long mirror 4
It is located near the exposure surface side of 0. on the other hand,
The long mirror 40 is provided near the exposed surface away from the long mirror 40.
An elongated second target block 90 having a slightly longer length is arranged.

The first target block 80 is formed of, for example, a diffusion plate such as frosted glass, and on the upper surface side thereof, two first marked lines 81 are provided in the longitudinal direction and along the marked lines 81. And a plurality of elongated holes 82 are provided. Further, mounting holes 83 are provided at both ends of the first target block 80.
The first target block 80 can be connected to the first target support member 84 by means of screws 85 via.
At both ends of the first target support member 84, target side reference holes 8 for positioning the optical base 1 are provided.
6a, 86b are provided, and these reference holes 86a,
The first target block 80 is connected to the first target support member 84 so that the virtual reference line 87L connecting 86b and the first marked line 81 are parallel to each other. The first target support member 84 is provided with a rectangular opening 87 for guiding the light beam from the elongated mirror 40 to the first target block 80, as shown in FIG.

Further, the optical base 1 is provided with base side reference holes 4a and 4b for accurately positioning the first target block 80, and the target side reference hole 86a of the first target support member 84 is arranged from above. , 86
By inserting the positioning pins 88a and 88b into the base-side reference holes 4a and 4b through b, the first target block 80, the first target support member 84, and the connected body can be positioned on the optical base 1. There is. Here, these base side reference holes 4a and 4b
Are provided so that the virtual reference line 5 connecting them is completely parallel to the main scanning direction Y, so that the virtual reference lines 5, 8
7L and the first marked line 81 are completely parallel to each other, and the first marked line 81 of the first target block 80 attached to the optical base 1 as described above is also completely parallel to the main scanning direction Y. By pulling out the positioning pins 88a and 88b, the first target block 80, the first target support member 84, and the connecting body can be easily removed from the optical base 1. As mentioned above,
The first target block 80 is the optical base 1 of the optical device.
When the first target block 80 is attached to the optical base 1, the first marked line 81 becomes completely parallel to the main scanning direction Y.

On the other hand, the second target block 90 is made of, for example, a diffuser such as frosted glass, has two second marked lines 91 on its upper surface, and has second target support members 92a, 92b at both ends. However, as in the case of the first target block 80, the virtual reference line connecting the target reference holes provided in each is connected to the second reference line 91 so as to be parallel. Target side reference hole 93a of one second target support member 92a
Is a side plate side reference hole 6 of the first side plate 2 from the side portion of the optical device.
The positioning pin 94a (FIG. 1) can be inserted through a. Although not clear in the drawing, a target side reference hole is similarly provided in the other second target support member 92b, and positioning is performed from the side portion of the optical device through the side plate side reference hole of the second side plate 3. The pin 94b (FIG. 1) can be inserted into the target side reference hole. In this way, the positioning pins 94a and 94b are moved to the second position.
When inserted into the reference holes of the target support members 92a and 92b, the second target block 90 is attached to the optical device. Moreover, the first and second side plates 2 and 3 are accurately attached to the optical base 1 in accordance with the predetermined design specifications, and the side plate side reference hole has the virtual reference line 7 connecting them in the main scanning direction Y. And the second target line 90 of the second target block 90.
Is completely parallel to the main scanning direction Y. By pulling out the positioning pins 94a and 94b, the second target block 90, the second target support members 92a and 94b, and the connecting body can be easily removed from the side plates 2 and 3. As described above, the second target block 90 is attachable to and detachable from the side plates 2 and 3 of the optical device, and when the second target block 90 is attached to the side plates 2 and 3, the second marked line 91 indicates the main scanning direction. It is completely parallel to Y.

Next, a method of adjusting the long mirror 40 will be described.

First, with the side plates 2 and 3 removed, the optical part, the polygon mirror 20 and the scanning lens 30 are arranged on the optical base 1, and these are adjusted and fixed by a conventionally known method. After that, after connecting the side plates 2 and 3 to the optical base 1, the mirror holder 70 is temporarily fixed on the optical base 1 while holding the elongated mirror 40. The cylindrical lens 50 is attached to the side plates 2 and 3 after the adjustment of the long mirror 40 is completed. The reason will be described later.

Next, the virtual reference line 8 connecting the reference holes 86a and 86b of the first target support member 84 as described above.
The first target block 80 is attached to the first target support member 84 so that 7L and the first marked line 81 are parallel to each other.
And the positioning pin 88 through the target side reference holes 86a and 86b of the first target support member 84.
a and 88b are inserted into the base-side reference holes 4a and 4b, respectively, and the connector is positioned on the optical base 1. As a result, the first target block 80 is located near the exposure surface side of the elongated mirror 40, and the first marked line 81 is also completely parallel to the main scanning direction Y.

