JP2001350207A - Exposure device, photographic processing device and exposure method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a sufficient gradation change in exposure images by using a D/A converter (for example, 8 bits) of a commercially marketed product level. SOLUTION: The exposure device is provided with a separation section 41 for separating the image data of N bits (for example, 12 bits) to upper A bits (for example, 4 bits) and lower B bits (for example, 8 bits). The device is provided with digital-to analog converters 29R1 and 29R2 for converting the image data of the upper a bits and the lower B bits respectively to analog data. The device is provided with AOM 12R1 and 12R2 in correspondence to the respective digital-to analog converters 29R1 and 29R2, and is provided with an attenuator 44 to attenuate the laser beam modulated by the AOM 12R1 in such a manner that its light quantity attains, for example, 2B/2N. The laser beam modulated by the AOM 12R1 and the laser beam attenuated by the attenuator 44 are synthesized, by which the light quantity corresponding to the image data of the original N bits may be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure apparatus and a photographic processing apparatus which form an image on a photographic paper by exposing a photographic paper as a photosensitive material using a laser beam modulated based on digital image data. And a D / A converter (D / A converter) for D / A converting the digital image data.
), A photographic processing apparatus, and an exposure method.

[0002]

2. Description of the Related Art Conventionally, analog exposure and digital exposure have been known as exposure systems for printing photographs. The analog exposure is a method of irradiating a photographic film on which an original image is recorded with light, and irradiating the photographic paper with light transmitted through the photographic film, so that the original image is printed on the photographic paper. On the other hand, digital exposure means that monochromatic light of red, green, and blue is applied to each pixel based on image data obtained by reading an image on a photographic film by a scanner or image data obtained by photographing with a digital camera. In this method, an image corresponding to the image data is printed on the printing paper by irradiating the printing paper on the printing paper.

[0003] Digital exposure is further roughly classified into surface exposure and scanning exposure. Surface exposure is a method in which a two-dimensional image is displayed on the entire surface of a light modulation element (for example, an LCD (Liquid Crystal Display)), and the displayed image is directly printed on photographic paper. On the other hand, the scanning exposure is a method of printing a two-dimensional image on a printing paper by irradiating light from a light source in the main scanning direction of the printing paper while conveying the printing paper in the sub-scanning direction.

Here, various types of exposure apparatuses for performing scanning exposure have been proposed. For example, those using laser light sources corresponding to red (R), green (G), and blue (B) as the light source are described. There is. In this type of exposure apparatus, for example, digital image data of 8 bits (0 (black) to 255 (white)) is converted into analog data by a D / A converter.
Laser light of each color is modulated based on the analog data. The modulation of the laser light is performed by the AOM corresponding to each color.
(Acousto-Optic Modulator). Then, the laser light modulated by each AOM is deflected in the main scanning direction by a deflector such as a polygon mirror, and is irradiated onto photographic paper via an optical system such as an fθ lens. At this time, the photographic paper is simultaneously conveyed in the sub-scanning direction, so that a two-dimensional color image is finally printed on the photographic paper.

[0005]

By the way, for example, an electrostatic latent image corresponding to image data is formed on a photosensitive drum,
In a copier which develops the toner image using toner and transfers the toner image to a recording medium (for example, paper), the density of the obtained image is proportional to the amount of toner adhered.
(Y), M (magenta), and C (cyan), a full-color image can be sufficiently obtained by using 8-bit image data for each color.

However, in the field of photographic processing, photographic paper having a color developing characteristic as shown in FIG. 7 is used as a medium for forming an image. Therefore, to express full color on the photographic paper, 8-bit image data is used. Is not enough. That is, the relationship between the image data corresponding to each pixel and the color density of the photographic paper is non-linear.
At around 55, the change in the color density with respect to the change in the image data is gradual, so if the image was printed on photographic paper using the image data of 256 gradations as it was, a low density portion of the image (around image data 0) ) And a density change (gradation change) in a high density portion (around the image data 255) cannot be expressed well.

Therefore, as a method of solving such inconvenience, for example, an LUT (look-up table) for converting 8-bit input image data into 12-bit image data such that the density is proportional to the image data is obtained. Provided,
A configuration in which 12-bit image data is supplied to a D / A converter is conceivable. The D / A converter is provided in a stage preceding the AOM driver for driving the AOM, and generates an analog value necessary for driving the AOM driver from digital image data.

[0008] However, the D /
Most A-converters are 8-bit compatible, and 12-bit compatible D / A converters are several tens of times more expensive than 8-bit compatible D / A converters. This is because the use of a high-resolution D / A converter such as a 12-bit converter is limited to special industrial equipment. In addition, since the conversion by the D / A converter takes more time as the number of bits increases, in view of such a conversion speed, the 12-bit compatible D / A converter converts one dot on the photographic paper to 50 to 70 dots.
This is unsuitable for the above exposure apparatus that forms at a scanning speed of ns.

That is, a high-speed, high-resolution and inexpensive D /
At present, there is almost no A converter at a commercial product level. Therefore, in the above exposure apparatus, there is a problem that it is not possible to obtain an image rich in gradation expression by increasing the number of bits of input image data.

A method of converting 8-bit image data into 8-bit data so that the relationship between the input image data and the color density becomes linear is conceivable. However, in this method, only discrete values can be obtained. This is not desirable because the number of gradations that can be expressed is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a sufficient gradation in an exposed image even when a commercially available D / A converter (for example, 8 bits) is used. An object of the present invention is to provide an exposure apparatus, a photographic processing apparatus, and an exposure method that can make a change.

[0012]

According to a first aspect of the present invention, there is provided an exposure apparatus wherein, when N is a positive integer of 2 or more, N-bit image data is converted into a plurality of bits. A data separating means for separating the data into groups, a plurality of converting means for converting the image data of each bit group into analog data, and a plurality of converting means for converting the image data of each bit group into analog data; Modulating a light beam based on data, comprising a plurality of modulating means for supplying the modulated light beam to a photosensitive material, and a light beam supplying means for supplying a light beam to each of the modulating means. I have.

According to the above configuration, N bits (for example, 1 bit)
The (2 bits) image data is separated into a plurality of bit groups (for example, upper 4 bits and lower 8 bits, or 3 or more bit groups) by a data separating unit. The image data of each bit group is converted into analog data by a corresponding conversion unit. Then, the light beam supplied to each modulating means is modulated based on the analog data corresponding to the modulating means, and supplied to the photosensitive material.

As described above, since the original N bits are divided into a plurality of bit groups and the light beams are separately modulated by the modulation means corresponding to each bit group, each conversion means corresponding to each modulation means is provided. , Which correspond to a smaller number of bits than the original N bits. For example, since there are many 4-bit or 8-bit conversion means at the level of a commercially available product, high-speed conversion is possible because the number of bits is smaller than that of the original N-bit conversion means, and the cost is low. It is.

Therefore, the gradation expression based on the original N-bit image data can be realized on the photosensitive material using the high-speed and low-cost conversion means of a commercial product without using the original N-bit conversion means. It is possible to do.

Further, in the above configuration, since the light beam is modulated by each modulation means, the light amount of the light beam supplied by the light beam supply means may always be kept constant. This makes it possible to configure the light beam supply means with a light amount that cannot be adjusted at high speed in accordance with, for example, image data (for example, one including a solid-state laser). The degree of freedom in configuration can be increased.

According to a second aspect of the present invention, there is provided an exposure apparatus according to the first aspect, wherein the light beam supply means comprises: a light source for emitting a light beam; And a spectroscopic means for supplying the light to each modulating means.

According to the above arrangement, since the light beam emitted from the light source is split by the spectroscopic means and supplied to each modulation means, a single light source can be used as the light source. This makes it possible to configure the light source portion at a lower cost, for example, as compared with a configuration in which a plurality of light sources are provided corresponding to each modulation unit. This effect becomes greater as the light source is formed of an expensive device such as a solid-state laser.

According to a third aspect of the present invention, there is provided an exposure apparatus, wherein A and B are positive integers in the configuration of the second aspect.
Bit image data is separated into upper A-bit image data and lower B-bit image data.
The light quantity ratio between the light beam obtained through the first modulating means as the modulating means corresponding to the bit and the light beam obtained through the second modulating means as the modulating means corresponding to the lower B bits is equal to the original light amount. Attenuation for attenuating the light beam incident on the second modulating means or the light beam emitted from the second modulating means so that the ratio corresponding to the image corresponding to the N-bit image data can be reproduced on the photosensitive material. It is characterized by further comprising means.

According to the above arrangement, the N-bit image data is separated into upper A-bit image data and lower B-bit image data by the data separating means. The upper A-bit image data and the lower B-bit image data are converted into analog data by the corresponding conversion means. The light beam supplied to the first modulating means corresponding to the upper A bits is modulated by the first modulating means based on the analog data corresponding to the upper A bits, while the second light beam corresponding to the lower B bits is modulated. The light beam supplied to the modulator is modulated by the second modulator based on analog data corresponding to the lower B bits.

