JP2003182154A - Image exposing device and method for setting operational conditions of exposing head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress variation in the light emission of an optical shutter array provided in an exposing head from a regulation target value as much as possible. <P>SOLUTION: The image exposing device comprises an exposing head EH forming an optical shutter array of PLZT elements by arranging a plurality of PLZT array chips 41, each having the PLZT elements arranged in the main scanning direction, in the main scanning direction, and means for measuring emission of light from the PLZT elements. The degree of correction in the exposure driving conditions of the PLZT elements for the difference between measurements by the measuring means and a regulation target value is differentiated between a plurality of PLZT elements from the end thereof and the remaining central PLZT elements arranged in the main scanning direction within one PLZT array chip. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides an optical shutter array using the PLZT elements by arranging a plurality of PLZT array chips in which the PLZT elements are arranged in the main scanning direction and integrated on one chip in the main scanning direction. An exposure head to be formed, measuring means for measuring the amount of light emitted from the PLZT element, and each PLZ based on the measurement result.
The present invention relates to an image exposure apparatus provided with an operation condition setting means for setting an exposure drive condition for a T element, and an operation condition setting method for an exposure head for setting the exposure drive condition in this image exposure apparatus.

[0002]

2. Description of the Related Art Such an image exposure apparatus comprises a PLZT element to constitute an optical shutter corresponding to a pixel of an image to be exposed, and a plurality of such optical shutters are arranged in the main scanning direction to form an exposure based on image data to be formed. In this way, each optical shutter is individually driven to form an exposure image on, for example, a photographic photosensitive material. Ideally, each optical shutter of the exposure head emits the same amount of light with respect to the same drive input, but in reality, the same drive is applied to the PLZT elements constituting each optical shutter due to manufacturing variations and the like. Even if an input is applied, the amount of emitted light varies. Therefore, the amount of light emitted from the optical shutter is measured, and the exposure drive condition of each PLZT element, that is, the correspondence between the input gradation value and the amount of light emitted is adjusted based on the measurement result. This PLZT
The conventional method for adjusting the exposure drive condition of the element is to drive the exposure head with the image data for adjustment and read the image formed on the photographic light-sensitive material with the image reading device, and read the read density information. On the basis of the above, the exposure drive condition is corrected so that the variation of the amount of light emitted from the optical shutter from the adjustment target is sufficiently small.

[0003]

However, in the above-mentioned conventional configuration, when the image formed by exposure with the image data for adjustment is carefully observed, an extremely thin band-like pattern extending in the sub-scanning direction orthogonal to the main scanning direction is formed. In some cases, even if the adjustment work by the above method is repeated, it may not be possible to sufficiently suppress the variation in the amount of light emitted from the optical shutter from the adjustment target. The present invention has been made in view of the above circumstances, and its purpose is to:
This is to suppress the variation of the amount of light emitted from the optical shutter array provided in the exposure head from the adjustment target as much as possible.

[0004]

According to the structure described in claim 1, a plurality of PLZT array chips in which PLZT elements are arranged in the main scanning direction and integrated in one chip are arranged in the main scanning direction. By the above P
An exposure head for forming an optical shutter array of LZT elements, a measuring means for measuring the amount of light emitted from the PLZT elements, and an operating condition setting means for setting the exposure driving condition of each PLZT element based on the measurement result are provided. In the image exposure apparatus described above, the operating condition setting means includes one P
Plural PLZTs from the end of the PLZT elements arranged in the main scanning direction within the LZT array chip.
The T element and the remaining PLZT element near the center are configured so that the degree of correction of the exposure driving condition with respect to the deviation between the measured value by the measuring means and the adjustment target value is different.

That is, the inventor of the present invention has found that the position of the band-shaped pattern extending in the sub-scanning direction, which appears in the conventional printing of the image data for adjustment, corresponds to the position of the boundary between the PLZT array chips forming the exposure head. As a result of a detailed examination of the relationship between the PLZT elements and the strip-shaped pattern, a plurality of PLZT elements arranged in the main scanning direction from one end of the PLZT elements are arranged in one PLZT array chip. It has been found that the ultra-light strip-shaped pattern is formed by (a few tens) PLZT elements. That is, although the detailed cause of occurrence is not clear, FIG. 8 schematically shows the relationship between the measured density of the print and the input gradation value.
As shown in (b), a few tens of PLZT elements located at the end of the array of PLZT elements have the characteristics indicated by the one-dot chain line A, and the remaining PLZT elements located near the center are approximately the solid line B. By comparing the two with the characteristics shown in
It has been found that the PLZT element on the end side has a higher rate of change in density with respect to the change in input gradation value than the PLZT element near the center.

