JPH11221942A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming apparatus producing a high quality print in which fluctuation of gray level due to characteristic fluctuation is suppressed while enhancing recording energy and recording speed. SOLUTION: An image forming apparatus comprises a plurality of optical recording heads each having one or a plurality of recording element array including at least two optical recording heads controlling a light of same color wherein an image is formed by exposing a silver halide color photosensitive material moving relatively to the optical recording heads. In such an image forming apparatus, at least two optical recording heads controlling a light of same color are juxtaposed at substantially identical positions for recording in the direction perpendicularly to the moving direction of the silver halide color photosensitive material so that an image data of same color can be recorded by means of a plurality of heads.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for recording an image on a silver halide photographic material in accordance with image data, and more particularly, to a direction perpendicular to the arrangement direction of recording elements by using recording elements arranged in an array. The present invention relates to an apparatus for recording an image on a silver halide photographic material which moves relatively to the image.

[0002]

2. Description of the Related Art As an apparatus for recording an image in accordance with image data, a system for thermally transferring ink from an ink holding sheet, an ink jet system for spraying ink droplets from nozzles, an electrophotographic system for electrostatically attaching toner particles, and a silver salt A silver halide photographic system in which a dot image is exposed on a light-sensitive material is known.

In recent years, in particular, the use of recording from color image data has been increasing, and accordingly, high-quality color image recording has been demanded. Regarding the image quality of the recorded image, color reproducibility, gradation, sharpness, etc. From the viewpoint of evaluation, the level of evaluation is increasing. Under such circumstances, the silver halide photographic method has attracted attention as a high-quality image recording method.

In a system in which a dot image is exposed to a silver halide photographic material based on image data, the apparatus is inexpensive and compact, and a large number of light emitting elements are arranged in an array in such a manner that there are many advantages that a large size output can be easily handled. A system using an arrayed light source is known. LED arrays, vacuum fluorescent print heads (Vac
uum Floursent Print Hea
d; hereinafter simply referred to as VFPH), JP-A-62-134.
No. 624, a combination of a light source and a liquid crystal shutter array, and a combination of a light source and a PLZT shutter array described in JP-A-63-189269 are used.

Conventionally, image exposure of a silver halide photographic material using such an array light source is performed by simultaneously driving the light emitting elements of the array light source to simultaneously perform linear dot image exposure and at the same time relative to the array light source. By moving the silver halide light sensitive material in a direction perpendicular to the arrangement direction of the light emitting elements, two-dimensional dot image exposure is performed on the silver halide light sensitive material and image recording is performed.

[0006]

However, since the recording heads constituting these arrays have variations in control characteristics, the recording energies are different even when driven by the same signal. Therefore, when recording is performed on a silver salt photographic material which moves relatively, streak-like unevenness (unevenness of light and shade) due to the energy difference of the printing element is caused, and the image quality is deteriorated. For example, there is a problem that the light emission luminance is different for the same signal in an LED array as a light emitting element or the above-described VFPH, and the transmittance is different for the same signal in a PLZT shutter array or a liquid crystal shutter array.

For this reason, it is necessary to correct variations in the characteristics of each element, which is extremely time-consuming. In addition, an expensive jig is required in the device manufacturing process for high-precision correction, which causes trouble and an increase in manufacturing cost.

In addition, even if the variation of the correction of the elements is corrected, the characteristics are different from element to element over time.
There is a problem that the streak-like unevenness (shading unevenness) increases with time, and the image quality deteriorates. In addition, if a built-in device that measures the variation of each element to maintain image quality is built in, the size of the device will increase and the cost will increase significantly.If maintenance is performed such as periodically updating correction values by a maintenance man, And various problems such as an increase in maintenance cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and provides an image forming apparatus which has a high recording energy, enables high-speed operation, and can obtain a high-quality print with small density unevenness due to characteristic variations. It is intended to provide. Another object of the present invention is to provide an image forming apparatus capable of obtaining high-quality prints with stable sharpness and gradation.

[0010]

In order to achieve the above object, the present invention comprises a plurality of optical recording heads having recording elements arranged in an array of one or more rows, and the plurality of optical recording heads are provided. At least two of the recording heads are optical recording heads for controlling the same color light, and an image is formed by exposing a silver halide color photosensitive material that moves relatively to the optical recording head to form an image. In the apparatus, at least two of the optical recording heads controlling the same color light
The books are arranged side by side so that the recordable areas in the direction orthogonal to the moving direction of the silver halide color light-sensitive material are substantially the same, and image data of the same color can be recorded by a plurality of heads. It was configured as follows.