Further, as described above, the second target block 90 is so arranged that the virtual reference lines connecting the reference holes provided in the second target support members 92a and 92b are parallel to the second reference line 91. After being connected to both ends of the connector, the positioning pins 94a and 94b are inserted into the reference holes of the second target support members 92a and 92b, and the connector is attached to the side plates 2 and 3. As a result, the second target block 90 is located in the vicinity of the exposure surface, and the second marked line 91 is also completely parallel to the main scanning direction Y.

When the mounting process of the first and second target blocks 80, 90 is completed as described above, a light beam is emitted from the optical section and the polygon mirror 2
Rotate 0 at low speed. Then, as shown in FIG. 1, the deflected light beam from the polygon mirror 20 is returned to the elongated mirror 40 while scanning in the main scanning direction Y and is incident on the first target block 80. For this reason, an operator visually observes that the light beam has a long mirror 40 in the entire angle range.
It is possible to recognize the route in which the light beam is traveling in the vicinity of, and it is possible to easily determine whether the scanning direction of the light beam coincides with the main scanning direction Y by comparing with the first marked line 81. You can Also, the first target block 8
Since 0 is formed of ground glass and a plurality of elongated holes 82 are provided, part of the light beam incident on the first target block 80 is incident on the second target block 90. Therefore, similarly to the first target block 80 side, the operator can recognize by visual observation what path the light beam travels on the exposure surface side in the entire angle range, and the second marked line. By comparing with 91, it is possible to easily determine whether the scanning direction of the light beam matches the main scanning direction Y.

When the scanning direction of the light beam does not coincide with the main scanning direction Y, the operator observes the scanning state of the light beam on the first and second target blocks 80 and 90 while By operating the front-back adjustment knob 89 and / or the angle adjustment push screw 76 attached to the 1 target support member 84, the light beam is parallel to the first and second marked lines 81 and 91, and The longitudinal direction and the angle of the elongated mirror 40 are adjusted so as to scan between the two marked lines in each of the second target blocks.

When the adjustment of the elongated mirror 40 is completed, the mirror holder 70 is fixed to the optical base 1, and then the connecting body of the first target block 80 and the first target support member 84 is connected from the optical base 1 to the second base. Target block 90 and second target support members 92a and 92b
Remove the connecting body of and from the side plates 2 and 3, respectively. Then, the cylindrical lens 50 is fixed to the side plates 2 and 3.

As described above, according to this embodiment,
It is possible to observe the scanning state of the light beam in the vicinity of the exposure surface of the elongated mirror 40 and in the vicinity of the exposed surface in the entire angle range of view, and the elongated mirror 40 can be adjusted while observing the situation. it can. Therefore, it is not necessary to move the target block to both ends of the angle of view when adjusting the long mirror 40 as in the conventional case, and the long mirror can be adjusted easily and accurately.

The reason why the cylindrical lens 50 is removed when adjusting the elongated mirror 40 as described above is as follows. That is, when the elongated mirror 40 is adjusted with the cylindrical lens 50 still attached to the side plates 2 and 3, the light beam reflected by the elongated mirror 40 is reflected by the cylindrical lens 50.
Even if the light beam is deviated from the optical axis of, the light beam is guided on the optical axis by the action of the cylindrical lens 50.
This is because if the spot size on the exposure surface becomes large or the side lobe becomes large, a problem occurs. In this regard, according to the above-described embodiment, the elongated mirror 40 is adjusted with the cylindrical lens 50 removed in advance. Therefore, such a problem does not occur, and by attaching the cylindrical lens 50 after the completion of the adjustment, a good spot size can be obtained over the entire range of the angle of view.

The procedure for attaching and detaching the first and second target blocks 80, 90 is not limited to the above-mentioned procedure. For example, one target block is attached to the optical device to adjust the elongated mirror 40. After that, the other target block may be attached to the optical device to adjust the elongated mirror 40. However, according to the above-described embodiment, a part of the incident light beam is exposed from the first target block 80. Since the light beam from the long mirror 40 is incident on the first and second target blocks 80 and 90 at the same time, the long mirror is exposed to the vicinity of the exposure surface side and the exposure. The scanning direction of the light beam can be adjusted to be parallel to the main scanning direction Y in both the vicinity of the surface, and the adjustment of the elongated mirror 40 can be performed in a shorter time and further. It can be carried out every time well.

Further, in the above embodiment, the marked lines 81 and 91 as the targets are provided on the upper surfaces of the first and second target blocks 80 and 90, but the kind of the target is not limited to the marked lines. Instead of providing a slit in the longitudinal direction of the target block instead of the marked line,
A plurality of pinholes may be arranged. Also,
A marked line may be formed on the lower surface side of the target blocks 80 and 90. In this case, it is possible to observe how the light beam is reflected by the target block to judge how the light beam is scanning. Become.

