JP2001249411A - Exposure device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain images having high image quality by preventing color registration while maintaining high throughput capacity. SOLUTION: A prism 36 is arranged in the exposure device by which photographic paper 6 is line exposed with light of three colors R, G and B successively emitted from a light source. The refractive index of the prism 36 varies with each of the three colors R, G and B and is so adjusted as to compensate the exposure misregistration by the relative movement with respect to a halogen lamp 23 side of the photographic paper 6. The light of R, G and B for one line therefore arrives at the same small region 61.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus for performing exposure processing on a photosensitive material such as photographic paper, and more particularly, to an exposure apparatus capable of eliminating color registration.

[0002]

2. Description of the Related Art A photographic processing apparatus capable of automatically performing processing such as exposure, development, and bleaching on a photosensitive material such as photographic paper is known. When exposing photographic paper with such a photographic processing apparatus, direct (analog) exposure of exposing a photosensitive material with light transmitted through a photographic film is widely performed.

On the other hand, in recent years, digital exposure for exposing a photosensitive material with light controlled based on a digital image signal obtained by imaging a film has been put to practical use. By using the digital exposure method, various image processing such as color correction and density correction can be performed freely, rapid reprinting processing is possible, and higher color and density reproducibility and resolution are achieved. It is possible to obtain a print with good image quality.

[0004]

As one of digital exposure apparatuses for photosensitive materials, for example, R (red), G (green), B
A light source that sequentially emits light of three colors (blue) and a light source that extends in a direction substantially perpendicular to the direction in which the photosensitive material is conveyed and transmits (for example, a liquid crystal shutter) or reflects (for example, a digital Mirror device (DM
D)) There is a line exposure apparatus using a print head. When a color image is exposed by such a line exposure apparatus, the operation of exposing the photographic paper with light of three colors using image data for one line is performed by moving the photographic paper with respect to the light source in the extending direction of the print head. This is performed for all the lines constituting one image while relatively moving in the direction perpendicular to the direction.

In the above-described exposure apparatus, it is preferable to continuously move the photographic paper with respect to the light source from the viewpoint of improving the processing performance per unit time as much as possible.
However, the above-described exposure apparatus employs a method in which a light source sequentially emits light of three colors with a time shift, and when the photographic paper is continuously moved with respect to the light source, three light rays related to an image for one line are obtained. A color shift (so-called color registration) occurs in which the exposure position of the color light on the photographic paper is shifted for each color. Therefore, for example, it is impossible to completely overlap the exposure ranges of the three colors of RGB to produce black, and the sharpness and the maximum density (Dmax) are deteriorated, and the image becomes uneven. There is a problem that the image quality of the obtained image is deteriorated.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an exposure apparatus which has a high processing capability and can obtain a high quality image by preventing color registration.

[0007]

In order to achieve the above object, an exposure apparatus according to the present invention is an exposure apparatus for sequentially exposing a photosensitive material, which continuously moves relative to a light source section, with light of a plurality of colors. To reduce the exposure position shift of the light of the plurality of colors on the photosensitive material due to the relative movement,
An optical element having a different refractive index for each of the plurality of colors of light is provided.

According to a second aspect of the present invention, there is provided an exposure apparatus, wherein a light source unit for sequentially emitting light of a plurality of colors and the light of the plurality of colors from the light source unit are selectively provided for each line constituting two-dimensional image data. Light control means for sequentially reflecting or transmitting light; position changing means for continuously moving the photosensitive material relative to the light source unit; and a shift in the exposure position of the light of the plurality of colors on the photosensitive material due to the relative movement. Refraction means having a different refractive index for each of the plurality of colors of light so as to be smaller.

