WO2006006474A1

WO2006006474A1 - Exposure system

Info

Publication number: WO2006006474A1
Application number: PCT/JP2005/012529
Authority: WO
Inventors: Kazunobu Ohkubo
Original assignee: Fuji Photo Film Co., Ltd.
Priority date: 2004-07-13
Filing date: 2005-06-30
Publication date: 2006-01-19
Also published as: JP2006026954A

Abstract

An exposure system, which controls the power supply voltage of a circuit for driving a light emitting element to a low level to thereby reduce a system cost, uses a light emitting head (10) that positions a light emitting element row (11R), for emitting a light of a higher-coloring-efficiency color when color paper (1) is exposed and colored, farther from the center (C) in the width direction of a lens array unit (20) than a light emitting element row (11B) for emitting a light of a color lower in coloring efficiency than the first light of color and positions a light emitting element row (11G), for emitting a light of a higher-coloring-efficiency color when color paper (1) is exposed and colored, farther from the center (C) in the width direction of a lens array unit (20) than a light emitting element row (11R) for emitting a light of a color lower in coloring efficiency than the first light of color, and images, on the color paper (1), lights emitted from light emitting elements (Q) constituting respective light emitting element rows (11) via the lens array unit (20) consisting of the above many lenses (L) to expose the color paper (1) to light.

Description

Description Exposure Equipment Technical Field

The present invention relates to an exposure apparatus, and more particularly to an exposure apparatus that exposes a photosensitive material family by passing each light emitted from a large number of light emitters arranged in a light emitting head through a lens array section. Background art

Conventionally, exposure apparatuses that create hard copies of color images are known. The photosensitive material for hard copy used in such an apparatus is a color photographic paper, a color silver salt film or the like, and the exposure part for exposing the photosensitive material is each color of red, green, and blue. It is known that it is composed of a number of light emitters that emit each of the light beams and an imaging optical system that forms an erecting equal-magnification image of the light emitted from the light emitters on a photosensitive material. ing. In addition, there is known an imaging optical system using a lens array in which a large number of gradient index lenses are arranged (Japanese Patent Laid-Open Nos. 7-2 2 6 49 and 2 0 0 1). — See 1 6 7 8 7 4).

Since the exposure apparatus can increase the amount of light emitted from the light emitter in accordance with the drive voltage for driving the light emitter, the power supply voltage of each drive circuit for driving the light emitter The photosensitive material can be colored at the maximum density by setting it to a voltage higher than a predetermined voltage at which the material can be colored at the maximum density. Further, the driving voltage of each light emitter that emits the light of each color required to develop the color of the photosensitive material at the maximum density is different for each color. Therefore, the power supply voltage is determined according to the highest voltage among the drive voltages required for each light emitter that emits light of each color and capable of developing the photosensitive material at the maximum density.

Incidentally, there is a demand for a reduction in apparatus cost for the above-described exposure apparatus. Lowering the power supply voltage of the drive circuit that drives the light body leads to a reduction in apparatus cost, so that each light emitter can be driven so that the amount of light of each color that causes the photosensitive material family to develop color at the maximum density can be obtained. There is a demand to keep the power supply voltage low.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an exposure apparatus that can suppress the power supply voltage of a drive circuit that drives a light emitter, thereby reducing the apparatus cost. Is. Disclosure of the invention

The exposure apparatus of the present invention has a plurality of light emitter rows in which a large number of light emitters that emit light of the same color are arranged in one row, and each light emitter row emits light of a different color. And imaging each light emitted from the light emitter on a photosensitive material,

An exposure apparatus having a lens array unit composed of a large number of lenses arranged in one direction, and a light emitting head that emits light of a color with high coloring efficiency when the photosensitive material is exposed to color. The light emitter array that emits light with a color generation efficiency lower than that of the light of this color is positioned closer to the center of the lens array in the width direction than the array. It is a feature.

The color development efficiency refers to the color produced when light emitted from a light emitter driven by applying a predetermined driving voltage is irradiated and exposed to a photosensitive material without passing through the lens array portion, and the photosensitive material is colored. Is a value obtained by dividing the rate (coloring rate will be described later) by the above-mentioned predetermined drive voltage. Light emitted from the light emitter is irradiated to the photosensitive material without passing through the lens array portion, and is exposed. This means the color development rate per unit voltage when the photosensitive material is colored. That is, “coloring efficiency = coloring rate / driving voltage”.

The color development ratio means the ratio of the density level obtained when the light-sensitive material is actually colored to the maximum density level obtained when the light-sensitive material is colored. That is, “color development rate = density level obtained when the photosensitive material is actually developed / maximum density level obtained when the photosensitive material is developed”. The above-mentioned “positioning the illuminant row closer to the center in the width direction of the lens array portion J means that the central axis of the luminous flux of the light emitted from the illuminant constituting the illuminant row is the other illuminant row. This means that the light emitter row is positioned so as to pass closer to the center of the lens array portion in the width direction than the central axis of the luminous flux of the light emitted from the light emitter that constitutes .

