JPH02123343A - Process camera - Google Patents

Abstract

PURPOSE:To horizontally arrange a platen and to make a camera compact by forming the picture of an original on an original platen arranged horizontally on a photosensitive material placed on the platen via two mirrors. CONSTITUTION:The title camera is provided with a mirror 14 which is arranged on the upper side of the original platen 11 and laterally reflects light from the original platen 11, an image forming lens 16 which is arranged on a light- reflecting optical path formed by the mirror 14 and a movable mirror 18 which is provided on the upper side of the platen 20 so as to advance to and retreat from the optical axis of the image forming lens and bends its optical axis in the direction of the platen 20 while it advances to the optical axis of the lens. The movable mirror 18 is equipped with an index plate 24 which is arranged so as to retreat from the optical axis of the lens and arranged in the conjugate position with the platen 20. Because the optical path which comes from the original platen 11 and reaches the platen 20 is bent by the two mirrors 14 and 18, the original platen 11 and the platen 20 can be closely arranged. Thereby, the original platen 11 and a platen 14 can be arranged horizontally and this horizontal arrangement makes the camera compact.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a fully bright room type prepress camera that is easy to handle, compact, and occupies less space. The present invention relates to a camera suitable for plate making while imposing a manuscript with a large number of pages onto a large photosensitive material.

(Prior Art) Regarding prepress cameras that impose manuscripts with many pages, for example, U.S. Pat.
Various types are known, as described in the specifications of No. 7°742 and No. 3,920,333. However, in the devices described in each of the above specifications, the document table for setting the H document and the platen for setting the photosensitive material are both vertically installed and face each other, so when setting the document and the photosensitive material, it is difficult to The original and the photosensitive material must be set on a vertical document table and platen, making handling of the original and the photosensitive material cumbersome. In addition, in order to ensure a predetermined optical path length from the document table to the platen, it is necessary to make the distance between the document table and the platen a certain length, which causes the problem that the entire camera becomes longer and occupies a larger area. Ta.

In addition, the specification and drawings of Utility Model Application No. 1983-93665, filed by the present applicant, disclose that by bending the optical path using a mirror, the image of the original on the horizontally arranged original platen can be changed vertically. A plate-making camera is described that can make an image on a photosensitive material placed on a platen. According to this plate-making camera, since the document table is installed horizontally, it is easy to handle the document. Furthermore, since the optical path is bent by the mirror, there is an advantage that the overall length of the camera can be shortened.

(Problems to be Solved by the Invention) In the plate-making cameras described in the above-mentioned US patent specification and the specification and drawings previously filed by the present applicant, at least the platen is installed vertically.

In order to prevent the photosensitive material from falling off the platen surface, it is necessary to handle the photosensitive material while making full use of a highly reliable suction device, and handling the photosensitive material is often troublesome and inconvenient. Also, the overall length of the camera is quite long, and there is room for improvement to make it more compact. Further, according to the plate-making camera filed by the present applicant, since a lens and one mirror are used, a normal image can be obtained, and the camera is suitable for producing direct printing plates. but.

If the photosensitive material is a negative version, a reversal image is required, so in that case, as described in the above-mentioned U.S. patent, the original and the photosensitive material are placed facing each other in a vertical plane, and an imaging lens is placed between them. A camera is used. However, according to the camera described in the above-mentioned US patent specification, there is no means for confirming the position of the original, and it is difficult to align the original. In other words, since there is no means for confirming the position of the original, the original and the photosensitive material are arranged vertically facing each other to facilitate alignment of the original.

The present invention has been made in order to solve the problems of the prior art, and makes it possible to install both the document table and the platen horizontally, thereby facilitating the handling of documents and photosensitive materials. The purpose of the present invention is to provide a prepress camera that can be made compact by allowing the platen to be installed in close proximity to the platen.

Another object of the present invention is to provide a plate-making camera that allows the size of the mirror to be used to be as small as possible, allowing the use of a mirror that is highly accurate and easy to manufacture.

(Means for Solving the Problem) The present invention includes a mirror that is placed above the document table and reflects the light from the document table to the side, and an imaging lens that is placed on the optical path reflected by this mirror. , a movable mirror that is provided above the platen so as to be movable forward and backward on the optical axis of the imaging lens, and that bends the optical axis of the lens toward the platen in a state where it extends onto the optical axis of the lens; When the mirror is retracted from the optical axis of the lens, it is characterized by having an index plate disposed on the optical axis of the lens and at a position conjugate with the platen.