According to the first and second aspects, the refractive index differs for each of the plurality of colors of light so that the exposure position shift of the plurality of colors of light on the photosensitive material due to the relative movement between the photosensitive material and the light source unit is reduced. Or a refracting means for refracting light with a different refractive index. That is, the optical element or the refracting means used in the present invention corresponds to the relative movement between the photosensitive material and the light source section, and the exposure position of a plurality of colors of light related to the same pixel of the light control means by one line of exposure. It has chromatic aberration such that the displacement is small. Thus, even if the photosensitive material is continuously moved relative to the light source unit, the color registration can be reduced as compared with the conventional case where such an optical element does not exist. Therefore, it is possible to obtain a high-quality image which does not cause deterioration of sharpness while maintaining relatively high processing performance. The refracting means may be composed of only one optical element, or may be composed of two or more optical elements.

In an exposure apparatus according to a third aspect, the refracting means includes:
Each of the plurality of colors of light has a different refractive index so as to eliminate the exposure position shift of the plurality of colors of light on the photosensitive material due to the relative movement. According to the third aspect, color registration is eliminated, and a higher quality image can be obtained.

According to a fourth aspect of the present invention, in the exposure apparatus, the refracting means includes:
It has a function of forming an image of light on a photosensitive material. According to the fourth aspect, since it is not necessary to form the refraction means as a member separate from the exposure lens for imaging, the size of the apparatus can be reduced.

In an exposure apparatus according to a fifth aspect, the refracting means includes:
It is characterized by including one of a lens and a prism having a different refractive index for each of the plurality of colors of light. According to the fifth aspect, since the refraction means is a lens or a prism, the refraction means can be easily configured.

According to a sixth aspect of the present invention, one dot formed on the photosensitive material corresponds to a plurality of pixels of the light control means. According to claim 6,
By forming one dot of the photosensitive material using a plurality of pixels of the light control means, the time required for exposure can be shortened compared to the case of forming one dot of the photosensitive material using one pixel of the light control means. As a result, the processing capacity can be further improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a schematic configuration of a photographic processing apparatus incorporating an exposure apparatus according to a first embodiment of the present invention. The photographic processing apparatus 1 shown in FIG. 1 includes a printer unit (exposure device) 2, a processor unit 3, and a finishing processing unit 4. The printing paper 6 cut to a predetermined length by cutters 13 and 14 described later is conveyed from the printer unit 2 to the finishing unit 4 via the processor unit 3 along a path shown by a dashed line in FIG. You. In the printer unit 2,
Mainly, exposure printing processing of an image based on digital data is performed on photographic paper 6 which is a photosensitive material. In the processor section 3, the exposed photographic paper 6 sequentially passes through a liquid tank (not shown) in which different liquids are stored, so that processing such as development, bleach-fixing, and stabilization is performed on the photographic paper 6. You. In the finishing section 4, the photographic paper 6 processed by the processor section 3 is subjected to a drying process, and the photographic paper 6 dried and discharged from the discharge port 5 is sorted for each order.

The printer unit 2 includes cutters 13 and 14 for cutting the photographic paper 6 having a predetermined width drawn out from the paper magazines 11 and 12 that store the wound long photographic paper 6 into predetermined lengths. A chucker 15 for transporting the photographic paper 6 cut to a predetermined length to a stage preceding the exposure position, an exposure unit 16 for performing an exposure process on the photographic paper 6, and a photosensitive emulsion layer of the photographic paper 6 on which no photosensitive emulsion layer is formed A printing unit 17 for printing desired characters on the front side (back side), a roller pair 18a for pulling out the photographic paper 6 from the paper magazines 11 and 12 and transporting the photographic paper 6 to the chucker 15, and a photographic paper 6 from the chucker 15 It has a pair of rollers (position changing means) 18b for receiving and continuously transporting it to the processor unit 3.

The exposure unit 16 includes a halogen lamp 23 as a light source, and a color wheel 24 formed as a rotatable single disk made up of fan-shaped three-color RGB filters as shown in FIG. The print head 25 is configured to guide light emitted from the halogen lamp 23 and passing through the color foil 24 via an optical fiber (not shown). The halogen lamp 23 and the color wheel 24 constitute a light source unit that sequentially emits light of three colors RGB as the color wheel 24 rotates.

