JPH01196066A - Exposure device - Google Patents

Abstract

PURPOSE:To obtain a small-sized, stable, and to secure a light source filter device for scan exposure by providing a filter holding device rotatably and positioning a shield part oppositely to a slit opening part in a stand-by time after a lamp lights. CONSTITUTION:A prism 301 is provided rotatably by constituting the filter holding device by arranging filters of B, G, R, ND, etc., on its respective prism surfaces 301A, and some prism surface 301A and a transmission window 304 face a contact exposure surface. Then the respective filters 301B are held on a frame and fitted in windows bored in the respective prism surfaces 301A in parallel to a rod-shaped light source lamp, thus constituting the filter holding device. One prism surface 301C is positioned oppositely to the transmission window 304 of the prism surface when the exposure part lights and stops while the window is closed with a non-transmission material 301D and a document is not scanned, thereby preventing the filters from deteriorating in performance. Consequently, the color separation filters are prevented from deteriorating in performance, the size is reducible, and the operability is improved.

Description

[Detailed description of the invention] [Industrial application field]

In the present invention, a separation mesh original for printing, which has been developed and finished after spectral exposure, is placed accurately in a predetermined position and exposed multiple times to a positive color or negative color photosensitive material, once for each original, resulting in the same print finish. This invention relates to an improvement in an exposure device, which is a technology for directly inspecting the presence or absence of abnormalities in a final document for making color image copies and printing plates.

[Conventional technology]

Conventionally, exposure devices illuminate the document surface with light from a light source, magnify it,
There are two methods: a method in which an image is formed on a photosensitive material using a projection lens with a function of reducing or equal magnification, and a method in which an original and a photosensitive material are overlapped and irradiated with light from a light source for close exposure. Furthermore, there are two methods of irradiating light from a light source: scanning exposure and static exposure. The former uses a relatively small light source to create a compact exposure device, while the latter generally uses a relatively high-brightness light source and In order to achieve parallelism and uniformity, the distance from the light source to the exposure surface is large, so a large exposure device is required. In the field of printing plate making, the process from continuous tone images such as reversal film, color negative film, and paper to creating printing plates consisting of images consisting of halftone dots uses a large amount of film to separate colors. , image composition, etc. Therefore, the work becomes complicated, and the characters,
Many mistakes occur, such as incorrect layout. Furthermore, since the client (orderer) requests changes in text such as prices, layout changes, color changes, etc., it is easy to forget to make changes. It is also necessary to check in advance whether the printed matter will be finished in the desired color tone and gradation. These are collectively called proofreading. For this reason, various systems including trial printing called proof printing have been announced and sold for the purpose of these checks. Examples include those using CRT, those using non-silver salt photosensitive materials such as photopolymers and diazo, those using dry toner, and electrophotographic methods. However, these calibration systems generally require a long time to calibrate one sheet, and have problems such as high material cost and poor workability, and have not been a system that is sufficient for practical use. On the other hand, as another method of obtaining a proof, there is a method of printing a separation mesh original onto a color photosensitive material using color-separated light. For example, JP-A-62-280746, JP-A No. 62-28074
No. 7, No. 62-280748, No. 62-280749
No. 62-280750, No. 62-280849, No. 60-42760, etc., describe a method of obtaining a calibration material on a color photosensitive material using a photographing system using a projection lens. Although these devices are large, they are so-called "bright room specifications" that allow work to be carried out in a normal room, and the exposure operation can be performed in a dark room while the photosensitive material itself remains inside the device. It can be done with a regular knife. Therefore, it is possible to perform color calibration easily, in a short period of time, and at low cost, and it has better characteristics than other calibration systems. However, since it is a photographic system, effects such as lens flare occurred, and there was a deterioration in gradation reproducibility. That is, due to flare etc., the small dots of the net tend to fly off and the large dots tend to collapse. On the other hand, as another method for similarly obtaining a proof material using a color photosensitive material, Chesley F, Carlson Co.
The Carlson Proofm from mpany
aster System, Kreonite. Inc., Co1or Proofing Sys.
There is a contact exposure method sold under the name TEM. These methods involve exposing a color light-sensitive material to a separation mesh original in direct contact with the light-sensitive material, so they are greatly improved in terms of gradation reproducibility compared to photographic methods. On the other hand, since color photosensitive materials have a photosensitive region in the entire visible range, they cannot be handled in a bright room.
This method had the disadvantage of forcing the user to grope his way inside the darkroom.

