JP2001277464A - Laser exposure device for plate-making - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser exposure device for plate-making wherein an exposure can be performed in such a manner that by using a large number of semiconductor laser beams and optical fibers, a large number of laser beams are overlapped by a precise pitch in order under a linked chain form for the exposure. SOLUTION: Regarding a set of optical fiber passing-supporting sections 7a, 7a and so forth of a diagonal arrangement, which are formed on a tip end side bracket 7 at the end section closer to an optical lens system of the optical fiber, a pitch P1 to be shifted in the surface longitudinal direction of a roll to be made into a plate is 1/2 to approximate 3/5 of the beam diameter of the laser beam entering the optical lens system 4. Also, a pitch P2 to be shifted in the circumferential direction of the roll to be made into the plate is separated by a proper dimension in a manner to keep the bracket strength. Also, a pitch P3 to be shifted in the surface longitudinal direction of the roll to be made into the plate of the diagonal arrangement line of the set of the optical fiber passing-supporting section is a value obtained by multiplying the pitch P1 by the number of the optical fiber passing-supporting sections of the set.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plate-making laser exposure apparatus for plate-making, wherein a large number of laser beams are arranged so as to be overlapped one after another using a semiconductor laser so that a large number of beams can be exposed.

[0002]

2. Description of the Related Art Japanese Patent Application No. 4-1 filed by the present applicant.
No. 96499 uses a large number of semiconductor lasers, and a large number of laser beams are arranged in a line so as to be overlapped one after another, so that multiple beam exposure can be performed.

[0003]

However, it has been difficult to irradiate the lens by arranging the light radiating from the end face of the optical fiber and spreading so as to be successively overlapped in a line with the same light diameter. Since the laser beam emitted from the end face of the optical fiber does not have the spread of drawing,
They could not be overlapped in a chain.
Further, in a configuration in which laser beams are arranged one after another so as to be overlapped one after another and irradiated onto a lens, the number of laser beams cannot be increased much.

The present invention has been devised in view of the above-mentioned point, and it is possible to superimpose a large number of laser beams one after another in a line by using a large number of semiconductor lasers and optical fibers, and to arrange the laser beams in the arrangement direction. It is an object of the present invention to provide a plate-making laser exposure apparatus capable of performing irradiation with a large number of laser beams by irradiating in a direction perpendicular to the direction of the laser beam.

[0005]

According to the present invention, a required number of semiconductor lasers and optical fibers are provided in the same number (6 in the figure).
4) The laser light emitted from each of the semiconductor lasers is passed through the corresponding optical fiber, and the laser light emitted from all the optical fibers is incident on the optical lens system so as to form a linear array. A configuration in which a laser beam squeezed while maintaining a linear array is applied to a plate-making roll rotating at a constant speed, and an end of the optical fiber near the optical lens system is formed on a tip side bracket. It is fixed to the optical fiber insertion support,
The required number of optical fiber insertion supports are provided in parallel with the required number of diagonal arrangements as one set. For one set of optical fiber insertion support parts of the diagonal arrangement, the pitch P1 is shifted in the surface length direction of the plate making roll. Is a pitch P that is 1/2 to about 3/5 of the optical diameter of the laser light incident on the optical lens system from the optical fiber, and is shifted in the circumferential direction of the plate making roll.
2 is a plate-making plate having an appropriate distance so as to maintain the strength of a bracket for fitting and fixing an optical fiber, and a diagonal arrangement line of a pair of optical fiber insertion support portions and an oblique arrangement of an adjacent pair of optical fiber insertion support portions. Wherein the pitch P3 shifted in the direction of the surface length of the roll is a product of the pitch P1 shifted in the direction of the surface length of the plate making roll and the number of a set of optical fiber insertion supports. An apparatus is provided.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A plate making laser exposure apparatus according to an embodiment of the present invention will be described with reference to the drawings. The plate-making laser exposure apparatus of this embodiment has a
Semiconductor lasers 1, 1,... And optical fibers 2, 2,.
.. Are provided in the required number, and the laser light emitted from each semiconductor laser 1 is passed through the corresponding optical fiber 2 via the condensing lens 3 attached to each semiconductor laser 1, and all the optical fibers 2, 2,. The laser beam emitted from the optical lens system 4 is configured so that the incident array on the optical lens system 4 forms a single-chain arrangement, and the laser light narrowed down while maintaining the single-chain arrangement by the optical lens system 4 is rotationally driven by a motor. Irradiation is performed on a plate-making roll R that is chucked at both ends by a driven-side chuck cone and a tail chuck cone that is movable close to and separated from the plate, and rotates at a constant speed.

