JPH09184951A - Slit exposure device, method for adjusting slit exposure optical system and image recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To satisfy the original image forming performance of a lens, to enhance the photographing resolution and the prevent the photographing resolution from being deteriorated even in the case of the decentered lens by arranging the lens so that it can be rotated with an optical axis as the center and the position thereof can be moved in an axial direction without rotating around it. SOLUTION: After a coil spring 14 and the lens 3 are inserted in a lens guide ring 11, an adjustment ring 13 for adjusting the focusing position of the lens is screwed in the front-end aperture part of the ring 11 and the male screw part 13a of the outside circumferential surface of the ring 13 is screwed to the female screw part 11a of the inside circumference of the front-end aperture part of the ring 11. By pressing and moving the lens 3 to the inside of the ring 11 at the inside end of the ring 13, the spring 14 is screwed while being screwed between the lens 3 and a ring-like flange seat 11c. Then, a pin 31 is inserted in the long hole 12 of the ring 11 and fixed to the lens 3. In such a way, the set lens 3 can be linealy moved in the front-and-back direction without being rotated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slit exposure apparatus, a slit exposure optical system adjusting method and an image recording apparatus for forming a subject image on a projection member surface by an optical system including a slit member and a lens.

[0002]

2. Description of the Related Art A slit exposure type image recording apparatus is a rotary camera (micro film photographing apparatus) for reducing and photographing a document image on a film, and a document image is imagewise exposed on a image carrier at a desired magnification. A copy machine to obtain a copy
2. Description of the Related Art There is an image reading device for photoelectrically reading and recording an image of a document on a one-dimensional solid-state image pickup device such as a CCD array.

In both cases, a subject image such as an original image is slit-formed by an optical system including a slit member and a lens on a projection member surface (recording medium surface) of a film, an image carrier, a solid-state image pickup device, or the like for recording. It is a thing.

As a specific example, FIG. 4 shows a perspective view of a schematic configuration of a slit optical system portion of a rotary camera. Reference numeral S denotes a sheet-shaped document as an object, which is fed from a feeding unit (not shown) and is conveyed by an unillustrated transporting means at a predetermined constant speed with an arrow P.
In the direction through the document illuminating section E to reach a sheet discharging section (not shown).
The transported document S is illuminated by the illumination lamp 1 in the process of passing through the document illumination section E, and the reflected light of the document surface of the illumination light passes through the slit 2a of the slit plate 2 and the lens 3 (lens barrel) to the capstan roller 4. A reduced projection image is formed by the slit exposure method on the surface of the film F that has been spun around.

The film F is a roll film in which the guide roller 6a, the capstan roller 4, and the guide roller 6b are sequentially wound around the supply reel 5 and locked to the take-up reel 7. The capstan roller 4 conveys the tape from the supply reel 5 side to the take-up reel 7 side in the direction of arrow R at a constant speed in synchronization with the reduction ratio of 3, and then winds the take-up reel 7.

Each time the document passes through the document illumination section E,
The film F is successively conveyed and driven, and the image information of the fed document is sequentially photographed and recorded on the film F, and the film portion having been photographed is wound on the take-up reel 7 side. When the filming for one roll of film is completed, it is sent to the developing process.

FIG. 5 shows the structure of the lens mount portion. Reference numeral 8 is a common mount member for the capstan roller 4 and the lens 3. The capstan roller 4 has its axis 4
a is supported by the bearing portion 8a of the mount member 8 via the one-way clutch bearing 9, and is rotatable only in the film advancing direction R, and the backward movement of the film F is prevented. The capstan roller 4 is rotated by transmitting a driving force to the shaft 4a by a driving unit (not shown).

The lens 3 is inserted into a lens insertion tube portion 8b formed integrally with the lens mount portion 8 and the lens insertion tube portion 8b is inserted.
A male screw portion 3a provided on the outer circumference of the lens 3 is screwed into a female screw hole portion 8c provided on the lens insertion cylindrical portion 8b so as to be rotatably fitted and supported on the lens insertion cylindrical portion 8b.