[Problems to be solved by the invention]

As mentioned above, when exposing each printing plate original to the same color photosensitive material multiple times, there are two methods: projecting with a lens and contact exposure, but the latter has better reproducibility of halftone dots and tones. good. However, although contact exposure has good quality performance, workability is poor if it involves operations in a dark room as in the past. Furthermore, the manuscripts and photosensitive materials used are large-sized, and if the light source used was a static exposure structure, it would be extremely large, making it extremely difficult to operate and requiring a large installation space, making it uneconomical. be. Therefore, in order to achieve miniaturization in addition to the desire for a bright room, it is necessary to change the static exposure to scanning exposure and make the moving light source head smaller. Furthermore, in order to perform multiple exposure, filter conversion for color separation exposure must be performed each time. The attachment of the filter and the conversion device are generally carried out by sliding a color separation filter fitted into a frame at the exposure window of the lamp house of the light source. If a strip-shaped filter is slid in the direction of the short side of the bar-shaped light source, it becomes relatively compact, but the sliding performance with respect to the guide rail is not smooth. Conversely, if it is slid in the long side direction, the sliding performance is smooth, but the sliding space for insertion becomes too long. Further, such a filter is sensitive to heat, and when exposed to repeated lamp irradiation, its quality deteriorates, resulting in a change in spectral performance, loss of parallelism of light, and deterioration of image quality. Therefore, it is necessary to take measures to avoid this. SUMMARY OF THE INVENTION An object of the present invention is to solve these problems, to provide an exposure apparatus having a compact, stable and reliable light source filter device for scanning exposure, and to improve the efficiency and workability of a color proof production apparatus.

[Means to solve the problem]

The purpose is to rotate a filter holding device having at least one filter and a shield across the exit optical path of the exposure means, which consists of a bar-shaped lamp and is configured such that the emitted light exits through a slit-like opening. This is achieved by an exposure apparatus characterized in that a control means is provided so that the shielding part is positioned opposite to the slit-shaped opening part during a standby time after the lamp is turned on.

