JP2000229445A - Led array printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an LED array printer capable of suppressing deviation and variation in a light quantity distribution of each LED element and to prevent occurrence of a vertical stripe in an image. SOLUTION: As an emission intensity of an LED element 16 is raised at a portion of an individual electrode provided to a light emitting section 20, the each individual electrode 21a, 21b is divided into plural parts to be provided to each LED element 16 and the arrangement, shape and energizing quantity are controlled so that deviation and variation in a light quantity distribution of each LED element 16 can be suppressed, thereby preventing occurrence of a vertical stripe such as a whiter stripe or a black stripe in an image. As the individual electrodes 21a, 21b are controlled independently, dots of which number is the same as the number of individual electrodes 21a, 21b can be formed so that the resolution in appearance can be raised.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an LED array printer for forming an image by electrophotography using an LED array head as optical writing means.

[0002]

2. Description of the Related Art In recent years, attention has been paid to an LED array printer using an LED array head as optical writing means in order to reduce the size and simplify the apparatus. The LED array is formed by arranging a large number of LED elements in a line along the main scanning direction, and by performing lighting control on each LED element according to image information, optical writing on a photoconductor is performed. An electrostatic latent image is formed.

[0003] It is practically impossible to manufacture an LED array so that all of its characteristics are uniform with respect to a large number of LED elements. Therefore, the amount of light is different for each LED element, and the dot diameter to be formed is also different for each LED element. Depends on the element. Naturally, image density unevenness occurs due to variation in the light amount of each LED element. However, in a printer of a method of expressing gradation by an area gradation method in a one-dot binary recording method, a variation in dot diameter causes a variation in density. And the image quality of the gradation expression is degraded. In an LED array printer, printing is performed by the same LED element in the sub-scanning direction. Therefore, if there is a variation in the dot diameter, a vertical streak occurs in a vertical line (sub-scanning line) image. The vertical streak includes a white streak in which an image is lost in white, and a black streak (a streak having a higher density than others) due to a narrowing (overlap) between dots.

For this reason, Japanese Patent Application Laid-Open No. Hei 5-50653 discloses an LED array printer using an LED array head corrected so that the light amounts of all the LED elements are all uniform. According to Japanese Patent Application Laid-Open No. 5-50653, correction data for making the light amount of each LED element constant is obtained in advance, and a ROM storing the correction data is provided in the LED array head. Each LED element is turned on using the LED.

However, optical image data emitted from each LED element is formed as a latent image on a photoreceptor through a lens array. It is impossible to make the light amount distribution of the image uniform, and as a result, vertical stripes occur on the image.

FIG. 34 shows a light amount distribution and a dot shape to be formed in the case of a vertical image every other line in the sub-scanning direction (lighting every other dot in the main scanning direction).
When the light amount distribution of the ED element varies, the line interval becomes wider or the line interval becomes narrower (overlaps), and white stripes and black stripes are generated.

Usually, as shown in FIG. 35 (a), in the LED array, the light emitting portions 102 of a plurality of LED elements 101 are arranged in a straight line on a base substrate 103, and each LED element 1
The structure is such that the individual electrode 104 is drawn out from the light emitting section 102 of the light emitting element No. 01. Therefore, when a voltage is applied to the individual electrode 104, the LED element 101 emits light.
Since the current density is higher in the vicinity, the light emission intensity in the vicinity of the individual electrode 104 is higher, and the light emission distribution of the light emitting unit 102 as a whole is biased. When the individual electrodes 104 are alternately drawn out and arranged in different directions as shown in FIG. 35 (a), the center of light emission of the adjacent LED elements 101 becomes the center of FIG.
As shown in FIG. 35 (b), the pattern becomes staggered, and as a result, FIG. 35 (c)
As shown in (1), the image shifts and a step occurs. Also,
Since the centers of light emission of the adjacent LED elements 101 are shifted in the sub-scanning direction, dots do not overlap depending on the spot diameter of the LED elements 101, and white stripes and shading occur in an image.

For these reasons, Japanese Patent Application Laid-Open No. 63-47-1988
According to Japanese Patent No. 77, the positions of the light emitting portions of the front and rear LED elements adjacent to each other are alternately shifted left and right with respect to the center line, and the LED elements are arranged along the length direction of the base substrate. By aligning the portion on the individual electrode side where the light emission intensity of the LED element is maximum on the center line, the light distribution of the band-shaped irradiation portion composed of a plurality of LED elements along the center line is made uniform, and the distance between each LED element is increased. In this case, no shift occurs in the light amount distribution at the time of printing, and the shift of the print character is eliminated.

[0009]

However, there is a problem that it becomes extremely complicated as compared with the case where the light emitting portions of the respective LED elements are arranged in a straight line on the base substrate. In addition, it is difficult to completely eliminate the shift of the light amount distribution because the LED elements are arranged after predicting the shift of the light amount distribution in advance and cannot be adjusted after the arrangement.

In view of the above, the present invention provides a light emitting portion of a large number of LED elements arranged in a line along the main scanning direction.
In the LED array printer that controls the lighting of the D element according to the image information and forms a latent image corresponding to the image information on the image carrier, attention is paid to the point that the light emission intensity near the individual electrode is increased. By devising the electrodes, each LE
The bias and variation of the light amount distribution in the D element are reduced,
An object of the present invention is to provide an LED array printer capable of suppressing the occurrence of vertical stripes or the like on an image.

In addition, the present invention controls a plurality of individual electrodes on a light emitting portion of each LED element, so that a light quantity distribution, a light quantity, a spot diameter, and the like in each LED element and its individual electrodes are controlled.
Alternatively, it is another object of the present invention to provide an LED array printer that can suppress the occurrence of vertical stripes on an image by setting a pitch between spots of each LED element to a desired shape or a desired value.

Another object of the present invention is to provide an LED array printer capable of increasing the apparent resolution by utilizing the individual electrodes.

Further, the present invention provides a method of forming dots,
An object of the present invention is to provide an LED array printer capable of increasing the margin, stabilizing the image quality, and simplifying the entire control system.

[0014]

According to the first aspect of the present invention,
The light-emitting portions of a large number of LED elements are arranged in a line along the main scanning direction, and each LED element is controlled to be turned on according to image information, and a latent image corresponding to the image information is formed on an image carrier. In the LED array printer, a plurality of individual electrodes are provided for the light emitting portion of each LED element.

Therefore, in the LED element, the light emission intensity is increased at the individual electrode portion provided for the light emitting portion. Therefore, by providing the individual electrodes for each LED element in a state of being divided into a plurality of individual electrodes, their arrangement is made. By controlling the shape, the amount of electricity, and the like, it is possible to suppress the deviation and variation in the light amount distribution of each LED element, and to suppress the occurrence of vertical stripes such as white stripes and black stripes on an image. Also, each L
Since a plurality of individual electrodes are provided for each light emitting portion of the ED element, it is possible to form dots by the number of individual electrodes by controlling them individually, and it is possible to increase the apparent resolution. This means that when a gray scale is expressed by an area gray scale method such as an error diffusion method in a one-dot binary system, the gray scale can be improved.

The invention according to claim 2 is the invention according to claim 1,
In the ED array printer, the individual electrodes of the respective LED elements are provided so as to be divided at both ends of the light emitting section in the main scanning direction.

Therefore, in order to realize the first aspect of the present invention, as an example, since the individual electrodes are provided at both ends of the light emitting portion in the main scanning direction, the light amount of each LED element in the main scanning direction is provided. Unevenness and variation in distribution can be suppressed, so that occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed.

The invention according to claim 3 is the invention according to claim 1,
In the ED array printer, the individual electrodes of the respective LED elements are provided so as to be divided into both ends of the light emitting unit in the main scanning direction and an intermediate part thereof.

Therefore, in order to realize the first aspect of the present invention, as an example, in particular, since the individual electrodes are provided at both ends of the light emitting portion in the main scanning direction and at an intermediate portion thereof, each of the light emitting portions is provided.
Unevenness and variation of the light amount distribution of the ED element in the main scanning direction can be suppressed, and therefore, occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed. In particular, since the individual electrodes are also provided in the middle part in the main scanning direction, the bias can be further suppressed.

The invention according to claim 4 is the invention according to claim 1,
In the ED array printer, the individual electrodes of the respective LED elements are provided so as to be divided with respect to both ends of the light emitting section in the sub-scanning direction.

Accordingly, in realizing the first aspect of the present invention, as one example, since the individual electrodes are provided at both ends of the light emitting section in the sub-scanning direction, the light amount of each LED element in the sub-scanning direction is provided. Unevenness and variation in distribution can be suppressed, so that occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed.

The invention according to claim 5 is the invention according to claim 4, wherein
In the ED array printer, the individual electrodes of each of the LED elements are divided with respect to both ends of the light emitting unit in the main scanning direction.

Therefore, in realizing the invention according to claim 4, as an example, in particular, the individual electrodes provided at both ends in the sub-scanning direction of the light emitting section are divided with respect to both ends in the main scanning direction. And four individual electrodes, each L
It is possible to suppress deviations and variations in the light amount distribution of the ED element in the main scanning direction and the sub-scanning direction, and thus it is possible to suppress the occurrence of vertical stripes such as white stripes and black stripes on an image.

According to the sixth aspect of the present invention, the L
In the ED array printer, the individual electrodes of each of the LED elements are divided with respect to both ends in the sub-scanning direction of the light emitting unit.

Therefore, in order to realize the third aspect of the present invention, as an example, in particular, the individual electrodes provided at both ends of the light emitting portion in the main scanning direction and the intermediate portions thereof are arranged with respect to both ends in the sub-scanning direction. Since the individual electrodes are divided into six individual electrodes, deviations and variations in the light amount distribution of each LED element in the main scanning direction and the sub-scanning direction can be suppressed as much as possible. It is possible to suppress the occurrence of vertical streaks such as streaks.

The invention according to claim 7 is the invention according to claims 1 to 6
In the LED array printer according to any one of the above, an energizing operation of each of the LED elements to the plurality of individual electrodes on the light emitting unit is controlled so that a light amount distribution of each of the LED elements has a desired shape. .

Therefore, by controlling the energizing operation of the plurality of individual electrodes on the light emitting portion of each LED element so that the light quantity distribution of each LED element has a desired shape, the light quantity distribution can be made uniform. Therefore, it is possible to suppress the occurrence of vertical stripes such as white stripes and black stripes on the image.

[0028] The invention according to claim 8 provides the invention according to claims 1 to 6.
In the LED array printer according to any one of the above, a storage unit that stores correction data for making a light amount distribution of each of the LED elements that are lit by energizing the individual electrode into a desired shape, and corresponds to each of the LED elements. Correction data reading means for reading the correction data to be performed from the storage unit; and drive control means for controlling the energizing operation of each of the LED elements to the individual electrodes using the read correction data.

Therefore, when an image is formed by the LED array head, the correction data corresponding to the individual electrode of each LED element is read out from the storage unit, and the drive control means controls the energizing operation to the individual electrode using the correction data. Thus, the light amount distribution of each LED element can be formed in a desired shape, and therefore, the occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed. That is, this is an example for realizing the invention described in claim 7.

According to the ninth aspect of the present invention, there are provided the first to sixth aspects.
In the LED array printer according to any one of the above, the energizing operation of the plurality of individual electrodes on the light emitting unit of each of the LED elements is controlled so that the light amount distribution in each of the individual electrodes of each of the LED elements has a desired shape. It was made to be.

Therefore, by controlling the energizing operation of the plurality of individual electrodes on the light emitting portion of each LED element so that the light quantity distribution at each individual electrode of each LED element has a desired shape, the light quantity distribution is made uniform. So that
It is possible to suppress the occurrence of vertical stripes such as white stripes and black stripes on the image.

According to a tenth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects,
A storage unit that stores correction data for forming a light quantity distribution in each of the individual electrodes of each of the LED elements that are lit by energizing the individual electrodes into a desired shape; and a storage unit that stores correction data corresponding to each of the LED elements. And a drive control means for controlling the energizing operation of each of the LED elements to the individual electrodes using the read correction data.

Therefore, when an image is formed by the LED array head, the correction data corresponding to the individual electrodes of each LED element is read from the storage section, and the drive control means controls the energizing operation to the individual electrodes using the correction data. Thus, the light amount distribution in each individual electrode of each LED element can be formed in a desired shape, and therefore, the occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed. That is, this is an example for realizing the invention described in claim 9.

An eleventh aspect of the present invention provides an LED array printer according to any one of the first to sixth aspects,
An energizing operation of each of the LED elements to the plurality of individual electrodes on the light emitting section is controlled so that the light amount of each of the LED elements becomes a desired value.

Therefore, the distribution can be made uniform by controlling the energizing operation of the plurality of individual electrodes on the light emitting portion of each LED element so that the light quantity of each LED element becomes a desired value. In addition, generation of vertical stripes such as white stripes and black stripes on an image can be suppressed.

According to a twelfth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects,
A storage unit that stores correction data for setting the amount of light of each of the LED elements to be turned on by energizing the individual electrode to a desired value, and a correction data reading unit that reads correction data corresponding to each of the LED elements from the storage unit And drive control means for controlling the energizing operation of each of the LED elements to the individual electrodes using the read correction data.

Therefore, when an image is formed by the LED array head, the correction data corresponding to the individual electrode of each LED element is read from the storage unit, and the drive control means controls the energizing operation to the individual electrode using the correction data. Thus, the light amount of each LED element can be set to a desired value, so that the occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed. That is, this is an example for realizing the invention described in claim 11.

According to a thirteenth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects,
The energizing operation of each of the LED elements on the plurality of individual electrodes on the light emitting section is controlled so that the light quantity at each of the individual electrodes of each of the LED elements becomes a desired value.

Therefore, by controlling the energizing operation of the plurality of individual electrodes on the light emitting portion of each LED element so that the amount of light at each individual electrode of each LED element has a desired value, the amount of light can be made uniform. Therefore, it is possible to suppress the occurrence of vertical stripes such as white stripes and black stripes on the image.

According to a fourteenth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects,
A storage unit that stores correction data for setting a light amount at each of the individual electrodes of each of the LED elements that are turned on by energization to the individual electrodes to a desired value, and a corresponding correction data for each of the LED elements from the storage unit. A read-out correction data read-out unit; and a drive control unit that controls an energization operation of each of the LED elements to the individual electrode using the read-out correction data.

Therefore, when an image is formed by the LED array head, the correction data corresponding to the individual electrodes of each LED element is read from the storage unit, and the drive control means controls the energizing operation to the individual electrodes using the correction data. Thus, the amount of light at each individual electrode of each LED element can be set to a desired value, so that occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed. That is, this is an example for realizing the invention described in claim 13.

According to a fifteenth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects,
An energizing operation of each of the LED elements with respect to the plurality of individual electrodes on the light emitting section is controlled so that the spot diameter of each of the LED elements has a desired value.

Therefore, the spot diameter can be made uniform by controlling the energizing operation of a plurality of individual electrodes on the light emitting portion of each LED element so that the spot diameter of each LED element becomes a desired value. Therefore, it is possible to suppress the occurrence of vertical stripes such as white stripes and black stripes on the image.

According to a sixteenth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects,
A storage unit that stores correction data for setting a spot diameter of each of the LED elements that are turned on by energization to the individual electrode to a desired value, and a correction data readout that reads corresponding correction data for each of the LED elements from the storage unit Means for controlling the energization of the individual electrodes of the LED elements to the individual electrodes using the read correction data.

Therefore, when an image is formed by the LED array head, the correction data corresponding to the individual electrodes of each LED element is read from the storage unit, and the drive control means controls the energizing operation to the individual electrodes using the correction data. Thus, the spot diameter of each LED element can be set to a desired value, and therefore, generation of vertical stripes such as white stripes and black stripes on an image can be suppressed. That is, claim 15
This is an example for realizing the described invention.