According to a second aspect of the present invention, there is provided an optical recording head having a control unit for processing the same image data to divide the data into a plurality of data, and controlling the plurality of data with the same color light. Recording is performed in a direction perpendicular to the moving direction of the silver halide color light-sensitive material by at least two of them arranged in parallel at the same position, and recording energy due to variation in characteristics of recording elements of each head. And the variation of the variation with the lapse of time are configured to be canceled by each head.

Furthermore, in the invention according to claim 3, at least the cyan image recording head is a direction perpendicular to the moving direction of the silver halide color photosensitive material among the optical recording heads controlling the same color light. Characterized in that at least two are arranged side by side at substantially the same position where
The configuration is such that the cost can be reduced by the visibility of the cyan image.

Further, in the optical recording head of the present invention, at least a head for recording the magenta image controls the color light of the same color, a direction perpendicular to the moving direction of the silver halide color photosensitive material. And at least two of them which are juxtaposed at substantially the same position where recording is possible, and the cost is reduced by the visibility of the magenta image.

[0014]

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view of an image printer to which the present invention is applied, FIG. 2 is a schematic perspective view of a first example in which an optical recording head is enlarged, and FIG. FIG. 4 is an enlarged explanatory view showing the relationship between a silver halide color light-sensitive material (photographic paper) and a recording head, and FIG. 5 is a view in which the recording head is arranged in a V-shape. And FIG. 6 is a view showing a flowchart of a control system.

Image printer body 1 to which the present invention is applied
As shown in FIG. 1, the image information captured by the scanner 5 is recorded by the optical recording head 6 on the photographic paper 4 pulled out from the photographic paper magazine 2 by the transport means 3 and then transported to the developing processing unit 7. It is configured so that it can be developed, cut into a predetermined size by a cutter 8 and discharged onto a discharge tray 9. Needless to say, the cutting may be performed before the sheet is conveyed to the developing unit 7.

As shown in FIGS. 2 and 3, the optical recording head 6 is a photographic paper, which is a color silver halide photographic material drawn out by driving rollers 3a and 3b rotating in connection with a driving source (not shown). When 4 is conveyed in the direction of the arrow, red light source print heads 10a and 10a 'having an LED array, green light source print heads 10b and 1b having a vacuum fluorescent tube array are provided.
The image output control section 11 controls the exposure of the print heads 0b 'and the blue light source print heads 10c and 10c' in accordance with the image data R, G, and B, so that a predetermined position of the printing paper 4 is exposed for each color. When the exposure process is completed, the photographic paper 4 is conveyed to the developing unit 7 as described above, and an output image is obtained through a predetermined developing process.

As shown in FIG. 4, a plurality of recording elements arranged in an array of one row or a plurality of rows are used for each of the heads 6, and the red light source print head 10a has an LED having a recording element density of 300 dpi. A combination of the cell hook lens arrays as the imaging optical systems 13a and 13a 'is adopted for the arrays 12 and 12'.

The green light source print head 10
b, 10b 'and blue light source print heads 10c, 10c
c 'is a 300 dpi vacuum fluorescent tube array 14a, 14
Filters 15a, 15a ', 15b, and 15a, 15a', 15b, for color separation are respectively provided in vacuum fluorescent tube print heads in which a cell hook lens array is combined as imaging optical systems 13b, 13b ', 13c, 13c' on a ', 14b, 14b'. Fifteen
The combination of b 'is employed.

The vacuum fluorescent tube arrays 14a, 14
a ′, 14 b, 14 b ′ and a cell hook lens array (imaging optical system) 13 are combined with the “VF” described above.
PH ". Although the photographic paper 2 has been described as a roll, it may be cut paper.

The transport means 3 for the photographic paper 2 is not limited to the drive rollers 3a and 3b shown in FIGS. Further, a method in which the printing head is moved while the printing paper 2 is fixed, or a method in which the printing paper and the printing head move together may be used. Further, the image forming optical system of the recording element is not limited to the cell hook lens array, but may be a roof mirror lens array or the like.

Next, the recording operation will be described with reference to FIG. When performing color recording for one line at the point a of the photographic paper 4, first, the image output control unit 11 sends one line of red image data R, green image data G, and blue color to each optical recording head 6. The image data B is transferred. Conveying means 3
Transports the photographic paper 4 at a constant speed in the direction of the arrow, and when the point a reaches the image forming point of the red light source print heads 10a and 10a ', under the control of the print head controller 11, Red light source print heads 10a, 10
a 'performs exposure according to the image data and records the red image data on the photographic paper 4.