The print head 25 is provided with an optical shutter section (light control means) 34 having a PLZT crystal, which is an electro-optical element having an electro-optical effect, and on the photographic paper 6 side of the optical shutter section 34. For example, an exposure lens 35 for forming an image of light on the photographic paper 6, which is a SELFOC lens array capable of forming an equal-magnification normal image, and is disposed closer to the photographic paper 6 than the exposure lens 35. , RGB
Prism (optical element, refraction means) 36 (see FIG. 3) having a different refractive index for each color of light.

The PLZT crystal constituting the optical shutter section 34 is a transparent ferroelectric ceramic material obtained by adding lanthanum to lead zirconate titanate, and has a property that the birefringence changes according to an applied voltage. In addition, it functions as an optical shutter that can select a state where light is transmitted or a state where light is blocked by controlling a voltage applied to a drive electrode 54 (see FIG. 2) provided for each pixel.

The optical shutter 34, the exposure lens 35, and the prism 36 extend one-dimensionally in a direction perpendicular to the direction in which the photographic paper 6 is transported (ie, in a direction perpendicular to the plane of FIG. 1). Therefore, by controlling the timing of transporting the printing paper 6 by the pair of rollers 18b and the timing of opening and closing the optical shutter unit 34 of the print head 25, the photosensitive emulsion surface of the printing paper 6 is line-exposed to print a latent image of a desired image. It can be formed on paper 6.

The prism 36 has a different refractive index for each color of RGB light, and as will be described in detail later, for example, hardly refracts blue light and refracts green light by a slight angle. The red light may be refracted at a larger angle than the green light. And the prism 36
Are arranged such that the direction of refraction of these lights is the same as the moving direction of the printing paper 6 with respect to the halogen lamp 23. Therefore, by using the prism 36,
The displacement of the exposure positions of the three colors of light on the printing paper 6 can be reduced, and preferably, the displacement of the exposure positions can be eliminated. Note that a lens can be used instead of the prism 36.

The chucker 15 has substantially the same width as the print head 25 and extends in the same direction as the print head 25, and also has a grip (see FIG. 1) for stably holding or holding the printing paper 6 cut by the cutters 13, 14. (Not shown). In addition, the chucker 15 has two paper magazines 1.
The upper end position 31 which is the intersection of the transport path of the photographic paper 6 from the printing papers 1 and 12 and the roller pair 1 in the preceding stage of the print head 25
It is possible to move up and down between the lower end position 32 immediately before 8b. That is, the chucker 15 receives the photographic paper 6 cut to a predetermined length at the upper end position 31 and holds the photographic paper 6 by closing the grip, thereby holding the lower end position 32.
The grip is released and the roller pair 18b at the subsequent stage is released.
Can be provided with photographic paper 6.

The chucker 15 can be moved not only in the vertical direction but also in the direction perpendicular to the direction in which the photographic paper 6 is conveyed (the direction perpendicular to the plane of FIG. 1). Therefore, Chukka 1
5 repeats the operation of sandwiching one photographic paper 6 having a width smaller than that of the print head 25 and moving the photographic paper 6 in the width direction, thereby simultaneously extending the plurality of photographic papers 6 and extending the print head 25. These can be conveyed downward while being held in parallel in the direction.

The printing unit 17 has a known printing head (not shown) such as a thermal head, and a desired character or symbol is formed on a surface (back surface) of the photographic paper 6 on which the photosensitive emulsion layer is not formed. It is configured to be printable.

In this embodiment, the printer unit 2 includes a control unit 19 for controlling the entire operation of the photographic processing apparatus 1 and a correction value for the number of prints, color and density at the time of printing, etc. (Input means) 20 for inputting the information, and a monitor 2 for displaying various information related to the photo processing apparatus 1 to notify the operator and to prompt the operator to input from the keyboard 20 as necessary.
1 and a data capturing unit 22 for capturing image data to be exposed on the photographic paper 6.