Here, the light beam incident on the second modulating means or the light beam emitted from the second modulating means is attenuated by the attenuating means. At this time, the light beam includes a light beam obtained through the first modulation unit (hereinafter, referred to as a first light beam) and a light beam obtained through the second modulation unit (hereinafter, a second light beam). ) Is attenuated so that an image corresponding to the original N-bit image data can be reproduced on the photosensitive material.

If it is assumed that the light is separated by the above-mentioned spectral means so that the light amounts become equal, the light amount ratio may be, for example, 2 ^N : 2 ^B. Here, when the optical attenuation of the light beam other than the attenuating means in the optical path is not taken into account, the attenuating means sets the light beam incident on the second modulating means or the light beam emitted from the second modulating means to have a light quantity of less. if it brought into attenuated so that 2 ^B / 2 ^N, it is possible to obtain the light amount ratio. On the other hand, when the optical attenuation of the light beam is taken into account, the attenuating means converts the light beam incident on the second modulating means or the light beam emitted from the second modulating means into a light amount, for example, in anticipation of the optical attenuation. There by attenuating so that approximately 2 ^B / 2 ^N, the rear optical attenuation in the final light amount ratio 2 ^N: it is possible to obtain a 2 ^B.

The attenuating means attenuates the light beam incident on the second modulating means or the light beam emitted from the second modulating means so as to obtain a predetermined light quantity ratio, thereby converting the N-bit image data into the upper A bits. Even if the light beams are separately modulated by dividing the light beams into lower-order B bits, a light beam having an amount of light corresponding to the original N-bit image data can be reliably obtained. As a result, by supplying each light beam modulated based on the image data of each bit group to the photosensitive material,
An image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material.

According to a fourth aspect of the present invention, there is provided an exposure apparatus according to the third aspect, wherein the light quantity ratio is determined in an optical path from the light beam supply means to the photosensitive material. The ratio is such that an image corresponding to the original N-bit image data can be reproduced on the photosensitive material by taking into account the optical attenuation of the light beam by means other than the attenuating means.

For example, if the light amount ratio is 2^N: 2^BWhen
The image corresponding to the original N-bit image data is
It can be reproduced on the material. In this case, the light beam
Optical attenuation of light beam in roads other than attenuation means
If not, the attenuation means may be a second modulation means.
The light beam incident on
The light beam to be emitted is, for example, 2^B/ 2^NSo that
If it is attenuated, the light intensity ratio will be 2 ^N: 2^BCan be obtained.

However, the light beam emitted from the light source is
For example, if there is a slight
In such a case, the attenuating means converts the light beam to a light amount of 2^B
/ 2 ^NIf you attenuate so that
Light intensity ratio is 2^N: 2^BWill be slightly different.

Therefore, in the above configuration, the optical path of the light beam
In consideration of the optical attenuation at
Images corresponding to different image data can be reproduced on photosensitive materials
Optical ratio in the optical path of the light beam
Even if attenuation occurs, the original N-bit image data
The corresponding image can be reliably reproduced on the photosensitive material.
Become. In this case, the optical attenuation is reduced in anticipation of the optical attenuation.
Decay means light beam roughly 2^B/ 2^NWill be
By attenuating the light intensity in the final ^N: 2^B
Can be obtained.

According to a fifth aspect of the present invention, there is provided an exposure apparatus, wherein A and B are positive integers in the configuration of the second aspect.
Bit image data is separated into upper A-bit image data and lower B-bit image data, and the spectroscopic unit includes a light beam directed to a first modulation unit as a modulation unit corresponding to the upper A bits. light amount ratio is 2 ^N of the light beam toward the second modulation means as a modulation means corresponding to the lower B bits: so that 2 ^B, is characterized by that splits the light beam from the light source.

According to the above arrangement, the N-bit image data is separated into upper A-bit image data and lower B-bit image data by the data separating means. The upper A-bit image data and the lower B-bit image data are converted into analog data by the corresponding conversion means. The light beam supplied to the first modulating means corresponding to the upper A bits is modulated by the first modulating means based on the analog data corresponding to the upper A bits, while the second light beam corresponding to the lower B bits is modulated. The light beam supplied to the modulator is modulated by the second modulator based on analog data corresponding to the lower B bits.

Here, since the light splitting means splits the light beam from the light source so that the light quantity ratio of the light going to the first modulation means and the light going to the second modulation means becomes 2 ^N : 2 ^B ,
Even if the light beam is separately modulated by dividing the bit image data into upper A bits and lower B bits, a light beam having an amount of light corresponding to the original N bits of image data can be reliably obtained. As a result, by supplying each light beam modulated based on the image data of each bit group to the photosensitive material, an image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material. Becomes

In the above arrangement, the original N-bit image can be reproduced on the photosensitive material by dispersing the light beam at the above-mentioned spectral ratio and performing light modulation. Unlike the configuration, there is no need to provide an attenuation unit for adjusting the light amount. Thereby, the configuration of the device can be simplified.

According to a sixth aspect of the present invention, there is provided an exposure apparatus, wherein a and b are positive integers in the configuration of the third aspect.
Light amount ratio is 2 ^a of the light beam toward the optical beam and the second modulating means toward the modulating means: as a 2 ^b, are those that splits light beam from said light source, said attenuating means, the The light beam incident on the second modulating means or the light beam emitted from the second modulating means is converted into a light quantity of 2 ^B / 2.
It is characterized by being attenuated to become ^{N- (ab)} .

According to the above configuration, by setting the spectral ratio of the spectroscopic means as described above and the attenuation ratio of the attenuating means as described above, the first light beam and the second light beam are separated. The final light amount ratio is a ratio at which the original N-bit image can be reproduced on the photosensitive material. as a result,
By supplying the first light beam and the second light beam to the photosensitive material, an image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material.

According to a seventh aspect of the present invention, in the exposure apparatus according to the third aspect of the present invention, the dispersing means disperses the light beam from the light source so that the light amount is uniform. Wherein the attenuating means attenuates the light beam incident on the second modulating means or the light beam emitted from the second modulating means so that the light quantity becomes 2 ^B / ^2N. I have.

According to the above arrangement, when the light splitting means equally splits the light beam from the light source and supplies it to each modulation means, the light quantity ratio between the first light beam and the second light beam is 2 ^N : 2
Since the ^B, if not consider optical attenuation in the optical path of the light beam, it is modulated separately light beams divided image data of N bits into upper A bits and lower B bits,
A light beam having an amount of light corresponding to the original N-bit image data can be reliably obtained. As a result, by supplying each light beam modulated based on the image data of each bit group to the photosensitive material, an image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material. Becomes

According to an eighth aspect of the present invention, in the exposure apparatus according to the first aspect of the present invention, the light beam supply means includes a light source for emitting a light beam provided to each modulation means. It is characterized by being provided correspondingly.

According to the above configuration, since the light source for emitting the light beam is provided corresponding to each of the modulating means,
The light amount of the light beam supplied to each modulation means can be adjusted for each light source. Thereby, in order to obtain the light amount corresponding to the original N-bit image data, a member for adjusting the light amount ratio of the light beam obtained through each modulation unit (for example, the light obtained through a predetermined modulation unit) Means for attenuating the beam).

According to a ninth aspect of the present invention, in order to solve the above-mentioned problems, in the configuration of the eighth aspect, when A and B are positive integers, the data separating means includes N
Bit image data is separated into upper A-bit image data and lower B-bit image data.
The ratio of the amount of emitted light between the first light source as a light source that supplies a light beam to the modulation unit corresponding to the bit and the second light source as a light source that supplies a light beam to the modulation unit corresponding to the lower B bits is: The ratio is set so that an image corresponding to the original N-bit image data can be reproduced on a photosensitive material.

According to the above arrangement, the N-bit image data is separated into upper A-bit image data and lower B-bit image data by the data separating means. The upper A-bit image data and the lower B-bit image data are converted into analog data by the corresponding conversion means. The light beam supplied to the modulating means corresponding to the upper A bits is modulated based on the analog data corresponding to the upper A bits, while the light beam supplied to the modulating means corresponding to the lower B bits is modulated by the lower B bit. The modulation is performed based on the analog data corresponding to the bit.

Here, a first light source as a light source for supplying a light beam to the modulation means corresponding to the upper A bits, and a second light source as a light source for supplying a light beam to the modulation means corresponding to the lower B bits Is equal to the original N
The ratio is set so that an image corresponding to the bit image data can be reproduced on the photosensitive material. The above-mentioned emission light amount ratio is, for example, 2 ^N when the optical attenuation of the light beam in the optical path from the light source to the photosensitive material is not taken into account.
2 ^B can be considered. On the other hand, when the optical attenuation is taken into consideration, for example, approximately 2 ^N : 2 ^B can be considered.

