JP2003326757A - Laser exposing unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent image compression due to relative delay of the conveyance speed of the photo sensitive material of the laser exposing unit with respect to the laser beam scanning speed derived from setting of the conveyance speed of a photo sensitive material of a laser exposing unit at the same speed as the conveyance speed of a photosensitive material of a developing processing unit for achieving miniaturization of a photography processing unit. <P>SOLUTION: Interposed exposure of image data of the next line on image data for one line derived from relative delay of the conveyance speed of a photosensitive material 1A with respect to the rotation rate of the polygon mirror 118 suppressed by randomly using the reflection surfaces of a polygon mirror 118. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser exposure apparatus that exposes a photosensitive material with a laser beam to form an image.

[0002]

2. Description of the Related Art In recent years, a photographic processing apparatus for forming an image on a photosensitive material using image data picked up by a digital camera or image data read by a scanner has been put into practical use. Such a photographic processing apparatus includes a magazine that stores a photosensitive material, a laser exposure device that exposes the photosensitive material pulled out from the magazine, a development processing device that performs development processing on the photosensitive material that has been exposed to the laser beam, and the like. It is composed of.

The developing device is provided with a transport mechanism for transporting the photosensitive material at a constant speed and a plurality of transport mechanisms arranged on the photosensitive material transport path.
Each is equipped with a container for storing a chemical such as a developing solution and a bleaching solution. The development process is performed by immersing the photosensitive material in a chemical to cause a chemical reaction. To cause a sufficient chemical reaction, the photosensitive material must be dipped in various chemicals for a predetermined time. When the transport speed of the photosensitive material in the developing device is increased, the transport path of the photosensitive material must be lengthened and the volume of each container must be increased in order to secure the time for immersing the photosensitive material in various chemicals. On the contrary, in order to shorten the conveying path of the photosensitive material and reduce the volume of each container to reduce the size of the photo processing apparatus,
In order to secure the time for immersing the photosensitive material in various chemicals, it is necessary to set the conveying speed of the photosensitive material on the developing processor side to a low speed.

The laser exposure apparatus is, for example, R (red), G
The intensity of the laser beam such as (green) and B (blue) is modulated by using the image data, the modulated laser beam is reflected by the reflecting surface of the polygon mirror rotating at a constant speed, and the reflected laser beam is made into a photosensitive material. Exposure is performed by scanning the top in a direction (main scanning direction) orthogonal to the carrying direction (sub scanning direction).

As the bearing type of the polygon mirror, there are bearing types such as a ball bearing bearing, an oil bearing and an air bearing. When rotating the polygon mirror at a low speed, a ball bearing bearing or an oil bearing type polygon mirror can be used, but a ball bearing bearing or an oil bearing type polygon mirror has low mechanical accuracy and poor durability. It is not suitable for use in machines that require high definition and high durability, such as photo processing devices. Therefore, in the photo processor,
Air bearing type polygon mirrors with high mechanical accuracy and excellent durability are widely used. However, since the operation of the air-bearing type polygon mirror is not stable unless a high speed and a constant rotation speed is applied, it is necessary to set the rotation speed of the polygon mirror to high speed in consideration of stability when designing the device.

As described above, in the photographic processing apparatus, it is preferable to use the air bearing type polygon mirror from the viewpoint of mechanical accuracy and durability. However, the conveyance speed of the photosensitive material of the laser exposure apparatus is set to that of the polygon mirror. When set to a high speed in order to synchronize with the rotation speed, at a position before the exposed photosensitive material is guided to the development processing device, the difference between the low speed and the conveyance speed of the photosensitive material on the development processing device side is absorbed. A mechanism, for example, a retracting mechanism must be provided, and the photo processing device cannot be downsized. The miniaturization and simplification of industrial products is always required, and the photo processing apparatus cannot be excluded from this requirement. In that sense, it is very significant to be able to absorb the conveyance speed of the photosensitive material in the development processing apparatus and the conveyance speed of the photosensitive material of the laser exposure apparatus without providing a special retracting mechanism.

[0007]

However, if the conveying path of the photosensitive material is shortened and the retracting mechanism is omitted in order to downsize the photographic processing apparatus, the conveying speed of the photosensitive material on the developing processing apparatus side becomes low. In addition, the transport speed of the photosensitive material on the laser exposure device side and the transport speed of the photosensitive material on the development processing device side must be the same. It becomes extremely slow with respect to the rotation speed of the mirror. If the photosensitive material is scanned and exposed with a laser beam in such a state,
From the end of the exposure of the image data of one line to the start of the exposure of the image data of the next line, the photosensitive material is not conveyed for one line (one line interval required for normal image formation) The image data is exposed by being overlapped with the image data of the next one line, and the image is consequently compressed in the transport direction.