【Example】

A color proof production apparatus equipped with the exposure apparatus of the present invention will be explained with reference to a front view in FIG. 1, a side view in FIG. 2, and a top view in FIG. 3. However, the present invention is not limited to this example. Before creating the actual printing plate using each color-separated original film that has been color-separated into 0, M, Y, and black versions, the color proofing device checks to make sure there are no mistakes in the layout of the original film and that the colors are different. This device is used to check whether there are any errors or typographical errors, and to obtain proofs to confirm the finish of printed matter in advance.The device positions one or more of the above-mentioned decomposition film and exposes it to color light. By creating a proof using color photosensitive material by superimposing a large amount of close exposure on the material, it is possible to discover errors in the separation screen manuscript, check the print finish in advance, and take action to correct the separation screen document. It is something. The main body part 100 includes an original platen 14 having an upper surface 141 and a lower surface 142 for installing an original positioning binper 143 on the upper side of the main body 7 frame 101 supported by leg parts -102.
0, and a light-shielding cover 120 is provided above the light-shielding cover 120, which can be opened and closed to form a dark room as a first room. Further, an exposure section 300 for scanning and exposing the contact exposure surface of the document table is provided in the first chamber. At the center of the exposure section, one or more (three in this embodiment) rod-shaped light source lamps 302A are installed.
, 302B, and 302C are fixed to a housing 316, and are surrounded by a drum-shaped column 321, which has a reflective mirror surface 306 in its internal cavity, has a transparent window 304 in a part, and is also fixed to the housing 316. It is provided. Then, on the outside of the drum-shaped column, a hollow polygonal column (hexagonal column in this embodiment) 301 is arranged concentrically at the center, and filters B, G, R, ND, etc. are provided on each columnar surface 301A. The filter holding device is arranged so as to be rotatable. Also, any of the above pillar surfaces 30! A and the transmission window 304 are arranged to face the contact exposure surface. Each of the filters 301B is held by a frame and fitted into a window formed in each columnar surface 301A parallel to the rod-shaped light source lamp, thereby forming a filter holding device. Further, one of the columnar surfaces 301C faces the transparent window 304 of the columnar surface when the window is covered with an opaque material 301D and the exposure section is lit and stopped without scanning a document. This position prevents deterioration of filter performance. And on the outside of the polygonal column there is a shielding plate 308, a solenoid 312 for operating it, a return spring 314, and an exposure window 31.
0 is provided. The exposure unit 300 can run smoothly on the rails 317A and 317B for scanning. In addition, each of the B, G, R, and N D filters fitted to each of the columnar surfaces must have an appropriate density according to the spectral sensitivity of each photosensitive material, and in order to correspond to special ones. It is useful to set a filter whose color density has been changed on a preliminary column surface. In an exposure apparatus that requires one or two specific filters, it is possible to use a triangular prism filter holding device with a shielding cylindrical surface, and the filter holding device only needs to be a polygonal prism. As described above, by incorporating the light source filter device for scanning exposure of the present invention, the exposure section 300 is miniaturized, and the light shielding cover 120, which is covered to form a dark room during scanning exposure, is also miniaturized, and the workability of opening and closing operation thereof is improved. The task of placing documents and switching between automatic scanning and exposure has become much easier, the life of the filter has been extended, and the filter can now be used stably for a long time. Furthermore, the image forming performance by multiple exposure is stable, and the installation space of the entire color proof production device can be reduced. Inside the main body 7 frame 101, a sensitive material mounting section 200 is provided as a second chamber. And the sensitive material mounting table 201 is
It is driven by a motor 214 and can be moved up and down. On the other hand, an endless light-shielding curtain 242 is used as a light-shielding member.
are applied to rollers 241, 242A, 243, 244, and an open window having a size at least larger than the cross section of the moving area of the photosensitive material mounting table is formed in the substantially middle part of the long portion. In such a light shielding member 240, the lower surface 142 of the document table is
By running the light-shielding belt on a slightly lower surface, that is, the boundary area between the first chamber and the second chamber, the light-sensitive material mounting table 20
It is provided so that the formation and release of light tightness from the second chamber in which the first chamber is housed to the first chamber can be switched. The light-shielding belt 242 can move only when the photosensitive material mounting table is lowered to a position where it does not touch the light-shielding belt, which is a light-shielding member.The light-shielding belt 242 can only move up to the document position when the light-shielding curtain is opened. Only when you are Further, a long roll 402 of silver halide color photosensitive material is loaded into a magazine 401 to form a photosensitive material loading section 400. They are lined up and waiting. Then, the tip is further fed to the left end of the fixed base 527 by the pinching roller 511, the tip is sucked by the suction cup 523, and the traveling head 522 having the suction cup guides the rollers 525 and 526 to the traveling rails 521 on both sides. The measuring device moves to a position where a predetermined length of the photosensitive material is measured and stops. The photosensitive material is cut by a cutter 510 and further moved so that the leading end of the photosensitive material is positioned at a predetermined position on the photosensitive material mounting table 201. After the suction of the suction cup of the traveling head is removed, the traveling head 522 returns to its original position. Here, a solenoid 535 is attached to both sides of the traveling head 522 via a bracket 534, and its movable iron core 53
A frame 531 is fixed to 6, and the traveling head 522,
A suction cup 5 coupled to the hose 524 on the frame 531
23 is attached, and the holding pipe 537 of the suction cup is provided penetrating through a guide hole drilled in the head and the 7th frame, fixed to the frame in the thrust direction, and slidable along the hole to the head. It floats above the exposure table surface via a helical spring 532 that is installed between the traveling head 522 and the frame 531. When the solenoid is energized and the suction valve is opened, the suction cup descends to attract the photosensitive material, and then when the solenoid is de-energized, the suction cup is lifted up and the photosensitive material is conveyed. When the photosensitive material is transported and placed on the photosensitive material mounting table 201 in this manner, the blower 204A is driven via the flexible hose 205 to apply intermittent pressure to the suction holes made on the photosensitive material mounting table. The photosensitive material is tightly fixed on the photosensitive material mounting table. This tightly fixed state is maintained until multiple exposures are completed and the photosensitive material begins to be transported to the developing section. Furthermore, in this state, the light-shielding curtain 24°2 is in the light-shielding position, so that the second chamber where the photosensitive material mounting table is located remains in a state where a dark room is formed. Here, the first room is illuminated with outside light by passing through the upper light-shielding cover 120, and placed in a resist bin (pin bar) 143 set on the top surface 141. One of M or C black version,
(or several or all of these) are inserted so that most of the original is placed on the light-shielding screen. In this state, the light-shielding cover 120 is closed to make the first room a dark room and light-tight, and after the light-sensitive material mounting table is raised slightly below the surface of the light-shielding curtain belt, the light-shielding curtain belt 242 is moved to open it. The circuit is configured so that the light-shielding belt 242 does not move to open unless the light-shielding cover is completely closed. Then, in a state where both the first room with the upper surface of the document table and the second room with the photosensitive material placement table become a common dark room, the photosensitive material placement table 201 is raised to match the exposure surface, that is, the separation screen original reference surface. At this time, the airtight gasket 201c provided on the abutting surface around the photosensitive material mounting table in the second chamber is pressed against the document table 1 in the first chamber.
40, and the gap created by the insertion surface of the photosensitive material mounting table into the opening forms a suction channel groove 204.