Under these circumstances, if the exposure driving conditions for the PLZT elements on the end side are corrected based on the characteristics of the PLZT elements near the center, which occupy the majority, the printing of image data for adjustment is performed. Even when the correction of the exposure driving condition by the above is repeated, the striped pattern C as schematically illustrated as the print result of the single density image in FIG. The deviation from the adjustment target of could not be sufficiently suppressed. Therefore, in consideration of the above-described difference in exposure characteristics between the end side PLZT element and the center-side PLZT element, the measurement value by the measuring means and the adjustment target by the end-side PLZT element and the center-side PLZT element. The degree of correction of the exposure drive condition with respect to the deviation from the value is made different. Therefore, it has become possible to suppress variations in the amount of light emitted from the optical shutter array provided in the exposure head from the adjustment target as much as possible.
In addition, in FIG. 8A, in order to make the drawing easy to see, a pattern C is used.
The density difference is exaggerated in the drawing.

According to the second aspect of the invention, the measuring means comprises an image reading device for measuring the density of the image formed by exposure on the photographic light-sensitive material by the exposure head. There is. That is, the amount of light emitted from each optical shutter of the optical shutter array can be measured by an optical sensor, but by measuring the density of the exposed photographic material with an image reading device, the actual operating state Since it is possible to more accurately measure the amount of light emitted from the optical shutter array, it is possible to more accurately suppress variations in the amount of light emitted from the optical shutter array from the adjustment target.

According to the third aspect of the invention, the PLZT element is arranged in the main scanning direction and a plurality of PLZT array chips integrated in one chip are arranged in the main scanning direction. An exposure head for forming an optical shutter array by elements,
In an image exposure apparatus provided with a measuring means for measuring the amount of light emitted from the LZT element, an exposure head operating condition setting method for setting the exposure driving condition of each PLZT element based on the measurement result of the measuring means is as follows: In one PLZT array chip, a plurality of the PLZT elements are arranged from the end of the PLZT elements arranged in the main scanning direction and the remaining PLZT elements near the center are used to measure the value measured by the measuring means and the adjustment target value. The degree of correction of the exposure driving condition with respect to the deviation is made different.

That is, based on the above-mentioned knowledge about the difference in characteristics between the end side PLZT element and the center side PLZT element in the arrangement of the PLZT elements in one PLZT array chip, the end side PLZT element and the center side PLZT element PLZ
In consideration of the above-mentioned difference in exposure characteristics from the T element, the exposure driving condition is corrected for the deviation between the measured value by the measuring means and the adjustment target value between the end side PLZT element and the central PLZT element. The exposure driving condition is corrected by varying the degree. Therefore, it has become possible to suppress variations in the amount of light emitted from the optical shutter array provided in the exposure head from the adjustment target as much as possible.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the image exposure apparatus of the present invention applied to a photographic print system will be described below with reference to the drawings. The photographic print system DP illustrated in the present embodiment is known as a so-called digital minilab machine, and as shown in FIG.
An image input device IR for inputting image data for producing a photographic print from a developed photographic film, memory card, MO or CD-R, and image data input by the image input device IR is used as a photographic light-sensitive material. The photographic printing paper 2 is exposed and developed by an exposure / developing device EP.

[Schematic Configuration of Image Input Device IR] The image input device IR includes a film scanner 3 for reading frame images of photographic film, a memory reader, an MO drive, and a CD-R, as schematically shown in FIG. An external input / output device 4 including a drive and the like, an image reading device 5 including a flatbed scanner for reading various images,
It comprises a general-purpose small computer system, and is provided with a main controller 6 for controlling the film scanner 3, the external input / output device 4, and the image reading device 5, as well as managing the entire photographic print system DP. The device 6 has a monitor 6a for displaying a simulated image simulating a finished print image and various control information.
And an operation console 6b for performing manual setting of exposure conditions and inputting control information.