Since the output light amount ratio is set as described above, even if the N-bit image data is divided into upper A bits and lower B bits and the light beam is modulated separately,
A light beam having an amount of light corresponding to the original N-bit image data can be reliably obtained. As a result, by supplying each light beam modulated based on the image data of each bit group to the photosensitive material, an image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material. Becomes

According to a tenth aspect of the present invention, in the exposure apparatus according to the ninth aspect, the ratio of the amount of the emitted light is determined in an optical path from the light beam supply means to the photosensitive material. The ratio is set so that an image corresponding to the original N-bit image data can be reproduced on the photosensitive material in consideration of the optical attenuation of the light beam.

Assuming that the optical beam does not attenuate optically in the optical path, by setting the output light amount ratio to 2 ^N : 2 ^B , the light obtained through the modulating means corresponding to the upper A bits can be obtained. An image corresponding to the original N-bit image data can be reproduced on the photosensitive material by the beam and the light beam obtained through the modulating means corresponding to the lower B bits.

However, when optical attenuation of the light beam occurs in the optical path, the output light amount ratio is set to 2 ^N : 2.
Even if it is set to ^B , a light beam with a light amount corresponding to the original N-bit image data cannot be obtained due to a decrease in the light beam amount due to optical attenuation. As a result, an image corresponding to the original N-bit image data cannot be reproduced on the photosensitive material.

In view of the above, in the above-described configuration, taking into account the optical attenuation of the light beam in the optical path, the ratio of the emitted light amount can be reproduced on the photosensitive material (for example, a ratio capable of reproducing an image corresponding to the original N-bit image data). With approximately 2 ^N : 2 ^B ), an image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material even if optical attenuation occurs in the optical path of the light beam. It becomes possible.

According to an eleventh aspect of the present invention, in order to solve the above-mentioned problem, in the configuration of the ninth aspect, the ratio of the amount of emitted light is set to 2 ^N : 2 ^B. And

According to the above configuration, since the ratio of the amount of emitted light is set to 2 ^N : 2 ^B , if optical attenuation of the light beam in the optical path is not considered, N-bit image data is used. Is divided into upper A bits and lower B bits, and the light beams are modulated separately, a light beam having a light amount corresponding to the original N-bit image data can be reliably obtained. As a result, by supplying each light beam modulated based on the image data of each bit group to the photosensitive material, an image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material. Becomes

According to a twelfth aspect of the present invention, in order to solve the above-mentioned problems, the exposure apparatus according to any one of the first to eleventh aspects condenses a light beam obtained through each modulating means. It is characterized by further comprising a light condensing means for supplying the photosensitive material.

According to the above arrangement, the light beam obtained through each modulating means is condensed by the condensing means,
It is possible to collectively irradiate the same pixel of the photosensitive material with the light beam obtained through each modulation means at the same timing. As a result, even if a plurality of modulating means are used, the original N
Exposure similar to the case of performing exposure based on bit image data can be realized.

A photographic processing apparatus according to a thirteenth aspect of the present invention
In order to solve the above problems, the exposure apparatus according to any one of claims 1 to 12, and a developing unit that develops an image formed on a photosensitive material by the exposure apparatus is provided. I have.

According to the exposure apparatus of any one of claims 1 to 12, expensive N bits (for example, 12 bits)
An image corresponding to the original N-bit image data can be printed on the photosensitive material without using a corresponding conversion unit. Therefore, by realizing the photographic processing apparatus at low cost with such an exposure apparatus and a developing unit, it is possible to provide a photograph rich in gradation expression to a customer at low cost.

According to a fourteenth aspect of the present invention, in order to solve the above problem, when N is a positive integer, N
Separating the bit image data into a plurality of bit groups, converting the image data of each bit group into analog data by individual conversion means, and converting the light supplied from the light beam supply means to the individual modulation means. Modulating the beam based on individual analog data and supplying the modulated light to a photosensitive material.

According to the above configuration, N bits (for example, 1 bit)
(2 bits) image data is separated into a plurality of bit groups (for example, upper 4 bits and lower 8 bits, or 3 or more bit groups). The image data of each bit group is converted into analog data by a corresponding conversion unit. And
Light beams supplied from the light beam supply means to the respective modulation means are respectively modulated based on analog data corresponding to the modulation means and supplied to the photosensitive material.

As described above, since the original N bits are divided into a plurality of bit groups, and the light beams are separately modulated by the modulation means corresponding to each bit group, each conversion means corresponding to each modulation means is used. , Which correspond to a smaller number of bits than the original N bits. For example, since there are many 4-bit or 8-bit conversion means at the level of a commercially available product, high-speed conversion is possible because the number of bits is smaller than that of the original N-bit conversion means, and the cost is low. It is.

Therefore, the gradation expression based on the original N-bit image data can be realized on the photosensitive material using the high-speed and inexpensive commercial-level conversion means without using the original N-bit conversion means. It is possible to do.

Further, in the above configuration, since the light beam is modulated by each of the modulation means, the light quantity of the light beam supplied to each of the modulation means may always be constant. This makes it possible to configure the light beam supply unit with a light amount that cannot be adjusted at high speed in accordance with, for example, image data (for example, a light beam including a solid-state laser). The degree of freedom in configuration can be increased.

[0057]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [Embodiment 1] An embodiment of the present invention will be described below with reference to the drawings.

The photographic processing apparatus according to this embodiment prints on a photosensitive material based on image data of an original image,
This is a digital photographic printer that prints an original image on a photosensitive material by performing development and drying processes.

FIG. 2 is a perspective view showing the structure of the photographic processing apparatus. As shown in FIG. 2, the photographic processing apparatus includes a printing unit 1, a photographic paper storage unit 2, a developing unit 3, a drying unit 4,
C (Personal Computer) 5 is provided.

The photographic paper storage unit 2 stores photographic paper P (see FIG. 3) as a photosensitive material to be supplied to the printing unit 1. For example, two papers for storing roll-shaped photographic paper P are provided. The magazines 2 a and 2 b are provided above the printing unit 1. The paper magazines 2a and 2b store photographic papers P of different sizes (widths).
The printing paper P corresponding to the size of the output image is supplied to the printing unit 1 from the paper magazine 2a (or 2b). It is also possible to provide a cutter in the middle of the transport path of the printing paper P to the printing unit 1 and supply the printing paper P in sheet form to the printing unit 1.

As shown in FIG. 3, the printing section 1 has an exposure section 6
(Exposure device) and transport rollers R1 to R5. The exposure unit 6 modulates the laser light based on the image data, and applies the photographic paper P in a direction (hereinafter, a sub-scanning direction) substantially perpendicular to a scanning direction of the laser light (hereinafter, referred to as a main scanning direction). The photographic paper P is exposed while being conveyed, and is the most characteristic part of the present invention. The image data for modulating the laser light is obtained by, for example, a scanner or a digital camera that reads a photographic film. The details of the exposure unit 6 will be described later.

The transport rollers R1 to R5 are provided in the photographic paper storage unit 2.
The photographic paper P supplied from the printer is sent to the developing unit 3 via the exposure unit 6. For example, the photographic paper P stored in the paper magazine 2a is transported by rollers R1.
The printing paper P transported in order by R2, R3, and R4 and stored in the paper magazine 2b is transported by a transport roller R5.
-It is transported in order by R2, R3, and R4.

The developing section 3 develops the image printed on the photographic paper P by transporting the photographic paper P subjected to the printing processing in the printing section 1 while immersing it in various developing solutions. . The drying unit 4 is for drying the photographic paper P developed by the developing unit 3 by, for example, blowing hot air.

The PC 5 has a function of storing image data of the original image, a function of performing data processing on the image data, and the like. The PC 5 manages a man-machine interface of the entire photo processing apparatus, and can input, for example, actual print conditions and input / confirm settings of the photo processing apparatus via the PC 5. It is possible.

In addition to the above, the present photographic processing apparatus
A plurality of control CPUs (not shown) for controlling the operation of the entire photographic processing apparatus are provided.

The photographic processing apparatus according to the present embodiment uses the C
Under the control of the PU, the exposure, the development processing, and the drying processing of the photographic paper P are continuously performed under unitary management.
Therefore, it is possible to print a large number of photographs continuously without putting a burden on the user in operation.

Next, in the above-described exposure unit 6, first, a basic configuration which is a premise of the present invention will be described. FIG.
FIG. 3 is an explanatory diagram illustrating a schematic configuration of an exposure unit. The exposure unit 6
Light source unit 7, scanning unit 8, transport unit 9, and data supply unit 26
(See FIG. 5), and the overall operation of the exposure unit 6 is controlled by an overall control unit 51 (see FIG. 5). Hereinafter, each configuration will be described.

(Structure of Light Source Unit) The light source unit 7 has a red color.
It comprises light source units 7R, 7G, and 7B for supplying laser beams of respective colors of green (Green) and blue (Blue) to the scanning unit 8.