In addition, airtightness is maintained between the document table surface, the photosensitive material mounting table surface, and the document sandwiched between the transparent cover sheet and the photosensitive material. That is, a transparent cover sheet roll 274 is wound around a shaft 273, and its tip passes through a squeeze roller 276 and is stopped by a stopper 272.
71 is guided by rails 281A and 281B and moves to the right in FIG.
The cover sheet 275 to be unwound is pressed by a spring 278 and the squeeze roller 2 is rotatably fixed to a shaft 277.
7G, the original and the photosensitive material are covered with a cover sheet, and when the head reaches the right end of the original platen and is lowered below the top surface of the original platen so as not to obstruct the movement of the exposure section, the blower 206 is activated. Suction hose 2
07, the air interposed between the exposure table, the upper surface, and the cover sheet is sucked through the flow path groove 204, and the photosensitive material, each document, and the cover sheet are stacked and held in close contact with each other in a planar shape. . Note that the squeeze roller 276 is not provided in the cover sheet device, but is provided at the lower part of the exposure section 300, and the same effect is obtained. At this time, as shown in FIG.
The dimensional relationship between the abutting surface 201b, the airtight packing 201c attached thereto, and the lower surface 142 of the document table t4o is adjusted so that the upper surface 201a of the photosensitive material mounting table 201 is on the same plane. By doing this, air can flow smoothly between the transparent cover sheet, the document table and the photosensitive material mounting table through the flow channel grooves, and the cover sheet, document and photosensitive material can be placed in the correct flat shape. Close contact is achieved. Further, the sensitive material mounting table may be located at a slightly lower position than the document table. In this state, the exposure section 300 is connected to the guide rail 317A.
, 317B to perform scanning exposure, and complete the first color exposure using the filter. Next, in order to perform a second image exposure using a filter of a different color, the cover sheet is returned to its original position and the photosensitive material mounting table is lowered to a position slightly below the travel path of the light-shielding curtain, and air is blown there using the nozzle 215. By switching the blowing side of the blower 206 to blow air into the flow path groove 204 and closing the light shielding curtain, the original and the photosensitive material can be easily and completely separated. The blowing by the blower and the lowering of the photosensitive material mounting table may be performed in the reverse order or at the same time. and light shielding cover 120
When the first room is opened, the first room becomes a bright room, but the second room is light-dense compared to the first room, forming a dark room. In this state, place the second original (black version and one of Y, M, C, e.g. M version, or any one of Y, M, C black version, or several or all of these) into the resist bin. After placing the light-shielding cover on the plate, open the light-shielding curtain and raise the photosensitive material mounting table to the surface of the document table. Cover the cover sheet again and apply suction to make each sheet stick together, turn the polygonal column 301, and separate The cylindrical surfaces provided on the filters are made to face each other, and scanning contact exposure is performed using a second color filter to complete the second exposure. Similarly, the third manuscript (black version and one of Y, M, C, e.g. 0 version, or any one of Y, M, C black version, or several or all of these) and Exposure using the corresponding filter is also performed in the same procedure to complete the third exposure. In this way, exposure is repeated one to several times as necessary. Before these exposures, after exposure and before exposing a set of separation screen originals, or during several color separation exposures for a set of separation screen originals, the light source lamp is turned on. During the standby time, the shielding part is positioned opposite the slit-like opening. During spectral exposure, if the waiting time is extremely short, it is possible for the shielding part to be positioned without facing the slit-shaped opening.
In order to prevent performance deterioration of the color separation filter, it is preferable to position them facing each other. Finally, the photosensitive material mounting table is lowered to the lowest position, the suction is released to release the photosensitive material, and the tip of the photosensitive material is fed to the nipping roller 552 by a device (not shown). The photosensitive material whose tip has reached the nipping roller 552 is guided by the guides 561, 562, 563, 56 of the conveyance chute section 550.
4.565 and switching chute 566 and guide roller 5
After being sent downward by
By switching around 68, the sheet is conveyed by guide rollers 556, 557, 558, and 559 between guides 564.565.degree. When an internal latent image type direct positive sensitive material is used, during transportation in the color developing tank 601, the exposure lamp 351, filter device 352, reflector plate 353, 354, etc. of the second exposure section 350 are used. Exposure window 35
Fog exposure is performed by an exposure box 356 consisting of 5 parts. The photosensitive material then passes through a bleach-fixing tank and a stabilizing tank, is dried while being slowly transported through a drying section 680 by transport rollers 681 and 682, and is collected at the right end of the apparatus after being developed. It should be noted that as soon as the exposed photosensitive material begins to be conveyed through the conveyance chute section 550, the subsequent photosensitive material is transferred to the photosensitive material mounting table 2.
The process of being conveyed onto 01, measured, cut by cutter 510, and set in close contact is repeated as described above. When using an internal latent image type direct positive, the photosensitive material is the second
Although exposure is necessary, when using a negative color photosensitive material or a solarization type direct positive photosensitive material, the second exposure is not necessary and the light remains off. In addition, when using other dye-bleached color photosensitive materials, color reversal photosensitive materials, diffusion transfer photosensitive materials, etc., it is possible to perform exposure and development processing in the same system by providing processing baths suitable for each type of material. . Of course, for exposure to direct positive light-sensitive materials or reversal color light-sensitive materials, a black plate is overlaid on each Y, M, and 0 version of the manuscript, and B, B, and
The GSC plate and the black plate are exposed to light three times with corresponding R filters for the M plate and the black plate, but when it comes to exposure for negative color photosensitive materials, each Y plate and M plate are used for the exposure of the negative color photosensitive material. ,
Stack the 0 version manuscript individually and add B for Y version, G for M version,
The 0 version is exposed three times with an R filter overlaid, and then a black version is overlaid for the fourth time, and an ND filter is applied, and if necessary, a color filter for color correction is applied, and exposed. Furthermore, if necessary, in addition to the above-mentioned separate color exposures, further exposures using light corresponding to different color separations may be added to produce basic colors suitable for the printing ink. Furthermore, in order to blend lights corresponding to different color separations in advance, processing such as blending BGH colored light or exposing using a combination of filters may be performed. Similarly, repeated exposure,
Alternatively, a blend of colored lights or a combination of filters may be used. In this case, depending on the case, it may be necessary to use a decomposition film called a special color film, or to combine the outer film and the special color decomposition film, and in some cases, it may be necessary to stack several sheets of other decomposition film. It is necessary to perform contact baking. Note that the photosensitive material in the exposed area once enters the guide chute 565 and is then turned over and enters the developing device with the emulsion side facing up; however, it can also be placed into the developing device without entering the guide chute 565 by making a knee turn. However, when using an internal latent image type direct positive photosensitive material,
The light source position for the second exposure must be placed above the developing device and below the photosensitive material transport path, which makes maintenance and installation somewhat difficult.An exposure window must be opened on the side of the developer tank, and the liquid This is not very desirable as it is difficult to clean. There are two types of photosensitive materials: those with high sensitivity and those without. When using a photosensitive material with low sensitivity, the exposure area 30
A plurality of light source lamps of the 0 polygonal column 301 may be provided and a large number of them may be turned on to make the exposure more powerful. In addition, by using the measures of lowering the scanning speed and the measures of making the opening/closing of the exposure window 310 variable, in combination or alone, it is possible to perform high-quality exposure without worsening the reciprocity law failure condition.