[Schematic Configuration of Exposure / Development Device EP]
The developing device EP includes an image exposure device EX, a development processing device PP for developing the photographic paper 2 exposed by the image exposure device EX, and a photographic paper magazine 8 arranged on the upper surface of the housing inside the housing. The photographic printing paper 2 that has been pulled out is conveyed by a large number of conveying rollers 9
And the like, and a printing paper transport system PT for transporting to the development processing device PP.

Outside the housing of the exposure / developing device EP, the photographic paper 2 which has been developed and dried by the development processing device PP.
Sorter 10 for classifying orders by order and outlet 11
A conveyor 12 that conveys the printing paper 2 discharged from the printer to the sorter 10 is provided. Further, a cutter 13 for cutting the long photographic paper 2 pulled out from the photographic paper magazine 8 into a set print size is provided in the middle of the transportation path of the photographic paper transportation system PT.

[Structure of Image Exposure Device EX] The image exposure device EX includes an exposure unit 20 that employs a PLZT optical shutter system and an exposure control device 2 that controls the exposure unit 20.
1 and the main part. Exposure unit 20
As shown in FIG. 3, is a light source 30 and an infrared absorption filter 3 that cuts an infrared component from the light emitted from the light source.
1, a light control filter 32 for adjusting the light passing through the infrared absorption filter 31 to a desired color balance, and a condenser lens 33.
A rotary filter 34 in which red, green, and blue color filters are arranged in the circumferential direction and are driven to rotate by a motor (not shown); and an optical fiber bundle 35 for transmitting the light condensed by the condenser lens 33, A PLZT print head 36 as an exposure head EH connected to the tip of the optical fiber bundle 35 and a shutter control circuit 37 are provided.

In the PLZT print head 36, as shown in FIGS. 1 and 2, ten PLZT array chips 41 in which 512 PLZT elements 40 are arranged in a line and integrated in one chip are arranged, and about 5000 PLZT array chips 41 are arranged. Element 40
The PLZT element 4 is provided with an exposure line consisting of
The arrangement direction of 0s is the main scanning direction of the PLZT print head 36. However, the PLZT element 40 does not form a single row in the main scanning direction, but is schematically shown in the lower drawing of FIG. 1 in which the vicinity of the boundary of the PLZT array chip 41 in the light emission direction view is enlarged. Optical shutter opening 36a
, The even-numbered PLZT elements 40 (shown as “EVEN column” in the figure) and the odd-numbered PLZT elements 40 (shown as “ODD column” in the figure) are sub-scanning orthogonal to the main scanning direction. They are arranged with their positions displaced in the direction. Polarizing plates are arranged on both sides of the optical path of each PLZT element 40 arranged in this way, and a microlens group for forming an image of the transmitted light of each PLZT element on the photographic printing paper 2 is provided. The PLZT print head 36 is
An optical shutter array is formed by arranging each of the LZT elements 40 and an optical shutter configured by these polarizing plates, a microlens group, and the like.

The shutter control circuit 37 for driving each PLZT element 40 has a switch array circuit 43 in which a semiconductor switch 42 for switching whether to apply a power supply voltage to each PLZT element 40 is integrated in one chip, and each switch array circuit 43. A drive circuit 44 that drives the semiconductor switch 42 to open and close is provided. By driving the semiconductor switch 42 to open and close by the drive circuit 44, a pulse voltage is applied to a pair of electrodes formed in each PLZT element 40. When a voltage is applied to the pair of electrodes, the light that has passed through the PLZT element 40 is emitted and enters the light emitting state. When no voltage is applied to the electrodes, the passage of light is blocked and the light emission is stopped. When the driving circuit 44 receives the image data of the image to be printed as the digital density data of each pixel from the exposure control device 21, the pulse voltage having the pulse width corresponding to the data of each pixel is applied to the PLZT element 40 corresponding to the pixel. Each semiconductor switch 42 is driven so as to be applied.