The light source section 7R includes a red LD (Laser Diode) 1
0R, lens group 11R, AOM (Acousto-Optic Modula)
tor: acousto-optic modulator) 12R, dimmer 13R, mirror 14R and AOM driver 15R. The lens group 11R, the AOM 12R, and the dimmer 13R are arranged in this order on the optical axis from the red LD 10R to the mirror 14R.

The red LD 10R is a semiconductor laser that emits laser light having a wavelength of a red component. The lens group 11
R is a lens group for shaping the red laser light emitted from the red LD 10 and guiding the red laser light to the light entrance of the next AOM 12R.

The AOM 12R is an optical modulator using a so-called acousto-optic diffraction, which is a diffraction phenomenon in which a refractive index distribution created in a transparent medium by a sound wave acts as a phase diffraction grating, and changes the intensity of an applied ultrasonic wave. This modulates the intensity of the diffracted light.

The AOM 12R has an AOM driver 1
5R is connected. The AOM driver 15R outputs a high-frequency signal to the AOM1 in synchronization with a pixel clock described later.
2R. The above high-frequency signal is a signal whose amplitude is modulated in accordance with image data corresponding to each dot in the main scanning direction of the photographic paper P.

Therefore, AOM12R is
When a high-frequency signal is input from the M driver 15R, an ultrasonic wave according to the high-frequency signal propagates in the acousto-optic medium. When laser light passes through such an acousto-optic medium, diffraction occurs due to the effect of the acousto-optic effect,
AOM12 is a laser beam having an intensity corresponding to the amplitude of the high-frequency signal.
It is emitted from R as diffracted light. As a result, AOM12
From R, a laser beam of an amount corresponding to the image data is emitted for each pixel of the photographic paper P.

The dimming unit 13R diminishes (fine-adjusts the amount of light) the laser light emitted from the AOM 12R and modulated in accordance with image data, and includes, for example, an ND filter or a plurality of light-emitting devices having different sizes. And the like. Light emitting elements such as semiconductor lasers and solid-state lasers have a fixed light amount range in which light can be emitted in a stable state. Therefore, light control by the light control section 13R allows a wide dynamic range according to the color development characteristics of photographic paper. Exposure can be performed in a light amount range that is a range.

The mirror 14R reflects the laser light emitted from the light control section 13R in the direction in which the scanning section 8 is arranged. This mirror 14R outputs
Any mirror that reflects the red component light may be used. In the present embodiment, since a red laser beam having only the wavelength of the red component is incident on the mirror 14R, a mirror that totally reflects the incident light is used as the mirror 14R.

On the other hand, the light source section 7G has a green SHG (Second
Harmonic Generation) Laser unit 10G, AOM1
2G, a dimming unit 13G, a dichroic mirror 14G, and an AOM driver 15G. The AOM 12G and the dimmer 13G are provided with a green SHG laser unit 10G.
Are arranged in this order on the optical axis extending from the light source to the dichroic mirror 14G.

The green SHG laser unit 10G functions as a light source that emits laser light having a wavelength of a green component. Inside the green SHG laser unit 10G, although not shown, a solid-state laser such as a YAG laser and a second-harmonic generation unit for extracting a second harmonic from laser light emitted from the solid-state laser are provided. A variable wavelength unit and the like are provided. For example, YA
When a laser beam having a wavelength of 1064 nm is emitted from the G laser, a laser beam having a wavelength of 532 nm (green component) is generated in the second harmonic generation unit, and the laser beam having the second harmonic component is emitted. Will be. In the configuration of the present embodiment, a solid-state laser is used as a unit that emits a basic laser beam. However, the present invention is not limited to this. For example, an LD may be used. Further, inside the green SHG laser unit 10G, a light source unit 7R is provided.
A lens having a function equivalent to that of the lens group 11R provided in is provided.

The AOM 12G and the dimming unit 13G are the same as the AOM 12R and the dimming unit 13 described in the light source unit 7R.
It has the same configuration as R. That is, AOM12G
AOM converts a high-frequency signal whose amplitude is modulated in accordance with image data input in synchronization with a pixel clock described later into an AOM.
It is connected to the AOM driver 15G that supplies 12G. The AOM 12G outputs the laser light emitted from the green SHG laser unit 10G to the AOM driver 1
Modulation is performed in accordance with the high-frequency signal supplied from 5G, and light is emitted for each pixel of the photographic paper P with a light amount corresponding to image data. The dimmer 13G performs fine adjustment of the light amount of the laser light emitted from the AOM 12G.

The dichroic mirror 14G is connected to the dimming unit 1
The laser light of the green component emitted from 3G is reflected in the direction in which the scanning unit 8 is arranged. The dichroic mirror 14G has a property of reflecting only light of a wavelength of a green component and transmitting light of other wavelengths. The dichroic mirror 14G is disposed on an optical path from the mirror 14R of the light source unit 7R to the scanning unit 8, and the red laser light reflected by the mirror 14R passes through the dichroic mirror 14G and is transmitted to the scanning unit 8. Will arrive. That is, the light traveling from the dichroic mirror 14G toward the scanning unit 8 is composed of a red component laser beam and a green component laser beam modulated according to image data.

The light source unit 7B has substantially the same configuration as the light source unit 7G, and the blue SHG laser unit 10
B, AOM 12B, dimming unit 13B, dichroic mirror 14B, and AOM driver 15B. A
The OM 12B and the dimmer 13B are arranged in this order on the optical axis from the blue SHG laser unit 10B to the dichroic mirror 14B.

The blue SHG laser unit 10B functions as a light source that emits laser light having a wavelength of a blue component, and has substantially the same configuration as the green SHG laser unit 10G. The AOM 12B and the dimming unit 13B are the same as the AOM 1 described in the light source units 7R and 7G.
It has the same configuration as the 2R · 12G and the dimmers 13R / 13G. That is, the AOM 12B is connected to the AOM driver 15B that supplies the AOM 12B with a high-frequency signal whose amplitude is modulated according to image data input in synchronization with a pixel clock described later. And A
The OM 12B modulates the laser light emitted from the blue SHG laser unit 10B according to the high-frequency signal supplied from the AOM driver 15B, and emits the light with a light amount corresponding to the image data for each pixel of the printing paper P. Light control unit 1
3B performs fine adjustment of the light amount of the laser light emitted from the AOM 12B.

The dichroic mirror 14 B
The laser beam of the blue component emitted from 3B is reflected in the direction in which the scanning unit 8 is arranged. The dichroic mirror 14G has a property of reflecting only light of a blue component wavelength and transmitting light of other wavelengths. This dichroic mirror 14B is a mirror 14R
The red laser light, which is disposed on the optical path from the dichroic mirror 14G to the scanning unit 8 and is reflected by the mirror 14R and transmitted through the dichroic mirror 14G, and the green laser light reflected by the dichroic mirror 14G, , Dichroic mirror 14
The light passes through B and reaches the scanning unit 8. That is, the light traveling from the dichroic mirror 14B toward the scanning unit 8 is composed of red, green, and blue component laser beams modulated according to image data. As a result, the mirror 14R, the dichroic mirror 14G
14B constitutes a condensing means for condensing the laser light of each color coaxially.

In the light source section 7, the red LD 10
B, when the laser light of each color of R, G, B is emitted from the green SHG laser unit 10G and the blue SHG laser unit 10B, the laser light of each color becomes AOM12R, 12G.
12B, the light is modulated according to the image data corresponding to each dot in the main scanning direction of the photographic paper P, and the light intensity is adjusted according to the image data.
B, mirror 14R and dichroic mirror 14G
The light will be integrally incident on the scanning unit 8 described below via 14B.

In this embodiment, as described above, AOM is used as a configuration for modulating the intensity of laser light of each color component.
Although 12R, 12G, and 12B are used, the present invention is not limited to this. For example, an electro-optic modulator (EO)
M), a configuration may be adopted in which the intensity of laser light is modulated by applying a magneto-optical modulation element (MOM).

(Configuration of Scanning Unit) The scanning unit 8 includes a reflection mirror 16, a cylindrical lens 17, and a polygon mirror 18.
And an fθ lens 20. A cylindrical lens 17 is arranged on an optical axis extending from the reflection mirror 16 to the polygon mirror 18, and an fθ lens 20 is arranged on an optical path extending from the polygon mirror 18 to the printing paper P.

[0086] The reflection mirror 16 includes a light source section 7R, 7G, 7
Mirror 14R and dichroic mirror 14G in B
A member that reflects the red, green, and blue component laser beams reflected at 14B in the direction in which the polygon mirror 18 is disposed. Cylindrical lens 1
Reference numeral 7 denotes a laser beam reflected by the reflection mirror 16,
This is a lens that focuses light on the reflection surface of the polygon mirror 18.