The optical path from the mirror above the document table to the movable mirror through the imaging lens and further to the index plate may be inclined in the vertical direction so that the mirror side above the document table is in the upper position.

(Function) By retracting the movable mirror from the optical axis of the imaging lens, the image of the index plate is projected onto the document table, and by aligning the document with the image of this index, the document is correctly positioned on a slightly larger piece of film. It can be carried out. By advancing the movable mirror onto the optical axis of the lens, the image of the original on the document table is formed onto the photosensitive material on the platen through the mirror above the document table, the imaging lens, and the movable mirror. The image of the original can be imprinted onto the material. Since the optical path from the document table to the platen is bent by two mirrors, the document table and platen can be placed close to each other.

If the optical path is tilted vertically so that the mirror side above the document table is higher than the movable mirror, it is possible to shorten the horizontal distance between the two mirrors and secure a predetermined optical path length. Therefore, the document table and the platen can be arranged closer to each other. This helps reduce the mirror size and makes it easier to create mirrors with good smoothness and high resolution.

(Example) Hereinafter, an example of the prepress camera according to the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 11 indicates a document table.

The document table 11 is arranged horizontally on the outer surface of the camera housing 52, so that a document can be placed on the horizontal surface. Further, in order to prevent the original from moving unnecessarily, the original may be suctioned by an air-based original suction device. An illumination light source for illuminating the document on the document table 11 is arranged diagonally above the document table 11, but is not shown.

Above the document table 11, a mirror 14 is arranged at an angle of 45 degrees for horizontally bending light reflected from the document on the document table 11. The mirror 14 is held by a holder 34, which is screwed into a horizontal feed screw 36. The holder 34 is horizontally movable by suitable guide means, but is guided non-rotatably around the feed screw 36.

The rotation of the feed screw 36 is controlled by a stepping motor or the like.

An imaging lens 16, a movable mirror I8, and an index plate 24 are arranged in this order on an optical path where light from the document table 11 is reflected by the mirror 14. The imaging lens 16 is held by a holder 38. The holder 38 is screwed onto a horizontal feed screw 40. It is assumed that a shutter is attached to the holder 38 to open and close the optical path. Holder 38
is movable in the horizontal direction by appropriate guides 1 to 40, but is guided around the feed screw 40 in a non-rotatable manner. The rotation of the feed screw 40 is controlled by a stepping motor or the like.

A platen 20 is provided horizontally within the camera housing 52, and a relatively large piece of film as a photosensitive material can be positioned at a predetermined position in a horizontal plane by an air suction device (not shown). Platen 20 is X
, Y moving device 46 in one horizontal plane.
can move in the direction. Such movement in the X and Y directions is performed by rotationally driving a feed screw (not shown) by a stepping motor or the like. A mask plate 48 is arranged immediately in front of the film holding surface of the platen 20. The mask plate 48 consists of left and right mask plates and front and rear mask plates, and by moving these mask plates independently, the opening width in the X and Y directions can be arbitrarily set.

A device for conveying film pieces onto the platen and a device for feeding photographed film pieces into a developing machine are arranged near the platen 20, but these devices are not shown because they are not directly related to the present invention. Not yet.

The movable mirror 18 is rotatably supported around a shaft 44, and stands up at an angle of 45 degrees with respect to the optical axis of the imaging lens 16, as shown by the solid line in FIG.
It can take a position in which the optical axis of the lens is bent downward, or a position in which it rotates downward and retreats from the optical path of the imaging lens 16, as shown by a chain line 18A in FIG. When the movable mirror 18 extends onto the optical axis of the imaging lens 16, this lens 16
bend the optical axis toward the platen 20 at a right angle. An index plate 24 is disposed vertically on the optical axis of the lens 16 in a state where the movable mirror 18 is retracted from the optical axis of the lens 16. The index plate 24 is arranged at a position conjugate with the surface of the platen 20 with respect to the movable mirror 18 . Center lines are marked on the index plate 24 that are perpendicular to each other along the X and Y directions.

The indicator plate 24 can be covered with a lighting box body 30. By rotating the illumination box 30 about an appropriate axis, the indicator plate 24 can be opened and closed. An illumination light source for illuminating the index plate 24 is provided inside the illumination box 30.