[Adjustment of Image Exposure Device EX] Next, adjustment of the image exposure device EX having the above-described configuration will be described. The adjustment of the image exposure apparatus EX described below is for correcting the variation in the light emission light amount of each optical shutter,
This is performed at the time of factory shipment of the photo print system DP. Here, in the present embodiment, the exposure drive condition is the conversion ratio when converting the received digital image data of each pixel into the pulse width of the pulse voltage applied to the PLZT element 40, and the light emission light amount is the adjustment target value. For the PLZT element 40 of the optical shutter that is larger than the standard value, the conversion ratio is reduced according to the deviation from the standard value, and for the PLZT element 40 of the optical shutter whose light emission amount is smaller than the standard value, The conversion ratio is increased according to the deviation of. The setting of this conversion ratio is changed by the main controller 6.

The adjustment processing of the exposure head EH is performed by the main controller 6
The main controller 6 functions as an operation condition setting unit OC that sets the exposure driving condition of each PLZT element 40. Hereinafter, the exposure head E under the control of the main controller 6
The H adjusting operation will be schematically described with reference to the flowchart of FIG. First, the photographic printing paper 2 is conveyed and moved to the exposure position of the PLZT print head 36, image data for adjusting print production is sent to the exposure control device 21, and the photographic printing paper 2 moving in the sub-scanning direction is exposed to the exposure unit 20. Then, the image of the adjustment print CP is exposed and formed (step # 1). As shown in FIG. 7, the adjustment print CP has a gradation display area 5 that represents a density gradation of achromatic color in a plurality of stages.
1 and an image having position markers 52 for identifying the optical shutters arranged on both sides of the gradation display area 51 are formed on the photographic printing paper 2 by exposure and development processing. The image data of is stored in the main controller 6. The band-shaped regions of the respective density steps forming the gradation display area 51 have a constant density in each of the density steps and extend in the main scanning direction. The adjustment print CP shown in FIG. 7 is formed by exposure with a part of the optical shutters in the main operation direction, and a plurality of adjustment print CPs shown in FIG. 7 are used to adjust the entire width of the exposure head EH. One is made. These plural adjustment prints CP have exactly the same gradation display area 51, and only the display of the position marker 52 is different because the position of the optical shutter is different.

The photographic printing paper 2 on which the image of the adjustment print CP has been exposed is subjected to development processing and drying processing by the development processing apparatus PP, and then discharged from the discharge port 11. The density of the adjustment print CP is read by the image reading device 5 connected to the main control device 6. That is, the image reading device 5
Is the amount of light emitted from the optical shutter, that is, P
It functions as a measuring unit LM that measures the amount of light emitted from the LZT element 40. When the adjustment operator sets a plurality of adjustment prints CP discharged as finished prints in the image reading device 5 and starts the reading operation, the read image data is sequentially taken into the main control device 6, When the input of the image data of the adjustment print CP is completed (step # 2), it is determined whether or not the exposure driving condition needs to be corrected depending on whether or not the read density data is within the set allowable range (step # 2). 3). More specifically, for any density level in the gradation display area 65, an average value (average density value) of density measurement values at a plurality of points in the main scanning direction is obtained, and each is specified from the information of the position marker 52. It is checked for each optical shutter whether the deviation between the density measurement value at the position corresponding to the optical shutter and the average density value is within the setting allowable range. If it is not within the setting allowable range, it is determined that correction is necessary. To do.

When it is determined that the correction is necessary, the average density value is used as the adjustment target value, and the optical shutter (that is, PLZT) is adjusted according to the deviation between the adjustment target value and the measured density data corresponding to the optical shutter requiring the correction. The exposure drive condition of the element 40), that is, the digital image data of each pixel is PL
The conversion ratio for converting the pulse voltage applied to the ZT element 40 into the pulse width is changed. However, the correction of the exposure driving condition is carried out in one PLZT array chip 41 in the arrangement of the PLZT elements 40 in the main scanning direction from the end of 40 PLZT elements 40 (hereinafter, these PLZT elements 40).
The element 40 may be referred to as an “edge processing element”. )
And the remaining PLZT element 40 located closer to the center has different correction methods. Specifically, for the 432 PLZT elements 40 near the center of the chip, the adjustment target value and the correction target are corrected based on the characteristics obtained in advance as general exposure characteristics of the PLZT elements 40. A correction amount is set according to the deviation from the measured density value of the optical shutter, and the exposure driving condition is changed by the correction amount (steps # 4, # 5). On the other hand, for the edge processing element, the adjustment target value and the measured density value of the optical shutter to be corrected are taken into consideration in consideration of having the characteristics described by the one-dot chain line A in FIG. 8B. PL closer to the center according to the deviation from
A value obtained by reducing the correction amount applied to the ZT element 40 by about 10% is set as a correction amount, and the exposure driving condition is changed by the correction amount (steps # 4, # 6).