According to a seventeenth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects,
An energizing operation of each of the LED elements on the plurality of individual electrodes on the light emitting unit is controlled so that a spot diameter of each of the individual electrodes of each of the LED elements becomes a desired value.

Therefore, by controlling the energizing operation of a plurality of individual electrodes on the light emitting portion of each LED element so that the spot diameter at each individual electrode of each LED element has a desired value, the spot diameter can be made uniform. Therefore, it is possible to suppress the occurrence of vertical stripes such as white stripes and black stripes on the image.

According to the eighteenth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects,
A storage unit storing correction data for setting a spot diameter at each individual electrode of each of the LED elements to be turned on by energizing the individual electrode to a desired value; and a storage unit storing correction data corresponding to each LED element. And a drive control means for controlling the energizing operation of each of the LED elements to the individual electrodes using the read correction data.

Therefore, when an image is formed by the LED array head, the correction data corresponding to the individual electrodes of each LED element is read from the storage unit, and the drive control means controls the energizing operation to the individual electrodes using the correction data. Thus, the spot diameter at each individual electrode of each LED element can be set to a desired value, so that the occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed. That is, this is an example of realizing the invention described in claim 17.

According to a nineteenth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects,
The energizing operation of each of the LED elements to the plurality of individual electrodes on the light emitting section is controlled so that the pitch between the spots of each of the LED elements becomes a desired value.

Therefore, by controlling the energizing operation of a plurality of individual electrodes on the light emitting portion of each LED element so that the pitch between the spots of each LED element becomes a desired value, the pitch between the spots can be made uniform. Therefore, it is possible to suppress the occurrence of vertical stripes such as white stripes and black stripes on the image.

According to a twentieth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects,
A storage unit that stores correction data for setting a pitch between spots of each of the LED elements to be turned on by energization to the individual electrode to a desired value, and correction data that reads correction data corresponding to each LED element from the storage unit A read-out unit; and a drive control unit that controls an energizing operation of each of the LED elements to the individual electrode using the read-out correction data.

Therefore, when an image is formed by the LED array head, the correction data corresponding to the individual electrode of each LED element is read from the storage unit, and the drive control means controls the energizing operation to the individual electrode using the correction data. Thus, the pitch between the spots of each LED element can be set to a desired value, so that the occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed. That is, claim 19
This is an example for realizing the described invention.

According to a twenty-first aspect of the present invention, in the LED eye printer according to any one of the first to twentieth aspects,
The image information is one-dot binary data.

Therefore, in the case where gradation is expressed by the area gradation method using the one-dot binary method, dots are formed at a certain threshold level, so that the amount of light by a plurality of individual electrodes on the light emitting portion is reduced. By setting the threshold level so as not to be affected by the drop, it is possible to prevent the occurrence of white spots in the center of the dot and the density difference between the center of the dot and the peripheral portion. The degree of freedom in setting the threshold level is increased, and the image quality can be further stabilized. In addition, the correction data for making the spot diameters and the like uniform also needs to consider a certain spot diameter and the like, so that the entire control system can be simplified.

[0056]

FIG. 1 shows a first embodiment of the present invention.
This will be described with reference to FIG. This embodiment corresponds to the first, second and twenty-first aspects of the present invention.

First, FIG. 1 shows a configuration example of an image forming unit of the LED array printer according to the present embodiment. The image forming section includes a drum-shaped photoconductor 1 as an image carrier, a charger 2,
It has an LED array head 3 as an image writing unit, a developing unit 4, a transfer unit 5, a cleaning unit 6, and a static eliminator 7, and performs processes of charging, exposure, development, transfer, cleaning, and static elimination, which are normal electrophotographic processes. Then, an image is formed on the recording paper 8 conveyed in the direction of the arrow. With respect to the LED array head 3, image data is sent from an external device, for example, a frame memory, a scanner, or the like, to the LED array control unit 10 according to a control signal from the controller unit 9, and the LED elements are operated in accordance with the image information. Lights up and irradiates the surface of the photoconductor 1 through the lens array. The image forming unit of the LED array printer shown in FIG. 1 is used in another embodiment described later.

FIG. 2 shows the LE in the LED array head 3.
2 shows a configuration example of a D array driving unit 11. The LED array driver 11 has a well-known configuration, and is configured to drive each LED element 16 by a shift register 12, a latch 13, an AND gate 14, and an LED driver 15. The shift register 12 has a line synchronization signal / LSYNC.
The operation is performed such that one-dot binary image data of “0” or “1” is sequentially input from dot 1 by the clock CLOCK, and each dot data is internally sent to each register. When all the dot data of n pieces are sent, the data is latched by the latch 13, and when the strobe pulse STB is input to the AND gate 14, the dot (LED element 16) to which the image data “1” is sent Basically, only the LED driver 15 lights up by the pulse width of the strobe pulse STB.

FIG. 3 shows the drive timing of the LED array head 3. In the present embodiment, as described later, each LED element 16 is provided with two separate electrodes for each LED element 16. Apparently, double dot data is required, and if the above-described basic configuration is used as it is, a shift register, a latch and the like are also required twice.
Therefore, in the present embodiment, when image data is sent to the LED array drive unit 11, the image data is taken in from the outside at half the frequency of the clock CLOCK of the shift register 12 in the LED array drive unit 11, Data is sent to each register in the order of dot 1, dot 1, dot 2, dot 2,... Then, only the dot (LED element 16) to which the image data “1” has been sent is turned on by the two individual electrodes for the pulse width of the strobe signal STB.

FIG. 4 shows a configuration example of the image writing control unit. FIFO (First In Fi)
rst Out) The memory 17 is reset by the main scanning line synchronizing signal / LSYNC from the controller unit 9,
The image data for one line in the main scan is taken. Also, LE
The D array driving section 11 also outputs the main scanning line synchronization signal /
The data is reset by LSYNC, and the image data is sequentially sent from the FIFO memory 17 to the LED array drive unit 11 from the dot 1 at the frequency of 1 or 2 of the clock CLOCK generated from the oscillator 18. Strobe pulse generator 19
Is composed of, for example, a counter, a comparator, etc., and outputs a strobe pulse STB to the LED after all dot data are sent to the shift register 12 and latched.
It outputs to the AND gate 14 of the array driver 11. As a result, a dot whose image data is “1” emits light at the timing of the strobe pulse STB.

FIG. 5 shows a certain L in the present embodiment.
FIG. 6 shows the structure and light amount distribution of the ED element 16 in the vicinity of the light emitting section 20.
FIG. 6A shows a configuration example of an LED array head 3 having many such LED elements 16, and FIG.
6C, the light amount distribution in the main scanning direction of each LED element 16 (Th indicates a threshold level), and FIG. 6D shows the image formation for each LED element 16 in FIG. Here is a dot example. In the present embodiment, the two separate electrodes 21a and 21b are provided on one light emitting unit 20 at both ends in the main scanning direction. Although the common electrode is not shown,
Positions opposite to the individual electrodes 21a and 21b in the sub-scanning direction,
Alternatively, it is installed below the light emitting unit 20 (under the light emitting unit 20). The current density near the individual electrodes 21a and 21b is high,
Since the light emission is strong in the vicinity thereof (part A in FIG. 5 indicates a particularly strong light emission portion), the light quantity distribution in the main scanning direction has a shape having peaks on both sides, and the light quantity distribution in the sub-scanning direction. Is slightly biased in the sub-scanning direction depending on the mounting positions of the individual electrodes 21a and 21b. However, the distribution of the amount of light in the main scanning direction can be controlled by the individual electrodes 21a and 21b provided at the end of the light emitting section 20, so that the bias can be suppressed as compared with the related art. Variations in the light quantity distribution among the 16 light sources can be suppressed.
Further, the light quantity distribution in the sub-scanning direction is slightly biased, and the light quantity distribution between the LED elements 16 is also slightly varied. However, since the bias and variation in the main scanning direction are suppressed, vertical stripes may occur. 6D, an image 22 having no white stripes and no black stripes is obtained. In FIG.
23 is a base substrate.

The dots in FIG. 6 show the case where the gradation is expressed by the area gradation method (such as the error diffusion method) in a 1-dot binary system. Since only one threshold level Th needs to be considered, the control system is simplified, and by setting the threshold level Th that is not affected by the drop in the central part of the light quantity distribution in the main scanning direction, a stable dot is always obtained. Can be formed.

FIGS. 7 and 8 show a second embodiment of the present invention.
It will be described based on. This embodiment relates to claims 3 and 2.
This corresponds to the invention described in 1.

As described above, the image forming section of the LED array printer is the first embodiment (FIG. 1).
It is omitted because it is the same as.

In the present embodiment, since three individual electrodes are provided for one LED element 16 in the present embodiment,
Double the dot data is required, and if the basic configuration is used as it is, the shift register, latch, etc., are also required three times. Therefore, in the present embodiment, when image data is sent to the LED array driving unit 11,
1/3 of the clock CLOCK of the shift register 12
By taking in image data from outside at the frequency of
The image data is sent to each register in the order of dot 1, dot 1, dot 1, dot 2, dot 2, dot 2, dot 3, and so on. Then, “1” of the image data
Only the dot (LED element 16) to which is transmitted is lit by the width of the strobe pulse STB by the three individual electrodes. Therefore, at the drive timing of the LED array head 3 shown in FIG.
Are transmitted at a frequency of 1/2, but in the present embodiment, they are transmitted at a frequency of 1/3, which is different from FIG.

The image writing control unit is the same as that of the first embodiment, and will not be described.
The image data from the O memory 17 is sequentially LED from the dot 1
The difference is that the data is sent to the array driver 11.

FIG. 7 shows a certain L in the present embodiment.
FIG. 8 shows the structure and light amount distribution of the ED element 16 in the vicinity of the light emitting section 20.
FIG. 8A shows a configuration example of an LED array head 3 provided with a large number of such LED elements 16, and FIG.
FIG. 8C shows the light amount distribution in the sub-scanning direction, and FIG.
FIG. 8D shows an example of image forming dots for each LED element 16 in the light amount distribution of the element 16 in the main scanning direction (Th indicates a threshold level). In the present embodiment, three individual electrodes 21a, 21b, and 21c are provided on one light emitting unit 20 at both ends in the main scanning direction and an intermediate part thereof. Although the common electrode is not shown, the individual electrodes 21a, 21b, 2
The light emitting unit 1c is installed at a position opposite to the sub-scanning direction or below the light emitting unit 20 (under the light emitting unit 20). Since the current density in the vicinity of the individual electrodes 21a, 21b, 21c is high and the vicinity thereof emits light intensely, the light quantity distribution in the main scanning direction has an uneven shape, and the light quantity distribution in the sub scanning direction is the individual electrode 2.
Depending on the mounting positions of 1a, 21b, and 21c, they are slightly biased in the sub-scanning direction. However, the distribution of the amount of light in the main scanning direction can be controlled by the individual electrodes 21a, 21b, and 21c provided at both ends and the center of the light emitting unit 20, so that the bias can be suppressed as compared with the related art. Furthermore, compared to the first embodiment, the number of individually controllable electrodes is one.
Since the number of the individual electrodes 21c increases, the bias can be further suppressed, and as a result, the variation in the light amount distribution between the LED elements 16 can be suppressed. Also, the light amount distribution in the sub-scanning direction is slightly biased,
Although the light amount distribution between the elements 16 slightly varies, no vertical streak occurs because the deviation and variation in the main scanning direction are suppressed, and there is no white streak or black streak as shown in FIG. An image 22 is obtained.

The dots in FIG. 8 show the case where gradation is expressed by the area gradation method (such as the error diffusion method) in a one-dot binary system. Since only one threshold level Th needs to be considered, the control system is simplified, and by setting the threshold level Th which is not affected by the drop in the central part of the light quantity distribution in the main scanning direction, a stable dot is always obtained. Can be formed.

FIGS. 9 and 1 show a third embodiment of the present invention.
Description will be made based on 0. This embodiment corresponds to claims 4 and 21.

The image forming section of the LED array printer, the drive timing of the LED array head 3, and the image writing control section are the same as those in the first embodiment, and will not be described.

FIG. 9 shows a certain L in the present embodiment.
FIG. 1 shows the structure and light amount distribution of the ED element 16 in the vicinity of the light emitting section 20.
LED provided with a large number of such LED elements 16 in FIG.
FIG. 10B shows an example of the configuration of the array head 3, and FIG. 10B shows the light amount distribution of each LED element 16 in the sub-scanning direction, and FIG. 10C shows the light amount distribution of each LED element 16 in the main scanning direction (Th is the threshold level). FIG. 10D shows an example of image forming dots for each LED element 16. In the present embodiment, two separate electrodes 21d and 21e are provided on one light emitting unit 20 at both ends in the sub-scanning direction. Although not shown, the common electrode is provided below the light emitting unit 20 (under the light emitting unit 20). Since the current density in the vicinity of the individual electrodes 21d and 21e is high and the vicinity thereof emits strong light, the light quantity distribution in the sub-scanning direction has a shape with peaks on both sides, but the light quantity distribution in the main scanning direction is the same as in the conventional case. Two individual electrodes 21d, 21
If both e overlap the light emitting unit 20, there is no large deviation. Regarding the light quantity distribution in the sub-scanning direction, the individual electrodes 21 d and 2
Since control is possible by 1e, it is possible to suppress the deviation of the light quantity distribution, and as a result, it is possible to suppress the variation of the light quantity distribution among the LED elements 16. Further, the light amount distribution in the main scanning direction has a variation at the conventional level, but since the bias and variation in the sub-scanning direction are suppressed, no vertical streak occurs, and the distribution is shown in FIG. Thus, an image 22 having no white or black stripes is obtained.

The dots in FIG. 10 show the case where the gradation is expressed by the area gradation method (such as the error diffusion method) in a one-dot binary system. Since only one threshold level Th needs to be considered,
By simplifying the control system and setting the threshold level Th which is not affected by the drop in the central part of the light quantity distribution in the main scanning direction, a stable dot can be always formed.

A fourth embodiment of the present invention will be described with reference to FIGS. This embodiment corresponds to claims 5 and 21.

As described above, the image forming section of the LED array printer is the first embodiment (FIG. 1).
It is omitted because it is the same as.

In this embodiment, since four individual electrodes are provided for one LED element 16 in the present embodiment,
Double dot data is required, and if the basic configuration is used as it is, a shift register, a latch, and the like also need to be quadrupled. Therefore, when the image data is sent to the LED array driving unit 11, the image data is taken in from the outside at a frequency of １ ／ of the clock CLOCK of the shift register 12 in the LED array driving unit 11, so that the image data becomes dot 1 and dot 1. .., 1, dot 1, dot 1, dot 2, dot 2, dot 2, dot 2, dot 3,... Then, “1” of the image data
Only the dot (LED element 16) to which is transmitted is lit by the width of the strobe pulse STB by the four individual electrodes. Therefore, at the LED array drive timing shown in FIG. 3, DATA is transferred at a frequency of に 対 し て with respect to the clock CLOCK, but in the present embodiment, DATA is transferred at a frequency of ４. This is different from FIG.

The image writing control unit is the same as that of the first embodiment, and therefore its description is omitted. However, the FIFO memory 1 has a frequency of 1/4 of the clock CLOCK generated from the oscillator 18.
7 is different from the first embodiment in that image data is sequentially sent from the dot 1 to the LED array driving unit 11.