Therefore, in order to avoid image compression,
The rotation speed of the polygon mirror and the conveyance speed of the photosensitive material on the laser exposure device side must be synchronized. As described above, when the air bearing type polygon mirror is used, it is necessary to set the conveying speed of the photosensitive material on the developing processing apparatus side to a low speed. Therefore, the conveying speed of the photosensitive material on the laser exposing apparatus side and the developing processing apparatus side are set. Since there is a difference between the speed of transporting the photosensitive material and the speed of transporting the photosensitive material, a mechanism for absorbing the speed difference must be provided again at a position before the photosensitive material is introduced into the developing processing device. The device becomes larger and more complicated.

The present invention has been made to solve the above problems, and in order to reduce the size of a photographic processing apparatus,
This occurs because the rotation speed of the polygon mirror is faster than the conveyance speed of the photosensitive material in the laser exposure device, as a result of setting the conveyance speed of the photosensitive material in the laser exposure device to the same speed as the conveyance speed of the photosensitive material in the development processing device. The purpose is to prevent image compression.

[0010]

The invention according to claim 1 is
A laser light source that outputs a laser beam of a predetermined wavelength, a transport mechanism that transports the photosensitive material at a first speed, and a second speed that rotates the laser beam and reflect the laser beam output from the laser light source on a reflecting surface. The polygon mirror for scanning the laser beam in the direction intersecting with the conveying direction of the photosensitive material, and the laser for preventing the image compression due to the second speed being higher than the first speed. The laser exposure apparatus is provided with an exposure adjustment unit that adjusts the exposure timing of the beam.

In this case, in order to downsize and simplify the photographic processing apparatus to which the laser exposure apparatus is applied, the photosensitive material conveyance speed in the laser exposure apparatus is made the same as the photosensitive material conveyance speed in the development processing apparatus. Even if the setting is made, the exposure timing of the laser beam is adjusted by the exposure adjusting means, so that the compression of the image due to the rotation speed of the polygon mirror being faster than the conveying speed of the photosensitive material can be prevented. Becomes

Further, it is preferable that the exposure adjusting means adjusts the time from the end of scanning one image data line of the laser beam to the start of scanning the next image data line.

In this case, the image data of one line is prevented by the exposure adjusting means so that the one image data line (one line of image data) and the next image data line (next one line of image data) are not overlapped and exposed. After the end of the scanning, the scanning of the image data of the next one line is started after waiting for the photosensitive material to be conveyed to the predetermined position, so that the image compression can be prevented.

Further, it is preferable that the exposure adjusting means is used by thinning the reflecting surface of the polygon mirror.

In this case, after the scanning of the image data of one line is completed by the exposure adjusting means, the scanning of the image data of the next one line waits for the reflecting surface of the polygon mirror to pass a predetermined number of surfaces. Then, the exposure of the image data of the next one line is started. That is, since the reflecting surface of the polygon mirror is thinned out and used, the time required for scanning one line becomes long, that is, the apparent scanning speed becomes slow, and the conveyance speed of the photosensitive material and the rotation speed of the polygon mirror are synchronized. This prevents the image from being compressed.

Further, it is preferable that the exposure adjusting means exposes a plurality of lines using the same image data when forming an image of one line.

In this case, an image for one line is formed on the photosensitive material by exposing the same image data for a plurality of lines. Therefore, the concentration distribution of the image of one line formed on the surface of the photosensitive material in the conveying direction of the photosensitive material becomes gentle, so that the reciprocity law failure (the amount of photochemical reaction is determined by the product of the intensity of the acting light and the time). There is a law of law, but do not obey this law of reciprocity law.) The problem is solved and the image quality can be improved.

Further, it is preferable that the exposure adjusting means weakens the light quantity of the laser beam.

In this case, the same image data is exposed by a plurality of lines to form an image of one line, and the light amount of the laser beam per scanning is weakened. The density is kept low, and the image quality is improved.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 shows a schematic configuration of a photographic processing apparatus using a laser exposure apparatus according to the first embodiment of the present invention. The laser exposure device is provided inside the housing 11B of the photographic processing device so as to face the exposure position 5X on the conveyor 5 that conveys the photosensitive material 1. The conveyor 5 has a plurality of sets of drive rollers 5A.
And a driven roller 5B and a guide rail 5C. On the upper surface 11A of the housing 11, a plurality of, for example, 2
Two magazines 20A and 20B are mounted.

Two sets of sensors 21A are provided to detect the types of photosensitive materials stored in the magazines 20A and 20B.
And 21B are provided on the magazines 20A and 20B, respectively, and on the upper surface 11A of the housing 11. Further, a densitometer 22 for measuring the density of the test print is provided on the upper surface 11A of the housing 11.

Housing 11, magazines 20A and 20
B is a dark box, and the tip 1B of the photosensitive material 1 is pulled out from the magazines 20A and 20B to the inside 11B of the housing 11. The photosensitive material 1 is the housing 1.
1 is cut into a predetermined size by a cutter 4 provided inside 1B. Hereinafter, the photosensitive material 1 cut into a predetermined size is referred to as a “photosensitive material piece 1A”. The photosensitive material piece 1A is conveyed from the exposure position 5X to the developing unit 2 by the conveyor 5 in the inside 11B of the housing 11.