When the movable mirror 18 extends onto the optical path of the imaging lens 16, an optical system for imaging the document on the document table 11 relative to the platen 20 is formed. On the other hand, in a state in which the movable mirror 18 is retracted from the optical path of the imaging lens 16, the illumination light source on the document side is turned on and the illumination light source on the index plate 24 side is turned off. Furthermore, by turning off the illumination light source on the document side and turning on the illumination light source on the index plate 24 side, an optical system for projecting the index plate 24 onto the document table 11 can be formed.

Next, the operation of the above embodiment will be explained.

First, a sheet of original is placed on the original platen 11 with the movable mirror 18 retracted from the optical axis of the lens 16 as shown by the chain line 18A. In this state, when the illumination light source on the document side is turned on, the image of the document is displayed on the mirror 14. An image is formed on the index plate 24 through the imaging lens 16, and the state of this image formation can be observed from the outside by opening the illumination box 30. Since a center line in the orthogonal direction is marked on the index plate 24, align the document while moving it on the document table 11 so that the center mark in the X and Y directions on the document is located on this center line. do.

After the alignment of the original is blurred, a tape or the like is pasted along the outer periphery of the text portion of the original image imaged on the index plate 24, such as characters. It is sufficient that there is at least one mark made of tape or the like in each of the X direction and the Y direction. Next, an image of the first original document that has been aligned is taken on a piece of film held on the platen 20. When photographing, first close the shutter provided at the position of the imaging lens 16, move the movable mirror 18 onto the optical axis of the lens 16,
The shutter is opened for a predetermined number of seconds and then closed. At this time, the platen 20 is positioned at a predetermined position in the X and Y directions, and the image of the document is imprinted on the film piece at a predetermined position.

When photographing the next document, the illumination light source on the document side is turned off, the movable mirror 18 is retracted from the optical axis of the imaging lens 16, the illumination box body 30 is closed, and the illumination light source on the index plate 24 side is turned on. The image of the index 24 is projected onto the document table 11 via the imaging lens 16 and the mirror 14. Therefore, on the document table 11, the center line in the orthogonal direction marked on the index plate 24 and the index plate 2
The mark attached to 4 will be projected. Then, next, the manuscript table
Place the next original on top, and align the original so that the outer periphery of the text portion of this original aligns with the mark. Note that the X and Y positions of the original are placed on the center line in the orthogonal direction projected onto the original table 11.
The document can also be aligned by aligning the marks indicating the center of the direction, but in this case, it is necessary to align the document at a total of four locations on the left, right, front, and back.

On the other hand, since positioning using the above-mentioned marks only needs to be performed at two locations, rapid positioning can be performed.

Once the alignment of the document is completed, an image is taken on the document on the film piece on the platen using the procedure described above. Thereafter, by repeating the operations of projecting the image of the index plate 24 onto the document table 11, aligning the document according to the above-mentioned procedure, and then photographing this on a piece of film, you An image of the original can be captured on a piece of film. In addition, by moving the platen 203X and Y-direction moving device 46 by a predetermined amount each time one document is photographed, images of a large number of documents can be photographed in a predetermined order on one sheet of film. Ru.

The mirror 14 can be moved in the horizontal direction by the rotation of the feed screw 36, which allows the mirror 14 to move between the document table 11 and the imaging lens 1.
It is possible to convert the magnification by converting the distance from 6. Further, the imaging lens 16 is similarly movable in the horizontal direction, and it is possible to adjust the focus shift due to zooming and to perform other focal adjustments.

According to the above embodiment, since the image of the original on the horizontally arranged original table is formed on the film piece on the platen through two mirrors, the platen is also arranged horizontally, and the original is placed horizontally. Compared to conventional prepress cameras in which the stand and platen are arranged vertically, this camera has the advantage that it is easier to handle originals and film as a photosensitive material. In addition, the optical path from the document table to the platen is detoured upward by using two mirrors, and in order to obtain a certain optical path length, the dimensions of the entire camera in the front, rear, left, and right directions are reduced, making it more compact. There is also the advantage of being able to Furthermore, although the use of two mirrors is not particularly new in other fields, since two mirrors are used, there is no inversion of the image; for example, when creating a negative plate, the image of the original is inverted. It is also possible to meet the request for imprinting on the film 11 without any printing.

Furthermore, according to the above embodiment, it is only necessary to align the document with the image of the index plate projected onto the document table as a reference, and there is no need to form holes, notches, etc. for alignment in advance on the document. This has the effect of simplifying the printing plate production process.