When the lens 3 is rotated in the forward or reverse direction, the lens 3 is moved to the optical axis OO with respect to the lens insertion tube portion 8b.
Since the position of the lens 3 is changed between the optical path lengths of the document S surface and the film F surface in the document illumination unit E by moving in the anteroposterior direction a and b, it is possible to perform focus (focus) adjustment. . Reference numeral 10 denotes a lens rotation stopping screw for fixing the position of the lens 3 with respect to the lens insertion tube portion 8b after focus adjustment.

[0010]

In the above-mentioned conventional example, the focus adjustment of the lens 3 is performed by rotating the lens 3 and moving the lens 3 through the male screw portion 3a and the female screw hole portion 8 so that the lens 3 is moved in the front-rear direction a.b. Since the lens 3 is rotated when the lens 3 is moved, the focus adjustment of the lens 3 involves the following problems.

That is, the optical use range of the lens 3 used in the slit exposure type apparatus such as the rotary type camera of the above-mentioned example is as follows:
Since it is regulated by the slit width of the slit 2a, the range is extremely limited. FIG. 6 shows the optical range of the lens 3 which is regulated by the slit 2a. With respect to the effective effective angle range ω of the lens 3 of the lens 3, with respect to the scanning direction P of the subject S, it depends on the slit width c of the slit 2a. Regulated within the range of θ.

On the other hand, in general, due to manufacturing errors in the lens 3, the centers of curvature of the individual surfaces forming the optical system deviate from the reference axis (optical axis) in various directions. For this reason, the actual lens has the eccentricity due to the above-mentioned deviation, though there is a difference in the degree.

As a result, although the image forming performance such as the resolving power of the lens originally has the characteristic of being rotationally symmetric about the optical axis, it becomes directional due to the influence of the eccentricity. In addition, aberrations and distortions that are usually called "one-sided blur" occur. FIG. 7 shows the direction of eccentricity (direction of arrow ε in the figure) and the distortion of the image (graphic) in an exaggerated manner.

Therefore, in the lens of the rotary type camera as in the above-described example, the lens 3 is rotated during focus adjustment, so that the lens use range (slit direction) regulated by the slit 2a coincides with the eccentric direction of the lens. The original imaging performance may be deteriorated, and the photographing resolution may be significantly decreased. Further, even when the eccentric direction of the lens does not coincide with the slit direction at the time of focus adjustment, it is necessary to change the focus position of the lens according to the thickness of the film F to be used. There was a problem that there was a difference in shooting resolution.

The present invention has been made in order to solve the above-mentioned problems of the prior art, and the purpose thereof is to satisfy the original image forming performance of the lens, improve the photographing resolution, and make the lens decentered. However, it is to utilize effectively without lowering the shooting resolution.

[0016]

The present invention is a slit exposure apparatus, a slit exposure optical system adjusting method, and an image recording apparatus characterized by the following configurations.

(1) In a slit exposure apparatus for forming a subject image on a projection member surface by an optical system including a slit member and a lens, the lens is rotatable about the optical axis and is rotatable in the optical axis direction. A slit exposure apparatus, wherein the slit exposure apparatus is arranged so as to be capable of position movement operation without being accompanied.

(2) The lens is housed in a lens guide ring covering the outer peripheral portion of the lens, and the pin provided relatively to the lens side and the lens guide ring side and the optical axis direction in which the pin is engaged are set. The slit exposure apparatus according to (1), wherein the slit exposure apparatus can be operated to move the position in the lens guide ring in the optical axis direction without being rotated by a guide means having a guide hole that is long.

(3) An urging member for urging the lens housed in the lens guide ring in one direction of the optical axis and a position movement operation in the optical axis direction for opposing the lens against the urging member. The slit exposure according to (2), further comprising an adjusting ring that receives the lens, and the lens moves in position in the lens guide ring in the optical axis direction without rotation in association with a position movement operation of the adjusting ring. apparatus.

(4) The lens guide ring is fitted to and supported by the mount member so as to be rotatable about the optical axis, and has means for stopping rotation of the lens guide ring on the mount member (2) or (3). ) Slit exposure apparatus described in.