The developing unit 2 includes a plurality of tanks 2A to 2A each containing a developing solution, a fixing solution, a bleaching solution and a stabilizing solution.
Have 2D. When the photosensitive material piece 1A exposed by the laser exposure device is conveyed through the developing unit, the latent image is developed and an image is formed on the photosensitive surface of the photosensitive material piece 1A.
The photosensitive material piece 1A is developed by causing a chemical reaction with a chemical such as a developer stored in the developing unit 2. In order to obtain a clear image, it is necessary to immerse the photosensitive material piece 1A in the chemicals in the developing unit 2 for a certain period of time. Conveyor 5
If the speed is set to a high speed, in order to secure the time for the chemical reaction between the photosensitive material piece 1A and the chemical, the conveying path of the conveyor 5 must be lengthened, and the volume of the developing unit 2 must be increased. The size of the photo processing device is increased because it is necessary. Therefore, in order to shorten the conveying path of the conveyor 5 and downsize the photographic processing apparatus, it is necessary to set the conveying speed of the photosensitive material piece 1A to a predetermined speed or less. Therefore, in the photographic processing apparatus of the first embodiment, the conveying speed of the photosensitive material piece 1A is set so as to be a speed suitable for downsizing the apparatus.

The developed photosensitive material piece 1A is dried by the drying unit 3 and discharged from the inside 11B of the housing 11. The developed photosensitive material piece 1A has a housing 11
Are stacked on the sorter 6 provided on the upper surface 11A of the.

The photo processing apparatus includes a control unit 12 provided in the housing 11, a monitor display 15 such as a CRT, a keyboard 16 and a mouse 17. From these, the operator can input commands and data, and can know information regarding the development of the photosensitive material 1. The monitor display 15, the keyboard 16 and the mouse 17 constitute an input / output unit 140. The input / output unit 140 is the housing 11 of the photo processing device.
It may be provided separately from, or may be provided integrally with the housing 11. In addition, in the vicinity of the exposure position 5X,
Paper sensor 15 for detecting the tip of the photosensitive material piece 1A
5 are provided.

Next, FIG. 2 shows a block configuration of the laser exposure apparatus in the first embodiment. The laser exposure apparatus has three laser light sources 104R and 104R that output laser beams of three primary colors of R (red), G (green) and B (blue), respectively.
G and 104B. The laser light source 104R includes a semiconductor laser that outputs a red (R) laser beam having a wavelength of 680 nm. The laser light source 104G has a wavelength of 1064
wavelength of 532 nm as the second harmonic of the YAG laser of nm
SHG laser that outputs a green (G) laser beam (sec
ond harmonic generation from laser) is included. Similarly, the laser light source 104B includes an SHG laser that outputs a blue (B) laser beam having a wavelength of 473 nm. Each of the laser light sources 104R, 104G and 104B includes a set of collimator lenses and the like (the green and blue laser light sources 104G and 104B are not shown).

Furthermore, three sets of acousto-optic modulators (Acousto
-Optical modulators such as optical modulators 106R and 106R
G and 106B, and the slit plates 108R, 108G and 108B correspond to the respective laser light sources 104R, 104G and 10.
It is arranged on the optical path in front of 4B. Further, in order to reflect the laser beams output from the respective laser light sources 104R, 104G and 104B toward the polygon mirror 118, mirrors 112R, 112G, 112B and 114 are provided.
And a lens 116 are provided on the optical path.

The mirror 112R is a total reflection mirror.
The laser beam is reflected to the mirror 112G side. Mirror 1
12G is a half mirror that transmits the R laser beam and reflects the G laser beam to the mirror 112B side. The mirror 112B is a half mirror that transmits the R laser beam and the G laser beam and reflects the B laser beam to the mirror 114 side. With such a configuration, the R, G, and B laser beams are superimposed (combined).

The polygon mirror 118 is rotated at a constant speed in the direction indicated by arrow A, for example, and reflects the laser beam in a predetermined range. The laser exposure apparatus of the first embodiment uses an air bearing type from the viewpoint of durability. As described above, in order to reduce the size of the photographic processing apparatus, the conveying speed of the photosensitive material piece 1A must be set to a predetermined speed or less (for example, 50 mm / s).
On the other hand, since the air bearing type polygon mirror has poor stability at low speed rotation, the rotation speed of the polygon mirror 118 cannot be set below a predetermined speed. for that reason,
In the photographic processing apparatus according to the first embodiment, the conveyance speed of the photosensitive material piece 1A is slower than the rotation speed of the polygon mirror 118. Specifically, the polygon mirror 1
Since the rotation speed of 18 is too high, the scanning of the laser beam and the conveyance of the photosensitive material piece 1A cannot be synchronized as they are.