FIG. 11 shows the structure and light quantity distribution of a certain LED element 16 in the vicinity of the light emitting section 20 in this embodiment, and FIG. 12A shows an LE having a large number of such LED elements 16.
FIG. 12B shows an example of the configuration of the D array head 3 and its LEDs.
FIG. 12 (c) shows the light quantity distribution of each LED element 16 in the main scanning direction (Th indicates a threshold level), and FIG.
An example of image forming dots for each is shown. In the present embodiment, the four individual electrodes 21f, 21
g, 21i and 21j are divided into both ends in the main scanning direction and both ends in the sub-scanning direction. That is, the individual electrodes 21a and 21b shown in FIG. 5 are provided at both ends in the sub-scanning direction. Although not shown, the common electrode is provided below the light emitting unit 20 (under the light emitting unit 20). The current density in the vicinity of the individual electrodes 21f, 21g, 21i, and 21j is high, and the vicinity thereof emits light intensely. Therefore, the light amount distribution in the main scanning direction and the sub-scanning direction has a shape having irregularities. But,
Since the light quantity distribution in the main scanning direction and the sub-scanning direction can be controlled by the individual electrodes 21f, 21g, 21i, 21j, the bias can be suppressed as compared with the conventional case, and further, the first to the above-described first to fifth embodiments can be controlled. Individual electrodes 21f, 21g, 21 that can be individually controlled as compared with the third embodiment.
Since i and 21j are provided in the main scanning direction and the sub-scanning direction on the light emitting unit 20, the bias can be further suppressed. As a result, it is possible to suppress variations in the light amount distribution between the LED elements 16 in the main scanning direction and the sub-scanning direction, and FIG.
As shown in FIG. 2 (d), an image 22 without white or black stripes is obtained.

The dots in FIG. 12 show the case where the gradation is expressed by the area gradation method (error diffusion method or the like) in a one-dot binary system. Since only one threshold level Th needs to be considered,
By simplifying the control system and setting the threshold level Th which is not affected by the drop in the central part of the light quantity distribution in the main scanning direction, a stable dot can be always formed.

A fifth embodiment of the present invention will be described with reference to FIGS. This embodiment corresponds to claims 6 and 21.

As described above, the image forming section of the LED array printer is the first embodiment (FIG. 1).
It is omitted because it is the same as.

Regarding the drive timing of the LED array head 3, in this embodiment, since six individual electrodes are provided for one LED element 16, apparently six times as much dot data is required. Is used as it is, a shift register, a latch and the like are required six times. Therefore, in the present embodiment, the LED array driving unit 1
When the image data is sent to the pixel array 1, the image data is taken in from the outside at a frequency of 1/6 of the clock CLOCK of the shift register 12 in the LED array driving unit 11, so that the image data becomes dot 1, dot 1, dot 1, dot 1. 1, dot 1, dot 1, dot 2, dot 2, dot 2, dot 2, dot 2, dot 2, dot 3,... Then, only the dot (LED element 16) to which the image data “1” has been sent is lit by the width of the strobe pulse STB by the six individual electrodes. Therefore, at the LED array drive timing shown in FIG.
2, but in this embodiment, it is 1 /
6, and this point is different from FIG.

The image writing control unit is the same as that of the first embodiment, and therefore will not be described. However, the FIFO memory 1 has a frequency of 1/6 of the clock CLOCK generated from the oscillator 18.
7 is different from the first embodiment in that image data is sequentially sent from the dot 1 to the LED array driving unit 11.

FIG. 13 shows the structure and light quantity distribution of a certain LED element 16 in the vicinity of the light emitting portion 20 in this embodiment, and FIG. 14A shows an LE having a large number of such LED elements 16.
FIG. 14B shows an example of the configuration of the D array head 3 and its LEDs.
FIG. 14 (c) shows the light quantity distribution of each LED element 16 in the main scanning direction (Th indicates the threshold level), and FIG. 14 (d) shows the light quantity distribution of each LED element 16.
An example of image forming dots for each is shown. In the present embodiment, the individual electrodes 21f and 21 divided into six on one light emitting unit 20
g, 21i, 21j, 21k, and 21m are provided separately at both ends in the main scanning direction and at the center and both ends in the sub-scanning direction. That is, the individual electrodes 21a and 21 shown in FIG.
b and 21c are provided at both ends in the sub-scanning direction. Although not shown, the common electrode is provided below the light emitting unit 20 (under the light emitting unit 20). Individual electrodes 21f, 21
Since the current densities near g, 21i, 21j, 21k, and 21m are high and strong light is emitted in the vicinity thereof, the light amount distribution in the main scanning direction and the sub-scanning direction has a shape with irregularities. However, regarding the light amount distribution in the main scanning direction and the sub-scanning direction,
Each individual electrode 21f, 21g, 21i, 21j, 21
Since it is possible to control by k and 21 m, the bias can be suppressed as compared with the conventional one. Further, compared with the fourth embodiment, the number of the individually controllable two individual electrodes is increased, so that the bias is further increased. Can be suppressed. As a result, it is possible to suppress variations in the light amount distribution between the LED elements 16 in the main scanning direction and the sub-scanning direction, and to obtain an image 22 having no white stripes and no black stripes as shown in FIG.

The dots in FIG. 14 show the case where the gradation is expressed by the area gradation method (such as the error diffusion method) in a one-dot binary system. Since only one threshold level Th needs to be considered,
By simplifying the control system and setting the threshold level Th which is not affected by the drop in the central part of the light quantity distribution in the main scanning direction, a stable dot can be always formed.

A sixth embodiment of the present invention will be described with reference to FIGS. This embodiment relates to claim 7
And 8.

The image forming section of the LED array printer is the same as that of the first embodiment, and will not be described.

FIG. 15 shows a configuration example of an image writing control section in the LED array printer. The LED array drive section 11 has the same configuration as that of FIG. 2, but in this embodiment, it will be described later. The shift register 12 is reset by the eight-division synchronization signal / HSYNC because the eight-division synchronization signal / HSYNC (signal obtained by dividing the line synchronization signal / LSYNC into eight) for performing the light amount control by the lighting time control is used. ing.

The strobe pulse generator 19 is connected to the LED array driver 11 via the selector 31. The strobe pulse generator 19 is constituted by, for example, a counter, a comparator, and the like.
STB7 generates eight types of strobe pulses. These strobe pulses STB0 to STB7 are different from each other. When the width of strobe pulse STB0 is t, STB1 = 2t, STB2 = 4t, STB3 = 8.
t, STB4 = 16t, STB5 = 32t, STB6 =
The power relation is set to a power of 2 of 64t and STB7 = 128t. When the divided timings obtained by dividing one line into eight by the eight-divided synchronization signal / HSYNC are T0 to T7 in sequence, the strobe pulse STB0 at the timing T0, the strobe pulse STB1 at the timing T1,. A select operation is performed so that each pulse STB7 is output to the AND gate 14 of the LED array drive unit 11.

A multi-level conversion section 32 is connected to the LED array driving section 11 via a selector 33 as a separate system. The multi-level conversion unit 32 is constituted by, for example, an AND gate, and has 8-bit data b0 to b7.
Is output to the selector. The selector 33 outputs these 8-bit data b0 to b7 to the shift register 12 at the timing T0, b0, at the timing T1, b1,..., At the timing T7. On the input side of the multi-level conversion unit 32, a FIFO memory 34 and a correction data storage unit 35, which is a storage unit, are connected in parallel to take in one-bit binary image data for one line.

The FIFO memory 34 stores a line synchronization signal /
One line of image data is taken in from the outside by LSYNC. Then, the multi-level conversion unit 32 repeats the image data for one line by the eight-division synchronization signal / HSYNC.
Send to When sending to the multi-level conversion unit 32, in the present embodiment, two individual electrodes 21a, 21
b, and the lighting control can be performed individually for each. Therefore, the same image data is transmitted twice consecutively, that is, the read clock of the FIFO memory 34 is transferred to the data transfer unit 32 and subsequent data transfer units. It will be ク ロ ッ ク of the clock. Therefore, the amount of image data for one line is apparently doubled.

The correction data storage section 35 has, for example, a ROM configuration, and the light amount distribution of each LED element 16 in the LED array head 3 is set in advance for each of various measurement conditions by a measuring method described later. Correction data for obtaining a desired shape F is stored. In the image forming operation, when an image forming condition is designated by the image writing condition setting unit 36, the correction data corresponding to each LED element 16 is stored in the correction data storage unit 35 according to the designated image forming condition. It has a function of correction data reading means for reading and outputting the data to the multi-value conversion section 32. Further, the multi-value conversion unit 32, the selector 33, and the LE
The D array driver 11 uses the read correction data to read the individual electrodes 2 of each LED element 16 of the LED array head 3.
It functions as drive control means for controlling the energizing operation for 1a and 21b.

Here, acquisition of correction data written and stored in advance in the correction data storage unit 35 will be described. Acquisition of correction data is performed using an image writing device 37 and a light amount distribution correction data generation device 38 before shipment from the factory, as shown in FIG. This light amount distribution correction data generation device 3
8 is detachably connected to the multi-value conversion unit 32 of the image writing device 37 by an interface (not shown),
A controller 39 containing a microcomputer;
A light amount distribution measuring device 40 for measuring a light amount distribution when each LED element 16 is turned on and outputting the measurement result to a controller 39; and a measuring condition setting section 41 for setting measurement conditions by the light amount distribution measuring device 40. , Controller 3
9, a correction data setting unit 42 that outputs 8-bit correction data to the multi-value conversion unit 32 of the image writing device 37.
And a correction data storage device 43 for recording the correction data when the correction data is determined.

Here, the correction data of the light quantity distribution of each LED element 16 includes 8 bits (b0 to b) for changing the lighting time.
7) The timing T0 to T7 when the lighting in one line is divided into eight according to the eight-division synchronization signal / HSYNC.
, The least significant bit b0 is T0, b1 is T1,.
The most significant bit b7 is assigned to each of T7 and 8
Only the part of the bit where the bit is set (is 1)
The strobe pulse STBx at the timing Tx
It is the data to be turned on for the minute.

FIG. 17 shows dot 1 (No. 1) as an example.
The driving timing when the LED element 16) is turned on by the individual electrode 21a with the correction data '128' (= '10000000') is shown. Line synchronization signal / LS
By the time the YNC is output and the next line synchronization signal / LSYNC is output, this is divided into eight divided synchronization signals / HSYNC.
According to the timings T0 to T7 divided into eight by the NC, the strobe pulses STB0 to STB
TB7 is a strobe pulse generator 19 and a selector 31
Output from The lighting signal for the individual electrode 21a of the dot 1 is output every time the 8 division synchronization signal / HSYNC is performed, and the multi-value conversion unit 32 performs an AND process to set a bit indicating the correction data '128' b7. (= T
At the timing of 7), lighting is performed with a lighting width corresponding to the strobe pulse STB7. Assuming that the correction data is “127” (=
If it is “01111111”), lighting is performed at a lighting width corresponding to each of the strobe pulses STB0 to STB6 at the timing of b0 to b6 (= T0 to T6) when the bit is set.

Under such a premise, in order to make the light quantity distribution of each LED element 16 into a desired shape F, all of the N L
Regarding the ED element 16, each individual electrode 21a, 21b
The processing for acquiring the light amount distribution correction data in FIG.
This will be described with reference to the flowchart shown in FIG. Here, the measurement condition corresponding to the image forming condition such as the exposure condition is Cy (y
= 1 to Y: Y is arbitrary), and this condition is set as follows:
This is because the light amount distribution changes depending on the set light amount, and the dots formed thereby change. The measurement condition setting unit 41 sets the exposure condition in accordance with one of the exposure conditions at the time of actual image writing.

In this embodiment, each LED element 16 (N
The number of individual electrodes in the two (individual electrodes 21a, 21a)
1b). Therefore, the acquired correction data is N
× 2, and there are two correction data for one LED element 16, and there are apparently twice as many LED elements.

First, it is checked whether or not the prescribed light quantity distribution shape F has been set. When the prescribed shape F of the light amount distribution is set, it is checked whether the measurement condition Cy (y = 1) has been set. The measurement condition C1 is set by the measurement condition setting unit 41, and when various settings are completed, the dot 1 (LE of No. 1) is set.
In order to target the D element 16), n = 1 is set.
Next, the correction data M1ny (meaning the correction data by the individual electrode 21a for the n-th LED element 16 in the measurement condition y: here, the measurement condition is C1 and the first LED element 16), M2ny (n in the measurement condition y) Th LE
Means the correction data by the individual electrode 21b for the D element 16: Here, the measurement condition is C1 and the first LED element 1
6) is temporarily set to '128' (= '10000000'). However, there is no meaning to limit to this numerical value.
It is a numerical value in the range of '0' to '255' indicated by bit data, and uses a numerical value that is expected to be closest to a desired light quantity distribution shape F based on existing experimental data and the like.

The correction data M1ny and M2ny are set in the correction data setting section 42 and given to the multi-value conversion section 32, and the individual electrodes 21a and 21b provide the dot n, here dot 1 (the LED element 15 of No. 1). ) Is lit by the LED array drive unit 11. The lighting timing at this time is shown in FIG. At this time, the shape Ff of the light amount distribution of the dot n is measured by the light amount distribution measuring device 40, and the measurement result is sent to the controller 39. The controller 39 receiving the measurement result checks whether or not the shape Ff of the light amount distribution is almost equal to the shape F of the prescribed light amount distribution. If the correction data M1ny and M2ny are not equal to each other, the values of the correction data M1ny and M2ny are increased or decreased (for example, changed to '129' or '127'). However, the increase / decrease width is not limited to '1', and the correction data may be changed between M1ny and M2ny.) The shape Ff of the light amount distribution of the dot n to be lit according to the correction data is measured again, and this is measured. Shape Ff
Is substantially equal to the shape F of the specified light amount distribution. The determination that they are almost equal should be originally a determination of whether or not they are completely equal. However, due to the relationship between the number of bits of the correction data M1ny and M2ny, the measurement error of the shape Ff of the light amount distribution, and the like. Since it may not always be the same, it is determined that the data is normal when the data is within the allowable approximation range. The approximation range is determined in consideration of the number of bits of the correction data M1ny and M2ny, a measurement error of the shape Ff of the light amount distribution, a variation range of the light amount distribution that is allowable as a target image quality when an image is actually formed, and the like. You.

When the shape Ff of the measured light amount distribution becomes substantially equal to the prescribed shape F of the light amount distribution, the measuring condition Cy
Correction data M1n for dot n at (y = 1)
y and M2ny are stored in the correction data storage device 43. The correction data M1ny and M2ny at this time are the numerical values set in the correction data setting unit 42 at that time. After this,
Dot n, here dot 1 (No. 1 LED element 1
6) is turned off, and the next dot n, here dot 2 (No.
In order to target the two LED elements 16), n is incremented by +1. At this point, it is checked whether or not the number of new dots n does not exceed the total number N. If not, the above process is repeated for dot n. Thereby, for all the dots n (n = 1 to N) under the measurement condition Cy (y = 1), the correction data M1ny and M2ny for correcting the light quantity distribution shape Ff to the prescribed light quantity distribution shape F are corrected. The data is stored in the data storage device 43.

When this processing is completed, it is checked whether or not there are other measurement conditions Cy.
y (y = 2), Cy (y = 3),..., Cy (y = Y) are set in this order, and the correction data M described above is set for each measurement condition.
The processing for acquiring and storing 1ny and M2ny is repeated.

Therefore, after all the measurements are completed, the correction data storage device 43 stores the measurement condition correction data C1 M111 M211 M121 M221 M131 M231... M1N1 M2N1 C2 M112 M212 M122 M222 M132 M232. M12Y, M22Y, M13Y, M23Y... M1NY M2NY, correction data M1n for each individual electrode 21a, 21b at each dot in the form of using each measurement condition Cy as an address.
y and M2ny are stored. The correction data M stored in such a correction data storage device 43
1ny and M2ny are written into the correction data storage unit 35 of the LED array control unit 10 using a ROM writer or the like, and are used at the time of actual image writing.

The correction data M1n for each such condition
correction data storage section 35 in which y and M2ny are written
When the image is actually written by the LED array control unit 10 using, the desired image forming conditions are set by the image writing condition setting unit 36 and the image writing is started.
At this time, the correction data M1ny and M2ny corresponding to the condition Cy are read from the correction data storage unit 35 and output to the multi-value conversion unit 32.