The data take-in section 22 may be of any type as long as it can take in image data to be exposed recorded on each frame of the film and supply it to the control unit 19. For example, it may be an image reading device such as a scanner equipped with a CCD image sensor capable of reading an image recorded on each frame of a film, or may be recorded on a data recording medium such as a floppy (registered trademark) disk or MO. It may be a data reading device capable of reading the read image data, or may be a connection interface with an external image reading device or a data reading device.

FIG. 2 is a block diagram of a control system of the photographic processing apparatus 1 shown in FIG. As shown in FIG. 2, the control unit 19 includes a CPU 41 and a ROM 4 connected to each other.
2, a RAM 43, and an input / output interface 44. The input / output interface 44 includes a keyboard 20, a monitor 21, a driver 45 for driving the halogen lamp 23, a driver 46 for driving a motor 51 for rotating the color wheel 24, and a light shutter unit 34 having the same number of pixels. A driver 47 for driving the driving electrodes 54 provided, a driver 48 for controlling a motor 52 for driving the chucker 15 up, down, left and right; a driver 49 for controlling a motor 53 for driving the roller pair 18b; Is connected. In FIG. 3,
Illustration of control elements that are less relevant to the present invention is omitted.

The CPU (control means) 41 executes various calculations to generate signals for controlling the operation of each section of the photographic processing apparatus 1, and sends an operation command to each section of the photographic processing apparatus 1 according to the calculation result. Output. The signal generated by the CPU 41 is supplied to drivers 45 to 49 connected thereto via the input / output interface 44. ROM
The (storage means) 42 stores a program for an operation performed by the CPU 41 and data necessary for the program. RAM
The (storage means) 43 temporarily stores data provided from the keyboard 20, the data fetching unit 22, and the like, results of calculations by the CPU 41, and the like. In the RAM 43,
A line buffer is formed for temporarily storing one line of image data of each color of RGB of image data of a frame to be exposed and other editing information output as necessary.

In the photographic processing apparatus 1 configured as described above, when exposing the photographic paper 6, the roller pair 18b and the like are driven by the control of the CPU 41 to continuously direct the photographic paper 6 toward the processor unit 3. Each of the driving electrodes 54 is driven based on the image data obtained from the data capturing unit 22 while the color wheel 24 is rotated at a constant speed while being conveyed without stopping, and only a desired position on the printing paper 6 is moved for a desired time. The operation of exposing only for all lines is performed for each color.

Next, the printer unit 2 of the photographic processing apparatus 1
The operation related to the exposure in the above will be described with further reference to FIG. FIG. 3 is a schematic diagram illustrating a manner in which light of three colors of RGB is refracted by the prism 36 when exposing an image for one line.

As shown in FIG. 3A, the color wheel 2
When the blue (B) filter 24a exists on the optical axis due to the rotation of the optical lens 4, the optical shutter 34 and the exposure lens 3
The blue light transmitted through 5 travels straight without being substantially refracted by the prism 36. Thereby, the small area 61 on the photographic paper 6 in the light emission direction of the halogen lamp 23
Are exposed with blue light.

Next, as shown in FIG. 3B, the green (G) filter 24 is placed on the optical axis by the rotation of the color wheel 24.
When b is present, the green light transmitted through the optical shutter 34 and the exposure lens 35 is refracted by the prism 36 in the same direction as the traveling direction of the printing paper 6 (indicated by an arrow in FIG. 3B). . In consideration of the rotation speed of the color foil 24, the conveyance speed of the printing paper 6, and the distance between the prism 36 and the printing paper 6, the prism 36 has a refraction angle at which the green light emitted from the prism 36 is The angle is designed so as to reach the small area 61 slightly moved to the left above. As a result, the small area 61 on the photographic paper 6 that has moved to the left as compared to when exposed with blue light is exposed with green light.