An fθ lens 120 is provided in front of the polygon mirror 118.
The θ lens 120 deflects the laser beam in the main scanning direction indicated by arrow B. Since the photosensitive material piece 1A is conveyed by the conveyor 5 in the direction perpendicular to the paper surface of FIG. 2, the latent image corresponding to the image data used for modulating the laser beam is exposed by the photosensitive material piece 1A. The surface is exposed. A mirror 131 for reflecting the laser beam to the synchronous sensor 130 side is provided on the emission side of the fθ lens 120, in the immediate vicinity of the image exposure area and on the upstream side in the main scanning direction B.
Is provided. The synchronization sensor 130 is composed of, for example, a light receiving element, and outputs a synchronization signal S1 by receiving an R laser beam, for example.

In the laser exposure apparatus, the intensity of each laser beam is set to be substantially constant when they are output from the laser light sources 104R, 104G and 104B. The intensities of the laser beams output from the laser light sources 104R, 104G, and 104B are modulated by the light modulation elements 106R, 106G, and 106B according to the gradation levels of the R, G, and B components included in the image data. It

The laser exposure apparatus has a main controller 10 such as a CPU for controlling the overall operation of the laser exposure apparatus.
1 and RAM for temporarily storing various data
It further includes a (random access memory) 102, a ROM (read only memory) 103 storing a control program of the laser exposure apparatus, and the like. These are included in the control unit 12.

The conveyor drive unit (CD) 50 and the polygon mirror drive unit (PMD) 51 are connected to the main control unit 101 for controlling the conveyance of the photosensitive material piece 1A by the conveyor 5 and the rotation control of the polygon mirror 118, respectively. ing.

Three laser drive units (LD) 105R, 1
05G and 105B are the main controller 101 and the laser light source 1.
It is connected between 04R, 104G and 104B,
The intensity of the laser beam output from the laser light sources 104R, 104G and 104B is controlled to be kept constant.

Three light modulation element drive units (MD) 107
The R, 107G, and 107B are connected between the main control unit 101 and the light modulation elements 106R, 106G, and 106B, and light R, G, and B are lighted according to the gradation degree of each component of R, G, and B included in the image data. Modulation elements 106R, 106G and 1
The intensity of the laser beam passing through 06B is controlled to be modulated.

LUT (look-up table) 1040
Are two types of lookup tables 1041 and 1042
With. The lookup table 1041 is a lookup table used in the first embodiment, and the lookup table 1042 is a lookup table used in a second embodiment described later. The look-up tables 1041 and 1042 are respectively a plurality of look-up tables 1 corresponding to respective combinations of types of photosensitive materials and types of developing solutions that can be used in this photographic processing apparatus.
041, 1041, 1041, ... And lookup tables 1042, 1042, 1042.

Each lookup table 1041 and 10
Reference numeral 42 has a storage capacity sufficient to store, for example, 12-bit data, and stores 4096 gradation levels of 0 to 4095 for each of the R, G, and B color components. Each lookup table 1041 and 10
The optical modulation data stored in 42 is the optical modulation element 10
Lookup tables 1041 and 104 used to modulate the laser beam by 6R, 106G, and 106B.
2 is stored in the address of the same value as the gradation level, for example.

The image processing section 150 includes the input / output unit 14
The image data input via 0 is subjected to predetermined image processing and the input / output of image data is controlled. Image memory 1
Reference numeral 51 temporarily stores the input image data for each of the R, G, and B color components. The clock control unit 152
Upon receiving the synchronization signal S1 output from the synchronization sensor 130, the image processing unit 150 reads out image data from the image memory 151 and the optical modulator driving unit 107R, 1R.
It controls the timing of outputting image data to 07G and 107B.

Next, FIG. 3 shows a block diagram of a clock controller 152 of the laser exposure apparatus according to the first embodiment and various circuits connected to the clock controller 152.

As shown in FIG. 3, the image processing unit 150 is
The image processing units 150R, 150G and 150B are provided.
The image processing units 150R, 150G, and 150B respectively perform predetermined shading correction, color balance correction, and the like on the image data DR, DG, and DB of the R, G, and B components of the image data read by a scanner or the like. Image processing of. Further, the image processing units 150R, 150G, and 150B are each configured to perform image processing on the image data D.
Light modulation data MDR, MD stored in the lookup table 1041 according to the gradation levels of R, DG, and DB.
G and MDB reading, image memory 151R, 151G
And 151B. Image processing units 150R, 150
G and 150G output the light modulation data MDR, MDG, and MDB pixel by pixel to the image memories 151R, 151G, and 151B in synchronization with the clock signal CL output from the clock generation unit 1523, respectively.