The light emitting head includes: a light emitter row that emits light of a color with the lowest coloring efficiency among the plurality of light emitter rows; and another light emitter row that is different from the light emitter row. In relation to any one of the light emitter rows, a light emitter row that emits light of a color with low color development efficiency compared to light of this color than a light emitter row that emits light of a color with high color development efficiency. Can be positioned closer to the center of the lens array portion in the width direction.

The light emitting head has a light of this color as compared with the light emitter row that emits light having a high coloration efficiency for any two light emitter rows selected from the plurality of light emitter rows. The light emitter array that emits light having a color development efficiency lower than that of the lens array can be positioned closer to the center in the width direction of the lens array section. That is, the plurality of light emitter rows can be positioned closer to the center in the width direction of the lens array portion in the order of poor coloring efficiency.

The different colors may be red, green, and blue.

Each lens constituting the lens array unit can be a gradient index lens.

The lens array part may be a microlens array.

The microphone mouth lens array is one in which a large number of microphone mouth lenses are arranged on one substrate, and this substrate and a number of microphone mouth lenses are formed in a body.

The light emitter may be composed of an organic EL element, an inorganic EL element, or an LED element.

The present inventor has said that the coloring efficiency is different for each of the colors, The light utilization efficiency (light utilization efficiency will be described later) differs depending on the location of the light emitted from the light emitter array through the lens array, and the above photosensitive material is colored at the maximum density. The drive voltage of each light emitter row is different for each color, and the power supply voltage is determined according to the highest voltage among the drive voltages determined for each color (that is, the drive circuit of each light emitter row). Each power source voltage can be kept low while enabling each light emitter row to be driven so as to obtain the amount of light of each color that develops the photosensitive material at the maximum density. This is the finding of the arrangement of the light emitter rows.

The light utilization efficiency is the ratio of the light amount before passing through the lens array portion of the light to the light amount after passing through the lens array portion.

According to the exposure apparatus of the present invention, the color of the light emitting efficiency is lower than that of the light emitter array that emits light of a color with high color development efficiency when the photosensitive material is exposed to color. Since the light emitter array that emits light is positioned closer to the center of the lens array in the width direction, the power supply voltage for driving the light emitter can be kept low, thereby reducing the equipment cost. Can be reduced. The reason will be described below. For example, two illuminant rows that emit light of different colors in the illuminant row (here, the illuminant row that emits light of a color with low coloring efficiency is referred to as a low-efficiency illuminant row, and Let us consider a light emitter array that emits light of a color with a higher coloring efficiency than the color of light emitted by the low efficiency light emitter array.

With respect to the above-described high-efficiency illuminant array and low-efficiency illuminant array, the driving voltage of the illuminant for coloring the photosensitive material at a coloration rate of 100% without passing light through the lens array section is high-efficiency The low-efficiency luminous body row is higher than the body row.

On the other hand, the amount of exposure light when exposing the photosensitive material by passing the same color and the same amount of light emitted from the illuminant array through the lens array section, passes this light through the optical path with high light utilization efficiency in the lens array section. However, it is more than the case where the light passes through an optical path having lower light use efficiency than the above optical path. That is, the range of the light beam that is incident on the lens array unit and kicked by the lens array unit when passing through the lens array unit is Since the optical axis of the light beam passing through the zoom section decreases as the distance from the center in the width direction of the lens array section decreases, the light passing through the optical path closer to the center in the width direction of the lens array section is more in comparison to this optical path. Therefore, there is less light loss than passing light through an optical path farther away from the center in the width direction. Therefore, the driving voltage of the light emitter array required for coloring the photosensitive material by 100% depends on the center in the width direction of the lens array portion where the loss of light amount is small. It can be lowered by passing it closer.

Furthermore, the power supply voltage is set according to the highest voltage among the drive voltages (each maximum drive voltage) of each light emitter row for causing the lens array part to emit light with a color development rate of 100%. Determined.

As a result of the above, light emitted from a low-efficiency illuminant array having a higher driving voltage for coloring the photosensitive material at a coloring rate of 100% is used to cause the photosensitive material to develop a color at a coloring rate of 100%. The light emitted from the light emitters of the low-efficiency light emitter row is made to pass through the light-sensitive material with a color development rate of 10 0, rather than passing through an optical path that is further away from the center of the lens array portion in the width direction. Driving the optical path closer to the width direction from the center of the lens array part where the driving voltage for color development at 0% is lower is the above for driving both the high efficiency light emitter array and the low efficiency light emitter array. The power supply voltage can be kept low.

In the above description, two light emitter rows that emit light of different colors have been considered. For example, a light emitter row that emits light of a color with the lowest coloring efficiency among a plurality of light emitter rows, and The above consideration is applied to any one of the plurality of light emitter rows different from the light emitter row, or two light emitters selectable from the plurality of light emitter rows By applying the above considerations for all combinations of columns, it is possible to consider more than two emitter columns that emit light of different colors. Brief Description of Drawings

FIG. 1 is a perspective view showing a schematic configuration of an exposure apparatus according to an embodiment of the present invention.