The required number of semiconductor lasers 1, 1,... Are divided into a required number of sets as one set (in the figure, eight sets are divided into eight sets as one set). Are substantially stacked (eight layers are stacked in the figure), and all sets of semiconductor lasers are arranged in parallel (8 in the figure).
Row) and a bracket 5.

The optical fiber 2 has an end near the semiconductor laser fixed to a base end bracket 6.
Also, the end near the optical lens system is a tip side bracket 7.
It is fixed to. The base end bracket 6 and the distal end bracket 7 are each formed with a single plate with a hole through which an optical fiber can be forcibly inserted, and the hole is formed by the optical fiber insertion supporting portion 6a,
7a, the end of the optical fiber 2 is fixed.

As shown in FIG. 2, the proximal end bracket 6 and the distal end bracket 7 are provided with fixing means capable of firmly fixing the end of the optical fiber 2 and capable of adjusting a slight inclination. I have. The fixing means is screwed with a bush 8 having an external surface formed into a male screw and an internal surface formed into a conical surface having an annular step, and is compressed as the screwing of the bush 8 is made deeper. And a clamping piece 9 for fixing the optical fiber 2 by generating a clamping force on the optical fiber 2 so as to engage with the annular step of the conical surface of the bush 8 so as to be fixed. And an angle adjusting wedge 10. One or more angle adjusting wedges 10 are attached as necessary. The outer peripheral surface of the angle adjusting cylinder 9 is formed in a perfect circular cylindrical surface and is in sliding contact with the perfect circular inner peripheral surface of the bush 8.
The end of the optical fiber 2 inserted in close contact with the cylindrical surface whose inner peripheral surface is slightly eccentric can be tilted at an extremely small angle, so that the angle of incidence of laser light on the optical fiber 2 and the angle of emission of laser light from the optical fiber 2 Can be adjusted very precisely. The optical fiber insertion support portions 6a, 6a,... Provided on the base end bracket 6 are arranged to precisely face the laser emission windows of all the semiconductor lasers 1, 1,. The fixing means is attached to each optical fiber insertion support portion 6a. Therefore, the optical fiber insertion support portion 6a
The end of the optical fiber 2 near the optical lens system is precisely opposed to the laser emission window of each of the semiconductor lasers 1, 1,.

As shown in FIG. 3, optical fiber insertion support portions 7a, 7a,.
Are the same as the number of the semiconductor lasers 1, and the required number of diagonally arranged (eight in the figure) is provided as one set, and the required number of sets (eight in the figure) are provided in parallel. For the supporting portions 7a, 7a,.
The pitch P1 shifted in the surface length direction is, as shown in FIG. 4 (a) or (b), 1/2 to about 3/5 of the diameter of the laser beam incident from the optical fiber to the optical lens system. Further, the pitch P2 shifted in the circumferential direction of the plate making roll is separated from the pitch P2 by an appropriate size so as to maintain the strength of the bracket for fitting and fixing the optical fiber. The pitch P3 shifted in the surface length direction of the plate making roll with the diagonal arrangement of the optical fiber insertion supporting portions is the product of the product of the pitch P1 shifted in the surface length direction of the plate making roll and the number of one set of optical fiber insertion supporting portions. Have been.