The image memory 151 has an image processing section 150.
Image memories 151R, 151G and 151B, which are respectively connected to R, 150G and 150B by a 12-bit parallel line, and store optical modulation data MDR, MDG and MDB. The image memories 151R, 151G, and 151B are synchronized with the clock signal CL output from the clock generation unit 1523 (described later), with respect to the buffer memories 153R, 153G, and 153B.
The light modulation data MDR, MDG, and MDB are output pixel by pixel.

The buffer memory 153 is the image memory 15
Buffer memories 153R and 153R connected to 1R, 151G, and 151B by 12-bit parallel lines, respectively.
53G and 153B. Buffer memory 153
Each of R, 153G, and 153B is composed of a shift register capable of parallel transfer of 12-bit data, and has a capacity capable of storing one line of the light modulation data MDR, MDG, and MDB. The image memories 151R, 151G and 151B are synchronized with the clock signal CL from the clock generator 1523,
The optical modulation data MDR, MDG, and MDB are read pixel by pixel from the image memories 151R, 151G, and 151B, and the read optical modulation data MDR, MDG, and MDB are read.
To the register on the right. Also, the buffer memory 1
53R, 153G, and 153B synchronize with the clock signal CL output from the clock generator 1523 when the enable signal ES output from the exposure counter 1522 (described later) rises, and the D / A converter 154R, The optical modulation data MDR, MDG, and MDB are output to the 154G and 154B pixel by pixel.

The D / A converter 154 is connected to the buffer memories 153R, 153G and 153B by a 12-bit parallel line, respectively.
4R (D / A), 154G (D / A) and 154B (D
/ A). D / A converter 154R, 154G
And 154B receive the optical modulation data MDR, MDG, and MDB for one pixel output from the buffer memories 153R, 153G, and 153B in synchronization with the clock signal CL output from the clock generation unit 1523, respectively. The light modulation data MDR, MDG, and MDB for one pixel are converted into analog signals ASR, ASG, and ASB, and the light modulation element driving units 107R, 107G, and 107 are used.
Output to B.

The clock controller 152 includes a synchronization signal counter 1521, an exposure counter 1522, and a clock generator 1523.

The synchronization signal counter 1521 outputs an exposure start signal S2 to the exposure counter 1522 when the synchronization signal S1 output from the synchronization sensor 130 is counted for four pulses. When the synchronization sensor 130 receives the R laser beam, it outputs the synchronization signal S1.
Is output when the R laser beam starts to be reflected by one reflecting surface of the polygon mirror 118, the synchronizing signal counter 1521 counts the synchronizing signal S1 for four pulses, and then the And start the exposure,
The reflecting surface of the polygon mirror 118 is drawn for three surfaces and used. Therefore, a fixed time interval elapses from the end of the exposure of the image data for one line, and the photosensitive material piece 1A
Is conveyed to an appropriate position, the exposure of the next one line is started, and the image data of the next one line does not overlap the image data of the one line, and the image is compressed in the conveying direction. A proper image can be obtained without causing overlapping of colors and colors.

The exposure counter 1522 has an exposure start signal S.
When 2 is received, counting of the clock signal CL output from the clock generation unit 1523 is started. Then, the exposure counter 1522 raises the enable signal ES to be output to the buffer memories 153R, 153G and 153B when the clock signal CL is counted by a predetermined pulse. Further, when the exposure counter 1522 raises the enable signal ES and then counts the clock signal CL by a predetermined pulse, the exposure counter 1522 lowers the enable signal ES in order to end the exposure of the image data for one line.

The clock generator 1523 is provided for the photosensitive material piece 1A.
A clock signal (dot clock signal) CL for determining the timing of exposing the image data for one pixel is generated on the upper side, and the generated clock signal CL is used for the image memory 151.
R, 151G and 151B, buffer memory 153R,
153G and 153B, D / A converter 154R, 1
The signals are output to 54G and 154B and the like to synchronize the operations of various circuits constituting the laser exposure apparatus.

FIG. 4 is a diagram for explaining the principle of obtaining an appropriate image in the photographic processing apparatus of the first embodiment. FIG. 4A is an exposure when the reflecting surface of the polygon mirror 118 is thinned out and not used. The exposed photosensitive material piece 1A is shown, and (b) shows the exposed photosensitive material piece 1A when the reflective surface of the polygon mirror 118 is thinned out and used.

As shown in FIG. 4A, when the reflecting surface of the polygon mirror 118 is not thinned and used, assuming that one line of image data PG1 is exposed using the reflecting surface P1 of the polygon mirror, The image data PG2 for one line is exposed using the reflecting surface P2. As a result, since the time interval from the end of the exposure of the image data PG1 for one line to the start of the exposure of the image data PG2 for the next one line is short, the photosensitive material piece 1A is not sufficiently conveyed in the sub-scanning direction. Exposure of the image data PG2 is started. Therefore, the image data PG1 exposed on the photosensitive material piece 1A overlaps with the image data PG2 exposed on the photosensitive material piece 1A by the reflecting surface P2, and the overlapping line DL is formed and the image is compressed.