For example, when writing an image of a certain line, if it is the measurement condition C2, M112, M212, M12
The correction data is read out as in 2, M222,. As an example, M112 = '128' (= '1,000,000)
0 '), M212 =' 145 '(=' 1001000)
1 '), the lighting drive timing at this time is as shown in FIG.
become that way.

That is, 1-bit binary image data is stored in the FIF
One line is input to the O memory 34, and the image data is repeatedly output from the FIFO memory 34 at the timing of the 8-divided synchronization signal / HSYNC. Multi-value converter 3
2, the same data is repeatedly input twice in succession, and further divided into eight divided synchronization signals / HSYN.
One line of image data is repeatedly input at the timing of C. On the other hand, from the correction data storage unit 35, each individual electrode 21 of each dot (each LED element 16) is read.
The 8-bit correction data for a and 21b is repeatedly output at the timing of the 8-divided synchronization signal / HSYNC, similarly to the image data. Then, the multi-value conversion unit 32 performs an AND operation on the image data and the correction data, and obtains the 8-bit data (b0
To b7) to the selector 33. Selector 33
In the timing T0, the least significant bit b0, in the timing T1, b1,..., And in the timing T7, the most significant bit b
7 is output. On the other hand, the strobe pulse generator 19 outputs strobe pulses STB0 to STB0 having different pulse widths.
STB7 is output to the selector 31, and the selector 31 outputs the strobe pulse STB0 at the timing T0, the strobe pulse STB1 at the timing T1,..., And the strobe pulse STB7 at the timing T7 to the AND gate 14 of the LED array drive unit 11. Select operation is performed. And b0-b7 and STB0
If the AND is taken at STB7 and both are active,
Lights at the timing of STB0 to STB7. As a result, the lighting is controlled at the timing as shown in FIG. 19, and the lighting is controlled so that the light amount distribution is made uniform in the shape F.

In the present embodiment, the correction data for one type of light amount distribution shape F is acquired. However, various types of light amount distribution shapes can be set so that various types of light amount distribution shapes can be set. Correction data for obtaining the shape Fx of various light amount distributions for each light amount distribution and each image forming condition may be obtained. In this case, the correction data storage unit 35 stores correction data for obtaining the shape Fx of various light amount distributions for each of various light amount distributions and each of various image forming conditions. FIG. 18 shows a process of acquiring correction data, but a process for determining whether or not there is another prescribed light amount distribution Fx is added.

In this embodiment, the LED element 16
Of the two individual electrodes 21 as in the first embodiment.
a, 21b (individual electrodes 21d, 21d of the third embodiment)
e), but is not limited thereto, and may be three or more as in the second, fourth, and fifth embodiments, and furthermore, the shape of the light amount distribution. Can be made uniform.

In this embodiment, assuming that the configuration of the LED array head 3 is as shown in FIGS. 5 and 6, in this case, the light amount distribution in the sub-scanning direction is
Depending on the mounting positions of a and 21b, each LED element 16 has a symmetrical shape with respect to the center of the light emitting section 20 in the sub-scanning direction, and it is difficult to make them all uniform. Therefore, in particular, the light amount distribution in the main scanning direction that affects the vertical stripes is corrected and made uniform, or the light amount distribution in the sub-scanning direction is two types (symmetry shape) of the prescribed k light amount distribution.
The setting is switched, and the light amount distribution is corrected by switching the setting to make the light amount distribution uniform. Alternatively, when measuring the light amount distribution, L
The light amount distribution in the sub-scanning direction is inverted with respect to the center of the light emitting unit 20 for each ED element 16 to make all of them uniform.

A seventh embodiment of the present invention will be described with reference to FIGS. This embodiment relates to claim 9
And 10 correspond to the invention.

The image forming unit of the LED array printer is the same as in the first embodiment, and will not be described.

The image writing control device 37, the drive timing of the LED array head 3, and the light amount distribution correction data generating device 38 are the same as those in the sixth embodiment, and therefore will not be described.

In the above-described sixth embodiment, the FIFO memory 34 fetches one line of image data from the outside in accordance with the line synchronization signal / LSYNC. Then, the image data for one line is repeatedly sent to the multi-level conversion unit 32 according to the eight-division synchronization signal / HSYNC. Multi-value converter 32
When sending the same image data twice, the LED device 16 is provided with two individual electrodes 21a and 21b, and the lighting can be individually controlled.
The read clock of the IFO memory 34 is set to the multi-level conversion unit 32
The subsequent data transfer clock is １ ／, and the image data amount for one line is apparently doubled.

On the other hand, in this embodiment, each LED
The two individual electrodes 21a and 21b in the element 16 are controlled by separate image data, respectively, so that the LED element 16
Is turned on, so that the image data needs to be twice as large as the LED element 16. Therefore, it is not necessary to reduce the read clock of the FIFO memory 34 to 1/2.

Each LED by each individual electrode 21a, 21b
A process of acquiring light amount distribution correction data for each of the individual electrodes 21a and 21b so that the light amount distribution of the element 16 has a desired shape F will be described with reference to a flowchart shown in FIG. Here, measurement conditions corresponding to image forming conditions such as exposure conditions are Cy (y = 1 to Y: Y is arbitrary),
This condition is set because the light amount distribution changes according to the set light amount, and the dots formed thereby change. Therefore, the measurement condition setting unit 41 matches one of the exposure conditions at the time of actual image writing. Is set by

In this embodiment, each LED element 16 (N
The number of individual electrodes in the two (individual electrodes 21a, 21a)
1b). Therefore, the acquired correction data is N
× 2, and there are two correction data for one LED element 16, and the image data is also twice the number of LED elements.

First, it is checked whether or not a prescribed light quantity distribution F has been set. When the prescribed shape F of the light amount distribution is set, it is checked whether the measurement condition Cy (y = 1) has been set. The measurement condition C1 is set by the measurement condition setting unit,
When various settings are completed, dot 1 (No. 1 LED element 1
Set n = 1 to target 6). Next, in order to target the individual electrode 1 (= individual electrode 21a), a
= 1. Then, the correction data Many (meaning the correction data by the individual electrode a for the n-th LED element in the measurement condition y: here, the measurement condition is C1, and the individual electrode 1 (= the individual electrode 21
a)) is temporarily set to '128' (= '10000000'). However, there is no point in limiting to this number,
It is a numerical value in the range of '0' to '255' indicated by 8-bit data, and a numerical value that is expected to be closest to a desired light quantity distribution shape F based on existing experimental data and the like is used.

The correction data Many is set in the correction data setting section 42, and is provided to the multi-value conversion section 32, where the individual electrode a, here the individual electrode 1 (= individual electrode 21a), generates the dot n, here the dot 1 (No. 1 LED element 16) is turned on by the LED array drive unit 11.
The lighting timing at this time is shown in FIG. At this time, the shape Ff of the light amount distribution of the dot n is measured by the light amount distribution measuring device 40, and the measurement result is sent to the controller 39. The controller 39 receiving the measurement result checks whether or not the shape Ff of the light amount distribution is almost equal to the shape F of the prescribed light amount distribution. If they are still not substantially equal, the correction data Many is set according to the magnitude relationship between the two.
Is increased or decreased (for example, '12
9) or “127”, but the increase / decrease width is not limited to “1”.) The shape Ff of the light amount distribution of the dot n to be lit according to the correction data is measured again, and this is changed to the light amount. The process is repeated until the distribution shape Ff becomes substantially equal to the prescribed light amount distribution shape F. Originally, the determination that they are almost equal should be made as to whether or not the two are completely equal. However, they are not necessarily equal due to the number of bits of the correction data Many and the measurement error of the shape Ff of the light amount distribution. Since it may not be possible, if the data is within an acceptable approximation range, it is determined that the data is normal. The approximation range is determined in consideration of the number of bits of the correction data Many, a measurement error of the shape Ff of the light amount distribution, a variation range of the light amount distribution that is allowable as a target image quality when an image is actually formed, and the like.

When the measured shape Ff of the light quantity distribution becomes substantially equal to the prescribed shape F of the light quantity distribution, the measurement condition Cy is used.
The correction data Many for the individual electrode a of the dot n at (y = 1) is stored in the correction data storage device 43.
The correction data Many at this time is a numerical value set in the correction data setting unit 42 at that time. Thereafter, the dot n, here, the dot 1 (the LED element 16 of No. 1) is turned off, and a is incremented by +1 in order to target the next individual electrode a, here, the individual electrode 2 (= individual electrode 21b). Increment. At this time, it is checked whether or not the total number of the individual electrodes a exceeds the total number A (the total number of the individual electrodes in one LED element 16).
Is repeated in the same manner. Thus, all the individual electrodes a (a = a) under the measurement condition Cy (y = 1)
With respect to 1 to A), the correction data Many for making the shape Ff of the light quantity distribution into the prescribed shape F of the light quantity distribution is stored in the correction data storage device 43. Total number A of individual electrodes a
Is exceeded, the next dot n, here dot 2 (N
In order to target the o.2 LED element 16), n is increased by +1.
Only increment. At this point, a new dot n
Check whether the total number does not exceed the total number N, and if not, repeat the above processing for dot n in the same manner. Thereby, for all the dots n (n = 1 to N) under the measurement condition Cy (y = 1), the correction data Many for setting the shape Ff of the light amount distribution by each individual electrode to the prescribed shape F of the light amount distribution. Is the correction data storage device 43
Is stored in

When this processing is completed, it is checked whether or not there are other measurement conditions Cy.
y (y = 2), Cy (y = 3),..., Cy (y = Y) are set in this order, and the correction data M described above is set for each measurement condition.
The process of acquiring and storing any is repeated.

Therefore, after all the measurements are completed, the correction data storage device 43 stores the measurement condition correction data C1 M111 M211 ... MA11 M121 M221 ... MA21 ... MA1 C2 M112 M212 ... Like M11Y M21Y... MA1Y M12Y M22Y... MA2Y... MANY, the correction data Many for each individual electrode in each dot is stored using each measurement condition Cy as an address. In the present embodiment, each LED element 16
Is provided with two individual electrodes 21a and 21b,
A = 2. The correction data Many stored in the correction data storage device 43 is written into the correction data storage unit 35 of the LED array control unit 10 using a ROM writer or the like, and is used at the time of actual image writing.

The correction data Man for each such condition
Using the correction data storage unit 35 in which y is written,
When actually writing an image by the LED array control unit 10, a desired image forming condition is set by the image writing condition setting unit 36, and writing of the image is started. Is read out of the correction data Many corresponding to the condition Cy and output to the multi-value conversion unit 32.

For example, when writing an image of a certain line, if the measurement condition C2 is two (A = 2) (= individual electrodes 21a, 21b), M112, M212,
The correction data is read out as in M122, M222,.
As an example, M112 = '128' (= '10000)
000 '), M212 =' 145 '(=' 1001000)
1 '), the lighting drive timing at this time is as shown in FIG.
become that way.

That is, 1-bit binary image data is
One line is input to the O memory 34, and the image data is repeatedly output from the FIFO memory 34 at the timing of the 8-divided synchronization signal / HSYNC. The image data for one line is twice the number N of LED elements. On the other hand, from the correction data storage unit 35, each dot (each LED element 1
6), the 8-bit correction data for each of the individual electrodes 21a and 21b is converted into an 8-divided synchronization signal / HSYNC similarly to the image data.
Is output repeatedly at the timing of. Then, the multi-value conversion section 32 performs an AND operation on the image data and the correction data, and
The data is sent to the selector as bit data (b0 to b7). The selector 33 outputs the least significant bit b0 at the timing T0, b1 at the timing T1,..., And the most significant bit b7 at the timing T7. On the other hand, the strobe pulse generator 19 outputs strobe pulses STB0 to STB7 having different pulse widths to the selector 31,
In the selector 31, the strobe pulse STB0 at the timing T0 and the strobe pulse S at the timing T1.
.., At timing T7, the strobe pulse ST
A select operation is performed so as to output B7 to the AND gate 14 of the LED array drive unit 11. And b0
AND is performed between b7 and STB0 to STB7, and if both are active, the light is turned on at the timing of STB0 to STB7. As a result, the lighting is controlled at the timing shown in FIG. 21 and the lighting is controlled so as to be uniformed in the shape F of the light amount distribution.

FIG. 22 shows the structure of the light emitting section 20 of the LED element 16, the light amount distribution, and the dots formed. In the case of the present embodiment, two individual electrodes 21a and 21b are provided for one LED element 16 (light emitting section 20), and lighting control is performed using different image data and correction data, respectively.
With the structure as shown in FIG. 22, each individual electrode 21
The light quantity distribution in the main scanning direction due to a and 21b becomes symmetrical in the main scanning direction with respect to the center of the light emitting unit 20 as shown in the figure. In addition, the light amount distribution in the sub-scanning direction is symmetrical with respect to the center of the light emitting unit 20 in the sub-scanning direction for each LED element 16 depending on the mounting position of the individual electrodes 21a and 21b.

Therefore, as for the light amount distribution in the main scanning direction, two types (symmetrical shapes) of the prescribed light amount distribution are set, and the light amount distribution is corrected by switching the shapes, thereby making each light amount distribution uniform. Alternatively, when measuring the shape of the light amount distribution, the light amount distribution in the main scanning direction is inverted with respect to the center of the light emitting unit 20 for each of the individual electrodes 21a and 21b, so that all are uniformed.

Regarding the light amount distribution in the sub-scanning direction, the light amount distribution in the main scanning direction which particularly affects the vertical streak is corrected, and the light amount distribution in the sub-scanning direction is ignored or the light amount distribution in the sub-scanning direction is specified. Are set in two types (symmetrical shapes), and by switching between them, the light amount distribution is corrected and made uniform. Alternatively, when measuring the shape of the light amount distribution, the light amount distribution in the sub-scanning direction is inverted for each LED element 16 with respect to the center of the light emitting unit 20 to make all of them uniform.

As a result, two uniform dots are formed for one LED element 16 (light emitting section 20), and all dots in the LED array head 3 are uniform. In addition, the resolution is apparently doubled.

By the way, if the individual electrodes 21a and 21b are turned on and off with the same data, each LED element 16
Is corrected to the light amount distribution shown by the dotted line in FIG. 22, which is the same as in the sixth embodiment.

In this embodiment, the correction data for one type of light quantity distribution shape F is obtained.
In order to make various settings for the shape of the light amount distribution, correction data for obtaining the shape Fx of the various light amount distributions may be obtained for each of various light amount distributions and for each of various image forming conditions. In this case, the correction data storage unit 35 stores various light amount distributions F for each of various light amount distributions and for various image forming conditions.
Correction data for x is stored. FIG. 20 shows the process of acquiring the correction data, but a process for determining whether or not there is another shape Fx of the specified light amount distribution is added.

Further, in the present embodiment, the LED element 16
Of the two individual electrodes 21 as in the first embodiment.
a, 21b (individual electrodes 21d, 21d of the third embodiment)
e), but is not limited thereto, and may be three or more as in the second, fourth, and fifth embodiments, and furthermore, the shape of the light amount distribution. Can be made uniform.

An eighth embodiment of the present invention will be described with reference to FIGS. This embodiment relates to claim 1
This corresponds to the inventions described in 1 and 12.

The image forming unit of the LED array printer is the same as in the first embodiment, and will not be described.

FIG. 23 shows an image writing control unit according to the present embodiment, which differs from the sixth embodiment shown in FIG.
The difference is that the image writing condition setting unit 36 is not provided.
This is because, in the present embodiment, the lighting control is performed so as to equalize the light amount of each LED element 16 to the specified light amount. Therefore, since there is no correction data for each image writing condition, the image writing condition setting unit 36 is particularly required. It is not provided.

The drive timing of the LED array head 3 is the same as in the sixth embodiment, and a description thereof will be omitted.