Fig. 2 is a side view of the exposure device as seen from the direction of arrow X in Fig. 1.

Fig. 3 A and B are views of the emitter array and lens array as seen from above.

Fig. 4 is a diagram for explaining the coloring efficiency when the lens array portion is removed from the exposure apparatus. Fig. 5 A and B are diagrams showing various examples of the phosphors included in the light emitting head. Showing the schematic configuration of the exposure apparatus of

7A and 7B are diagrams showing an example of the arrangement of the light emitter rows with respect to the lens array portion in the exposure apparatus of the present invention.

FIGS. 8A and B are diagrams showing an example of the arrangement of the light emitter rows with respect to the lens array portion in the exposure apparatus of the present invention

Figure 9A shows the spectral sensitivity of the photosensitive material, Figure 9B shows the normalized power spectrum, and Figure 9C shows the relative luminous sensitivity

FIG. 10 is a diagram showing the relationship between the driving voltage of a light emitter and the luminance of light emitted from this light emitter. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described. FIG. 1 is a perspective view showing a schematic configuration of an exposure apparatus according to an embodiment of the present invention, FIG. 2 is a side view of the exposure apparatus seen from the direction of arrow X in FIG. 1, and FIG. Fig. 3B is a top view of the lens array, and Fig. 3B shows the position of the light passing through the lens array on the horizontal axis and the position in the Y direction shown in Fig. 1 on the vertical axis. Fig. 4 is a diagram illustrating the relationship with the utilization efficiency, Fig. 4 is a diagram for explaining the color development efficiency, and is a diagram in which the lens array unit is removed from the above exposure apparatus, and Figs. 5A and 5B are diagrams of the illuminant constituting the light emitting head. It is a figure which shows various aspects.

The illustrated exposure apparatus 10 1 of the present invention has a light emitter row 1 1 R in which a large number of light emitters Q r that emit red light of the same color are arranged in one row, and green that is light of the same color. The light emitter array 1 1 G, which has a large number of light emitters Q g that emit light of the same color, and the same color light A light emitting head 10 having a light emitter row 1 1 B (collectively referred to as a light emitter row 1 1) in which a large number of light emitters Q b emitting blue light are arranged in one row, each light emission Body rows 1 1 R, 1 1 G, 1 1 B are different colors, emitting heads emitting red, green, and blue light 1 0 and the above emitters Q r, Q g, Q b (Collectively also referred to as the illuminant Q). Each lens emitted from the lens is formed on a color paper 1 that is a photosensitive material. It has.

The exposure apparatus 1 0 1 further includes drive circuits 30 R, 3 0 G, 3 0 B (collectively referred to as drive circuits 3 0) that drive each of the light emitter rows 1 1, and One drive power source 35 for the drive circuit 30 is provided.

The color paper 1 is linearly exposed in the main scanning direction (arrow X direction in the figure), which is the direction in which each light emitter row extends by the above exposure apparatus, while in the sub-scanning direction (arrow Y direction in the figure). It is transported and exposed in two dimensions.

Each of the light emitters Q can be composed of an organic EL element, an inorganic EL element, an LED element, or the like.

The lens array unit 20 may be a microlens array, or each lens L of the lens array unit 20 may be a gradient index lens. The lens array unit 20 forms an erecting equal-magnification image of the illuminant Q, that is, an erecting equal-magnification image of light emitted from the illuminant Q on the color paper 1. . The light-emitting head 10 has a color development efficiency lower than that of the light emitter array that emits light having a high color development efficiency when the color paper 1 is exposed to color. The light emitter array that emits light is positioned closer to the center of the lens array section 20 in the width direction. Therefore, the emitter array 1 1 R that emits red light with a lower coloring efficiency than the light emitter array G that emits green light with a higher coloring efficiency is used in the lens array section. Compared to the light emitter row R, which is positioned closer to the center in the width direction of 20 and emits red light with high color development efficiency, blue light with lower color development efficiency than this red light is emitted. The emitted light emitter row 11 B is positioned closer to the center of the lens array portion 20 in the width direction. In the combination of the exposure apparatus 10 1 and the color paper 1, the color having the highest color development efficiency is green, and the color development efficiency decreases in the order of red and blue. That is, the green color development efficiency E g> the red color development efficiency E r> the blue color development efficiency E b.

Further, each light emitter row 1 1 R, 1 1 G, 1 1 B arranged in the light emitting head 10 is arranged in parallel to the incident surface 20 N of the lens array section 20, and the lens A light emitter array 11 B that emits blue light is arranged at the center C in the width direction of the array section 20 (in the arrow Y direction in the figure). As shown in Fig. 2 and Fig. 3A, the emitter row 1 1 R that emits red light, which has higher coloring efficiency than the blue color, and the emitter row 1 1 G that emits green light are blue. The light emitter row 1 1 B that emits light is arranged on both sides, and the light emitter row 1 1 R is arranged closer to the center C than the light emitter row 1 1 G in the width direction. The body row 11 B is disposed closer to the center C in the width direction than the light emitter row 11 R.