For this reason, all the semiconductor lasers 1, 1,.
..When laser light is simultaneously emitted from the optical fiber, delay required for the timing of blinking and oscillating laser light in accordance with the arrangement position of the end face of each optical fiber (delay processing by the number of shifted pitches) As shown in FIG. 4, the spot of the laser light incident on the optical lens system 4 so as to be linear in the surface length direction of the plate making roll R is about 1/2 to 1/2 of the optical diameter d1 of the laser light as described above. It can be shifted one after another so as to be 3/5 to form a one-row chain arrangement. Then, as shown in FIG. 5, the laser beam incident on the optical lens system 4 with the light diameter d1 is narrowed down by the optical lens system 4 so as to have the light diameter d2. Further, the timing of repeating the blinking and oscillation of the laser light is shifted one after another so that the pitch P1 '= 1/2 × d2 or 3/5 × d2 even in the circumferential direction of the plate making roll R, and is arranged in a one-row chain. Irradiation.

The tip side bracket 7 fixing at least the optical lens system 4 and the end of the optical fiber 2 near the optical lens system is provided so as not to cause relative displacement with each other. From the position corresponding to one end, the plate making roll R is approached.
When the auto-focus lens close to becomes a distance close to the required distance with respect to the plate making roll R, it stops approaching movement, and then scans in the surface length direction of the plate making roll R, The scanning movement is stopped when it reaches the other end of the plate making roll R, and then separated from the plate making roll R. In the above case, the total pitch (P) of the spots irradiated on the surface to be irradiated with the laser light of all the semiconductor lasers 1, 1,.
Scanning movement is performed by 1 ′ × 64) in the surface length direction of the plate making roll R. Further, the autofocus lens of the optical lens system 4 closest to the plate making roll R is supported by a voice coil or an electrostrictive actuator.
In response to the scanning rotation of a small size (60 μmm max), simple vibration control is performed so that the proximity gap with the plate making roll R is always constant.

Therefore, the plate-making roll R is rotated at a constant speed, and the semiconductor lasers 1 are turned on and off in a blinking manner based on the image data assigned to each of the semiconductor lasers 1. A negative latent image for forming a gravure plate image on a film can be formed, and a positive or flexographic plate image for forming a gravure plate image on a black coat film formed on a plate-making roll R can be formed. To form a negative plate image engraving. That is, the plate-making laser exposure apparatus of the present invention comprises: (1) dechroming treatment-grinding stone polishing-surface activation treatment-nickel plating-copper plating-grinding stone polishing-photosensitive film coating-laser exposure / latent image formation-development / resist It can be applied to a gravure plate-making process in which image formation, corrosion, and chrome plating are performed. (2) It can be applied to a gravure plate making process in which chromium removal treatment, grinding stone polishing, surface activation treatment, nickel plating, copper plating, grinding stone polishing, black film coating, laser ablation / resist image formation, corrosion, and chromium plating are performed. (3) The method can be applied to a flexographic plate making process of performing laser ablation / resist image formation on a black film, overall exposure, black film removal, and development.

The apparatus of the present invention includes an exposure apparatus for offset lithographic printing. Further, in the apparatus of the present invention, the front side bracket 7 has a V-shaped concave portion formed on the upper surface at a pitch P3, a V-shaped convex portion formed on the lower surface at a pitch P3, and a V-shaped concave portion on the upper surface. The V-shaped protrusion is placed on the second and subsequent blocks in which the recesses are formed at the pitch P3, and a gap is secured at the depth end of the fitting between the V-shaped protrusion and the V-shaped protrusion. It is also possible to adopt a block stacking structure in which the optical fiber insertion support portion is used.

The material of the black film that can be laser-ablated includes, for example, flammable substances (nitrocellulose, ethylene vinyl acetate strong polymer, unsaturated polyester resin, epoxy resin, allyl resin, polyurethane resin, polyethylene, polypropylene, polystyrene, Polyacetal,
One or more kinds of natural rubber, etc .: 75% by weight) An oxidizing agent (ammonium nitrate or chloric acid compound: 10% by weight) and a light absorber (carbon black: 15% by weight), capable of laser ablation and etching resistance Is applied to the roll surface so as to have a thickness of several μm.