The polygon mirror 18 is a regular polygonal columnar rotating body having a plurality of reflecting surfaces on its side surfaces.
Polygon driver 19 controlled by (see FIG. 5)
Is driven to rotate. By adjusting the rotation speed of the polygon mirror 18, the resolution (the number of dots) of the photographic paper P in the main scanning direction can be adjusted.

The fθ lens 20 is a lens for correcting image distortion near both ends of the scanning surface due to the laser light emitted from the polygon mirror 18 to the photographic paper P. The image distortion near both ends of the scanning plane is caused by the difference in the length of the optical path from the polygon mirror 18 to the printing paper P.

With such a configuration of the scanning unit 8, the R, G, and B laser beams emitted from the light source unit 7 pass through the reflecting mirror 16 and the cylindrical lens 17 to one reflecting surface of the polygon mirror 18. And is reflected by the reflection surface and travels in the photographic paper P direction. When the direction of reflection of the laser light from the polygon mirror 18 changes in the main scanning direction in accordance with the rotation of the polygon mirror 18, the photographic paper P is scanned in the main scanning direction.

At this time, when the reflection of the laser beam on one reflecting surface is completed by the rotation of the polygon mirror 18,
The irradiation of the laser light is transferred to the reflection surface adjacent to the reflection surface, and the reflection direction of the laser light moves in the same range in the main scanning direction.
In other words, immediately after the scanning of one scanning line on the photographic paper P is completed, the laser beam immediately strikes the scanning start point of the next scanning line. Therefore, by exposing while transporting the photographic paper P by the transport unit 9 described later, the photographic paper P is two-dimensionally exposed with almost no time lag in each exposure of the scanning lines adjacent in the sub-scanning direction. It becomes possible.

The light source unit 7 and the scanning unit 8 described above
Emits a light beam (laser light) of an amount corresponding to the image data for each dot arranged in the main scanning direction of the printing paper P, and guides the light beam to the printing paper P by scanning the light beam in the main scanning direction. It constitutes a light beam irradiation means.

In the scanning section 8 described above, if a surface tilt error (an error in which the normal direction of the reflection surface deviates from the normal main scanning surface) occurs on the reflection surface of the polygon mirror 18, the image is printed on the printing paper P. The arrival position of the laser beam greatly changes, and the image quality of the printed image is greatly impaired.

Therefore, in the present embodiment, the laser light reflected by the reflecting mirror 16 by the cylindrical lens 17 is focused on the reflecting surface of the polygon mirror 18 at substantially the center in the sub-scanning direction. The fθ lens 20 and the photographic paper P are arranged so that the laser light reflected from the polygon mirror 18 passes through the fθ lens 20 and then condenses on the photographic paper P again.

With such a configuration, the polygon mirror 1
8 and the printing paper P are optically conjugated to each other, so that even if the light flux is deflected in the sub-scanning direction due to the surface tilt, those light fluxes are reflected on the printing paper P via the fθ lens 20. An image is formed at the same position in the sub-scanning direction. In other words, even if light is emitted from a point on the reflection surface of the polygon mirror 18 in an arbitrary direction in the sub-scanning direction within a certain range, an image is formed on the photographic printing paper P at the same position in the sub-scanning direction. become. Therefore, according to the above configuration, even if the polygon mirror 18 has a surface tilt error, it can be corrected (surface tilt correction).

Further, even if the inclination of each reflecting surface of the polygon mirror 18 varies, the cylindrical lens 17 can be used to adjust the inclination of the reflecting surface of the polygon mirror 18.
By condensing the laser beam almost at the center in the sub-scanning direction, the effect of the variation is minimized,
The reflected light from the polygon mirror 18 can reliably enter the fθ lens 20.

The scanning angle when one line of the photographic paper P is scanned by one reflection surface of the polygon mirror 18 is determined by the number of surfaces of the polygon mirror 18. That is, assuming that the number of surfaces of the polygon mirror 18 is M, the scanning angle is represented by 360 ° / M × 2. In this embodiment,
Since M = 8, the scanning angle is 360 ° / 8 × 2 =
90 °.

As described above, the direction in which the laser light is reflected by the polygon mirror 18 is swung within a range of 90 ° in the main scanning direction via the fθ lens 20 due to the rotation of the polygon mirror 18. Then, 4 of them
The laser beam oscillated in the range of 5 ° is used for exposing the printing paper P. This is because when the photographic paper P is exposed to light obtained through the vicinity of both ends of the fθ lens 20, distortion is likely to occur in the image. Note that the range of 45 ° is a range that spreads symmetrically about the normal line of the photographic paper P as an axis.

The ratio indicating how much of the light oscillated in the range of 90 ° is actually used for scanning the photographic paper P is called an effective scanning period ratio. In the example of the present embodiment, the effective scanning period ratio is 45 ° / 90 ° = １ ／.

The scanning section 8 further includes a synchronization sensor 21A and a mirror 21B in addition to the above configuration. The synchronous sensor 21A and the mirror 21B are provided outside the main scanning range of the laser beam from the polygon mirror 18 to the photographic paper P, respectively. Mirror 21B
Is located at a position immediately outside the main scanning direction when viewed from the polygon mirror 18 toward the exposure (scanning) start point. Therefore, the laser beam reflected from one reflection surface of the polygon mirror 18 first strikes the mirror 21B, and is thereafter provided for exposure in the main scanning direction.

The angle of the reflection surface of the mirror 21B is set so that when the laser light from the polygon mirror 18 strikes the mirror 21B, the light reflected by the mirror 21B enters the synchronization sensor 21A. The length of the optical path from the polygon mirror 18 to the synchronization sensor 21A via the mirror 21B is designed to be substantially equal to the length of the optical path from the polygon mirror 18 to the main scanning start point on the printing paper P. Have been.

The above-mentioned synchronous sensor 21A is a sensor for detecting light.
When a laser beam is incident through the exposure control unit 30 (FIG. 5) at the irradiation timing via the overall control unit 51 described later.
Signal). By monitoring the output from the synchronous sensor 21A, the exposure control unit 30 can accurately grasp the scanning timing according to the width of the photographic paper P to be used.

(Structure of Transport Unit) The transport unit 9 has a configuration including a transport roller 22, a micro step motor 23, a micro step driver 24, and the like. The transport roller 22 is a roller that transports the photographic paper P, and is illustrated in FIG.
In, the photographic paper P is transported in the rotation axis direction (sub-scanning direction) of the polygon mirror.

The micro step motor 23 is a kind of a stepping motor for driving the transport roller 22, and has a feature that vibration is small, that is, transport unevenness is small. Thus, the rotation angle can be controlled very precisely, and the transport position of the photographic paper P in the sub-scanning direction can be precisely controlled.

The micro-step driver 24 controls the rotation of the micro-step motor 23 in order to convey the printing paper P with a predetermined conveying pulse. The overall control unit 51 controls the micro-step driver 24 via the transport system control unit 52 (see FIG. 5) to adjust the rotation speed of the micro-step motor 23 so that the transport speed of the photographic paper P in the sub-scanning direction is adjusted. Is adjusted, and the resolution in the sub-scanning direction is adjusted.

After the exposure of one line in the main scanning direction is completed,
The transport pulse for transporting the photographic paper P until the next line is exposed may be a single pulse or a plurality of pulses. Further, the above-mentioned transport pulse is output from the synchronous sensor 21A.
It may or may not be synchronized with the detection signal from. In short, it is only necessary that the photographic paper P be transported in the sub-scanning direction at a constant speed, and be transported in the sub-scanning direction so as to obtain a desired resolution.

In the systems other than the transport system 9 (for example, the developing unit 3), other motors such as an induction motor are used. However, all the motors for transporting the printing paper P are provided by the micro step motor 23 or the like. Of course, the pulse motor may be used. However, in this case, the printing paper P
Can be performed with higher accuracy, but a control system for driving each of the pulse motors becomes expensive.

The transport section 9 has a position detection sensor (not shown) for detecting the position of the photographic paper P in the sub-scanning direction. The position detection sensor is disposed upstream of the exposure position of the photographic paper P in the sub-scanning direction, detects that the leading or trailing end of the photographic paper P has passed, and transmits the information to the overall control unit 51. Exposure control unit 3
0 is supplied.

(Configuration of Data Supply Unit) Next, the basic configuration of the data supply unit 26 will be described.

As shown in FIG. 5, the data supply unit 26
AOM for driving AOM12R, 12G, 12B
The image data is input to the drivers 15R, 15G, and 15B, and the reference clock generation circuits 27R, 27G, and
27B, data buffers 28R / 28G / 28B, D /
A converter 29R / 29G / 29B, exposure controller 3
0, R component image data storage unit 53R, G component image data storage unit 53G, and B component image data storage unit 53B.

Reference clock generation circuit 27R / 27G / 2
7B is for generating a pixel clock corresponding to each of RGB. The pixel clock is a clock for controlling the timing for sequentially exposing each dot on the photographic paper P, and its frequency is represented by the reciprocal of the time for exposing one dot (pixel) on the photographic paper P. It is. The setting of the frequency of the pixel clock determines how many dots are exposed in the main scanning direction.