More specifically, the light emitter row 1 1 B is located at the center of the lens array unit 20 in the width direction, that is, at a position separated from the center C by the distance L 1 = 0 in the width direction. The light emitter row 1 1 R is arranged at a position K 2 away from the center C in the width direction by a distance L 2, and the light emitter row 1 1 G is located away from the center C in the width direction by a distance L 3 Located at K3, the distance is 3> distance L2> distance L1. Since the distance 1 = 0, the illustration of the distance L 1 in FIG. 2 and FIG. 3A is omitted.

That is, in the exposure apparatus 10 0 1, the green color development efficiency E g> the red color development efficiency E r> the blue color development efficiency E b, and the position of each light emitter row 1 1 with respect to the lens array unit 20 is The distance is set so that 1 <distance L 2 <distance L 3. As shown in FIG. 4, each light emitter row 1 1 R, 1 1 G, 1 IB was driven with the same voltage and emitted from each light emitter row 1 1 R, 1 1 G, 1 1 B. When the color paper 1 is irradiated with red, green, and blue light on the color paper 1 without passing through the lens array 20 and the color paper 1 is exposed and developed, the color development rate is green light. The color developed by exposure is highest, and decreases in the order of red and blue. That is, under the above conditions, the green color development rate H g> the red color development rate H r> the blue color development rate H b. As shown in FIG. 3B, the lens array unit 20 is configured so that the specific axis of the light beam passing through the lens array unit 20 passes this center C in the width direction of the lens array unit 20. The light utilization efficiency δ relating to the light of the light is the highest (that is, the attenuation of the amount of light passing through the lens array 20 is the smallest), and the central axis of the light beam of the specific light is from the center C to the width direction. As the distance increases, the light utilization efficiency δ for this specific light decreases (the attenuation of the amount of light passing through the lens array section 20 increases).

Next, the relationship among the voltage of the drive power supply 35, the color development efficiency for each color, and the arrangement of the light emitter rows 11 with respect to the lens array section 20 will be described in detail.

As shown in FIG. 2 above, this exposure apparatus 1 0 1 is such that the drive power supply 3 5 supplies a voltage of 10 V, and each drive circuit 3 0 R, 3 0 G, 3 0 B When the light emitter row 1 1 R, 1 1 G, 1 1 B is driven at the same drive voltage of 10 V and color paper 1 is exposed, the color development rate of each color on this color paper 1 is Each is set to 1 (1 0 0%).

Here, the light utilization efficiency δ when the blue light emitted from the light emitter array 1 1 B passes through the center C in the width direction of the lens array section 20 is 0.9 (9 0%), Light emitter array 1 1 Red light emitted from R passes through position Κ 2 away from center C in the width direction of lens array section 20 Light utilization efficiency 5 is 0.8 (8 0%) The green light emitted from the light emitter array 1 1 G passes through a position Κ 3 further away from the center C in the width direction of the lens array section 20 compared to Κ 2 above. The utilization efficiency δ is 0.7 (70%).

In addition, the red, green, and blue light emitted from each of the light emitter rows 1 1 R, 1 1 G, and 1 1 B is irradiated onto the color paper 1 without passing through the lens array section 20. The color development rate per unit voltage (IV) when the color paper 1 is exposed and colored is the highest color development rate H g when exposed to green light (0.1 4 3) 1 4. 3 %, Color development rate H r when exposed to red light is the next highest (0.1 2 5) 1 2.5%, color development rate H b when exposed to blue light is the lowest (0.1) 1 1) 1 1. 1% (Fig. 4 See).

Note that the above color development rates are the red, green, and red light emitted from each light emitter row 1 1 R, 1 1 G, 1 1 B by driving each light emitter row 1 1 R, 1 1 G, 1 IB. Since each blue light is irradiated on the color paper 1 without passing through the lens array section 20 and this color paper 1 is exposed and colored, it is a value per unit voltage (IV). This value matches the color development efficiency of each color. That is, in the above-described apparatus configuration, the green color development efficiency E g = 0.1 4 3> red color development efficiency E r = 0.1 2 5> blue color development efficiency E b = 0.1 1 1 1

In the exposure apparatus 10 0 1 of the present invention whose specifications are determined as described above, the light emitter rows 1 1 R, 1 1 G, and 1 1 B are driven with the same drive voltage 10 (V) to obtain a color page. The case of exposing part 1 will be described with reference to FIG.

When the illuminant string 1 1 R is driven at a drive voltage of 10 (V), the light intensity per unit area emitted from the illuminant Q r of the illuminant string 1 1 R is 8 0 (1 m s), and the amount of light when the central axis of the light beam of the light passes through the position K 2 of the lens array unit 20 and is emitted from the lens array unit 20 is 8 0 X 0.8 (light Utilization efficiency) = 6 4 (1 m · s), and light with this light intensity is imaged on the color paper 1, and this power paper 1 is exposed and colored. The coloring rate at this time is 1 (1 0 0%).