[0016]

As described above, according to the plate-making laser exposing apparatus of the present invention, a large number of laser beams are sequentially shifted in a row using a large number of semiconductor lasers and optical fibers. A large number of laser beam exposures can be performed by irradiating the laser beams in a direction orthogonal to the arrangement direction of the laser beams that can be overlapped. In particular, according to the plate making laser exposure apparatus of the present invention, the pitch P1 of the optical fiber insertion supporting portions 7a, 7a,. The pitch P2 shifted in the surface length direction of the plate-making roll between the pitch P2 shifted in the circumferential direction of the plate-making roll and the diagonal arrangement line of the pair of optical fiber insertion-supporting portions and the oblique array of the pair of adjacent optical-fiber insertion supporting portions.
If ultra-precision 3 is determined, a large number of laser beams can be chained in a row in combination with an electrical process that delays the timing of the blinking of the laser beam in accordance with the arrangement position of the end face of each optical fiber. It is possible to superimpose one after another at a precise pitch.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a laser exposure apparatus for semiconductor laser plate making of the present invention.

FIG. 2 is an enlarged cross-sectional view of a main part showing a structure in which an end of an optical fiber fixed to an optical fiber insertion support provided on each of a proximal bracket and a distal bracket can be adjusted by a small angle.

FIG. 3 shows the arrangement of the optical fiber insertion support portions provided on the distal end side bracket 7 and the laser light that is successively shifted in the direction of the surface length of the plate making roll R such that the laser beam becomes 1/2 to about 3/5 of the light diameter. The figure which shows the positional relationship which forms a one-row chain arrangement.

FIG. 4A is a diagram illustrating a positional relationship in which laser beams incident on an optical lens system are sequentially shifted so as to have a pitch dimension of 1/2 of the optical diameter and form a linear array. FIG. 3B is a diagram illustrating a positional relationship in which laser beams incident on the optical lens system are sequentially shifted so as to have a pitch dimension of 3/5 of the optical diameter and form a linear array.

FIG. 5A is a view showing a state in which laser light corresponding to a solid image portion on a plate making roll is irradiated by irradiating laser light at the pitch shown in FIG. 4A. (b) shows FIG.
FIG. 7B is a diagram showing a state in which laser beams corresponding to a solid image portion on a plate making roll are irradiated with laser beams at the pitch shown in FIG.

[Explanation of symbols]

1, 1, semiconductor laser, 2, 2, optical fiber, 3 condenser lens, 4 optical lens system, R
... plate-making roll, 5 ... bracket, 6 ... base end side bracket, 6a ... optical fiber insertion support part,
7: tip side bracket, 7a: optical fiber insertion support portion, 8: bush, 9: fastening piece, 10: wedge for angle adjustment,

Claims (1)

[Claims] 1. A laser beam emitted from each semiconductor laser is passed through a corresponding optical fiber, and an array of laser beams emitted from all the optical fibers to an optical lens system is arranged in a single line. A laser beam squeezed while maintaining a single-row array with an optical lens system, and irradiating the plate-making roll rotating at a constant speed, wherein the optical fiber is closer to the optical lens system. Are fixed to an optical fiber insertion support formed on the distal end side bracket, and the optical fiber insertion support is provided in parallel with a required number of diagonally arranged required sets, For a pair of obliquely arranged optical fiber insertion supports, the pitch P1 shifted in the surface length direction of the plate making roll is:
The pitch P2, which is 1/2 to about 3/5 of the diameter of the laser light incident on the optical lens system from the optical fiber, and is shifted in the circumferential direction of the plate making roll, maintains the strength of the bracket for fitting and fixing the optical fiber. To separate the dimensions as appropriate,
The pitch P3 shifted in the direction of the surface length of the plate making roll between the diagonal arrangement line of one set of optical fiber insertion support portions and the oblique arrangement of one set of adjacent optical fiber insertion support portions is the pitch P1 shifted in the surface length direction of the plate making roll. And a value obtained by multiplying the number of a set of optical fiber insertion support portions by a number of optical fiber insertion support portions.