In the above embodiment, the first and second target blocks 80 and 90 are formed of a semitransparent diffusion plate. However, the target block is made of a transparent material such as glass or an opaque material such as metal. You may form. However, in order to adjust the scanning direction of the light beam to be parallel to the main scanning direction Y both in the vicinity of the exposure surface side of the elongated mirror and in the vicinity of the exposure surface at one time, the second target block 90 is sufficient. It is desirable that at least the first target block 80 is formed of a translucent material including a semitransparent material and a transparent material so that a light beam of a light amount is incident.

Furthermore, in the above-mentioned embodiment, the optical device for returning the light beam from the scanning lens 30 upward by the elongated mirror 40 has been described, but the application of the present invention is limited to this optical device. Needless to say, the present invention can also be applied to an optical device that is folded back downward. In addition to an optical device that scans a light beam (light beam scanning device), light that spreads in a reference direction (a direction corresponding to the main scanning direction in the above embodiment) like a reading optical system of an electronic copying apparatus. The present invention can be applied to all devices that fold back a long mirror.

[0041]

As described above, according to the present invention, the first
The first target block is attached to the optical device so that the target is parallel to the reference direction, and the elongated mirror can be adjusted so that the light incident on the first target block is incident along the first target. Attaching the second target block to the optical device so that the second target is parallel to the reference direction, and adjusting the elongated mirror so that the light incident on the second target block is incident along the second target. The long mirror in the optical device can be adjusted easily and accurately.

Further, since the first target block is configured to guide at least a part of the light from the elongated mirror to the exposure surface side, the light from the elongated mirror is directed to the first and second targets. At the same time, the incident light on the first target is incident along the first target,
The elongated mirror can be adjusted so that the incident light incident on the second target is incident along the second target, and the adjustment of the elongated mirror can be performed more accurately and in a short time.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of an optical device according to the present invention.

FIG. 2 is a perspective view of a long mirror when viewed from the back side.

FIG. 3 is an exploded perspective view showing an adjustment mechanism of a long mirror in the optical device of FIG.

FIG. 4 is a perspective view showing an example of an optical device which is a background art of the present invention.

FIG. 5 is a diagram showing a target block conventionally used for adjusting a mirror.

FIG. 6 is a diagram showing a target block conventionally used for adjusting a mirror.

[Explanation of symbols]

 40 Long Mirror 70 Mirror Holder 80, 90 Target Block 81, 91 Mark (Target) 82 Oblong Hole (Hole) S Exposure Surface Y Main Scanning Direction (Reference Direction)

Claims (6)

[Claims] 1. An optical device for folding back light from one side and guiding it to an exposure surface by a long mirror extending substantially parallel to the reference direction, and forming a linear image parallel to the reference direction on the exposure surface. In the above, a first target is provided in the longitudinal direction, a first target block that is detachable from the optical device in the vicinity of the exposure surface side of the elongated mirror, and a second target is provided in the longitudinal direction. A second target block that is attachable to and detachable from the optical device in the vicinity of the exposure surface, and when the first and second target blocks are attached to the optical device, the first and second targets move in the reference direction. An optical device having an adjusting mechanism for a long mirror, further comprising an adjusting mechanism for the long mirror that is parallel to the above. 2. The first device attached to the optical device.
The optical device having a long mirror adjusting mechanism according to claim 1, wherein the target block guides at least a part of the light from the long mirror to the exposure surface side. 3. The first target block is partially provided with holes along the first target for guiding light from the elongated mirror to the exposure surface side.
An optical device provided with the adjusting mechanism of the long mirror described in the above. 4. The optical device having a long mirror adjusting mechanism according to claim 2, wherein the first target block is formed of a translucent member. 5. An optical device that folds light from one side and guides it to an exposure surface by a long mirror extending substantially parallel to the reference direction, and forms a linear image parallel to the reference direction on the exposure surface. In the method of adjusting the position of the elongated mirror, the first target block in which a first target is provided in the longitudinal direction is arranged such that the first target is parallel to the reference direction. As described above, the step of attaching to the optical device in the vicinity of the exposure surface side of the elongated mirror, and the second target block in which the second target is provided in the longitudinal direction, the second target becomes parallel to the reference direction. Attaching to the optical device in the vicinity of the exposure surface, and the elongated length so that the light incident on the first target block is incident along the first target. An optical apparatus comprising: a step of adjusting a mirror; and a step of adjusting the elongated mirror so that light incident on the second target block is incident along the second target. How to adjust the long mirror. 6. A target for guiding at least a part of incident light to the exposure surface side is used as the first target block, and light from the elongated mirror is made incident on the first and second targets at the same time. Adjusting the elongated mirror so that incident light on the first target enters along the first target and incident light on the second target enters along the second target. The method for adjusting a long mirror in an optical device according to claim 5, wherein.