In addition, when the light emitter row 1 1 B is driven at a driving voltage of 10 (V), the light amount per unit area emitted from the light emitter Q b of the light emitter row 1 1 B is 9 0 (1 m ■ s), and the amount of light when the central axis of the light beam of this light passes through the position C of the lens array unit 20 and is emitted from the lens array unit 20 is 9 0 X 0.9 (light Utilization efficiency) = 8 1 (1 m · s), and light with this light intensity is imaged on color paper 1 and the power paper is exposed and colored. The coloring rate at this time is 1 (1 0 0%) as described above.

In addition, when the light emitter array 1 1 G is driven at a driving voltage of 10 (V), the light intensity per unit area emitted from the light emitter Q g of the light emitter array 1 1 G is 7 0 (1 m · S) Therefore, the amount of light when the central axis of the luminous flux of this light passes through the position K 3 of the lens array section 20 and is emitted from the lens array section 20 is 9 0 X 0.7 (light utilization efficiency) = 4 9 (1 m · s), and light with this light intensity is imaged on color paper 1 and the color paper is exposed and colored. The coloring rate at this time is 1 (1 0 0%) as described above.

When the light emitter rows 1 1 R, 1 1 B, and 1 1 G are driven at the same drive voltage 1 0 (V) in this way, the amount of light that exposes the color paper 1 is that of red light 6 4 (1 m · s), blue light is 8 1 (1 m · s), green light is 49 (1 m · s), and the color development rate of color paper 1 exposed with the light of each color H r, H b Hg is 1 (1 0 0%).

As shown in FIG. 5A, the light emitter Q of the light emitting head 10 is a light emitting element 15 that emits red, green, and blue light, respectively, or as shown in FIG. 5B. A light emitting element 16 that emits white light, and a color filter 17 for each color that emits red, green, and blue light through the light emitted from the light emitting element 16. can do.

The exposure apparatus 101 according to the present invention has a color development efficiency lower than that of the light emitter array that emits light having a high color development efficiency when the photosensitive material is exposed to color. The light emitter array that emits the light is positioned closer to the center of the lens array portion in the width direction, but a conventional exposure apparatus that is not set in this way, more specifically, the light emitter array A conventional exposure apparatus having a light emitting head in which the position where 1 1 B is disposed and the position where light emitter row 1 1 G is disposed will be described. FIG. 6 is a view showing the schematic arrangement of a conventional exposure apparatus.

Hereinafter, regarding the conventional exposure apparatus 201, the relationship among the voltage of the drive power supply, the color development efficiency for each color, and the arrangement of each light emitter row with respect to the lens array section will be described. The conventional exposure apparatus 201 has the same arrangement as that of the exposure apparatus 1001, except that the arrangement of the light emitter rows in the exposure apparatus 101 of the present invention is changed. Components having the same functions as the device 1 0 1 have the same reference numerals. The description is omitted.

In the above exposure apparatus 20 0 1, the central axis of the light beam emitted from the light emitter Q g constituting the light emitter row 1 1 G passes through the center C in the width direction of the lens array portion 20, and the light emitter row 1 1 Luminous body constituting R. Luminescent light constituting the illuminating element array 11 B through the center axis of the light beam emitted from the r passing through the position K 2 away from the center C of the lens array section 20 in the width direction. The central axis of the light beam emitted from the body Q b passes through the position K 3 further away from the center C of the lens array portion 20 in the width direction. More specifically, the light emitter row 1 1 G is located at the center C in the width direction of the lens array unit 20, that is, at a position away from the center C by the distance L 1 = 0 in the width direction. The light emitter row 1 1 R is disposed at a position K 2 away from the center by a distance L 2 in the width direction, and the light emitter row 1 1 B is separated from the center C by a distance L 3 in the width direction. The distance L 3> distance L 2> distance L 1 is set at the position indicated by the position K 3.

The respective light emitter rows 11 R, 11 G, and 1 IB arranged as described above are driven with the same drive voltage 10 (V).

When the light emitter array 1 1 R is driven at a driving voltage of 10 (V), the light intensity per unit area of the light emitted from the light emitter Q r of the light emitter array 1 1 R is the same as above. (1 m · s), and the amount of light when the central axis of the light beam of this light passes through the position K 2 of the lens array unit 20 and exits from the lens array unit 20 is the same as above. 0 X 0.8 (light utilization efficiency) = 6 4 (1 m · s). When the light having this amount of light is imaged on the color paper 1 and the color paper 1 is exposed and colored, the coloration rate is 1 (100%) as described above.