Next, as shown in FIG. 3C, the rotation of the color wheel 24 causes the red (R) filter 24 to be placed on the optical axis.
When c is present, the red light transmitted through the optical shutter unit 34 and the exposure lens 35 is refracted by the prism 36 in the same direction as the traveling direction of the printing paper 6 (indicated by an arrow in FIG. 3C). . In consideration of the rotation speed of the color wheel 24, the conveying speed of the printing paper 6, and the distance between the prism 36 and the printing paper 6, the prism 36 has a refraction angle at which the red light emitted from the prism 36 is The angle is designed so as to reach the small area 61 further moved leftward. As a result, the small area 61 on the photographic paper 6 that has moved to the left from the exposure with the green light is exposed with the red light.

Up to this point, exposure for one line has been completed, and the same operation is performed for all lines constituting one two-dimensional image, thereby exposing one frame of the print image. .

As described above, according to the exposure apparatus of the present embodiment, the three colors of RGB light reach the same small area 61 despite the continuous relative movement of the printing paper 6 with respect to the light source side. And color registration due to a shift in the exposure position does not occur. Therefore, the sharpness and the maximum density of the print image are not degraded, and the print image is not uneven, so that a print image with excellent image quality can be obtained. Moreover, photographic paper 6
Is moved relative to the light source side continuously rather than intermittently, so that there is an advantage that the time required for exposing one image does not become longer and excellent processing performance can be maintained. .

The configuration of the exposure apparatus of the present embodiment is as follows.
This can be realized only by adding the prism 36 having the above-described characteristics to the conventional exposure apparatus, and has the advantage that the structure is relatively simple.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a schematic view illustrating a main part of the exposure apparatus of the present embodiment, and corresponds to FIG. 3 in the first embodiment. The exposure apparatus of the present embodiment is configured by integrating the exposure lens 35 and the prism 36 used in the first embodiment into one prism 71, and the other configuration is the same as that of the first embodiment. This is almost the same as the embodiment.

The prism 71 used in the exposure apparatus of the present embodiment is the same as that of the exposure lens 35 of the first embodiment.
Is an optical element having both the image forming function of the optical head and the refraction function of a different refractive index for each of the three colors of RGB.
1 will be configured. Therefore, according to the present embodiment, it is not necessary to form the exposure lens 35 and the prism 36 as separate members as in the first embodiment, and these functions can be realized by one member. So
The size of the exposure apparatus can be reduced.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 5 is a schematic perspective view illustrating a main part of the exposure apparatus of the present embodiment.
In the present embodiment, a DMD 84 that sequentially reflects light from a light source line by line is used as a light control unit.
Other configurations are almost the same as those of the first embodiment.

In FIG. 5, the light emitted from the halogen lamp 23 passes through one of the RGB filters by the color wheel 24, is converted into parallel light by the collimator lens 81, and enters the DMD 84. The DMD 84 can reflect incident light in a desired direction by individually controlling the inclination angles of a large number of micromirrors 84a. In the present embodiment, the micromirrors 84a are arranged in a plane in a matrix. It is a spatial light modulator. Therefore, the reflection angle of each micromirror 84a is, for example, DMD8
The plurality of micromirrors 84a in one column of the matrix 4 are controlled so as to correspond to one dot on the printing paper 6. As a result, the time required for exposing the photographic paper 6 is shortened, so that the transport speed of the photographic paper 6 can be increased to further improve the processing capability of the apparatus.

The light reflected by the DMD 84 passes through the exposure lens 85 and the prism 86 and is given to the printing paper 6. The rhythm 86 in the present embodiment has a different refractive index according to each of the RGB colors, similarly to the prism 36 of the first embodiment. The refractive index of each color is adjusted so that color registration does not occur even if the photographic paper 6 continuously moves relative to the light source side.