(5) The rotation angle of the lens is such that the direction in which the resolving power of the directional characteristic of the image forming performance is good or the direction in which the resolving power does not decrease remarkably coincides with the slit direction of the slit member by the rotation operation about the optical axis. The slit exposure apparatus according to any one of (1) to (4), characterized in that the slit exposure apparatus is held at a position and at a position where focus adjustment is performed by a position movement operation in the optical axis direction.

(6) In a slit exposure apparatus for forming a subject image on the surface of a projection member by an optical system including a slit member and a lens, a lens whose directional characteristic of image forming performance is previously examined has a good resolving power of the directional characteristic. Direction or the direction where there is no significant reduction in resolving power is adjusted so that the rotation angle position matches the slit direction of the slit member, and the lens whose rotation angle position has been adjusted is moved in the optical axis direction without rotating to adjust the focus. The slit exposure optical system adjusting method is characterized in that the above-mentioned adjusted rotational angle position and optical axis direction position of the lens are held.

(7) An image recording apparatus for forming an image of a subject on a recording medium by slit exposure means and recording the image.
An image recording device, wherein the slit exposure means is the slit exposure device according to any one of (1) to (5).

<Operation> That is, in the present invention, the directional characteristic of the image forming performance (resolution) of the lens due to the influence of decentration is checked based on the projection resolving power measurement data obtained by backprojecting at the time of inspection with the lens alone. , The direction in which the resolving power is good or the direction in which the resolving power does not significantly decrease is aligned with the slit direction (longitudinal direction) of the apparatus main body and set in the lens mount portion. Further, focus adjustment is performed by linearly moving the set lens in the front-rear direction without rotating it.

The direction of the lens resolving power in the state of a single lens is taken into consideration in advance, and the lens direction is determined and incorporated in the apparatus, whereby the performance of the lens in slit exposure is fully brought out and the photographing resolving power is improved. It is possible.

Further, at the time of focus adjustment, by moving the lens back and forth while maintaining the direction in which the lens itself is set without being rotated, the lens performance is not deteriorated and films having different thicknesses are used. Even when the focus of the lens is adjusted when it is used, it is possible to obtain stable photographing resolution without variation.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION

<Embodiment 1> (FIGS. 1 and 2) FIG. 1 shows a configuration of a lens mount portion of an image recording apparatus according to the present invention. The image recording apparatus of this example is shown in FIG.
It is a rotary camera similar to ~ 7 and has common components
The same reference numerals are given to the parts, and the repeated description will be omitted.

In FIG. 1, reference numeral 11 is a lens guide ring. The lens guide ring 11 has a female screw portion 11a on the inner peripheral surface on the front end opening side and a male screw portion 1 on the outer peripheral surface on the rear end opening side.
1b, an annular collar seat 11c is formed inward at the rear end opening, and a guide slot 12 having a longitudinal direction in the optical axis direction OO is formed on the outer surface.

A coil spring 14 and a lens (lens barrel) 3 are inserted and housed in the lens guide ring 11 from the front end opening side. Coil spring 1
4 is received by the annular collar seat 11c of the lens guide ring 11 and is prevented from coming off.

Reference numeral 13 is an adjusting ring for adjusting the focus position of the lens. After the coil spring 14 and the lens 3 are inserted into the lens guide ring 11, the adjusting ring 13 is inserted into the front end opening of the lens guide ring 11. The outer peripheral surface male thread portion 13a of the adjusting ring is screwed into the inner peripheral female thread portion 11a of the front end opening of the lens guide ring 11, and the lens 3 is pushed inward by the inner end of the adjusting ring 13. The coil spring 14 is screwed while being contracted between the lens 3 and the annular collar seat 11c. Then, a pin 31 is inserted into the elongated guide hole 12 of the lens guide ring 11 and fixed to the lens 3.

Therefore, the lens 3 can be slidably moved in the optical axis direction OO without rotation in the lens guide ring 11 by the guide means of the pin 31 and the elongated guide hole 12 without any rotation. In addition, the compression reaction force of the coil spring 14 causes the inside of the lens guide ring 11 to move forward in the optical axis direction OO.
The lens front end is received by the inner end of the adjusting ring 13, and the lens 3 is rotated by the lens guide ring 11 by rotating the adjusting ring 13.
It is possible to move the position (focus position adjustment) in the front-rear direction a and b in the optical axis direction OO without rattling without rotation.