Data buffers 28R, 28G, 28B
Is a memory for temporarily storing image data of R, G, and B color components from the R component image data storage unit 53R, the G component image data storage unit 53G, and the B component image data storage unit 53B. Circuit 27R ・ 27G ・
In synchronization with the pixel clock of each color generated at 27B, the D / A converter 29R converts the image data by one pixel.
・ Output to 29G / 29B.

D / A converter 29R / 29G / 29B
Converts the digital image data input from the data buffers 28R, 28G, and 28B into analog data, and outputs the analog data to the AOM drivers 15R, 15G, and 15B.

The exposure control unit 30 controls the reference clock generation circuits 27R, 27G, and 27B. For example, the frequency of each pixel clock generated by the reference clock generation circuits 27R, 27G, 27B is
Exposure control unit 3 so as to be synchronized with the detection signal from 1A.
Adjusted by 0. The exposure control unit 30 includes an R component image data storage unit 53R and a G component image data storage unit 5R.
The timing of reading image data of each color component from the 3G and B component image data storage unit 53B to the data buffers 28R, 28G, and 28B (the same timing for all colors) is also controlled. Exposure unit 6 including exposure control unit 30
The overall operation is controlled by the overall control unit 51.

In the case where the RGB laser light is integrally irradiated on a predetermined pixel of the photographic paper P as in the present embodiment, the same pixel corresponds to the same pixel because the refractive index of the fθ lens 20 is different between RGB. If it is not considered that the irradiation positions of the laser beams of the respective colors on the photographic paper P are shifted from each other, the frequencies of the RGB pixel clocks are all the same, and the same position on the photographic paper P (predetermined pixel ) Can be irradiated with laser beams of three colors RGB. On the other hand, when the above color shift is considered, the exposure control unit 30
However, such a color shift can be eliminated by, for example, changing the frequency of each pixel clock of RGB and making the scan start timings in the main scanning direction different from each other.

Although the configuration shown in FIG. 4 is configured to irradiate the RGB laser light integrally to predetermined pixels of the photographic paper P, for example, the RGB laser light is incident on the polygon mirror 18 through separate optical paths. It is good also as a structure to make it. in this case,
The emission angle of the laser light from the polygon mirror 18 is RGB
Therefore, the photographic printing paper P is irradiated at different positions with the RGB laser light at the same timing. Therefore, in this case, it is necessary for the exposure control unit 30 to adjust each of the RGB pixel clocks so that the RGB laser light corresponding to a predetermined pixel of the photographic paper P is irradiated to the pixel at different timings. Become.

(Structure of Main Part) Next, the structure of the main part of the present invention will be described. In the present invention, the light source unit 7 and the data supply unit 26 are slightly different from the above-described basic configuration. In the following, mainly the light source unit 7R and the corresponding data supply unit 26 will be described.
Light source units 7G and 7B and corresponding data supply unit 2
6 has the same configuration as that described below, and a description thereof will be omitted.

As shown in FIG. 1, in the present invention, AOM1
2R, AOM driver 15R, D / A converter 29R
Is composed of two AOMs 12R ₁ and 12R ₂ (modulation means), AOM drivers 15R ₁ and 15R ₂ (modulation means), and D / A converters 29R ₁ and 29R ₂ (conversion means). The data supply unit 26 further includes an LUT 41 and a separation unit 42 (data separation unit). On the other hand, the light source unit 7R further includes a spectroscope 43 (spectral means), an attenuator 44 (attenuating means), and a light collector 45 (light collecting means). Note that, in the figure, members not directly related to the following description (for example, the lens group 11R, the light control unit 13R,
Illustration of the mirror 14R, the exposure control unit 30, etc.) is omitted.

The LUT 41 converts 8-bit R-component image data, which is input digital image data, into 12-bit R-component image data. The 12-bit image data is data such that when the photographic paper P is exposed based on the 12-bit image data, a color density that is proportional to the 12-bit image data is obtained on the photographic paper P. Therefore, by using the 12-bit image data, it is possible to sufficiently produce a gradation change in the image expressed on the printing paper P.

The separation unit 42 converts the 12-bit image data output from the LUT 41 into a plurality of bit groups (for example, upper A bits and lower B bits (A and B are positive integers)).
And supplies them to the D / A converters 29R ₁ and 29R ₂ respectively. In the present embodiment, for example, A =
4 and B = 8.

Note that the LUT 41 is provided without providing the separation unit 42.
Of 12-bit image data obtained by, while supplying the upper four bits directly D / A converter 29R _1,
Lower 8 bits directly D / A converter 29R can also ₂ to configuration and supplies. In this case, the LUT 41 itself constitutes a data separating unit.

The LUT 41 is provided in the data buffer 28
It may be provided either before or after R (see FIG. 5). FIG. 1 shows an example in which the LUT 41 is provided after the data buffer 28R.

The D / A converters 29R ₁ and 29R ₂
The converter is provided corresponding to each bit group and converts the image data of each bit group into analog data.
/ A conversion is performed. D / A converter 2
The analog signals from 9R ₁ and 29R ₂ are AO
Is supplied to the M driver 15R ₁ · 15R _2.

There are various types of 4-bit and 8-bit D / A converters at the level of commercial products. In particular, an 8-bit D / A converter is a PC5 (FIG. 2).
Monitor), printers for PCs, liquid crystal display devices, and most other devices that represent images.
Its market size is huge. As in the present embodiment, the 12-bit image data is separated into upper 4 bits and lower 8 bits and handled, so that D / D
The A converters 29R ₁ and 29R ₂ do not need to be constituted by expensive ones having a resolution of 12 bits or more.

[0124] AOM driver 15R ₁ · 15R ₂ and AOM12R ₁ · 12R ₂ is provided corresponding to each of the D / A converter 29R ₁ · 29R _2, modulating the laser beam based on the individual analog signals At the same time, the modulated laser light is supplied to the printing paper P. Therefore, D
It can be said that the / A converter 29R ₁ , the AOM driver 15R ₁ and the AOM 12R ₁ are provided corresponding to the upper bits, and the D / A converters 29R ₂ and A
OM driver 15R ₂ and AOM 12R ₂ may be said to be provided corresponding to the lower bits. Further, AOM 12R ₁ constitute a first modulating means, AOM1
2R ₂ constitutes a second modulating means.

The spectroscope 43 is constituted by optical means such as a half mirror, for example, and splits the laser light emitted from the red LD 10R into AOMs 12R ₁ and 12R _2.
Is to be supplied to In the present embodiment, the spectroscope 43
Is adapted to evenly disperse the laser beam from the red LD10R, it is supplied to each AOM12R ₁ · 12R _2.

The attenuator 44 is, for example, an ND (Neutral Dens).
ity) consists of a filter, which attenuates the laser beam emitted from the AOM 12R _2, the AOM (this embodiment is driven on the basis of the image data of the lower bits are provided after the AOM 12R _2). More specifically, the attenuator 44, a laser light obtained through the AOM 12R _2, to attenuate such light amount becomes 2 ^B / 2 ^N.
Note that the above N corresponds to the number of bits of the original image data (a positive integer of 2 or more), and is 12 in the present embodiment. The above B corresponds to the number of lower bits, and is 8 in the present embodiment as described above. That is,
In this embodiment, the attenuator 44, the laser beam emitted from the AOM 12R _2, to attenuate such light amount becomes 2 ^{8/2 12} = 1/16.

An attenuator 44 is provided in front of the AOM 12R ₂ to attenuate the laser beam incident on the AOM 12R _{2 so} that the light quantity becomes 2 ^B / ^2N, and then the AOM 12R ₂
May be supplied.

The light collector 45 is, for example, a half mirror.
AOM12R composed of optical means ₁Out of the
Laser light and the laser light attenuated by the attenuator 44
To guide the scanning unit 8 (for example, the polygon mirror 18)
It is. By concentrating the above laser beams in this way,
The amount of laser light after focusing is the same as the original 12-bit image.
Rays obtained when AOM is modulated based on data
It becomes equal to the amount of the light. This point will be described later.
I do.

When the same red laser light is applied to the polygon mirror 18 through separate optical paths without being focused, the reflection angles of the laser light at the polygon mirror 18 are different. Is applied to different pixels on the photographic paper P, and the original light amount corresponding to the predetermined pixel cannot be obtained. Therefore, by providing the condenser 45 as in the present embodiment and condensing each of the laser beams and applying the laser beam to the polygon mirror 18, the same light amount as the laser beam obtained by the modulation based on the original 12-bit image data is obtained. , The predetermined pixels on the printing paper P can be reliably exposed with the exposure amount corresponding to the image data.

[0130] In the present embodiment, the red LD10R and spectrometer 43 constitute a light beam supply means for supplying a laser beam to individual AOM12R ₁ · 12R _2.