Although not directly related to the gist of the present invention, according to the above embodiments, by controlling the stepping motors of each part with a computer or other means, everything from setting the film on the platen to setting the film in each area is controlled. A series of operations, from imprinting a document to development, can be performed fully automatically in a bright room under the instructions of a single operator on the operation side.

In this regard, according to each camera described in the above-mentioned US patent specifications,
Most of the work is done by hand, and moreover, the film must be handled in a darkroom, so there are problems in that the work is inefficient and requires skill.

Next, another embodiment of the prepress camera according to the present invention will be described with reference to FIGS. 2 to 4.

In FIGS. 2 to 4, the document table 111 is disposed horizontally with a portion thereof embedded in the upper end of the camera housing 152, so that the document can be placed on a horizontal surface. As shown in FIG. 4, diagonally above the document table 111 is an illumination light source 112 for illuminating the document on the document table 111.
is located. Above the document table 111, the document table 1
Mirror 114 that bends the reflected light from the original on 11 to the side.
is placed diagonally. The mirror 114 is a holder 134
The holding body 134 is screwed into the feed screw 136. The holder 134 is guided movably in the direction of the feed screw 136 by suitable guide means, but non-rotatably around the feed screw 136. The rotation of the feed screw 136 is controlled by a stepping motor or the like.

An imaging lens 116, a movable mirror 118, and an index plate 1 are on the optical path of reflection of light from the document table 111 by the mirror 114.
24 are arranged in this order. The imaging lens 116 is held by a holder 138. The holder 138 is screwed into the feed screw 140. It is assumed that a shutter for opening and closing the optical path is attached to the holder 138.

The holder 138 is connected to the feed screw 140 by an appropriate guide means.
It is guided so as to be movable in the direction, but non-rotatably around the lead screw 140. The rotation of the feed screw 140 is controlled by a stepping motor or the like.

A platen 120 is provided horizontally within the camera housing 152. The platen 120 is an X and Y moving device 1
46 allows movement in the X and Y directions within one horizontal plane. Such movement in the X and Y directions is performed by rotationally driving a feed screw (not shown) by a stepping motor or the like.

A mask plate is arranged in front of the platen 120, and near the platen 120, there is a device that automatically cuts a roll film and conveys a film piece onto the platen.
A device for feeding the photographed film F to a developing machine is arranged, but these devices are not shown because they have no direct relation to the present invention.

The movable mirror 118 is rotatably supported around a predetermined axis, and as shown by the solid line in FIG.
16 and bends the optical axis of the imaging lens 116 downward, and a state where it rotates downward and retreats from the optical path of the imaging lens 116 as shown by a chain line 118A in FIG. You can take the rank. When the movable mirror 118 extends onto the optical axis of the imaging lens 116, this lens 116
bend the optical axis toward the platen 120. An index plate 124 is arranged on the optical axis of the lens 116 in a state where the movable mirror 11g is retracted from the optical axis of the lens 116. The index plate 124 is arranged at a position conjugate with the surface of the platen 120 with respect to the movable mirror 11g. Index board 1
As shown in FIG. 3, center lines 132 are marked on 24, which are orthogonal to each other along the X and Y directions. The indicator plate 124 can be covered with a lighting box body 130. By rotating the illumination box 130 about an appropriate axis, the indicator plate 124 can be opened and closed. Lighting box body 13
0 includes an illumination light source 128 for illuminating the index plate 124.
A mirror 126 is provided to reflect the illumination light from the light source 128 toward the index plate 124.

The difference in the configuration up to this point from the embodiment shown in FIG. 1 is 1M.
Turn the feed screw 136.1 so that the mirror 114 on the manuscript table 111 is higher than the mirror 118 on the platen 120 side.
40 is vertically inclined by an angle θ with respect to the horizontal line. The optical axis of the imaging lens 116 is also inclined by an angle of 0 so as to be parallel to the feed screws 136 and 140. The inclination angle of the mirror 114 and the movable mirror 118 is set to such an angle that the optical axis center line from the H abutment 111 to the mirror 114 and the optical axis center line from the platen 120 to the mirror 118 are both perpendicular.