That is, when the adjusting ring 13 is rotationally operated in the direction in which it is extended from the lens guide ring 11, the lens 3 is moved by the coil spring 14 by the movement biasing force of the coil spring 14 following the extension movement of the adjustment ring 13. The sliding position is moved in 11 in the front direction a of the optical axis direction OO without rotation. On the contrary, when the adjusting ring 13 is rotated in the direction to be screwed into the lens guide ring 11, the lens 3 is pushed against the coil spring 14 by the amount of the screwing movement, and the coil spring 14 is compressed while the lens guide ring 11 is illuminated. The sliding position moves in the rearward direction b of the axial direction OO without rotation.

The lens guide ring 11 assembled with the lens 3, the coil spring 14, the pin 31, the adjusting ring 13 and the like as described above is provided at the rear end opening of the lens guide ring insertion cylindrical portion 8b integrally formed with the lens mount portion 8. Side is inserted first, and the male threaded portion 3a provided on the outer periphery of the rear end opening of the lens guide ring 11 is screwed into the female threaded hole portion 8c provided in the insertion tubular portion 8b to insert the tubular portion 8b. It is rotatably supported. Reference numeral 10 is a rotation stop screw for fixing the position of the lens guide ring 11 with respect to the insertion tube portion 8b.

FIG. 2 shows the measuring direction of the resolving power in order to check the directional characteristic of the lens 3. The aerial resolving power (M and S directions) is measured in the directions A to D based on the optical axis O. At this time, it is desirable to take as many measurement directions as possible.

In this way, based on the data of the measured resolving power, a direction in which the resolving power is good or a direction in which the resolving power does not significantly decrease is selected, and this direction is set with reference to the pin 31 fixed to the lens 3. Data is made in correspondence with the angle α. In the example of FIG. 2B, the direction of BB 'is shown.

Then, in FIG. 1, the lens guide ring 11 accommodating the lens 3 is rotationally operated with respect to the insertion tube portion 8b, and the direction of the angle α is set to the slit plate 2 of the apparatus main body.
Direction of the slit 2a in (Fig. 4) (longitudinal direction of the slit)
Adjust the rotation angle to match. That is, the rotational angle position of the lens whose directional characteristic of the imaging performance is previously checked is adjusted so that the direction in which the directional characteristic is good in the resolving power or the direction in which the resolving power does not significantly decrease coincides with the slit direction of the slit member 2. After adjusting the rotational angle position, the lens guide ring 11 is prevented from rotating with respect to the insertion tube portion 8b by the fixing screw 10. Since the direction of the slit 2a is generally perpendicular to the direction of travel of the film F, it is the same as the axial direction of the capstan roller 4.

Next, the lens guide ring 1 which has been prevented from rotating as described above.
The focus position of the lens 3 is adjusted by rotating the adjusting ring 13 with respect to 1. The position of the lens 3 whose focus position has been adjusted is held unless the adjusting ring 13 is rotated.

As described above, when the focus position of the lens 3 is adjusted, the lens 3 is not rotated, and the lens 3 has a preliminarily adjusted optimum rotation angle position with respect to the slit member 2, that is, a good resolving power of the directional characteristic of the image forming performance. Since the rotation angle position in which the direction of the lens or the direction in which the resolving power does not significantly decrease coincides with the slit direction of the slit member is maintained, the original image forming performance of the lens is satisfied, the photographing resolving power is improved, and a lens with decentering exists. However, it is possible to effectively utilize the image without reducing the resolution. Further, even when the focus of the lens is adjusted when films having different thicknesses are used, it is possible to obtain stable photographing resolution without variation.

As a method for confirming whether or not the surface of the film F is in focus, (a) an object for image checking called "chart" is moved back and forth by a predetermined amount while moving the position of the lens 3 forward and backward, respectively. An image having the best focus is selected from the images actually recorded on the film after development and recorded on the film, and the position of the lens 3 with respect to the image is set as the in-focus position. (B) An image sensor such as a CCD is placed at a position corresponding to the F surface of the film instead of the film, and similarly, the image of the "chart" is read by the CCD while moving the position of the lens 3 by a predetermined amount, and the output is obtained. While checking on the monitor, find the in-focus position of the lens 3.