That is, one PLZT array chip 4
PLZTs arranged in the main scanning direction in 1
A plurality of PLZT elements 40 from the end of the element 40 and the rest of the PLZT elements near the center differ in the degree of correction of the exposure driving condition with respect to the deviation between the measured value by the measuring means LM and the adjustment target value. . The PL requiring correction
When the above correction process is completed for all the ZT elements 40 (step # 7), the adjustment print CP is produced again according to the corrected exposure driving condition (step # 1),
The above process is repeated until the variation in the measured density data of the adjustment print CP falls within the allowable range (step # 3). The driving circuit 44 drives each semiconductor switch 42 by generating a pulse voltage under the exposure driving condition set as described above during the actual operation of the apparatus.

[Manufacturing Operation of Photographic Print] Next, the manufacturing operation of the photographic print by the photographic print system DP having the above-described configuration will be schematically described. When the operator inputs an instruction to make a photographic print for the frame image of the photographic film, the main control device 6 commands the film scanner 3 to read the photographic film, and the film scanner 3 outputs the image data of the photographic film. Are sequentially received and recorded in the built-in memory. On the other hand, when the operator inputs an instruction to make a photographic print for image data recorded on a recording medium such as a memory card, MO or CD-R, the main controller 6 causes the external input / output device 4 to drive the corresponding drive. To read the image data, sequentially receive the image data from the drive and record it in the memory. Furthermore, when the operator inputs an instruction to capture image data from the image reading device 5, the image reading device 5 is instructed to read an image such as a photograph, and the read images are sequentially received and stored in the memory. To record.

Based on the image data input as described above, the main control device 6 sends a simulated image, which will be obtained when a print is made from the image data, to an image processing circuit (not shown). And calculate it,
It is displayed on the monitor 6a. The operator uses this monitor 6
The simulated image on a is observed, and if an appropriate image is not obtained, a correction input operation of the exposure condition is performed from the console 6b. The image processing circuit of the main controller 6 generates exposure image data for each of red, green, and blue under preset calculation conditions in accordance with the input image data and its correction input.

The exposure image data is sent to the exposure control device 21 of the exposure / developing device EP and stored in the memory provided in the exposure control device 21. Exposure control device 21
Detects that the front end of the photographic paper 2 has been conveyed to a predetermined exposure start position based on the conveyance information of the photographic paper 2 obtained from the photographic paper conveyance system PT, the exposure processing speed of the exposure unit 20 is determined. The image data for exposure is sequentially transmitted to the exposure unit 20 at a corresponding speed. Exposure unit 20
Activates the optical shutters of the PLZT print head 36 based on the received image data for exposure to print the photographic paper 2
Form a latent image of the printed image on. The photographic printing paper 2 that has been subjected to the exposure processing by the exposure unit 20 is conveyed to the development processing device PP by the photographic printing paper conveyance system PT, and is developed by being sequentially passed through the respective development processing tanks.
Is further dried and then discharged from the outlet 11 to the conveyor 1
It is discharged to the upper part of the table 2 and sorted by the sorter 10 for each order.

[Other Embodiments] Other embodiments of the present invention will be listed below. (1) In the above embodiment, the optical shutter, that is, the PLZ
Although the image reading device 5 configured by a flatbed scanner is illustrated as the measuring unit LM for measuring the light emission light amount of the T element 40, for example, the light emission light amount is directly measured by an optical sensor. The measuring means LM may be configured. (2) In the above-described embodiment, the adjustment print CP shown in FIG. 7 is also illustrated, but the image of the adjustment print CP is, for example, an image having a constant density on the entire surface. Etc., various changes are possible.