On the other hand, in the laser exposure apparatus according to the first embodiment, if the image data PG1 is exposed on the photosensitive material piece 1A by the reflecting surface P1 of the polygon mirror as shown in FIG. The image data PG2 of the line is exposed using the reflecting surface P5, and the image data of the next one line is exposed using the reflecting surface P3, and so on ... Since it is used (thinned), the image data PG1 and the image data PG2 do not overlap and are not exposed, and image compression is avoided.

Next, this operation will be described in detail with reference to FIG. First, when the exposure of one line of image data PG1 is completed using the reflecting surface P1, the R laser beam is reflected by the reflecting surface P2 and detected by the synchronization sensor 130 immediately after the start of reflection. Then, the synchronization sensor 130
The synchronizing signal S1 is output from the synchronizing signal counter 1521 to the synchronizing signal counter 1521 and the synchronizing signal counter 1521 is counted up. In this case, the R laser beam scans the photosensitive material piece 1A by the reflecting surface P2 by the rotational movement of the polygon mirror 118, but the R laser beam is superimposed with image data having a gradation of 0. Since the intensity of the laser beam is set to the weakest intensity, the photosensitive material piece 1A is not exposed. Further, the G and B laser beams are also scanned on the photosensitive material knit 1A in the same manner as the R laser beam.
A is not exposed.

Next, when the reflection of the R laser beam by the reflecting surface P3 is started, the synchronization sensor 130 outputs the synchronization signal S1 to the synchronization signal counter 1521, and the synchronization signal counter 1521 is counted up. In this way, when the synchronization signal counter 1521 counts the synchronization signal S1 for four pulses, it outputs the exposure start signal S2 to the exposure counter 1522. Upon receiving the exposure start signal S2, the exposure counter 1522 receives the buffer memory 153R,
The enable signal ES output to 153G and 153B is raised, and counting of the clock signal CL output from the clock generation unit 1523 is started.

When the enable signal ES is raised,
The buffer memories 153R, 153G and 153B respectively store the optical modulation data MDR for one line stored therein,
D / A converter 154 for each pixel of MDG and MDB
Output to R, 154G and 154B. The optical modulation data MDR, MDG, and MDB output from the buffer memories 153R, 153G, and 153B are respectively D / A.
The analog signals ASR, ASG, and ASB are converted by the converters 154R, 154G, and 154B and output to the light modulation element driving units 107R, 107G, and 107B. The R, G, and B laser beams output from the laser light sources 104R, 104G, and 104B are modulated by the optical modulators 106R, 106G, and 106B, respectively, according to the amplitudes of the analog signals ASR, ASG, and ASB (image data is Then, exposure is started on the photosensitive material piece 1A. As a result, the image data PG2 is exposed using the reflecting surface P5. Then, when the exposure of the image data PG2 ends, the exposure counter 1522 lowers the enable signal ES and stops the exposure.

Next, when the synchronization signal counter 1521 counts the synchronization signal S1 for four pulses, the synchronization signal counter 1521 outputs the exposure start signal S2 to the exposure counter 1522.
To the enable signal E.
S is started, and the image data PG3 is generated by the reflection surface P3.
Exposure is started.

As described above, according to the laser exposure apparatus of the first embodiment, since the reflecting surface of the polygon mirror is thinned out and used, as shown in FIG.
Since 1 and the image data PG2 do not overlap and are not exposed, a proper image can be obtained.

In the first embodiment, the synchronization signal counter 1521 outputs the exposure start signal S2 when the synchronization signal S1 is counted by 4 pulses, but the invention is not limited to this. The conveyance speed of the photosensitive material piece 1A is not limited to this. The counter value counted by the synchronization signal counter 1521 may be appropriately changed based on the relationship between the rotation speed of the polygon mirror and the rotation speed of the polygon mirror. In this case, the reflecting surface of the polygon mirror 118 is thinned and used according to the counter value of the synchronization signal counter 1521.

(Second Embodiment) Next, a second embodiment of the laser exposure apparatus according to the present invention will be described. FIG. 5 shows a clock control unit 252 of the laser exposure apparatus according to the second embodiment and a buffer memory 253 connected to the clock control unit 252.
It is a block diagram showing a configuration such as. As shown in FIG. 5, the laser exposure apparatus according to the second embodiment is different from the laser exposure apparatus of the first embodiment in the configurations of the buffer memory 253 and the clock control unit 252.

The buffer memory 253 is the image memory 15
A buffer memory 253 connected to 1R, 151G and 151B by a 12-bit parallel line PL.
R, 253G and 253B. Buffer memory 2
Since 53R, 253G, and 253B have the same configuration, the configuration of the buffer memory 253R will be described.