In any of the above cases, the predetermined amount of movement of the lens 3 each time is preferably less than or equal to the depth of focus of the lens 3, and the amount of movement of the lens 3 before and after is the amount of rotation of the adjusting ring 13. It corresponds to.

Therefore, a mark such as a projection is provided on a part of the outer circumference of the adjusting ring 13, and graduations (indexes) at equal intervals are attached to the outer peripheral part of the non-rotating lens guide ring 11 so that the adjusting ring 13 can be adjusted. The front and rear position of the lens 3 can be recognized from the rotational position.

There are usually three types of film thickness (5 m
1 mil is 1 mil, 4 mil, 2.5 mil
Since it is / 1000 inch (inch), one kind of film (for example, 5 mi
When a film having a thickness different from that of marking is provided by adjusting in accordance with 1), focusing is performed so that the lens 3 can be moved back and forth by the difference in film thickness. Therefore, as shown in FIG. 8, a seal indicating the difference in film thickness from the reference film is attached to the marking portion and attached to the lens guide ring 11.

Therefore, the focus can be easily adjusted / confirmed by rotating the adjusting ring 13 according to the film used by the user or the service person and aligning the protrusion with the display of the sticker.

<Embodiment 2> (FIG. 3) In Embodiment 1 described above, the lens guide ring 11 accommodating the lens 3 is screwed into the insertion cylinder portion 8b of the mount portion 8 with the screw portions 11b and 8c. Although it is provided rotatably with respect to the insertion tube portion 8b, in this example, as shown in FIG. 3, the screw portion is abolished and the lens guide ring 11 is incorporated in the insertion tube portion 8b.

That is, an annular collar seat 8d is formed inward at the rear end opening of the insertion tube portion 8b, and the lens guide ring 11 is provided in the insertion tube portion 8b at the front end opening side of the insertion tube portion 8b. Has a straight outer peripheral surface shape that is inserted from the inside of the insertion tube until the end surface of the rear end opening of the lens guide ring 11 is received by the inward annular collar seat 8d of the rear end opening of the insertion tube portion 8b. Fully insert into part 8b. The other configurations are similar to those of the first embodiment, and thus the repetitive description will be omitted.

In this example, if the fixing screw 10 is loosened, the lens guide ring 11 can be freely rotated with respect to the insertion tube portion 8b, and the lens guide ring 11 can be rotated.
The focus position of the lens 3 does not change by maintaining the state of abutting against the inward annular collar seat 8d on the insertion tube portion 8b side.

Therefore, in this example, the lens guide ring 11 is rotated with the focus position of the lens 3 maintained after the lens 3 is sufficiently inserted into the insertion tube portion 8b until it is received by the annular collar seat 8d. This has the effect that the directional characteristics (imaging resolution) of the lens can be checked with the lens set in the apparatus. After the check, the fixing screw 10 is tightened to fix the lens 3 by preventing the lens 3 from rotating with respect to the insertion tube portion 8b.

As a method for checking the directional characteristic of the lens, the lens is set in the apparatus (the focus position of the lens is fixed), the lens is divided into several rotations within a half rotation range, and the lens is rotated every time. Take the chart. After the development, an image having a good resolution or an image without significant deterioration is selected from the images recorded on the film, and the lens guide ring 11 is fixed according to the rotational position of the lens 3 (lens guide ring 11) at that time.

Further, as in the case of adjusting the focus, a CCD may be used instead of the film, and confirmation may be performed on a monitor.

Although the first and second embodiments are about the rotary type camera, the present invention is not limited to this, and is widely applied to a slit exposure type apparatus such as a copying machine and an image reading apparatus, and a slit exposure optical system adjusting method. Of course, the same effect can be obtained. The means mechanism for arranging the lens so that it can be rotated about the optical axis and can be moved in position without rotation in the optical axis direction is not limited to the specific examples of Embodiments 1 and 2. Of course not.