Next, the operation of the light source unit 7R having the above configuration will be described.

First, the 8-bit R component image data is LU
The data is converted into 12-bit image data by T41. Here, assuming that, for example, “111011010011” has been obtained as the converted 12-bit image data, the separation unit 42 determines that the 12-bit image data is “1110”, which is the upper 4 bits, and lower 8 bits. It is separated into “11010011”. And the top four
Bit image data is supplied to the D / A converter 29R _1, lower 8 bits of the image data is D / A converter 2
It is supplied to the 9R _2. D / A converter 29R ₁・ 29
In R ₂ , each input data is converted into an analog signal and supplied to the AOM drivers 15R ₁ and 15R ₂ .

[0133] On the other hand, the laser beam emitted from the red LD10R is split into two light equal amount of light by the spectroscope 43, respectively incident on the AOM 12R ₁ · 12R _2. In AOM driver 15R ₁ · 15R _2, the high-frequency signal is generated based on the analog signal, AOM 12R
_{In 1} · 12R ₂ , the laser light is modulated based on each high-frequency signal. As a result, from the AOM12R _1, the top four
Is the amount of light the laser light emission of corresponding to the image data bit from the AOM 12R _2, so that the laser light quantity corresponding to the lower 8 bits of the image data is emitted.

At this time, the light amounts P ₁ and P ₂ of the laser beams emitted from the respective AOMs 12R ₁ and 12R ₂ by the modulation by the AOMs 12R ₁ and 12R ₂ are expressed by the following equations. However, the light source light amount in the red LD 10R is 2 ¹² × 2.

P₁= ｛(2^Three+2^Two+2¹) / 2^Four｝ × (2¹²× 2) × 1/2 = 3584 P_Two= ｛(2⁷+2⁶+2^Four+2¹+2⁰) / 2⁸｝ × (2¹²× 2) × 1/2 = 3376 Next, AOM12R_TwoLaser light emitted from the
The light is attenuated by the detector 44 so that the light amount becomes 1/16.
And the light amount P of the laser light emitted from the attenuator 44 _Two’
Is as follows.

P ₂ ′ = 3376/16 = 211 Therefore, the light amount P finally obtained by the light collector 45
Is as follows.

P = P ₁ + P ₂ ′ = 3584 + 211 = 3795 By the way, the AO is performed using the 12-bit image data as it is.
Assuming that the laser light is modulated by M, the light quantity Q is
It looks like this: However, the light source light amount is 2 ¹² .

Q = {(2 ¹¹ +2 ¹⁰ +2 ⁹ +2 ⁸ +2 ⁷ +2 ⁶ +2 ⁴ +2 ¹ +2 ⁰ ) / 2 ¹² } × 2 ¹² = 3795 Therefore, although the original light source light amount setting is different, P
= Q, and it becomes possible to expose the photographic paper P with the same amount of light as when the laser light is modulated based on the 12-bit image data.

As described above, the present invention provides a 12-bit image.
Divides image data into multiple bit groups and supports each bit group
AOM12R₁・ 12R_TwoChange the laser light separately
AOM12R₁・ 12R_TwoCorresponding to
AOM driver 15R provided₁・ 15R_TwoTo Ana
D / A converter 29R for supplying log data ₁
・ 29R_TwoFor 4 bits and 8 bits respectively
It can be composed of things. 4-bit compatible and 8-bit
There are a lot of D / A converters for commercial products at the market level
Therefore, compared to a 12-bit D / A converter
D / A conversion at high speed is possible because of the small number of bits.
And inexpensive.

Therefore, according to the present invention, a high-speed and low-cost commercially available D / A converter can be used without using a 12-bit D / A converter.
It is possible to realize the gradation expression by the 2-bit image data on the printing paper P. Also, it can be said that even if a D / A converter compatible with 4-bit and 8-bit is used, it is possible to reproduce an image having a gradation property higher than the resolution.

In the present invention, since the laser beam is divided into two optical paths and the laser beam is modulated based on each of the upper bit and the lower bit, the light source light quantity can be kept constant. This makes it possible to configure the light source with a light source whose emission light amount cannot be adjusted at high speed, and when the solid-state laser is used as the G or B light source as in the present invention, the above-described configuration is used. Will be very effective. That is, even when a solid-state laser is used as a light source as in the present invention, the above-described effects of the present invention can be reliably obtained.

Further, in this embodiment, one light source can be used for RGB, so that an increase in the price of the apparatus can be suppressed as compared with the structure of a second embodiment described later in which a plurality of light sources are provided for each of RGB. be able to. Particularly, for G and B, an expensive solid-state laser is used, so that the effect is extremely high.

In the present embodiment, the spectroscope 43 is
In the configuration to evenly split the laser light from the red LD10R
As described above, for example, the AOM1
2R ₁・ 12R_TwoThe ratio of the amount of light supplied to the¹²: 2
⁸= 2^Four: From the red LD10R so that
The light may be split. In this case, the above reduction
The attenuator 44 can be dispensed with, simplifying the configuration of the device
can do. In other words, the spectroscope 43 uses the AOM 12
R₁・ 12R_TwoThe light intensity ratio of the laser beam toward ^N: 2^B
The laser light from the red LD 10R so that
Then, it can be said that the above effects can be obtained.

Also, for example, AOM12R ₁・ 12R ₂
The spectroscope 43 splits the laser light from the red LD 10R so that the ratio of the amount of light supplied to the red LD 10R becomes 2: 1.
By setting, only by 1/2 ⁸ attenuated by the attenuator 44 of laser light obtained through the AOM 12R _2, the source 1
A 2-bit image can be reproduced on the printing paper P.
That is, if a and b are positive integers, the spectrometer 43
But the laser beam and the AOM 12R ₂ toward the AOM 12R ₁
2 is the light amount ratio between the laser light directed to ^a: so that 2 ^b, when that splits the laser beam from the red LD10R, attenuator 44, laser emitted from the laser light or AOM 12R ₂ incident on the AOM 12R ₂ Light, light amount 2 ^B
/ 2 ^{N- (ab)} .

In the present embodiment, a D / A converter, an AOM driver, an AOM
Is twice as large as the basic configuration of FIG. 4, and the spectroscope 43, the attenuator 44, and the condenser 45 are required. Therefore, the increase in the number of parts as compared with the basic configuration may cause a rise in the price of the apparatus. The effect that can be realized at high speed by using the / A converter is greater.

[0146] In this described embodiment, the D / A converter 29R ₁ in those four bits corresponding, may be made up of the 8-bit correspondence. In this case, it is only necessary to use a part (for 4 bits) of the 8-bit D / A converter.

Further, in the present embodiment, the separation section 42 is
Although the example in which the bit image data is divided into upper 4 bits and lower 8 bits has been described, for example, the same effect as in the present embodiment can be obtained by dividing the upper 6 bits and lower 6 bits. In this case, D / A
6 the number of bits from 8 bits to be handled by the converter 29R ₁
Becomes smaller as the bit, as a D / A converter 29R _1, it is possible to use a more fast conversion speed, it is possible to expose the printing paper P at a high speed.

If a 6-bit D / A converter is not readily available, an 8-bit D / A converter may be easily used to use only the 6 bits. In this case, although the conversion speed does not change, the linearity is improved, and an improvement in image quality can be expected.

Also, in the present embodiment, the LUT 41
The case where the bit image data is converted to the 12-bit image data has been described. However, if at least 10-bit image data can be obtained, the photographic paper P can be colored at a density proportional to the image data. . In this case, the 10-bit image data may be separated by the separation unit 42 into, for example, upper 4 bits and lower 6 bits.

Regardless of the type of photographic paper P, if any photographic paper P has similar coloring characteristics, it is theoretically possible to obtain a full-color image using 12-bit image data. Can be. Note that the above full-color image generally has a BGR of 0 (black) to 2
55 refers to 2 ⁸ × 2 ⁸ × 2 ⁸ ≒ 1677 million colors images in case of 256 gray scales (2 ⁸ gradations) to (white).

However, in reality, the characteristics of the photographic paper P are as follows.
It differs depending on the manufacturer, even the same manufacturer varies depending on the type (sensitivity), and the lot (production time)
Also depends on If it is considered that such a difference in the characteristics of the photographic paper P is absorbed by the LUT 41, the LUT 41
In this case, it is desirable to convert 8-bit image data to 12-bit or more (for example, 14-bit or 16-bit) image data. Further, in the D / A converter, bit loss of image data may occur due to noise of an electric signal. By converting the bit number into 12 bits or more in the LUT 41, such bit loss can be prevented by the LUT.
At 41 can be absorbed.