The buffer memory 253R includes shift registers 2531, 2532, 2533, 2534 and a multiplexer 2535. Each of the twelve signal lines forming the parallel line PL is branched into four at the branch point BR, and the four branched signal lines are connected to the shift registers 2531 to 2534, respectively. The data output side of each of the shift registers 2531 to 2534 is a multiplexer 25 using a 12-bit parallel line.
It is connected to 35. The data output side of the multiplexer 2535 has a 12-bit parallel line for D / A.
It is connected to the converter 154R.

The shift registers 2531 to 2534 are each capable of parallel transfer of 12-bit data,
Clock signal C output from the clock generator 2523
In synchronization with L, the light modulation data MDR stored in the image memory 151R is sequentially read in pixel units from the leading pixel. In addition, the shift registers 2531 to 2534 are
Each has a capacity capable of storing the optical modulation data MDR for one line. The shift registers 2531 to 2534 are
The light modulation data MDR of one pixel is output to the D / A converter 154R in synchronization with the clock signal CL.
In addition, the shift registers 2531 to 2534 are respectively
When the enable signal ES is raised by the exposure counter 2522, the light modulation data MDR can be output.

The multiplexer 2535 receives the control signal CS output from the clock control unit 252 in synchronization with the clock signal CL at the control terminal 2535T and shifts the shift registers 2531 to 2534 to 2531, 2532, and 232.
533, 2534, 2531, ...

The clock controller 252 uses the exposure counter 2
522 and a clock generator 2523. When the exposure counter 2522 receives the synchronization signal S1 output from the synchronization sensor 130, the exposure counter 2522 starts counting the clock signal CL output from the clock generator 2523, and when the clock signal CL is counted for a predetermined pulse, the enable signal ES is raised. increase.

Image processing units 150R, 150G and 150
B is image data DR, DG, and DB that have undergone image processing.
Of the look-up table 1042 according to the gradation.
Light modulation data MDR, MDG and MD stored in
B is read, and the read optical modulation data MDR and MDG
And MDB to the image memories 151R, 151G and 15
Output to 1B. In the second embodiment, one line of image data is exposed by exposing four lines of the same image data on the photosensitive material piece 1A. Therefore, the light modulation data stored in the lookup table 1042 is set to a value of 1/4 of the light modulation data stored in the lookup table 1041. Therefore, the density of the image data formed on the photosensitive material piece 1A by one scanning of the laser beam is 1/4 that of the case where the exposure is performed using the lookup table 1041.

Next, the operation of the laser exposure apparatus according to the second embodiment will be described. First, the optical modulation data MDR stored in the image memory 151R is synchronized with the clock signal CL, and the shift registers 2531 to 25 are pixel by pixel.
Data is written in each of 34 in parallel from the top pixel in order. Therefore, the shift registers 2531 to 2534
Will store the same light modulation data MDR. Next, when the enable signal ES is raised from the exposure counter 1522, the multiplexer 2535
Connects the shift register 2531 based on the control signal CS. Then, in synchronism with the clock signal CL, the optical modulation data MDR of one pixel from the shift register 2531 is D /
It is output to the A converter 154R. Then, when the next clock signal CL is generated, the multiplexer 2535
Is connected to the shift register 2532 based on the control signal CS, and the shift register 2532 outputs the light modulation data MDR of one pixel to the D / A converter 154R. In this way, the multiplexer 2535 sequentially switches the shift registers 2531 to 2534 in synchronization with the clock signal CL, so that the D / A converter 154R receives the same light modulation data four times. The buffer memories 253G and 253B are also the buffer memories 2
Similarly to 53R, the D / A converter 1 outputs the optical modulation data MDR in synchronization with the clock signal CL.
54G and 154B will each receive the same light modulation data four times. Therefore, the same image data is exposed four times on the photosensitive material piece 1A.

Next, image data exposed on the photosensitive material piece 1A by the laser exposure apparatus according to the second embodiment will be described with reference to FIG. FIG. 6 shows one line of image data PG exposed on the photosensitive material piece 1A. This image data PG is image data PG1, PG2, PG3.
And PG4 are overlapped and exposed.
As described above, the conveyance speed of the photosensitive material piece 1A of the laser exposure device is slower than the rotation speed of the polygon mirror 118. Therefore, when the image data of one line is reflected by one reflecting surface of the polygon mirror 118 and then the image data of the next one line is exposed by the adjacent reflecting surface, the exposed image data will overlap each other. Therefore, in the laser exposure apparatus of the second embodiment, when exposing one line of image data on the photosensitive material strip 1A, the same image data is exposed four times to form one image data. ing. For example, if the image data PG1 is exposed using the reflecting surface P1, the image data PG2 to PG3 that are the same image data as the image data PG1 are exposed using the reflecting surfaces P2 to P3, respectively. Then, as shown in FIG. 6, the density distribution of one line becomes the image data PG1 to
Due to the degree of overlap of PG2, the density is darkest in the vicinity of the center line CP and becomes lighter toward the end line EP, so that the density distribution of image data for one line becomes gentle. Therefore, the problem of reciprocity law failure is solved and a clear image can be obtained. Further, the laser exposure apparatus of the second embodiment is
Exposure of the image data PG1 to PG4 is performed because the look-up table 1042 in which the value of the light modulation data is set to 1/4 is used in consideration of exposing the image data of one line in four times. Since the respective densities are ¼ of the normal exposure densities, it is possible to prevent the densities from becoming too high near the center line CP, and a clearer image can be obtained.