The acquisition of correction data written and stored in advance in the correction data storage unit 35 will be described. The acquisition of the correction data is executed before shipment from the factory, using the image writing device 37 and the light quantity correction data generation device 45 as shown in FIG. The light amount correction data generation device 45 is detachably connected to the multi-value conversion unit 32 of the image writing device 37 by an interface (not shown), and includes a controller 46 having a built-in microcomputer and each LED element 16.
The 8-bit correction data is supplied to the multi-value conversion unit 32 of the image writing device 37 under the control of the controller 46 by measuring the amount of light when is turned on and outputting the measurement result to the controller 46. It is composed of a correction data setting section 48 for outputting, and a correction data storage device 49 for recording the correction data when the correction data is determined.

FIG. 25 shows a process of acquiring light quantity correction data for each of the individual electrodes 21a and 21b for all N LED elements 16 in order to set the light quantity of each LED element 16 to a desired value P. This will be described with reference to a flowchart.

In this embodiment, each LED element 16 (N
The number of individual electrodes in the two (individual electrodes 21a, 21a)
1b). Therefore, the acquired correction data is N
× 2, and there are two correction data for one LED element 16, and there are apparently twice as many LED elements.

First, it is checked whether a prescribed light amount value P has been set. When the prescribed light amount value P is set, n = 1 is set to target the dot 1 (the LED element 16 of No. 1). Next, correction data M1n (meaning correction data by the individual electrode 1 (= individual electrode 21a) for the n-th LED element 16: here is the first LED element), M2n (individual for the n-th LED element 16) The correction data by the electrode 2 (= individual electrode 21b: here is the first LED element) is temporarily assumed to be “128” (= “1000”).
0000 '). However, there is no meaning limited to this numerical value, and "0" to "2" represented by 8-bit data
A numerical value within the range of 55 ', which is expected to be closest to a desired light amount value P based on existing experimental data or the like is used.

The correction data M1n and M2n are set in the correction data setting section 48 and provided to the multi-value conversion section 32.
The dot n, here the dot 1 (No. 1 LED element), is set to L by the individual electrodes 1 and 2 (individual electrodes 21a and 21b).
It is turned on by the ED array drive unit 11. The lighting timing at this time is shown in FIG. Dot n at this time
Is measured by the light amount measuring device 47 and the measurement result is sent to the controller 46. The controller 46 receiving the measurement result checks whether or not the light amount value Pp is almost equal to the specified light amount value P. If they are still not substantially equal, the values of the correction data M1n and M2n are increased or decreased (for example, changed to '129' or changed to '127') according to the magnitude relation between them. However, the increment / decrement width is not limited to '1', and M1n
And M2n, the correction data may be changed), the light amount value Pp of the dot n which is lit according to the correction data is measured again, and this is repeated until the light amount value Pp becomes almost equal to the specified light amount value P. The determination that they are almost equal should be a determination as to whether or not both are completely equal. However, the number of bits of the correction data M1n and M2n and the light amount value P
Since it is possible that the values may not always be equal due to the relationship of the measurement error of p, etc., when the data is within the allowable approximation range, it is determined that the data is normal.
The approximate range is the number of bits of the correction data M1n and M2n,
The light amount value Pp is determined in consideration of a measurement error of the light amount value Pp, a variation range of the light amount allowable as a target image quality when an image is actually formed, and the like.

The measured light quantity value Pp is equal to the specified light quantity value P.
Is substantially equal to the correction data M1n, M2n for the dot n is stored in the correction data storage device 49. The correction data M1n and M2n at this time are numerical values set in the correction data setting unit 48 at that time. Thereafter, the dot n, here, the dot 1 (No. 1 LED element) is turned off, and the next dot n, here, the dot 2 (No. 2 LED element)
N) is incremented by +1 in order to target (element). At this point, it is checked whether or not the number of new dots n does not exceed the total number N. If not, the above process is repeated for dot n. This allows
For all the dots n (n = 1 to N), correction data M1n for setting the light amount value Pp to the specified light amount value P,
M2n is stored in the correction data storage device 49.

Therefore, after all the measurements are completed, the correction data storage device 49 stores the LED No. of the LED element 16 such as LED No. correction data 1 M11 M21 2 M12 M22... N M1N M2N. , The correction data M1n and M2n for each individual electrode 21a and 21b in each dot are stored. The correction data M1n and M2n stored in the correction data storage device 49 are written into the correction data storage unit 35 of the LED array control unit 10 using a ROM writer or the like, and are used at the time of actual image writing.

The correction data storage unit 3 into which such correction data M1n and M2n for each LED element 16 are written.
5, when the LED array control unit 10 actually writes an image, the correction data storage unit 35 stores
The correction data M1n and M2n corresponding to the D element 16 are read and output to the multi-level conversion unit 32.

In this embodiment, the correction data for one kind of light amount value P is obtained. However, the correction data is obtained for each light amount so that various settings can be made for the light amount. It may be. In this case, the correction data storage unit 35 stores various light amount values Px for each of various light amounts.
Is stored. FIG.
The process of acquiring the correction data is shown in FIG. 5, but a process for determining whether or not there is another specified light amount value Px is added. An image writing condition setting unit is added to the LED array driving unit 10 of FIG. 23. When actually writing an image, a desired image forming condition (light amount) is set from the image writing condition setting unit 36. The correction data is read out from the correction data storage unit 35 and the multi-value conversion unit 32 is set.
Output to

Further, in the present embodiment, the LED element 16
Of the two individual electrodes 21 as in the first embodiment.
a, 21b (individual electrodes 21d, 21d of the third embodiment)
e) is provided, but the invention is not limited to this, and three or more may be provided as in the second, fourth, and fifth embodiments.

The ninth embodiment of the present invention will be described with reference to FIG. This embodiment corresponds to claims 13 and 14.

The image forming unit of the LED array printer is the same as in the first embodiment, and will not be described.

The drive timing of the image writing control unit 10 and the LED array head 3 and the light quantity correction data generation device 45 are the same as those in the eighth embodiment, and therefore will not be described.

In the eighth embodiment, the FIFO memory 3
Reference numeral 4 captures one line of image data from the outside in response to the line synchronization signal / LSYNC. Then, the image data for one line is repeatedly sent to the multi-level conversion unit 32 according to the eight-division synchronization signal / HSYNC. When sending to the multi-value conversion unit 32, two individual electrodes 21 for each LED element 16 are used.
a and 21b, each of which can be individually turned on and off, so that the same image data is sent twice consecutively, that is,
The read clock of the O memory 34 is set to の of the data transfer clock after the multi-level converter 32, and the amount of image data for one line is apparently doubled. However, in the present embodiment, the two individual electrodes 21a and 21b in each LED element 16 are controlled by separate image data to turn on the LED element 16, so that the image data needs to be twice as large as the LED element 16. become. Therefore,
It is not necessary to reduce the read clock of the FIFO memory 34 to 1/2.

Each LED by each individual electrode 21a, 21b
A process of acquiring light amount correction data for each of the individual electrodes 21a and 21b in order to set the light amount of the element 16 to a desired value P will be described with reference to a flowchart shown in FIG.

In this embodiment, each LED element 16 (N
The number of individual electrodes in the two (individual electrodes 21a, 21a)
1b). Therefore, the acquired correction data is N
× 2, and there are two correction data for one LED element 16, and the image data is also twice the number of LED elements.

First, it is checked whether or not a prescribed light amount value P has been set. When a prescribed light amount value P is set, n = n in order to target dot 1 (the LED element of No. 1).
Set to 1. Next, a = 1 is set in order to target the individual electrode 1 (= individual electrode 21a). Then, the correction data Man (meaning the correction data by the individual electrode a for the n-th LED element 16: here, the individual electrode 1 (= individual electrode 21a) is temporarily set to '12 by the first LED element.
8 '(=' 10000000 '). However, there is no meaning to limit to this numerical value, and it is a numerical value in the range of '0' to '255' indicated by 8-bit data, and it is most necessary to set a desired light amount value P based on existing experimental data and the like. Use a value that is expected to be close.

The correction data Man is set in the correction data setting section 48, and is provided to the multi-value conversion section 32. The individual electrode a, here the individual electrode 1 (= individual electrode 21a), causes the dot n, here the dot 1 (No. 1 LED element) is turned on by the LED array drive unit. The lighting timing at this time is shown in FIG. At this time, the light amount value Pp of the dot n is measured by the light amount measuring device 47,
The measurement result is sent to the controller 46. The controller 46 receiving the measurement result checks whether or not the light amount value Pp is almost equal to the specified light amount value P. If they are still not almost equal,
The value of the correction data Man is increased or decreased (for example, it is changed to '129' or '127', but the increase / decrease width is not limited to '1'), and the lighting is performed according to the correction data. The light quantity value Pp of the dot n is measured again, and this is repeated until the light quantity value Pp becomes almost equal to the specified light quantity value P. The determination that they are almost equal to each other should originally be a determination as to whether or not both are completely equal. However, the number of bits of the correction data Man and the light amount value P
Since it is possible that the values may not always be equal due to the relationship of the measurement error of p, etc., when the data is within the allowable approximation range, it is determined that the data is normal.
The approximate range is determined in consideration of the number of bits of the correction data Man, the measurement error of the light amount value Pp, the variation range of the light amount that is allowable as the target image quality when an image is actually formed, and the like.

The measured light quantity value Pp is equal to the specified light quantity value P.
Is substantially equal to the correction data Man for the individual electrode a of the dot n is stored in the correction data storage device 49. The correction data Man at this time is a numerical value set in the correction data setting unit 48 at that time. Thereafter, the dot n, here, the dot 1 (the LED element 16 of No. 1) is turned off, and a is incremented by +1 in order to target the next individual electrode a, here, the individual electrode 2 (= individual electrode 21b). Increment. At this time, it is checked whether the total number of individual electrodes a does not exceed the total number A (the total number of individual electrodes in one LED element), and if not, the above process is repeated for the individual electrodes a. Thus, the light amount value P for all the individual electrodes a (a = 1 to A)
Correction data Man for setting p to the value P of the specified light amount is stored in the correction data storage device 49. If the number of individual electrodes a exceeds the total number A, the next dot n, here dot 2
In order to make the (No. 2 LED element 16) a target, n is incremented by +1. At this point, it is checked whether or not the number of new dots n does not exceed the total number N. If not, the above process is repeated for dot n. Thus, the correction data Man for storing the light amount value Pp of each individual electrode to the specified light amount value P is stored in the correction data storage device 49 for all the dots n (n = 1 to N).

Therefore, after all the measurements are completed, the correction data storage device 49 stores the LED No. correction data 1 M11 M21... MA1 2 M12 M22... MA2... N M1N M2N. No. Is used as an address, and the correction data Man for each individual electrode 21a, 21b in each dot is stored. The correction data Man stored in such a correction data storage device 49
Is written into the correction data storage unit 35 of the LED array control unit 10 using a ROM writer or the like, and is used at the time of actual image writing.

When an image is actually written by the LED array control unit 10 using the correction data storage unit 35 in which the correction data Man for each of the LED elements 16 and the individual electrodes 21a and 21b is written. Indicates that each individual electrode 21 of each LED element 16 is
The correction data Man corresponding to a and 21b is read and output to the multi-level conversion unit 32.

As a result, two uniform dots are formed for one LED element 16 (light emitting portion 20).
All dots in the LED array head 3 are made uniform. In addition, the resolution is apparently doubled.

In this embodiment, the correction data for one kind of light amount value P is obtained. However, the correction data is obtained for each light amount so that various settings can be made for the light amount. It may be. In this case, the correction data storage unit 35 stores various light amount values Px for each of various light amounts.
Is stored. FIG.
The processing for acquiring the correction data is shown in FIG. 6, and processing for determining whether or not there is another value Px of the specified light amount is added. An image writing condition setting unit is added to the LED array control unit 10 of FIG. 23, and when actually writing an image, a desired image forming condition (light amount) is set from the image writing condition setting unit 36. Then, the corresponding correction data is read out from the correction data storage unit 35 and the multi-value conversion unit 32
Output to

In this embodiment, the LED element 16
Of the two individual electrodes 21 as in the first embodiment.
a, 21b (individual electrodes 21d, 21d of the third embodiment)
e) is provided, but the invention is not limited to this, and three or more may be provided as in the second, fourth, and fifth embodiments.

A tenth embodiment of the present invention will be described with reference to FIGS. This embodiment relates to claim 15
And 16.

The image forming unit of the LED array printer is the same as that of the first embodiment, and will not be described.

The drive timings of the image writing control unit 10 and the LED array head 3 are the same as in the sixth embodiment, and will not be described.

The acquisition of the correction data written and stored in advance in the correction data storage unit 35 will be described. The acquisition of the correction data is executed before shipment from the factory using the image writing device 37 and the beam spot diameter correction data generation device 51 as shown in FIG. The beam spot diameter correction data generation device 51 is detachably connected to the multi-value conversion section 32 of the image writing device 37 by an interface (not shown), and includes a controller 52 including a microcomputer, A beam spot diameter measuring device 53 for measuring a beam spot diameter when the lamp 16 is turned on and outputting the measurement result to a controller 52; a measurement condition setting unit 54 for setting measurement conditions by the beam spot diameter measuring device 53; A correction data setting unit 55 that outputs 8-bit correction data to the multi-value conversion unit 32 of the image writing device 37 under the control of the controller 52, and correction data that records the correction data when the correction data is determined And a storage device 56.

In order to set the beam spot diameter of each LED element 16 to a desired diameter D, a process of acquiring beam spot diameter correction data for each of the individual electrodes 21a and 21b for all N LED elements 16 is performed. This will be described with reference to the flowchart shown in FIG. Here, measurement conditions corresponding to image forming conditions such as exposure conditions are Cy (y = 1 to 1).
Y: Y is arbitrary), and this condition is set because the beam spot diameter changes depending on the set light amount and the threshold level, and the dots formed thereby change. It is set by the measurement condition setting unit 54 in accordance with one of the conditions.

In this embodiment, each LED element 16 (N
The number of individual electrodes in the two (individual electrodes 21a, 21a)
1b). Therefore, the acquired correction data is N
× 2, and there are two correction data for one LED element 16, and there are apparently twice as many LED elements.

First, it is checked whether a specified spot diameter D has been set. When the specified spot diameter D is set,
It is checked whether the measurement condition Cy (y = 1) has been set. The measurement condition C1 is set by the measurement condition setting unit 54, and when various settings are completed, n = 1 is set to target the dot 1 (the LED element 16 of No. 1). Next, the correction data M1ny (meaning the correction data by the individual electrode 1 (= individual electrode 21a) for the n-th LED element in the measurement condition y: here, the measurement condition is C1 and the first LED element 16), M2ny (Individual electrode 2 for n-th LED element under measurement condition y (= individual electrode 21
b) means the correction data according to b): In this case, the measurement condition is C1 and the first LED element is “128” (= “1”).
00000000 '). However, there is no meaning limited to this numerical value, and "0" indicated by 8-bit data is used.
A value within the range of '255', which is expected to be closest to the desired spot diameter D based on existing experimental data and the like.

The correction data M1ny and M2ny are set in the correction data setting section 55 and provided to the multi-value conversion section 32, where the individual electrodes 1 and 2 (= individual electrodes 21a and 21b) perform dot n, here dot 1 (No. 1 LED element 16) is turned on by the LED array drive unit 11. The lighting timing at this time is shown in FIG. At this time, the spot diameter Dd of the dot n is measured by the beam spot diameter measuring device 53, and the measurement result is sent to the controller 52. The controller 52 receiving the measurement result checks whether or not the spot diameter Dd is almost equal to the specified spot diameter D. If the values are still not substantially equal, the values of the correction data M1ny and M2ny are increased or decreased (for example, changed to '129' or '127') according to the magnitude relation between them. However, the increase / decrease range is not limited to “1”, and the correction data may be changed between M1ny and M2ny.)
The spot diameter Dd is measured again, and the spot diameter Dd is measured.
Is almost equal to the specified spot diameter D. The determination that they are almost equal should originally be a determination as to whether or not they are completely equal, but they are not necessarily equal due to the relationship between the number of bits of the correction data M1ny, M2ny, the measurement error of the spot diameter Dd, and the like. Since it may not be possible, if the data is within an acceptable approximation range, it is determined that the data is normal. The approximate range is determined in consideration of the number of bits of the correction data M1ny and M2ny, a measurement error of the spot diameter Dd, a variation range of the spot diameter that is allowable as a target image quality when an image is actually formed, and the like.