【Effect of the invention】

As described above, by incorporating the light source filter device for scanning exposure of the present invention, it is possible to prevent deterioration of the performance of the important color separation filter, improve the life of the filter, and furthermore, it is possible to downsize the exposure section 300. The light-shielding cover 120 used to form a dark room during scanning exposure is also made more compact, improving the workability of its opening and closing operations, allowing for quick document placement in a bright room and rapid switching to automatic scanning exposure in a dark room. sure, safe,
It becomes easier and the entire color proofing device becomes smaller.
This has greatly improved the image quality of proofs (color proofs) and the workability and efficiency of proofreading.

[Brief explanation of the drawing]

FIG. 1 is a front view of a color proof production device equipped with an exposure device of the present invention. FIG. 2 is a side view of the exposure apparatus of the present invention. FIG. 3 is a top view of the color proof production apparatus shown in FIG. 1. FIG. 4 is a side sectional view showing the positional relationship between the document table and the photosensitive material mounting table. 100...Color proof creation device main body 120
..... Light-shielding cover 140 .... Document table 141 .... Top surface 142 .... Bottom surface 200 ..... Sensitive material placement section 201 .... Sensitive material placement table 201a...Top surface 201b
...Abutting surface 201c...Airtight gasket 204...Suction channel groove 215...Nozzle 240...
- Light shielding members 241.242A, 243.244...
...Roller 242...Shading curtain belt 270...Cover sheet device

Claims (1)

[Claims] A filter holding device having at least one filter and a shield is rotatably provided across the exit optical path of the exposure means, which is a rod-shaped lamp configured such that the emitted light is emitted through a slit-like opening; An exposure apparatus characterized in that a control means is provided so that the shielding part is positioned opposite to the slit-shaped opening part during a standby time after the lamp is turned on.