Then, as the photographic paper 4 is sequentially conveyed, the point a is set to the green light source print heads 10b and 1b, respectively.
0b 'imaging point,', blue light source printhead 10
Exposure control similar to the above is performed in accordance with the timing of reaching the image forming points c and 10c ', and
Do on a point. By repeating such an operation for all lines, a color image can be recorded in a predetermined area on the photographic paper 4.

FIG. 5 shows a red light source print head 10.
a, 10a ', green light source print heads 10b, 10b
b ′, and blue light source print heads 10c, 10c ′, each pair of heads are installed in a V-shape, and the respective imaging points are
, Etc. are shown. The description of FIG. 4 can be referred to for the recording operation.

In FIGS. 4 and 5, the recording element is one of the image data.
The recording operation has been described as an example of an array in which lines are arranged. However, even in an array in which a plurality of recording elements are arranged or an array in which a two-dimensional panel is arranged, the image forming position of each print head is determined by the recording position on photographic paper. By appropriately setting the timing and performing exposure control, a color image can be recorded.

Further, as another embodiment of the present invention, LE
Similar effects can be obtained even when image recording is performed by combining a shutter array such as a backlight, a filter, a liquid crystal shutter array, and a PLZT (lead, lanthanum, zirconium, titanium, composite oxide) optical shutter array in addition to D. Is possible.

Next, the image data R, G,
The principle of distributing B to a plurality and transferring to each system of each head
A description will be given based on FIG. The same color image data R, G,
B is subjected to data processing by the central control unit 100 and divided into a plurality of (two in this example) data R ₁ and R ₂ , G ₁ and G ₂ , B ₁ and B ₂ , and image data distribution units 101 a, 101 b, and 1.
01c arranged side by side so as to be almost at the same position
Print heads 10a and 10a ', 10b and 1 for each book
0b ', 10c and 10c', respectively.

Here, the halved data is sent to each system of the head. However, as another example, distribution according to the average light emission luminance ratio of each head and odd-numbered pixels are heads of the first series, even-numbered pixels. May be distributed to the second series of heads and blocks.

The distributed data R ₁ and R ₂ , G ₁ and G
_2, B ₁ and B ₂ are characteristic variation correction portion 102a and 102a of each recorded image element by element in each head based ', 1
02b and 102b 'and 102c and 102c'
The correction is performed based on the variation correction data of each head.
Here, the image data is multiplied by using the reciprocal of the emission luminance ratio of each element with respect to the average luminance of all elements for each head as a coefficient. As another example, it is needless to say that addition may be performed.

The image data corrected in this way is a VFP
The data is sent to the H control unit 11 and converted into control data of each element of each head in the VFPH control unit 11, and each head is driven as described above.

As described above, the same color image data is recorded by a plurality of heads. First, the recording energy is increased and the recording speed is increased (eg, 60 mm / sec or more).
Second, variations in the recording energy due to variations in the characteristics of the recording elements of the respective heads and changes with time in the variations due to the respective heads are canceled out by each head, and as a result, line unevenness due to the variations in the characteristics is obtained. The unevenness of shading is reduced (the effect is larger than that of a single head device), and stable high-quality printing can be obtained. Third, the focus direction when the head and the photosensitive material are relatively moved. The sharpness and gradation change due to the difference in the image structure due to the variation of the image can be canceled out by a plurality of heads. As a result, it is possible to obtain a high-quality print with the same sharpness and gradation. That's because.

In the above description, the image data is divided into two parts, and the red light source print heads 10a and 10a 'having LED arrays 12 and 12', respectively, and the green light source print heads having vacuum fluorescent tube arrays 14a and 14a '. 10b, 10b 'and vacuum fluorescent tube array 14b, 1
Blue light source print heads 10c, 10b having 4b '
Although the image data is distributed to two series of c ′, the image data is distributed to a plurality of three or more, and each head is made to be three or more in accordance with the distribution number of the image data (the more the number, the more the head). Although it is preferable in that the canceling effect increases, it is unavoidable that the cost increases, so that the optimal number is determined.

However, in the head for recording the magenta image of the image data G or the head for recording the cyan image of the image data R, the above-described canceling effect can be sufficiently realized with a small number (at least two) due to its visibility. It is better to determine the minimum number.