When the measured spot diameter Dd becomes substantially equal to the specified spot diameter D, the measurement condition Cy (y = 1)
Correction data M1ny, M2ny for dot n at
Is stored in the correction data storage device 56. The correction data M1ny and M2ny at this time are stored in the correction data setting unit 5 at that time.
This is the numerical value set to 5. Thereafter, the dot n, here, the dot 1 (the LED element 16 of No. 1) is turned off,
In order to target the next dot n, here, dot 2 (the LED element 16 of No. 2), n is incremented by +1. At this point, it is checked whether or not the number of new dots n does not exceed the total number N. If not, the above process is repeated for dot n. This allows
All the dots n (n = n) in the measurement condition Cy (y = 1)
1 to N), the correction data M1ny and M2ny for setting the spot diameter Dd to the specified spot diameter D are stored in the correction data storage device 56.

When this processing is completed, it is checked whether or not there are other measurement conditions Cy.
y (y = 2), Cy (y = 3),..., Cy (y = Y) are set in this order, and the correction data M described above is set for each measurement condition.
The processing for acquiring and storing 1ny and M2ny is repeated.

Therefore, after all the measurements are completed, the correction data storage device 56 stores the measurement condition correction data C1 M111 M211 M121 M221 M131 M231... M1N1 M2N1 C2 M112 M212 M122 M222 M132 M232. M12Y, M22Y, M13Y, M23Y... M1NY M2NY, correction data M1n for each individual electrode 21a, 21b at each dot in the form of using each measurement condition Cy as an address.
y and M2ny are stored. The correction data M stored in such a correction data storage device 56
1ny and M2ny are written into the correction data storage unit 35 of the LED array control unit 10 using a ROM writer or the like, and are used at the time of actual image writing.

The correction data M1n for each such condition
correction data storage section 35 in which y and M2ny are written
When the image is actually written by the LED array control unit 10 using, the desired image forming conditions are set by the image writing condition setting unit 36 and the image writing is started.
At this time, the correction data M1ny and M2ny corresponding to the condition Cy are read from the correction data storage unit 35 and output to the multi-value conversion unit 32.

In this embodiment, one kind of spot diameter D
However, the correction data for obtaining various spot diameters Dx for various spot diameters and various image forming conditions may be obtained so that various settings can be made for the spot diameter. It may be. In this case, the correction data storage unit 35 stores correction data for setting various spot diameters Dx for various spot diameters and various image forming conditions. FIG. 28 shows a process for acquiring correction data, but a process for determining whether or not there is another spot diameter Dx is added.

In this embodiment, the LED element 16
Of the two individual electrodes 21 as in the first embodiment.
a, 21b (individual electrodes 21d, 21d of the third embodiment)
e) is provided, but the invention is not limited to this, and three or more may be provided as in the second, fourth, and fifth embodiments.

The eleventh embodiment of the present invention will be described with reference to FIG. This embodiment relates to claims 17 and 18.
This corresponds to the described invention.

The image forming unit of the LED array printer is the same as in the first embodiment, and will not be described.

The LED array controller 10, the driving timing of the LED array head 3, the image writing device 37, and the beam spot diameter correction data generating device 51 are the same as those in the tenth embodiment, and will not be described.

In the tenth embodiment, the FIFO memory 34 fetches one line of image data from the outside in accordance with the line synchronization signal / LSYNC. Then, the image data for one line is repeatedly sent to the multi-level conversion unit 32 according to the eight-division synchronization signal / HSYNC. Multi-value converter 32
When sending the same image data twice, the LED device 16 is provided with two individual electrodes 21a and 21b, and the lighting can be individually controlled.
The read clock of the IFO memory 34 is set to the multi-level conversion unit 32
Since the subsequent data transfer clock is １ ／, the amount of image data for one line is apparently doubled. However, in the present embodiment, 2
Since the individual electrodes 21a and 21b are controlled by separate image data to turn on the LED elements 16,
Image data is required twice as much as the LED element 16. Therefore, it is not necessary to reduce the read clock of the FIFO memory 34 to 1/2.

Each LED by each individual electrode 21a, 21b
A process of acquiring beam spot diameter correction data for each of the individual electrodes 21a and 21b in order to set the beam spot diameter of the element 16 to a desired diameter D will be described with reference to a flowchart shown in FIG. Here, measurement conditions corresponding to image forming conditions such as exposure conditions are Cy (y = 1 to Y:
Y is arbitrary), and this condition is set by the set light amount,
The beam spot diameter changes depending on the threshold level,
This is because the dots formed thereby change, and are set by the measurement condition setting unit 54 in accordance with one of the exposure conditions at the time of actual image writing.

In this embodiment, each LED element 16 (N
The number of individual electrodes in the two (individual electrodes 21a, 21a)
1b). Therefore, the acquired correction data is N
× 2, and there are two correction data for one LED element 16, and the image data is also twice the number of LED elements.

First, it is checked whether a specified spot diameter D has been set. When the specified spot diameter D is set,
It is checked whether the measurement condition Cy (y = 1) has been set. The measurement condition C1 is set by the measurement condition setting unit 54, and when various settings are completed, n = 1 is set to target the dot 1 (the LED element 16 of No. 1). Next, a = 1 is set in order to target the individual electrode 1 (= individual electrode 21a). Then, the correction data Many
(Meaning the correction data by the individual electrode a for the n-th LED element in the measurement condition y: here, the measurement condition is C
Assuming that the individual electrode 1 (= individual electrode 21a) of the first LED element 16 is “128” (= “1,000,000”).
0 '). However, there is no meaning limited to this numerical value, and "0" to "255" represented by 8-bit data
And a numerical value expected to be closest to a desired spot diameter D based on existing experimental data and the like.

The correction data Many is set in the correction data setting section 55, and is provided to the multi-value conversion section 32, where the individual electrode a, here the individual electrode 1 (= individual electrode 21a), is used for the dot n, here the dot. 1 (No. 1 LED element 16) is turned on by the LED array drive unit 11.
The lighting timing at this time is shown in FIG. At this time, the spot diameter Dd of the dot n is measured by the beam spot diameter measuring device 53, and the measurement result is sent to the controller 52. The controller 52 receiving the measurement result checks whether or not the spot diameter Dd is almost equal to the specified spot diameter D. If the values are still not substantially equal, the value of the correction data Many is increased or decreased (for example, changed to '129' or '127') according to the magnitude relationship between the two. Increase / decrease range is '1'
Dot n), the dot n which is lit according to the correction data
The spot diameter Dd is measured again, and the spot diameter Dd is measured.
Is almost equal to the specified spot diameter D. The determination that they are almost equal should originally be a determination as to whether or not both are completely equal. However, they should not always be equal due to the number of bits of the correction data Many and the measurement error of the spot diameter Dd. Is also possible,
If the data is within an acceptable approximation range, it is determined that the data is normal. This approximation range is
The number of bits is determined in consideration of the number of bits of the correction data Many, the measurement error of the spot diameter Dd, the variation range of the spot diameter that is allowable as the target image quality when an image is actually formed, and the like.

When the measured spot diameter Dd is substantially equal to the specified spot diameter D, the measurement condition Cy (y = 1)
Data Ma for the individual electrode a of the dot n at
ny is stored in the correction data storage device 56. The correction data Many at this time is a numerical value set in the correction data setting unit 55 at that time. Thereafter, the dot n, here, the dot 1 (the LED element of No. 1) is turned off, and a is incremented by +1 to target the next individual electrode a, here, the individual electrode 2 (= individual electrode 21b). I do. At this time, it is checked whether the total number of individual electrodes a does not exceed the total number A (the total number of individual electrodes in one LED element), and if not, the above process is repeated for the individual electrodes a. Thereby, the measurement condition Cy (y = y
The correction data Many for making the spot diameter Dd the specified spot diameter D for all the individual electrodes a (a = 1 to A) in 1) is stored in the correction data storage device 56. If the number of individual electrodes a exceeds the total number A, n is incremented by +1 in order to target the next dot n, here, dot 2 (the LED element of No. 2). At this point, it is checked whether or not the number of new dots n does not exceed the total number N. If not, the above process is repeated for dot n. Thereby, the measurement condition Cy is obtained.
For all dots n (n = 1 to N) in (y = 1), the correction data Many for setting the spot diameter Dd of each individual electrode to the specified spot diameter D is stored in the correction data storage device 56.

When this processing is completed, it is checked whether or not there are other measurement conditions Cy.
y (y = 2), Cy (y = 3),..., Cy (y = Y) are set in this order, and the correction data M described above is set for each measurement condition.
The process of acquiring and storing any is repeated.

Therefore, after all the measurements have been completed, the correction data storage device 56 stores the measurement condition correction data C1 M111 M211... MA11 M121 M221... MA21 ... MA1 C2 M112 M212. M11Y M21Y... MA1Y M12Y M22Y... MA2Y... MANY as in the case of each measurement condition Cy as an address, the correction data Man for each individual electrode 21a, 21b in each dot.
This means that y is stored. In this embodiment, each L
Since the ED element 16 has the two individual electrodes 21a and 21b, A = 2. The correction data Many stored in the correction data storage device 56 is stored in the ROM.
The data is written into the correction data storage unit 35 of the LED array control unit 10 using a writer or the like, and is used at the time of actual image writing.

The correction data Man for each such condition
Using the correction data storage unit 35 in which y is written,
When actually writing an image by the LED array control unit 10, a desired image forming condition is set by the image writing condition setting unit 36, and writing of the image is started. Is read out of the correction data Many corresponding to the condition Cy and output to the multi-value conversion unit 32.

As a result, one LED element 16
Two uniform dots are formed on the (light emitting unit 20), and all dots in the LED array head 3 are uniform. In addition, the resolution is apparently doubled.

In this embodiment, one kind of spot diameter D
However, the correction data for obtaining various spot diameters Dx for various spot diameters and various image forming conditions may be obtained so that various settings can be made for the spot diameter. It may be. In this case, the correction data storage unit 35 stores correction data for setting various spot diameters Dx for various spot diameters and various image forming conditions. FIG. 29 shows a process of acquiring correction data, but a process for determining whether or not there is another specified spot diameter Dx is added.

Also, in the present embodiment, the LED element 16
Of the two individual electrodes 21 as in the first embodiment.
a, 21b (individual electrodes 21d, 21d of the third embodiment)
e), but the invention is not limited to this. The number of spots may be three or more as in the second, fourth, and fifth embodiments, and the spot diameter may be uniform. Can be

A twelfth embodiment of the present invention will be described with reference to FIGS. This embodiment relates to claim 1
This corresponds to the inventions described in 9 and 20.

The image forming unit of the LED array printer is the same as in the first embodiment, and will not be described.

The drive timings of the LED array control section 10 and the LED array head 3 are the same as in the sixth embodiment, and a description thereof will be omitted.

The acquisition of correction data written and stored in advance in the correction data storage unit 35 will be described. As shown in FIG. 30, before the factory shipment, the correction data is acquired by the image writing device 37 and the pitch correction data generation device 6 between the beam spots.
Performed using 0. The beam spot pitch correction data generation device 60 is detachably connected to the multi-level conversion unit 32 of the image writing device 37 by an interface (not shown), and is adjacent to a controller 61 containing a microcomputer. A beam spot pitch measuring device 62 for measuring a beam spot pitch when the LED element 16 is turned on and outputting the measurement result to a controller 61;
Measurement condition setting unit 63 for setting measurement conditions by
And the image writing device 3 under the control of the controller 61.
It comprises a correction data setting section 64 for outputting 8-bit correction data to the multi-value conversion section 32 of 7 and a correction data storage device 65 for recording the correction data when the correction data is determined.

In order to set the pitch between the beam spots of the adjacent LED elements 16 to a desired pitch P, the individual electrodes 21a and 21
The process of obtaining the pitch correction data between beam spots in b will be described with reference to the flowchart shown in FIG. Here, the measurement condition corresponding to the image forming condition such as the exposure condition is Cy (y = 1 to Y: Y is arbitrary), and this condition is set because the pitch between the beam spots changes according to the set light amount and the threshold level. This is because the pitch between the dots formed thereby changes, so that the measurement condition setting unit 6 matches one of the exposure conditions at the time of actual image writing.
3 is set.

In this embodiment, each LED element 16 (N
The number of individual electrodes in the two (individual electrodes 21a, 21a)
1b). Therefore, the acquired correction data is N
× 2, and there are two correction data for one LED element 16, and there are apparently twice as many LED elements.

First, it is checked whether a specified pitch P has been set. When the specified pitch P is set, it is checked whether the measurement condition Cy (y = 1) is set. The measurement condition C1 is set by the measurement condition setting unit 63, and when various settings are completed, n = 1 is set in order to target the dot 1 (the LED element of No. 1). Next, the correction data M1
ny (meaning the correction data by the individual electrode 1 (= individual electrode 21a) for the n-th LED element in the measurement condition y: here, the measurement condition is C1 and the first LED element 1
6), M2ny (meaning correction data by the individual electrode 2 (= individual electrode 21b) for the n-th LED element in the measurement condition y: Here, the measurement condition is C1 and the first LE
D element 16) is assumed to be '128' (= '1,000,000)
0 '). However, there is no meaning limited to this numerical value, and "0" to "255" represented by 8-bit data
And a value expected to be the closest to a desired pitch P based on existing experimental data and the like.

The correction data M1ny and M2ny are stored in the correction data storage device 65, and the correction data setting section 6
4 and is given to the multi-level conversion unit 32 side, and the dot n, here the dot 1 (the LED element 16 of No. 1), is set to L by the individual electrodes 1 and 2 (= the individual electrodes 21a and 21b).
It is turned on by the ED array drive unit 11. The lighting timing at this time is shown in FIG.

Next, dot 2 (LED element 1 of No. 2)
In order to make 6) a target, n is incremented by +1. Then, the correction data M1ny (meaning the correction data by the individual electrode 1 (= individual electrode 21a) for the n-th LED element 16 in the measurement condition y: here, the measurement condition is C1, the second LED element 1 + 6), M2ny (Individual electrode 2 for n-th LED element 16 under measurement condition y
(= Individual electrode 21b): It means that the measurement condition is C1 and the second LED element 16) is temporarily set to '128' (= '10000000').
The setting values are the same as above. Then, the correction data M1ny and M2ny are set in the correction data setting unit 64 and provided to the multi-value conversion unit 32, and the dot n, here, dot 2 (the LED element 16 of No. 2) is converted by the LED array driving unit 11. Turn on.

At this time, the pitch Pp between the spots of the two lighting dots is measured by the pitch measuring device 62 between the beam spots.
And sends the measurement result to the controller 61. The controller 61 having received the measurement result checks whether or not the pitch Pp between the spots is almost equal to the pitch P between the specified spots. If they are still not substantially equal, the correction data M1ny, M2
By increasing or decreasing the value of ny (for example, '1
Change to 29 or to 127
The increase / decrease width is not limited to '1', and the correction data may be changed according to M1ny and M2ny.) The spot pitch Pp of the dots (in this case, dot 1 and dot 2) to be lit according to the correction data is measured again. Is repeated until the inter-spot pitch Pp becomes almost equal to the specified inter-spot pitch P. Originally, the determination that they are almost equal should be made as to whether or not the two are completely equal. However, the determination is not always necessary due to the number of bits of the correction data M1ny and M2ny, the measurement error of the pitch Pp between spots, and the like. Since it is considered that they may not be the same, if the data is within the allowable approximation range, it is determined that the data is normal. This approximation range is determined in consideration of the number of bits of the correction data M1ny and M2ny, the measurement error of the pitch Pp between spots, the variation range of the pitch between spots that is allowable as the target image quality when an image is actually formed, and the like. You.