In addition, when the light emitter array 1 1 G is driven at a driving voltage of 10 (V), the light intensity per unit area of the light emitted from the light emitter Q g of the light emitter array 1 1 G is the same as above. 0 (1 m-s), and the amount of light when the central axis of the luminous flux of this light passes through the center C of the lens array section 20 and is emitted from the lens array section 20 is 7 0 X 0.9. (Utilization efficiency of light) = 6 3 (1 m · s). When the light having this amount of light is imaged on the color paper 1 and the color paper 1 is exposed and colored, the color development rate of the exposure apparatus of the present invention is as follows. Unlike the case of the case, it becomes 1.28 (1 2 8%). In other words, the amount of light required to develop color paper 1 with green light at a coloration rate of 100% is 4 9 (1 m · s) (see Fig. 2), so the above light amount 6 3 (1 m · s) is The amount of light that causes color paper 1 to develop at a coloration rate of 100% or more (1.28 = 6 3 (1 m · s) / 9 (1 m · s)). The color development rate is a calculated value, and it does not mean that color paper 1 is actually colored at a color development rate of 100% or more.

In addition, when the light emitter row 1 1 B is driven at a driving voltage of 10 (V), the light amount per unit area of the light emitted from the light emitter Q b of the light emitter row 1 1 B is the same as the above. 0 (1 m · s), and the amount of light when the central axis of the light beam of the light passes through the position K 3 of the lens array unit 20 and is emitted from the lens array unit 20 is 9 0 X 0 7 (Light utilization efficiency) = 6 3 (1 m · s). Unlike the exposure apparatus of the present invention, the color development rate when light having this light intensity is imaged on the color paper 1 and the color paper 1 is exposed and colored is 0.7.7 7 (7 7. 7%). In other words, the amount of light required to develop color with a blue light at a coloring rate of 100% is 8 1 (1 m · s) (see Fig. 2). ) Color paper 1 cannot be developed with a coloration rate of 100% (0.77 7 = 6 3 (1 m · s) / 8 2 (1 m · s))

When each light emitter array 11 is driven with the same driving voltage 10 (V) as described above, the amount of light that exposes the color paper 1 is 6 4 (1 m · s) for red light and green light. Is 6 3 (1 m · s), blue light is 63 (1 m · s), and the color paper 1 color development ratio H r by exposure with red light is 1 (1 0 0%), green The color development rate Hg by exposure with light is 1.27 (1 27%), and the color development rate Hb by exposure with blue light is 0.77 7 (77.7%).

In such a case, the voltage for driving the light emitter row 1 1 B is set to 1 0 (in order to cause the color paper to develop with a color development rate of 100% by emitting blue light from the light emitter row 1 1 B. V) Must be at least. More specifically, the amount of light required to develop color paper 1 with blue light at a coloration rate of 100% is 8 1 (1 m · s). The drive voltage is 1 2.9 V = 10 (V) X (81 (1 m · s) / 6 3 (1 m • s)). Therefore, in the conventional exposure apparatus 20 0 1, the voltage of the drive power supply 35 is set to a voltage (12.9 V or higher) higher than the voltage (1 0 V) of the drive power supply of the exposure apparatus 10 1 of the present invention. Must be set.

As described above, the exposure apparatus 10 1 of the present invention described above is different from the conventional exposure apparatus 10 2 in that the coloring efficiency is obtained for any two light emitter rows selected from a plurality of light emitter rows. Compared to the center of the lens array section in the width direction, the emitter array that emits light of a color with a lower coloring efficiency than the light emitter array that emits light of a higher color. Equipped with a light emitting head that is located close to each other, so that each light emitter can be driven so that the amount of light that can be generated at the maximum density of the color balance can be obtained, while keeping the power supply voltage low. be able to.

Hereinafter, various examples of the arrangement of the respective light emitter rows with respect to the lens array portion in the exposure apparatus of the present invention will be described. FIG. 7A is a view showing an example of the arrangement of the light emitter rows with respect to the lens array portion in the exposure apparatus of the present invention, and FIG. 7B is a coordinate on the horizontal axis indicating the Y-direction position and the vertical axis indicating the light use efficiency. FIG. 8A is a diagram showing the relationship between the position of light passing through the lens array section and the light use efficiency, FIG. 8A is a diagram showing an example of the arrangement of the light emitter rows with respect to the lens array section in the exposure apparatus of the present invention, and FIG. FIG. 4 is a diagram showing the relationship between the position of light passing through the lens array part and the light utilization efficiency on the coordinates indicating the Y-direction position on the horizontal axis and the light utilization efficiency on the vertical axis. Note that various examples of the arrangement of the light emitter rows with respect to the lens array section are obtained by changing the arrangement of the light emitter rows in the exposure apparatus 1001, and other specifications are the same as those of the exposure apparatus 1001. Therefore, constituent elements having a common function are denoted by the same reference numerals and description thereof is omitted.