[0051]

As described above, according to the present invention,
Based on the measured data of the projected resolving power of the lens measured in advance, the directional characteristics of the lens performance are checked, and the direction in which the resolving power is good or the direction in which the resolving power does not significantly decrease is matched with the slit direction of the device body, and is mounted on the mount part. By setting and moving the set lens linearly in the front-rear direction without rotating and adjusting the focus, it is possible to effectively utilize the lens performance and improve the photographing resolution.

Further, even a lens having a significant decentering such as "one-sided blur", which has conventionally been dropped due to a manufacturing error, can be effectively utilized.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a lens mount unit in an apparatus according to a first embodiment.

FIG. 2 is an explanatory diagram of the directionality of lens performance.

FIG. 3 is a configuration diagram of a lens mount unit in the device according to the second embodiment.

FIG. 4 is a perspective view of a schematic configuration of a slit exposure optical system portion of a rotary camera.

FIG. 5 is a configuration diagram of a lens mount section.

FIG. 6 is a diagram showing an optical range of a lens regulated by a slit.

FIG. 7 is a diagram showing a lens decentering direction and image distortion.

FIG. 8 is an explanatory diagram of focus adjustment.

[Explanation of symbols]

S .. Document (subject), E .. Document illumination unit, 1 ... Document illumination lamp, 2 ... Slit plate, 2a ..., Slit, 3
..Lens (lens barrel), F ... Film, 4 ... Capstan roller, 5 ... Supply reel, 6a, 6b ...
Guide roller, 8 ... Mounting part, 8b ...
7 ... Winding reel, 10 ... Stop screw, 11 ... Lens guide ring, 12 ... Long guide hole, 13 ... Adjustment ring, 14
··coil spring

Claims (7)

[Claims] 1. A slit exposure apparatus for forming a subject image on a projection member surface by an optical system including a slit member and a lens, wherein the lens is rotatable about an optical axis and rotatable in the optical axis direction. A slit exposure apparatus, wherein the slit exposure apparatus is arranged so that the position can be moved without being accompanied by it. 2. A lens is housed in a lens guide ring covering an outer peripheral portion of the lens, and a pin provided relatively to the lens side and the lens guide ring side and an optical axis direction in which the pin is engaged are elongated. 2. The slit exposure apparatus according to claim 1, wherein the slit exposure apparatus can be operated to move the position in the lens guide ring in the optical axis direction without being rotated by the guide means with the guide hole. 3. A biasing member for biasing the lens housed in the lens guide ring to move in one direction of the optical axis, and a position movable in the optical axis direction for receiving the lens against the biasing member. 3. The slit exposure apparatus according to claim 2, further comprising an adjusting ring, wherein the lens moves in position in the lens guide ring in the optical axis direction without rotation in association with a position moving operation of the adjusting ring. . 4. The lens guide ring is fitted to and supported by a mount member so as to be rotatable about an optical axis, and the lens guide ring has means for stopping rotation of the lens guide ring on the mount member. Slit exposure device. 5. The lens has a rotation angle position in which the direction in which the resolution of the directional characteristic of the image forming performance is good or the direction in which the resolution does not significantly decrease is made coincident with the slit direction of the slit member by the rotation operation about the optical axis. 5. The slit exposure apparatus according to claim 1, wherein the slit exposure apparatus is held at a position where focus adjustment is performed by a position movement operation in the optical axis direction. 6. In a slit exposure apparatus for forming a subject image on a projection member surface by an optical system including a slit member and a lens, a lens whose directional characteristic of image forming performance is previously examined is used in a direction in which the directional characteristic has a good resolving power. Alternatively, adjust the rotation angle position so that the direction in which the resolving power does not significantly decrease matches the slit direction of the slit member, and move the lens position adjusted in that rotation angle position in the optical axis direction without rotating to adjust the focus. And a slit exposure optical system adjusting method for holding the adjusted rotational angle position and optical axis direction position of the lens. 7. An image recording device for forming an image of a subject image on a recording medium by a slit exposing means and recording the image, wherein the slit exposing means is the slit exposing device according to any one of claims 1 to 5. An image recording device characterized by the above.