When the measured inter-spot pitch Pp becomes substantially equal to the specified inter-spot pitch P, the measurement conditions C
Correction data M1 for dot n at y (y = 1)
ny and M2ny are stored in the correction data storage device 65.
The correction data M1ny and M2ny at this time are numerical values set in the correction data setting unit 64 at that time. Thereafter, the dot n−1, here, dot 1 (the LED element 16 of No. 1) is turned off, and the next dot n, here, dot 3
In order to target (No. 3 LED element 16), n is incremented by +1. At this point, it is checked whether or not the number of new dots n does not exceed the total number N. If not, the above process is repeated for dot n. Accordingly, for all the dots n (n = 1 to N) in the measurement condition Cy (y = 1), the adjacent LEs
Correction data M1ny and M2ny for setting the pitch Pp between spots of the D element to the specified pitch P between spots are stored in the correction data storage device 65.

When this process is completed, all dots are turned off, and it is checked whether or not there are other measurement conditions Cy. If there are any other measurement conditions Cy, those measurement conditions Cy (y = 2), Cy (y = 3),
.., Cy (y = Y), and the above-described acquisition and storage processing of the correction data M1ny and M2ny is repeated for each measurement condition.

Therefore, after all the measurements are completed, the correction data storage device 65 stores the measurement condition correction data C1 M111 M211 M121 M221 M131 M231... M1N1 M2N1 C2 M112 M212 M122 M222 M132 M232. M12Y, M22Y, M13Y, M23Y... M1NY M2NY, correction data M1n for each individual electrode 21a, 21b at each dot in the form of using each measurement condition Cy as an address.
y and M2ny are stored. The correction data M stored in such a correction data storage device 65
1ny and M2ny are written into the correction data storage unit 35 of the LED array control unit 10 using a ROM writer or the like, and are used at the time of actual image writing.

The correction data M1n for each such condition
correction data storage section 35 in which y and M2ny are written
When the image is actually written by the LED array control unit 10 using, the desired image forming conditions are set by the image writing condition setting unit 36 and the image writing is started.
At this time, the correction data M1ny and M2ny corresponding to the condition Cy are read from the correction data storage unit 35 and output to the multi-value conversion unit 32.

In this embodiment, correction data for one kind of spot pitch P is obtained. However, various kinds of spot pitches and various images can be set so that various settings can be made for the spot pitch. Correction data for setting the various spot pitches Px for each forming condition may be obtained. In this case, the correction data storage unit 35 stores correction data for setting the pitch Px between various spots for each pitch between various spots and for each image forming condition. FIG. 31 shows a process of acquiring correction data.
Processing for determining whether or not x exists is added.

In this embodiment, the LED element 16
Of the two individual electrodes 21 as in the first embodiment.
a, 21b (individual electrodes 21d, 21d of the third embodiment)
e), but the present invention is not limited to this. The number of spots may be three or more as in the second, fourth, and fifth embodiments. Can be uniform.

A thirteenth embodiment of the present invention will be described with reference to FIGS. This embodiment is also described in claim 1.
This corresponds to the inventions described in 9 and 20.

The image forming unit of the LED array printer is the same as in the first embodiment, and will not be described.

The drive timings of the LED array control unit 10 and the LED array head 3 are the same as in the sixth embodiment, and will not be described.

FIG. 32 shows an apparatus for acquiring correction data. The difference from the twelfth embodiment is that the pitch between beam spots when each LED element 16 is turned on is measured and the result is obtained. The beam spot pitch measuring device 60 that outputs a measurement result to the controller 61 is provided with a beam spot diameter measuring device 66 that measures the beam spot diameter of each LED element 16 and outputs the measurement result to the controller 61. And each L for correcting to a specified beam spot diameter under the control of the controller 61.
A second correction data storage device 67 that can temporarily store correction data by the individual electrodes 21a and 21b of the ED element 16 and can read out the stored correction data when obtaining correction data of the pitch between beam spots. It is a point that is provided. Note that the correction data storage device 65 in the above embodiment is a first correction data storage device. Other points are the same as in the twelfth embodiment, and a description thereof will be omitted.

In order to set the pitch between beam spots of adjacent LED elements 16 to a desired pitch P, each of the individual electrodes 21a and 21
The process of acquiring the pitch correction data between beam spots in b will be described with reference to the flowchart shown in FIG. In the present embodiment, processing for correcting the beam spot diameter of each LED element 16 to a specified value is added to the processing of the twelfth embodiment.

Here, the measurement condition corresponding to the image forming condition such as the exposure condition is C, and this condition is set because the pitch between the beam spots changes depending on the set light amount and the threshold level, and the dot interval formed by the beam spot changes. This is because the pitch changes, and is set by the measurement condition setting unit 63 in accordance with one of the exposure conditions at the time of actual image writing.

In the present embodiment, each LED element 16 (N
The number of individual electrodes in the two (individual electrodes 21a, 21a)
1b). Therefore, the acquired correction data is N
× 2, and there are two correction data for one LED element 16, and there are apparently twice as many LED elements.

First, it is checked whether a specified spot diameter D has been set. When the specified spot diameter D is set,
It is checked whether the measurement condition C has been set. Measurement condition C
Is set by the measurement condition setting unit, and when various settings are completed, n = 1 is set in order to target the dot 1 (the LED element 16 of No. 1). Next, the correction data M1n (n
Individual electrode 1 for the LED element (= individual electrode 21a)
Means the correction data by: here the first LED
Element 16), M2n (meaning the correction data by the individual electrode 2 (= individual electrode 21b) for the nth LED element:
Here, the first LED element 16) is assumed to be “128”.
(= '10000000'). However, there is no meaning limited to this numerical value, and it is a numerical value in the range of '0' to '255' indicated by 8-bit data, and is the closest to the desired spot diameter D based on existing experimental data and the like. Use the expected value.

The correction data M1n and M2n are set in the correction data setting section and provided to the multi-value conversion section 32, where the individual electrodes 1 and 2 (= individual electrodes 21a and 21b) perform dot n, here dot 1 ( The No. 1 LED element 16) is turned on by the LED array drive unit 11. The lighting timing at this time is shown in FIG. At this time, the spot diameter Dd of the dot n is measured by the beam spot diameter measuring device 66, and the measurement result is sent to the controller 61.
The controller 61 receiving the measurement result checks whether or not the beam spot diameter Dd is almost equal to the specified spot diameter D. If they are still not substantially equal, the values of the correction data M1n, M2n are increased or decreased (for example, changed to '129' or changed to '127') according to the magnitude relation between them. But the increase / decrease range is '1'
The correction data may be changed for each of M1n and M2n), and the beam spot diameter Dd of the dot n to be lit according to the correction data is measured again.
This is repeated until d becomes almost equal to the specified beam spot diameter D. The judgment that they are almost equal should be a judgment of whether or not they are completely equal.
It is conceivable that the correction data M1n and M2n may not always be equal due to the number of bits of the data, the measurement error of the beam spot diameter Dd, and so on. I am trying to do it. The approximation range is determined in consideration of the number of bits of the correction data M1n and M2n, the measurement error of the beam spot diameter Dd, the variation range of the beam spot diameter that is allowable as the target image quality when an image is actually formed, and the like. You.

When the measured beam spot diameter Dd becomes substantially equal to the specified beam spot diameter D, the measurement condition C
The correction data M1n and M2n for the dot n in are stored in the second correction data storage device 67. The correction data M1n and M2n at this time are stored in the correction data setting unit 64 at that time.
Is the number that was set to. Thereafter, dot n, here dot 1 (No. 1 LED element 16), is turned off, and the next dot n, here dot 2 (No. 2 LED element 1), is turned off.
In order to make 6) a target, n is incremented by +1. At this time, it is checked whether or not the new dot n does not exceed the total number N.
Is repeated in the same manner. Thereby, the correction data M1n and M2n for setting the beam spot diameter Dd to the specified beam spot diameter D for all the dots n (n = 1 to N) in the measurement condition C are stored in the second correction data storage device 67. Is stored.

Next, it is checked whether a specified beam spot pitch P has been set. When the prescribed pitch P between beam spots is set, n = 1 is set in order to target the dot 1 (the LED element 16 of No. 1). Next, the correction data M1n (meaning correction data by the individual electrode 1 (= individual electrode 21a) for the n-th LED element: here, the first LED element 16), M2n (the individual LED for the n-th LED element) The correction data by the electrode 2 (= individual electrode 21b: here, the first LED element) is read from the second correction data storage device 67. The correction data M1n and M2n are stored in the first correction data storage device 65, and are further set in the correction data setting unit 64.
The dot n, here the dot 1 (the LED element 16 of No. 1), is supplied to the multi-value conversion section 32 by the individual electrodes 1 and 2 (= individual electrodes 21 a and 21 b), and is lit by the LED array driving section 11.

Next, n is incremented by +1 in order to target dot 2 (the LED element of No. 2).
Then, the correction data M1n (meaning the correction data by the individual electrode 1 (= individual electrode 21a) for the n-th LED element 16: here, the second LED element 16), M2n
(The individual electrode 2 for the n-th LED element (= the individual electrode 21
b) means the correction data according to: here the second L
The ED element 16) is read out from the second correction data storage device 67, and is set in the correction data setting section 64.
1a, 21b)) by dot n, here dot 2
(No. 2 LED element 16) to LED array drive unit 11
To light up.

At this time, the pitch Pp between the spots of the two lighting dots is measured by the pitch measuring device 66 between the beam spots.
And sends the measurement result to the controller 61. The controller 61 having received the measurement result checks whether or not the pitch Pp between the spots is almost equal to the pitch P between the specified spots. If they are still not substantially equal, the correction data M1n, M2n
Increase or decrease the value (the increase / decrease range is '1'
The correction data may be changed according to the correction data M1n and M2n), and the pitch Pp between the spots of the dots (in this case, dot 1 and dot 2) to be lit according to the correction data is measured again. This is repeated until the pitch between the spots becomes almost equal to the pitch P. The determination that they are almost equal should be a determination as to whether or not both are completely equal, but the correction data M1n, M2n
It is conceivable that the data may not always be equal due to the relationship between the number of bits and the measurement error of the pitch Pp between spots, so that if the data is within an acceptable approximation range, it is determined that the data is normal. . The approximate range is the number of bits of the correction data M1n and M2n, and the pitch Pp between spots.
Is determined in consideration of the measurement error, the variation range of the pitch between spots that is allowable as the target image quality when an image is actually formed, and the like.

When the measured inter-spot pitch Pp becomes substantially equal to the specified inter-spot pitch P, the measurement condition C
The correction data M1n and M2n for the dot n in are stored in the first correction data storage device 65. The correction data M1n and M2n at this time are stored in the correction data setting unit 64 at that time.
Is the number that was set to. Thereafter, the dot n-1, here dot 1 (the LED element 16 of No. 1) is turned off,
In order to target the next dot n, here dot 3 (the LED element 16 of No. 3), n is incremented by +1. At this point, it is checked whether or not the number of new dots n does not exceed the total number N. If not, the above process is repeated for dot n. This allows
For all dots n (n = 1 to N) in the measurement condition C, correction data M1n for setting the pitch Pp between spots of adjacent LED elements to the specified pitch P between spots,
M2n is stored in the first correction data storage device 65.

When this process is over, all dots are turned off.

Therefore, after all the measurements have been completed, the first correction data storage device 65 stores the LED element 16 like the measurement condition C; LED No. correction data 1 M11 M21 2 M12 M22... N M1N M2N. No. , The correction data M1n and M2n for each individual electrode 21a and 21b in each dot are stored. The correction data M1n and M2n stored in the first correction data storage device 65 are written into the correction data storage unit 35 of the LED array control unit 10 using a ROM writer or the like.
Used during actual image writing.

When an image is actually written by the LED array control unit 10 using the correction data storage unit 35 into which such correction data M1n and M2n are written, the image writing condition setting unit 36 A desired image forming condition is set, and writing of an image is started. At this time, the correction data M1n and M2n corresponding to the condition C are read from the correction data storage unit 35 and output to the multi-value conversion unit 32. Is done.

In this embodiment, correction data for one type of image forming condition C (measurement condition), one type of beam spot diameter D, and one type of pitch P between spots is obtained. Correction data that allows various settings to be made for all or all of the units may be obtained. In this case, the correction data storage unit 35 stores, for example, correction data for setting the pitch Px between various spots for each pitch between spots, for each spot diameter, and for each image forming condition. Then, at the time of actual image formation, various conditions are set from the image writing condition setting unit 36, and correction data suitable for the conditions is read.

In the present embodiment, the LED element 16
Of the two individual electrodes 21 as in the first embodiment.
a, 21b (individual electrodes 21d, 21d of the third embodiment)
e), but the present invention is not limited to this. The number of spots may be three or more as in the second, fourth, and fifth embodiments. Can be uniform.

[0222]

According to the first aspect of the present invention, in the LED element, attention is paid to the point that the emission intensity is increased at the individual electrode portion provided for the light emitting portion, and the individual electrode is provided for each LED element. Since it is provided in a state of being divided into a plurality of parts, by controlling the arrangement, shape, amount of electricity, and the like, it is possible to suppress the unevenness and variation of the light amount distribution of each LED element, and it is possible to suppress white stripes and black on the image. In addition to suppressing the occurrence of vertical stripes such as streaks, it is also possible to form dots as many as the individual electrodes by controlling each individual electrode separately, and it is possible to increase the apparent resolution Become.

According to the second aspect of the present invention, in order to realize the first aspect of the present invention, as an example, in particular, the individual electrodes are provided at both ends of the light emitting section in the main scanning direction. Unevenness and variation in the light amount distribution of the element in the main scanning direction can be suppressed, and therefore, occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed.

According to the third aspect of the present invention, in order to realize the first aspect of the present invention, as an example, individual electrodes are provided at both ends of the light emitting portion in the main scanning direction and at an intermediate portion thereof. Therefore, it is possible to suppress the unevenness and dispersion of the light amount distribution in the main scanning direction of each LED element, thereby suppressing the occurrence of vertical stripes such as white stripes and black stripes on an image,
Since the individual electrodes are also provided in the middle part in the main scanning direction, the bias can be further suppressed.

According to the fourth aspect of the present invention, in order to realize the first aspect of the present invention, as an example, in particular, since the individual electrodes are provided at both ends of the light emitting section in the sub-scanning direction, each L
Unevenness and variation of the light amount distribution in the sub-scanning direction of the ED element can be suppressed, and therefore, occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed.

According to the fifth aspect of the present invention, in order to realize the fourth aspect of the present invention, as an example, the individual electrodes provided at both ends of the light emitting section in the sub-scanning direction are particularly provided at both ends in the main scanning direction. Since each of the LED elements is divided into four individual electrodes, deviations and variations in the light amount distribution in the main scanning direction and the sub-scanning direction of each LED element can be suppressed. The generation of vertical stripes such as black stripes can be suppressed.

According to the sixth aspect of the present invention, in order to realize the third aspect of the present invention, as an example, in particular, individual electrodes provided at both ends of the light emitting section in the main scanning direction and intermediate portions thereof are provided. By dividing at both ends in the scanning direction, 6
Since the individual electrodes are used, deviations and variations in the light amount distribution in the main scanning direction and the sub-scanning direction of each LED element can be suppressed as much as possible, so that vertical stripes such as white stripes and black stripes on the image are generated. Can be suppressed.

According to the seventh aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects, the light emission of each LED element is adjusted so that the light amount distribution of each LED element has a desired shape. By controlling the energizing operation to the plurality of individual electrodes on the unit, the light amount distribution can be made uniform, so that the occurrence of vertical stripes such as white stripes and black stripes on the image can be suppressed.

According to the eighth aspect of the invention, when an image is formed by the LED array head, the correction data corresponding to the individual electrode of each LED element is read out from the storage section, and the drive control means is individually used by using the correction data. By controlling the energizing operation to the electrodes, the light amount distribution of each LED element can be made to have a desired shape, and therefore, the occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed, An example for realizing the invention described in claim 7 can be provided.