As shown in Fig. 7, when the color development efficiency of green and red is equal, and the color development efficiency of blue is lower than the green and red color development efficiency, that is, green color development efficiency E g = color development efficiency of red E r> blue In the case of the color development efficiency E b, the light emitter array 11 B that emits blue light is arranged at the center C in the width direction of the lens array section 20, and the center C is on both sides of the center C and the center C is the above. At positions 1 1 K and 1 2 mm away from each other by the same distance in the width direction, Each of the light body row 1 1 R and the light body row 1 1 G is arranged. This arrangement is higher than that of the light emitter row 1 1 R and the light emitter row 1 1 G, which emits light of a color with high coloration efficiency when the color paper 1 is exposed and colored. The light emitter row 1 1 B that emits light of a color with low color development efficiency is positioned closer to the center C in the width direction of the lens array portion 20, that is, among the plurality of light emitter rows. A light emitter row that emits light of a color with the lowest color development efficiency, and any one of the plurality of light emitter rows that are different from the light emitter row. The light emitter array that emits light with a color development efficiency lower than that of the light emitter array that emits light of the color is positioned closer to the center of the lens array in the width direction. As described above, the amount of light that causes color paper 1 to develop color at the maximum density Thus, it is possible to obtain an effect of suppressing the power supply voltage while enabling driving of each light emitter.

Also, as shown in Fig. 8, when the blue and red color development efficiency is equal and the green color development efficiency is higher than the blue and red color development efficiency, that is, blue color development efficiency E g = red color development efficiency E r <In the case of the green color development efficiency Eb, at positions 2 1 K and 2 2 that are near both sides of the center C in the width direction of the lens array section 20 and are separated from the center C by the same distance in the width direction. Each of the light emitter row 1 1 Β and the light emitter row 1 1 R is disposed, and the light emitter is located at a position 2 3 離れ away from the center C in the width direction as compared with the positions 2 1 Κ and 2 2 上記. Row 1 Place 1 G. This arrangement allows light with a color development efficiency lower than that of the light emitter array 1 1 G, which emits light with a high color development efficiency when color paper 1 is exposed to color. Are arranged closer to the center C in the width direction of the lens array portion 20, that is, the plurality of light emitter rows of the light emitter row 1 1 R and the light emitter row 1 1 B are emitted. A light emitter row that emits light of a color with the lowest color development efficiency, and any one of the plurality of light emitter rows different from the light emitter row. A light emitter array that emits light with a color development efficiency lower than that of light of this color is closer to the center in the width direction of the lens array than a light emitter array that emits light of high color. And the above and Similarly, it is possible to obtain the effect of suppressing the power supply voltage while enabling the respective light emitters to be driven so that the amount of light that causes the color paper 1 to develop color at the maximum density can be obtained. In the above-described embodiment, an example of an exposure apparatus using three light emitter arrays that emit red light, green light, and blue light has been described. , An exposure apparatus having a light emitting head that emits light other than red light, green light, and blue light, and a plurality of light emitter arrays that emit light of two different colors, respectively. It is also possible to apply to an exposure apparatus equipped with a light emitting head having a light emitting head, and an exposure apparatus equipped with a light emitting head having a plurality of light emitter rows each emitting light of four or more different colors. It is.

Next, the case where the color balance is taken into consideration so that the exposure energy (exposure light amount) for developing each color with the same density on the photosensitive material is the same for each color will be described. Fig. 9A is a diagram showing the spectral sensitivity of photosensitive material on the coordinate with wavelength on the horizontal axis and sensitivity on the vertical axis, and Fig. 9B is normalized for each color on the coordinate with wavelength on the horizontal axis and power on the vertical axis Fig. 9C is a diagram showing the power spectrum, Fig. 9C is a diagram showing the relative visibility on the coordinate with the wavelength on the horizontal axis and the sensitivity on the vertical axis, and Fig. 10 is the driving voltage of the light emitter and the light emitted from this light emitter. It is a figure which shows the relationship with the brightness | luminance of light.

The colors of the three light-emitting elements are red, green, and blue, and the power spectrum of each color is denoted as _{κ κ} (λ), P _c (e), and Ρ _Β (λ). In addition, when the spectral sensitivity characteristics of the photosensitive material (hereinafter also referred to as photosensitive material) to be exposed are set to F _R (λ), F _G (X), and F _B (i), the following There is a relationship. Fig. 9A shows the spectral sensitivity F (E) of the photosensitive material.

E _R = ί F _R (E) · P _R ) d λ (1)

E _G = JF _G (λ) P _G (X) d λ (2)

E _B = i F _B (X)-P _B (X) d (3)

Here, E _R , E _G , and E _B represent exposure energy contributing to exposure in each color. The power spectrum shows the actual energy, but the spectrum measurement generally only looks at the distribution, and the absolute value is often omitted. Therefore, P When the normalized power spectrum with a peak value of 1 is P (λ), the following relationship is shown. Figure 9 (b) shows the standardized spectrum of ρ (e).

Ρ _κ (λ) = a _R · p _R (X) (4)

P _G (1) = a _G _pG (X) (5)

Ρ _Β (λ) = a _B 'PB (^) (6)

Therefore, equations (1) to (3) are as follows.