When the movable mirror 118 extends onto the optical axis of the imaging lens 116, an optical system for imaging the document on the document table 111 relative to the platen 120 is formed. On the other hand, movable mirror 1
18 is retracted from the optical path of the imaging lens 116,
By turning on the illumination light source on the document side and turning off the illumination light source on the index plate 124 side, an optical system for imaging the document on the index plate 124 can be formed. By turning on the illumination light source on the plate 124 side, an optical system for projecting the index plate 124 onto the document table 111 can be formed.

As shown in FIG. 3, a platen 120 is provided in the housing 152, indicated by a solid line, for receiving and taking a film F as a photosensitive material from a film cartridge 156, and for sending the photographed film F to a developing device 182. The housing 152 can be moved horizontally from a substantially central position such as this to a corner of the housing 152 as shown by a chain line 120A. Further, the platen 120 is placed in the housing 152 so that images of the original can be sequentially photographed at predetermined positions on the film F.

It can move in the Y direction. When the platen 120 moves to the corner of the housing 152, the platen 12
The document table 111 and the platen 120 are arranged close to each other so that the document platen 111 reaches below a part of the document table 111. This arrangement was made possible by tilting the optical path vertically so that the mirror 114 side is higher than the movable mirror 118 side, and by calculating the actual optical path length with respect to the planar distance between the mirrors 114 and 118. By making the mirror 114 longer and placing the mirror 114 at the top, it is easier to ensure the optical path length between the document table 111 and the mirror 114. This is the result of making it possible to place 120 units at a lower level.

Since the operation of the embodiment shown in FIGS. 2 to 4 is the same as that of the embodiment shown in FIG. 1, a description of the operation will be omitted.

As described above, according to the embodiments shown in FIGS. 2 to 4, the optical path is tilted vertically so that the mirror above the document table is located at the upper position, and as a result, the document table and the platen are aligned with each other. A predetermined optical path length can be ensured even if the parts are brought closer together to the extent that they overlap vertically, thereby making it possible to provide a more compact plate-making camera.

(Effects of the Invention) According to the present invention, since the image of the original on the horizontally arranged document table is formed on the photosensitive material on the platen through two mirrors, the platen can also be arranged horizontally. This has the advantage that originals and photosensitive materials can be handled more easily than conventional prepress cameras in which the original table and platen are arranged vertically. In addition, the optical path from the document table to the platen is detoured upward by using two mirrors, and in order to obtain a certain optical path length, the dimensions of the entire camera in the front, rear, left, and right directions are reduced, making it more compact. There is also the advantage of being able to

Furthermore, since two mirrors are used, there is no reversal of the image, and it is possible to meet the demand for imprinting the original image onto a photosensitive material without reversing it.

Furthermore, if the optical path is tilted vertically so that the mirror above the document table is positioned higher, the distance between the document table and the mirror above it can be increased, and this mirror can be placed near the imaging lens. You will be able to do that. Since the optical path is narrowed at this mirror position, the size of the mirror can be reduced, making it possible to easily manufacture the mirror and obtain a mirror with high precision. Also,
A predetermined optical path length can be ensured even if the document table and platen are brought closer to each other to such an extent that they partially overlap vertically, thereby making it possible to provide a more compact plate-making camera.

[Brief explanation of the drawing]

FIG. 1 is a side view showing one embodiment of the camera for plate making according to the present invention, FIG. 2 is a side view showing another embodiment of the camera for plate making according to the present invention, FIG. 3 is a front view of the same, and FIG. FIG. 4 is a plan view of the same as above. 11.111...Original table, 14,114...
・Mirror 16°116...imaging lens, 18
, 118... Movable mirror 20. 120... Platen, 24, 124... Indicator plate, F... Photosensitive material. Procedural amendment (voluntary)

Claims (1)

[Claims] 1. A document table arranged horizontally on which an original can be placed; a platen placed horizontally on which a photosensitive material can be mounted; and a platen placed above the document table. a mirror that reflects light from the original platen to the side; an imaging lens disposed on the optical path reflected by the mirror; a movable mirror that bends the optical axis of the lens toward the platen in a state in which it extends onto the optical axis of the lens; and a movable mirror that is on the optical axis of the lens in a state that it is retracted from the optical axis of the lens; A plate-making camera comprising an index plate disposed at a conjugate position with the platen. 2. The optical path from the mirror above the document table, through the imaging lens, to the movable mirror, and further to the index plate is inclined in the vertical direction so that the mirror side above the document table is in the upper position. The camera for prepress mentioned above.