[0033]

As described above, the present invention has a plurality of optical recording heads having recording elements arranged in an array of one row or a plurality of rows, and among the plurality of optical recording heads,
At least two optical recording heads for controlling color light of the same color, and in an image forming apparatus that forms an image by exposing a silver halide color photosensitive material that moves relatively to the optical recording head, At least two of the optical recording heads for controlling the color light are arranged in parallel so that the recordable areas in the direction perpendicular to the moving direction of the silver halide color light-sensitive material are substantially the same. Therefore, the recording energy is increased and the speed can be increased. In addition, variations in the recording energy due to variations in the characteristics of the recording elements of the respective heads and changes with time in the variations due to aging are different for each head. As a result, the heads cancel each other out. High quality prints can be obtained. In addition, a change in sharpness and gradation due to a difference in image structure due to a variation in the focus direction when the head and the photosensitive material move relative to each other also results in a plurality of heads canceling each other out. And various other excellent effects, for example, a stable high-quality print can be obtained.

According to a second aspect of the present invention, there is provided an optical recording head having a control unit for processing the same image data to divide the data into a plurality of data, and for controlling the plurality of data to the same color light. 2. The recording medium according to claim 1, wherein the recording is performed in a direction perpendicular to the moving direction of the silver halide color light-sensitive material with at least two of the two lines arranged at the same position. Is played.

Further, in the invention according to claim 3, at least the cyan image recording head is a direction perpendicular to the moving direction of the silver halide color photosensitive material among the optical recording heads controlling the same color light. Since at least two of the heads are arranged side by side at substantially the same position that can be recorded on a cyan image, the number of the cyan image recording heads is small (at least two) due to the visibility of the cyan image. The same effect as the invention of item 1 can be realized at low cost.

Still further, according to a fourth aspect of the present invention, in the optical recording head in which at least a magenta image recording head controls the same color light, a direction orthogonal to a moving direction of the silver halide color photosensitive material. And at least two (at least two) heads for recording the magenta image due to the visibility of the magenta image due to the visibility of the magenta image. The same effect as that of the invention can be realized at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of an image printer to which the present invention is applied.

FIG. 2 is a schematic perspective view of a first example in which an optical recording head is enlarged.

FIG. 3 is a schematic perspective view of a second example in which the optical recording head is enlarged.

FIG. 4 is an enlarged explanatory view showing a relationship between a silver halide color photosensitive material (photographic paper) and a recording head.

FIG. 5 is an enlarged explanatory view showing a modification of FIG. 4 in which recording heads are arranged in a V-shape.

FIG. 6 is a view showing a flowchart of a control system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Image printer main body 2 Printing paper magazine 3 Conveying means 3a, 3b, drive roller 4 Printing paper (silver halide color photosensitive material) 5 Scanner 6 Optical recording head 7 Development processing part 8 Cutter 9 Discharge tray 10a Red light source print head 10b Green light source print head 10c Blue light source print head 11 Image output control unit (VFPH control unit) 12 LED array 13 (13a, 13b, 13c) Imaging optical system 14a, 14a ', 14b, 14b' Vacuum fluorescent tube array 15a, 15a , 15b, 15b 'Filter for color separation 100 Central control unit 101a, 101b, 101c Image data distribution unit 102a, 102a', 102b, 102b ', 102
c, 102c 'Element-specific characteristic variation correction unit

Claims (4)

[Claims] An optical recording head having a plurality of recording elements arranged in an array of one or a plurality of rows, wherein at least two of the plurality of optical recording heads control light of the same color. An image forming apparatus that forms an image by exposing a silver halide color photosensitive material that moves relative to the optical recording head, wherein the optical recording head controls the same color light. Of which at least 2
An image forming apparatus, wherein books are arranged side by side so that recordable areas in a direction orthogonal to a moving direction of the silver halide color light-sensitive material are substantially the same. 2. A control unit for processing the same image data to divide the data into a plurality of data, and arranging the plurality of data at the same position in an optical recording head for controlling the same color light. 2. The image forming apparatus according to claim 1, wherein the recording can be performed in a direction orthogonal to a moving direction of the silver halide color light-sensitive material by using at least two of the two. 3. At least a cyan image recording head is arranged at substantially the same position in the optical recording head that controls the same color light, at which recording is possible in a direction orthogonal to a moving direction of the silver halide color photosensitive material. The image forming apparatus according to claim 1, wherein the number is at least two. 4. A head for recording at least a magenta image,
Among the optical recording heads controlling the same color light, at least two optical recording heads are juxtaposed at substantially the same position where recording is possible in a direction orthogonal to the moving direction of the silver halide color photosensitive material. The image forming apparatus according to claim 1.