_{_{E R = a RJF R (λ}} ) · p R (X) d λ (7)

E _G = a G j F _G (A)-p _G (A) dl (8)

E _B = a B ί F _B (λ) pB (λ) d λ (9)

When considering the color balance of exposure prints, the exposure energy must match for each color.

E _R = E _G = Ε _Β (10)

These conditions need to be met. From equations (7) to (9) and (10),

R: _Q a B

= 1 / JF _R () · p _R () d λ: 1 / JF _G (λ) · p G (λ) d λ

: 1 / ί F _B (λ) · p B (λ) d λ (11)

The relationship is guided.

In general, light emitting elements such as organic EL measure the luminance by measuring the luminance, but the luminance has the following relationship as a value obtained by multiplying the power spectrum and the relative visibility. Fig. 9C shows the relative visibility V (E).

L _G ∞ a _G JV ()-p _G (X) dl (13)

L _B ∞ _{a B} JV (l)-p _B (X) d Z (14)

L represents luminance, and V (λ) represents specific luminous efficiency characteristics. (12) to (14)

L R G

= a _R ί V (λ)-ρ _R (λ) d λ: a _G ί V (λ) · p _G (λ) d λ

: A BIV (λ) · p B (λ) d λ (15) When the relationship of (11) is combined,

L _R. L _G. L _B

= ί V (λ) p _R (X) d X / i F _R (l)-ρ R (λ) d λ

: Ί V (λ)-p _e (; t) d A / j F; L) 'ρ _G (X) d λ

: Ί ν (λ)-p _B (X) d X / j F _B ()-ρ _Β (λ) ά λ (1 6) This shows the relationship between the brightness of each color giving the same exposure energy for each color.

Here, a method for determining the arrangement when the voltage-luminance characteristics of the respective light emitting elements are as shown in FIG. 10 will be described. The result of calculating L _R : L _G : L _B by putting ρ (λ) and F (λ) of each color of the system that actually performs exposure printing in Eq. (16) into Eq. (16) is shown in the figure. Assume that the ratio is shown on the vertical axis of 10. The voltage values (V _R , V _G , V _B ) corresponding to the luminance of each color are determined from the voltage-luminance characteristics in Fig. 10. [(16) is the relative ratio of luminance, and the absolute value cannot be obtained. It is desirable to obtain the voltage value from the absolute value of the brightness, based on the brightness that matches the exposure conditions when actually printing. ] If this result is V _B > V _R > V _G as shown in Fig. 10, the blue element with the highest voltage is placed in the center of the secondary running direction, and the green element with the lowest voltage is It is arranged at the peripheral part in the sub-scanning direction of the central part. As shown in FIG. 1 0, V _R and V _B are relatively value is close, when there is a tendency that apart relative to VG, across the center of the lens array portion as the arrangement shown in FIG. 8 It is desirable to arrange red and blue and green farthest from the lens center. Further, since the voltage of the blue element is slightly higher than that of the red element, it is desirable to arrange the blue element closer to the center of the lens array portion than the red dye. In this way, the color luminance ratio is calculated from the power spectrum of each color and the sensitive material spectral sensitivity in the actual exposure printing system, and the voltage of each color is calculated from the voltage-luminance characteristics of each color element. You can ask for the placement.

Up to now, the explanation has been made with the element that emits light independently for each color, but it can also be applied to the case where a filter that transmits only light of each RGB color is placed in front of the light emitting element that emits white light. . When F (λ) is the spectral transmittance of each color filter and Ρ _Μ (λ) is the power spectrum of each light source, the power spectrum of each color is P _R U) = F _R U) · _Μ (λ) (1 7)

P _G (1) = F _G () · Ρ _Μ (λ) (1 8)

P _B (= F _B U) · _Μ λ (λ) (1 9)

It becomes. If each power spectrum in the above equation is normalized and the normalized power spectrum is obtained, the luminance ratio can be obtained from equation (16). The brightness in this case is not the brightness of the light source itself, but the transmission brightness when a filter is attached to a monochromatic light source.

Claims

Billed

1. There are a plurality of light emitter rows in which a large number of light emitters emitting the same color of light are arranged in a row, and each light emitter row emits light of a different color. ,

An exposure apparatus comprising: a lens array unit composed of a plurality of lenses arranged in one direction, which images each light emitted from the light emitter on a photosensitive material,

The light emitting head emits light having a color development efficiency lower than that of the light emitter array that emits light having a high color development efficiency when the photosensitive material is exposed to color. An exposure apparatus characterized in that the light emitter array that emits light is positioned closer to the center in the width direction of the lens array section.

2. The exposure apparatus according to claim 1, wherein the different colors are red, green, and blue.

3. The exposure apparatus according to claim 1, wherein each lens constituting the lens array unit is a gradient index lens.

4. The exposure apparatus according to claim 1 or 2, wherein the lens array section is a microlens array.

5. The exposure apparatus according to any one of claims 1 to 4, wherein the light emitter is composed of an organic EL element, an inorganic EL element, or an LED element.