According to the ninth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects, each light intensity distribution at each individual electrode of each LED element has a desired shape. By controlling the energizing operation of the plurality of individual electrodes on the light emitting portion of the LED element, the light amount distribution can be made uniform, and thus the occurrence of vertical stripes such as white stripes and black stripes on the image is suppressed. be able to.

According to the tenth aspect, when an image is formed by the LED array head, the correction data corresponding to the individual electrode of each LED element is read out from the storage section, and the drive control means individually uses the correction data. By controlling the energizing operation to the electrodes, the light quantity distribution in each individual electrode of each LED element can be made to have a desired shape, thereby suppressing the occurrence of vertical stripes such as white stripes and black stripes on an image. Thus, an example for realizing the invention described in claim 9 can be provided.

According to the eleventh aspect of the present invention, each LED
By controlling the energizing operation to a plurality of individual electrodes on the light emitting portion of each LED element so that the light quantity of the element becomes a desired value, the light quantity can be made uniform, so that white stripes and The generation of vertical stripes such as black stripes can be suppressed.

According to the twelfth aspect of the present invention, when an image is formed by the LED array head, the correction data corresponding to the individual electrodes of each LED element is read out from the storage section, and the drive control means uses the correction data to cause the drive By controlling the energizing operation for the LED, the light amount of each LED element can be set to a desired value, and therefore, the occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed,
An example for realizing the invention described in claim 11 can be provided.

According to the thirteenth aspect of the present invention, in the LED array printer according to any one of the first to sixth aspects, each of the LED elements is arranged such that the amount of light at each individual electrode of each LED element has a desired value. By controlling the energizing operation for a plurality of individual electrodes on the light emitting portion, the light amount can be made uniform, and thus the occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed. .

According to the fourteenth aspect of the present invention, when an image is formed by the LED array head, the correction data corresponding to the individual electrode of each LED element is read out from the storage unit, and the drive control means individually uses the correction data. By controlling the energizing operation to the electrodes, the light amount at each individual electrode of each LED element can be set to a desired value, and therefore, the occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed. Thus, an example for realizing the invention according to claim 13 can be provided.

According to the fifteenth aspect, the first aspect is provided.
In the LED array printer according to any one of (1) to (6), by controlling the energizing operation to a plurality of individual electrodes on the light emitting unit of each LED element so that the spot diameter of each LED element has a desired value, The spot diameter can be made uniform, so that the occurrence of vertical stripes such as white stripes and black stripes on the image can be suppressed.

According to the sixteenth aspect, when an image is formed by the LED array head, the correction data corresponding to the individual electrode of each LED element is read out from the storage section, and the drive control means is individually used by using the correction data. By controlling the energizing operation to the electrodes, the spot diameter in each LED element can be set to a desired value,
It is possible to suppress the occurrence of vertical streaks such as white streaks and black streaks on an image, and it is possible to provide an example for realizing the invention according to claim 15.

According to the seventeenth aspect, in the first aspect,
7. In the LED array printer according to any one of the above items 6, the energizing operation of the plurality of individual electrodes on the light emitting portion of each LED element is controlled such that the spot diameter at each individual electrode of each LED element has a desired value. By doing so, the spot diameter can be made uniform, and thus the occurrence of vertical stripes such as white stripes and black stripes on the image can be suppressed.

According to the eighteenth aspect, at the time of image formation by the LED array head, the correction data corresponding to the individual electrode of each LED element is read from the storage section, and the drive control means is individually used by using the correction data. By controlling the energizing operation to the electrodes, the spot diameter at each individual electrode of each LED element can be set to a desired value, thereby suppressing the occurrence of vertical stripes such as white stripes and black stripes on an image. Thus, an example for realizing the invention described in claim 17 can be provided.

According to the invention of claim 19, claim 1
In the LED array printer according to any one of (6) to (7), the energizing operation of the plurality of individual electrodes on the light emitting unit of each LED element is controlled so that the pitch between the spots of each LED element becomes a desired value. In addition, the pitch between spots can be made uniform, so that the occurrence of vertical stripes such as white stripes and black stripes on an image can be suppressed.

According to the twentieth aspect, at the time of image formation by the LED array head, the correction data corresponding to the individual electrodes of each LED element is read from the storage unit, and the drive control means is individually used by using the correction data. By controlling the energizing operation to the electrodes, the pitch between the spots of each LED element can be set to a desired value.
It is possible to suppress the occurrence of vertical stripes such as white stripes and black stripes on an image, and it is possible to provide an example for realizing the invention according to claim 19.

According to the twenty-first aspect of the present invention, when gradation is expressed by the area gradation method using the one-dot binary method, dots are formed at a certain threshold level. By setting the threshold level so as not to be affected by the drop in the amount of light due to the plurality of individual electrodes, it is possible to prevent white spots in the center of the dot and a density difference between the center and the periphery of the dot, As compared with the one-dot multi-value method, the degree of freedom in setting the threshold level and the margin are increased, the image quality can be further stabilized, and the correction data for making the spot diameter and the like uniform is also certain. Since only one spot diameter or the like needs to be considered, the entire control system can be simplified.

[Brief description of the drawings]

FIG. 1 is a schematic side view illustrating a configuration example of an image forming unit according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration example of an LED array head driving unit.

FIG. 3 is a time chart showing a drive timing of the LED array head.

FIG. 4 is a block diagram illustrating a configuration example of an image writing control unit.

FIG. 5 is an explanatory diagram showing both a structure near a light emitting portion of a certain LED element and a light amount distribution in the present embodiment.

6A is a plan view showing a configuration example of an LED array head, FIG. 6B is a characteristic diagram showing a light amount distribution of each LED element in a sub-scanning direction, and FIG. 6C is a main scanning of each LED element. FIG. 3D is a characteristic diagram showing a light amount distribution in the direction, and FIG. 4D is an explanatory diagram showing an example of image forming dots for each LED element.

FIG. 7 is an explanatory diagram showing both a structure near a light emitting portion of a certain LED element and a light amount distribution in a second embodiment of the present invention.

8A is a plan view showing a configuration example of an LED array head, FIG. 8B is a characteristic diagram showing a light amount distribution of each LED element in a sub-scanning direction, and FIG. 8C is a main scanning of each LED element. FIG. 3D is a characteristic diagram showing a light amount distribution in the direction, and FIG. 4D is an explanatory diagram showing an example of image forming dots for each LED element.

FIG. 9 is an explanatory diagram showing a structure near a light-emitting portion of a certain LED element and a light amount distribution according to a third embodiment of the present invention.

10A is a plan view showing a configuration example of an LED array head, FIG. 10B is a characteristic diagram showing a light amount distribution of each LED element in a sub-scanning direction, and FIG. 10C is a main scanning of each LED element. FIG. 3D is a characteristic diagram showing a light amount distribution in the direction, and FIG. 4D is an explanatory diagram showing an example of image forming dots for each LED element.

FIG. 11 is an explanatory diagram showing a structure near a light emitting portion of a certain LED element and a light amount distribution in a fourth embodiment of the present invention.

12A is a plan view illustrating a configuration example of an LED array head, FIG. 12B is a characteristic diagram illustrating a light amount distribution of each LED element in a sub-scanning direction, and FIG. 12C is a main scanning of each LED element. FIG. 3D is a characteristic diagram showing a light amount distribution in the direction, and FIG. 4D is an explanatory diagram showing an example of image forming dots for each LED element.

FIG. 13 is an explanatory diagram showing a structure near a light emitting portion of a certain LED element and a light amount distribution according to a fifth embodiment of the present invention.

14A is a plan view showing a configuration example of an LED array head, FIG. 14B is a characteristic diagram showing a light amount distribution of each LED element in a sub-scanning direction, and FIG. 14C is a main scanning of each LED element. FIG. 4D is a characteristic diagram showing a light amount distribution in a direction, and FIG.

FIG. 15 is a block diagram illustrating a configuration example of an image writing control unit according to a sixth embodiment of the present invention.

FIG. 16 is a block diagram illustrating a configuration example of an image writing device and a light amount distribution correction data generation device.

FIG. 17 is a time chart showing an example of drive timing.

FIG. 18 is a flowchart illustrating an example of a process for acquiring light amount distribution correction data.

FIG. 19 is a time chart illustrating an example of drive timing.

FIG. 20 is a flowchart illustrating a process of acquiring light amount distribution correction data according to the seventh embodiment of the present invention.

FIG. 21 is a time chart showing an example of drive timing.

FIG. 22 is an explanatory diagram showing the structure of the light emitting portion of the LED element, its light amount distribution in the main and sub scanning directions, and dots to be formed.

FIG. 23 is a block diagram illustrating a configuration example of an image writing control unit according to an eighth embodiment of the present invention.

FIG. 24 is a block diagram illustrating a configuration example of an image writing device and a light amount correction data generation device.

FIG. 25 is a flowchart illustrating a process of acquiring light amount correction data for each individual electrode.

FIG. 26 is a flowchart showing a process for acquiring light quantity correction data for each individual electrode according to the ninth embodiment of the present invention.

FIG. 27 is a block diagram illustrating a configuration example of an image writing device and a beam spot diameter correction data generation device according to a tenth embodiment of the present invention.

FIG. 28 is a flowchart showing a process for acquiring beam spot diameter correction data for each individual electrode.

FIG. 29 is a flowchart illustrating a process of acquiring beam spot diameter correction data for each individual electrode according to the eleventh embodiment of the present invention.

FIG. 30 is a block diagram illustrating a configuration example of an image writing device and a beam spot pitch correction data generation device according to a twelfth embodiment of the present invention.

FIG. 31 is a flowchart showing a process for acquiring pitch correction data between beam spots in each individual electrode.

FIG. 32 is a block diagram illustrating a configuration example of an image writing device and a beam spot pitch correction data generation device according to a thirteenth embodiment of the present invention.

FIG. 33 is a flowchart showing a process for acquiring pitch correction data between beam spots in each individual electrode.

FIG. 34 is an explanatory diagram showing an example of a conventional dot shape in which vertical streaks occur due to variations in light amount distribution.

35A and 35B show a conventional example, in which FIG. 35A is a plan view showing an LED array head structure, FIG. 35B is a characteristic diagram showing a light amount distribution of each LED element in the sub-scanning direction, and FIG. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image carrier 16 LED element 20 Light emitting part 21a-21m Individual electrode 35 Storage part

Claims (21)

[Claims] 1. A light emitting portion of a large number of LED elements is arranged in a line along a main scanning direction, and each LED element is controlled to be turned on according to image information, and a latent image corresponding to the image information is carried on an image. An LED array printer formed on a body, comprising: a plurality of individual electrodes for a light emitting portion of each of the LED elements. 2. The LED array printer according to claim 1, wherein the individual electrodes of each of the LED elements are provided separately at both ends in the main scanning direction of the light emitting unit. 3. The LED according to claim 1, wherein the individual electrodes of each of the LED elements are provided so as to be divided into both ends of the light emitting section in a main scanning direction and an intermediate part thereof. Array printer. 4. The LED array printer according to claim 1, wherein the individual electrodes of each of the LED elements are provided so as to be divided at both ends in the sub-scanning direction of the light emitting section. 5. The LED array printer according to claim 4, wherein the individual electrodes of each of the LED elements are divided with respect to both ends of the light emitting unit in the main scanning direction. 6. The LED array printer according to claim 3, wherein the individual electrodes of each of the LED elements are divided with respect to both ends in the sub-scanning direction of the light emitting unit. 7. An LED according to claim 1, further comprising: controlling an energizing operation of each of said LED elements to a plurality of individual electrodes on said light emitting portion.
The LED array printer according to any one of claims 1 to 6, wherein a light amount distribution of the element is formed in a desired shape. 8. A storage unit for storing correction data for making a light quantity distribution of each of the LED elements turned on by energizing the individual electrodes into a desired shape, and a storage unit for storing correction data corresponding to each of the LED elements. And a correction data reading means for reading out each of the L by using the read out correction data.
The LED array printer according to any one of claims 1 to 6, further comprising: drive control means for controlling an energizing operation of the ED element to the individual electrodes. 9. A method for controlling the energizing operation of each of the LED elements to a plurality of individual electrodes on the light emitting section, thereby controlling each of the LED elements
The LED array printer according to any one of claims 1 to 6, wherein a light quantity distribution in each of the individual electrodes of the element is formed in a desired shape. 10. A storage unit for storing correction data for making a light quantity distribution in each of said individual electrodes of each of said LED elements turned on by energization of said individual electrodes into a desired shape, and a corresponding correction for each of said LED elements 2. The apparatus according to claim 1, further comprising: a correction data reading unit that reads data from the storage unit; and a drive control unit that controls an energization operation of each of the LED elements to the individual electrode using the read correction data. 6. The LE according to any one of to 6
D array printer. 11. A method of controlling a current supply operation of each of the LED elements to a plurality of individual electrodes on the light emitting section to thereby control each of the LEs.
7. The LED array printer according to claim 1, wherein the light intensity of the D element is set to a desired value. 12. A storage unit storing correction data for setting a light amount of each of the LED elements to be turned on by energizing the individual electrode to a desired value, and a correction data corresponding to each LED element from the storage unit. A correction data reading means for reading, and each of the LEDs using the read correction data;
The LED array printer according to any one of claims 1 to 6, further comprising: drive control means for controlling an energizing operation of the element to the individual electrodes. 13. A method of controlling a current supply operation of each of the LED elements to a plurality of individual electrodes on the light-emitting section to thereby control each of the LEs.
The LED array printer according to any one of claims 1 to 6, wherein a light amount at each of the individual electrodes of the D element is set to a desired value. 14. A storage unit for storing correction data for setting a light amount at each of said individual electrodes of each of said LED elements to be turned on by energization of said individual electrodes to a desired value;
Correction data readout means for reading out the corresponding correction data for the ED element from the storage unit, and drive control means for controlling the energizing operation of the individual electrodes of the LED elements using the readout correction data. The LED array printer according to any one of claims 1 to 6, wherein: 15. Controlling a current supply operation of each of the LED elements to a plurality of individual electrodes on the light-emitting section to thereby control each of the LEs
7. The LED array printer according to claim 1, wherein a spot diameter of the D element is set to a desired value. 16. A storage unit for storing correction data for setting a spot diameter of each of the LED elements turned on by energizing the individual electrode to a desired value, and storing the correction data corresponding to each of the LED elements in the storage unit. 7. A correction data reading means for reading data from the memory, and a drive control means for controlling an energizing operation of each of the LED elements to the individual electrode using the read correction data. The LED array printer according to claim 1. 17. Controlling an energizing operation of each of the LED elements to a plurality of individual electrodes on the light emitting section to thereby control each of the LEs
The LED array printer according to any one of claims 1 to 6, wherein a spot diameter of each of the individual electrodes of the D element is set to a desired value. 18. A storage unit for storing correction data for setting a spot diameter of each of said LED elements to be turned on by energization of said individual electrode at said individual electrode to a desired value, and a correction corresponding to each of said LED elements. 2. The apparatus according to claim 1, further comprising: a correction data reading unit that reads data from the storage unit; and a drive control unit that controls an energization operation of each of the LED elements to the individual electrode using the read correction data. 6. The LE according to any one of to 6
D array printer. 19. Controlling the energizing operation of each of the LED elements to a plurality of individual electrodes on the light emitting section, and
7. The LED array printer according to claim 1, wherein a pitch between spots of the D element is set to a desired value. 20. A storage unit storing correction data for setting a pitch between spots of each of the LED elements to be turned on by energizing the individual electrodes to a desired value, and storing the correction data corresponding to each LED element. 7. A device according to claim 1, further comprising: correction data reading means for reading out from said unit; and drive control means for controlling an energizing operation of said LED elements to said individual electrodes using said read out correction data. 9. The LED array printer according to claim 1. 21. The LED array printer according to claim 1, wherein said image information is one-dot binary data.