(3) In the above embodiment, the PLZT elements 40 are arranged in the main scanning direction while being displaced in the ODD row and the EVEN row to form an exposure line for one row of pixels. However, a single element row has a pixel 1
An exposure line for columns may be configured, or an exposure line for one pixel may be configured in more columns. (4) In the above-described embodiment, the exposure head EH includes the pixel 1
Although the case where the exposure lines for the columns are provided is illustrated, the exposure lines for the pixels for a plurality of columns may be provided. (5) In the above-described embodiment, the number of PLZT elements 40 and the number of edge processing elements in one chip are specifically illustrated. However, these values depend on the PLZT array chip 41 used. Correspondingly, it is changed appropriately.

[0027]

According to the structure of the first aspect, the PL
In consideration of the difference in exposure characteristics between the end side PLZT element and the center-side PLZT element in the ZT array chip, the end-side PLZT element and the center-side PLZT element have a measured value by the measuring means and an adjustment target value. By varying the degree of correction of the exposure driving condition with respect to the deviation of (1), it has become possible to suppress variations from the adjustment target of the light emission light amount of the optical shutter array provided in the exposure head as much as possible.

Further, according to the above-mentioned structure of claim 2, the amount of light emitted from each optical shutter of the optical shutter array is measured.
It is possible to measure with an optical sensor, but by measuring the density of the exposed photographic material with an image reading device, it is possible to more accurately measure the light output light amount in a state close to the actual operating state. It is possible to more accurately suppress variations in the amount of light emitted from the shutter array. or,
According to the configuration of claim 3, in consideration of the difference in the exposure characteristics between the PLZT element on the end side and the PLZT element near the center in the PLZT array chip, the PLZT element on the end side and the PLZT element near the center are considered. By varying the degree of correction of the exposure drive condition with respect to the deviation between the measurement value and the adjustment target value by the measuring means, the variation of the light emission light amount of the optical shutter array provided in the exposure head from the adjustment target can be suppressed. The exposure drive condition of the exposure head can be set so that it can be suppressed as much as possible.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an exposure head according to an embodiment of the present invention.

FIG. 2 is a block configuration diagram of an exposure head according to an embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of an exposure unit according to an embodiment of the present invention.

FIG. 4 is a schematic block configuration diagram of a photographic print system according to an embodiment of the present invention.

FIG. 5 is an external perspective view of the photographic print system according to the embodiment of the present invention.

FIG. 6 is a flowchart according to the embodiment of the present invention.

FIG. 7 is an explanatory diagram of an adjustment print according to the embodiment of the present invention.

FIG. 8A is a diagram illustrating a state of occurrence of uneven density. (B) Schematic diagram showing the input / output characteristics of the optical shutter

[Explanation of symbols]

EH exposure head LM measuring means OC operating condition setting means 5 Image reader 40 PLZT element 41 PLZT array chip

Claims (3)

[Claims] 1. The PLZT is provided by arranging a plurality of PLZT array chips in which PLZT elements are arranged in the main scanning direction and integrated in one chip in a state of being arranged in the main scanning direction.
An exposure head that forms an optical shutter array with elements,
Measuring means for measuring the amount of light emitted from the PLZT element;
An image exposure apparatus provided with operating condition setting means for setting an exposure driving condition of each PLZT element based on the measurement result, wherein the operating condition setting means is in one PLZT array chip in the main scanning direction. PLZ arranged in
A plurality of PLZT elements from the end of the T element and the remaining PLZT elements near the center are configured so that the degree of correction of the exposure driving condition with respect to the deviation between the measured value by the measuring means and the adjustment target value is different. Image exposure device. 2. The image exposure apparatus according to claim 1, wherein the measuring means comprises an image reading apparatus that measures the density of an image formed by exposure on the photographic photosensitive material by the exposure head. 3. The PLZT is provided by arranging a plurality of PLZT array chips in which PLZT elements are arranged in the main scanning direction and integrated in one chip in a state of being arranged in the main scanning direction.
An exposure head that forms an optical shutter array with elements,
In an image exposure apparatus provided with a measuring means for measuring the amount of light emitted from the PLZT element, there is provided a method for setting an operating condition of an exposure head for setting an exposure driving condition of each PLZT element based on a measurement result of the measuring means. Then, in one PLZT array chip, a plurality of PLZT elements from the end of the PLZT elements arranged in the main scanning direction and the remaining PLZT elements near the center are measured by the measuring means and adjustment targets. A method for setting an operating condition of an exposure head, wherein the degree of correction of the exposure driving condition with respect to the deviation from the value is different.