Therefore, according to the present embodiment, it is possible to obtain a print image of excellent image quality without deteriorating sharpness, maximum density, or unevenness of the image while maintaining excellent processing performance.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes may be made within the scope of the appended claims. Is possible. For example,
In the above-described embodiment, an optical shutter or a DMD having a PLZT element is used as the light control means. However, a liquid crystal display, a liquid crystal shutter array, or the like can be used as the light control means. Further, as the light source unit that sequentially emits light of a plurality of colors, for example, an LED that can emit RGB light can be used in addition to the one using a color foil.

Further, in the above-described embodiment, the refraction means such as a prism is arranged after the light control means. However, the refraction means may be arranged before the light control means. In the above embodiment, the prism is RG
Although the three colors B have different refractive indices, the refractive index of the prism may be adjusted for light of other colors. Further, the photosensitive material is not limited to photographic paper, but may be a photosensitive drum used in an electronic copying machine.

[0045]

As described above, according to the first and second aspects, even when the photosensitive material is continuously moved relative to the light source, the color resist is more than when the optical element is not present. Therefore, it is possible to obtain a high-quality image that does not cause deterioration in sharpness while maintaining relatively high processing performance.

According to the third aspect, color registration is eliminated, and a higher quality image can be obtained. According to the fourth aspect, since it is not necessary to form the refraction means as a member separate from the exposure lens for imaging, the size of the apparatus can be reduced. According to the fifth aspect, since the refraction means is a lens or a prism, the refraction means can be easily configured. According to the sixth aspect, by forming one dot of the photosensitive material using a plurality of pixels of the light control means, it is necessary to perform exposure more than when forming one dot of the photosensitive material using one pixel of the light control means. The time can be shortened, and the processing capacity can be further improved.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a schematic configuration of a photographic processing apparatus in which an exposure apparatus according to a first embodiment of the present invention is incorporated.

FIG. 2 is a block diagram of a control system of the photographic processing apparatus shown in FIG.

FIG. 3 is a schematic diagram illustrating a manner in which light of three colors of RGB is refracted by a prism when exposing an image for one line according to the first embodiment of the present invention.

FIG. 4 is a schematic diagram illustrating a main part of an exposure apparatus according to a second embodiment of the present invention.

FIG. 5 is a schematic perspective view illustrating a main part of an exposure apparatus according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Photo processing apparatus 2 Printer part 3 Processor part 4 Finishing part 6 Printing paper 23 Halogen lamp 24 Color foil 25 Print head 34 Optical shutter part 35 Exposure lens 36 Prism

Claims (6)

[Claims] 1. An exposure apparatus for sequentially exposing a photosensitive material continuously moving relative to a light source unit with light of a plurality of colors, wherein an exposure position shift of the light of the plurality of colors on the photosensitive material due to the relative movement. An exposure apparatus, comprising: an optical element having a different refractive index for each of the plurality of colors of light so that is smaller. 2. A light source unit for sequentially emitting light of a plurality of colors, and a light control unit for selectively reflecting or transmitting the light of the plurality of colors from the light source unit for each line constituting two-dimensional image data. Position changing means for continuously moving the photosensitive material relative to the light source unit; and the plurality of colors are arranged such that a shift in the exposure position of the plurality of colors of light on the photosensitive material due to the relative movement is reduced. And a refracting means having a different refractive index for each light. 3. The refracting means has a different refractive index for each of the plurality of colors of light so as to eliminate the exposure position shift of the plurality of colors of light on the photosensitive material due to the relative movement. The exposure apparatus according to claim 2, wherein: 4. An exposure apparatus according to claim 2, wherein said refraction means has a function of forming an image of light on a photosensitive material. 5. The refracting unit according to claim 2, wherein the refracting unit includes one of a lens and a prism having different refractive indexes for the lights of the plurality of colors. Exposure equipment. 6. The exposure apparatus according to claim 2, wherein one dot formed on the photosensitive material corresponds to a plurality of pixels of the light control means.