In the second embodiment, one line of image data is formed by exposing the same image data four times, but the present invention is not limited to this, and three times or less, or
It may be set to 5 times or more. That is, the number of times the same image data is exposed may be set based on the balance between the conveyance speed of the photosensitive material piece 1A and the rotation speed of the polygon mirror. Further, the look-up table may be set according to the number of times the same image data is exposed.

[0067]

As described above, according to the present invention,
Since the exposure adjusting means is provided, in order to reduce the size of the photographic processing apparatus, as a result of setting the conveying speed of the photosensitive material of the laser exposure apparatus to the same conveying speed of the photosensitive material of the developing processing apparatus,
It is possible to prevent the image from being compressed due to the rotation speed of the polygon mirror becoming higher than the conveying speed of the photosensitive material in the laser exposure apparatus.

[Brief description of drawings]

FIG. 1 is a block diagram showing a photographic processing apparatus to which a laser exposure apparatus according to the present invention is applied.

FIG. 2 is a block diagram showing a laser exposure apparatus according to the present invention.

FIG. 3 is a block diagram showing a clock control unit and a circuit connected to the clock control unit of the laser exposure apparatus according to the embodiment of the present invention.

FIG. 4 is a view for explaining the principle of obtaining an appropriate image in the photographic processing device of the first embodiment (a).
6B shows the exposed photosensitive material pieces when the reflecting surface of the polygon mirror is not used by thinning it, and FIG. 9B shows the exposed photosensitive material pieces when the reflecting surface of the polygon mirror 118 is used by thinning it. There is.

FIG. 5 is a block diagram showing a configuration of a clock control unit and a circuit connected to the clock control unit according to a second embodiment of the present invention.

FIG. 6 is a diagram showing image data exposed on a photosensitive material piece by the laser exposure apparatus according to the second embodiment of the present invention.

[Explanation of symbols]

1: Photosensitive material 1A: Photosensitive material piece 101: Main control unit 102: RAM 103: ROM 104R, 104G, 104B: Laser light sources 105R, 105G, 105B: Laser driving units 106R, 106G, 106B: Light modulation elements 107R, 107G, 107B: Light modulator driving units 108R, 108G, 108B: Slit plates 112R, 112G, 112B: Mirrors 114, 131: Mirrors 116, 120: Lens 118: Polygon mirror 130: Synchronous sensor 140: Input / output units 150, 150R, 150G , 150B: image processing units 151, 151R, 151G, 151B: image memory 152: clock control units 153, 153R, 153G, 153B: buffer memories 154, 154R, 154G, 154B: D / A converter 155: paper sensor 1 40, 1041, 1042: Look-up table 1521: Sync signal counters 1522, 2522: Exposure counters 1523, 2523: Clock generators 253, 253R, 253G, 253B: Buffer memories 2531, 2532, 2533, 2534: Shift register 2535: Multiplexer 2535T: Control terminal

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Jun Hirooka             No. 1 at 579 Umehara, Wakayama City, Wakayama Prefecture             Inside Ritsu Koki Co., Ltd. F term (reference) 2C362 BA04 BB23 BB37 CB71 CB78                 2H045 CA98 DA41                 5C051 AA02 CA07 DA02 DB02 DB22                       DB24 DB31 DE02 DE30 EA01                       FA04                 5C072 AA03 BA17 HA02 HA06 HA09                       HA13 HB04 HB11 QA14 VA03                       XA05

Claims (5)

[Claims] 1. A laser light source for outputting a laser beam of a predetermined wavelength, a transport mechanism for transporting a photosensitive material at a first speed, and a second speed for rotation to reflect the laser beam output from the laser light source. The polygon mirror for scanning the laser beam in the direction intersecting the conveying direction of the photosensitive material by reflecting on the surface, and the image compression due to the second speed being higher than the first speed. A laser exposure apparatus comprising: an exposure adjustment unit that adjusts an exposure timing of a laser beam to prevent the exposure. 2. The exposure adjusting means is one of a laser beam.
2. The laser exposure apparatus according to claim 1, wherein the time from the end of the scanning of the image data line to the start of the scanning of the image of the next image data line is adjusted. 3. The laser exposure apparatus according to claim 2, wherein the exposure adjusting means thins and uses a reflecting surface of a polygon mirror. 4. The laser exposure apparatus according to claim 1, wherein the exposure adjustment means performs exposure for a plurality of lines using the same image data when forming an image of one line. 5. The laser exposure apparatus according to claim 4, wherein the exposure adjustment unit weakens the light quantity of the laser beam.