Further, in the present embodiment, the separation unit 42
The image data converted by the UT 41 is converted into upper bits and
The case where the lower bits are separated into two bits has been described.
It goes beyond this separation. For example, LUT41
If 24-bit image data is obtained in
42, upper 8 bits, middle 8 bits, lower 8 bits
It may be divided into three. In this case,
A, corresponding to each of the
OM is provided, and the light obtained through each AOM
The quantity ratio is 2 from the AOM corresponding to the upper bit.^{twenty four}:
2¹⁶: 2⁸= 2 ¹⁶: 2⁸: 1 to 8
Out of AOM corresponding to the bit and lower 8 bits
May be attenuated. The same considerations as above
In this manner, the input image data is divided into four or more
It is also possible to adopt a configuration in which they are separated from each other.

By the way, in the optical path from the red LD 10R to the printing paper P, for example, when the laser light is slightly attenuated at the time of spectroscopy by the spectroscope 43, the amount of the laser light finally reaching the printing paper P is reduced. May decrease. However, in this case, by reducing the degree of attenuation of the laser light in the attenuator 44, it is possible to compensate for the amount of light that decreases due to the attenuation in the optical system. That is,
If take into account the attenuation of the optical system in the course progression of the laser beam, AOM12R ₁ · AOM12R 2 light intensity ratio of laser light obtained through the ₂ finally ^N: such that 2 ^B, the attenuator 44 What is necessary is just to set the degree of attenuation in.
At this time, the attenuation ratio of the attenuator 44 is 2 in this embodiment.
^B / 2 slightly smaller ratio than ^N (e.g., approximately 2 ^B / 2
^N ) can be assumed. By setting such an attenuation ratio, even if the laser light causes optical attenuation in the optical path, the light amount ratio of 2 ^N : 2 ^B is finally obtained, and the original N-bit image data is obtained. Can be reliably reproduced.

On the other hand, as described in this embodiment, the spectroscope 43 evenly splits the laser light from the red LD 10R, and the attenuator 44 outputs the laser light emitted from the AOM 12R ₂ (or the laser light incident on the AOM 12R _2). Light) is attenuated so that the light amount becomes ^2B / ^2N ,
If the optical attenuation does not occur in the optical path of the laser light,
A laser light obtained through the AOM 12R _1, AOM1
The light amount ratio with the laser light obtained through 2R ₂ is 2 ^N : 2
^B. Accordingly, when the optical attenuation does not occur, a light beam having a light amount corresponding to the original N-bit image data is reliably obtained, and an image corresponding to the original N-bit image data is reliably formed on the photosensitive material. Can be reproduced.

As described above, the present invention can be applied to the AO with or without the optical attenuation in the optical path of the laser beam.
The attenuator 44 controls the AOM 12 so that the light amount ratio of the laser light obtained through the M12R ₁ · AOM 12R ₂ becomes a ratio capable of reproducing an image corresponding to the original N-bit image data.
It can be said that the laser beam emitted from the R ₂ (or laser light incident on AOM 12R ₂₎ is configured to attenuate.

Even if optical attenuation of the laser light actually occurs, if the degree of the attenuation is small, the attenuator 44 attenuates the laser light so that the light amount becomes 2 ^B / ^2N. Accordingly, an image close to the image corresponding to the original N-bit image data can be reproduced on the photosensitive material.

For example, Japanese Patent Publication No. 5-10867 discloses that 12-bit digital image data is divided into upper bits and lower bits, and the magnitude of the analog output is determined based on the upper bits. A control method of an exposure light source for performing time width control corresponding to the above is disclosed.
Therefore, it can be said that the above-mentioned publication and the present invention have a common point in that the digital image data is divided into upper and lower parts to use a D / A converter having a small number of bits.

However, the above publication discloses a configuration in which a desired amount of light is obtained by changing the amount of light emitted from the light source itself.
As in the present invention, this is not a configuration in which a desired light amount is obtained by keeping the amount of light emitted from the light source constant, dividing the optical path of the laser light into two, and separately modulating each laser light. That is, the present invention is completely different from the above publication in the configuration itself for obtaining a desired light quantity.

Further, the present invention employs the configuration described in the present embodiment because the exposure apparatus of the present invention uses G or B
This is because a solid-state laser that takes a long time for internal oscillation is used as the light source, and the amount of emitted light itself cannot be adjusted at a high speed by the light source as described in the above publication. for that reason,
Instead of keeping the light source light amount constant, the light amount is adjusted in each AOM. In the present invention, a solid light source having a constant emission light amount is used as a G or B light source by making the emission light amount from the light source constant, dividing the optical path of the laser light into two, and modulating each laser light separately. Since a laser can be used, it is possible to realize an exposure apparatus that performs exposure using laser light of each color, and it is possible to reliably obtain the above-described effects of the present invention also in such an exposure apparatus.

In the above publication, since a semiconductor light source capable of adjusting the amount of emitted light is assumed, it is not necessary to re-modulate the emitted laser light, and it is not necessary to divide the laser light into separate optical paths. Therefore, in the above-mentioned publication, the configuration of the present invention for modulating laser light with separate optical paths cannot be easily conceived from the configuration of the above publication, as long as a semiconductor light source capable of adjusting the amount of emitted light is used as the light source.

The above publication in which the light source light amount is adjusted by time control is an area gradation method in which gradation expression is performed by changing the area of a light irradiation portion in a predetermined pixel.
The image quality is inferior to that of the present invention in which the modulated laser light is uniformly applied to the entire surface of the predetermined pixel. In other words, the method disclosed in the above publication can obtain only the resolution and the pseudo one of the present invention,
In order to obtain the same resolution as that of the present invention, special measures such as increasing the frequency of the pixel clock are required.

[Embodiment 2] Another embodiment of the present invention will be described below with reference to the drawings. For convenience of description, the same components as those of the first embodiment are denoted by the same reference numerals, and description thereof is omitted. Also, in the present embodiment, the light source unit 7R will be mainly described. However, the light source units 7G and 7B have exactly the same configuration as the light source unit 7R, and the description thereof will be omitted.

In the present embodiment, as shown in FIG. 6, in the configuration of the first embodiment, instead of removing the spectroscope 43 and the attenuator 44 shown in FIG. _1, red in response to the individual and AOM 12R ₂ which is driven in response to the lower B bits LD1
The configuration is such that 0R ₁ · 10R ₂ (first light source / second light source) is provided. And red LD10R ₁・ 10R
The ratio of the light amounts of the laser beams emitted from ₂ is set to be 2 ^N : 2 ^B. Note that the above N corresponds to the number of bits of the original image data.

[0164] That is, in correspondence with the AOM 12R ₁ · 12R _2, different emission light intensity red LD10R ₁ · 10R ₂
Is provided, the spectroscope 43 and the attenuator 44 used in the first embodiment are not required.

In this configuration, the LUT 41
For example, the same 12-bit image data as in the first embodiment,
That is, "111011010011" was obtained and separated.
In the section 42, the above 12-bit image data is the upper 4 bits
And the lower 8 bits, AOM12R
₁・ 12R_TwoAmount of laser light P emitted from₁・ P _Two
Are represented as follows. However, red LD
10R₁2 light source¹²And red LD10R_TwoLight of
Source light intensity 2⁸And

P ₁ = {(2 ³ +2 ² +2 ¹ ) / 2 ⁴ } × 2 ¹² = 3584 P ₂ = {(2 ⁷ +2 ⁶ +2 ⁴ +2 ¹ +2 ⁰ ) / 2 ⁸ } × 2 ⁸ = 211 , The light amount P finally obtained by the light collector 45
Is as follows.

P = P ₁ + P ₂ = 3584 + 211 = 3795 By the way, the AO is performed using the 12-bit image data as it is.
The light quantity Q when the laser light is modulated by M is 3 by the same calculation method as in the first embodiment, assuming that the light source light quantity is 2 ^12.
795.

Therefore, P = Q, and even when light sources having different emission light amounts are provided corresponding to the upper bits and the lower bits as in the present embodiment, the laser light is emitted based on the 12-bit image data. The same result as in the case of modulation can be obtained. Therefore, according to the configuration of the present embodiment, the same effect as that of the first embodiment can be obtained.

The optical system during the progress of the laser beam
AOM12R if we take into account the attenuation at₁・ AO
M12R_TwoThe light intensity ratio of the laser light obtained through
To 2 ^N: 2^BRed LD10R₁・ 10R
_TwoMay be set. Outgoing light at this time
The quantitative ratio is, for example, approximately 2^N: 2^BCan be assumed
Wear. By setting the output light amount ratio in this way, the laser
Even if the laser light causes optical attenuation in the optical path,
Typically, 2^N: 2^BOf the original N-bit image
It is possible to reliably reproduce the image corresponding to the image data
Become.

On the other hand, as described in this embodiment,
Light intensity ratio of 2^N: 2^BIf the configuration is set to
If the optical attenuation does not occur in the optical path of
2R ₁Laser light obtained through the AOM12R_TwoTo
The light amount ratio with the laser light obtained through^N: 2
^BIt is. As a result, when the above optical attenuation does not occur
Light beam corresponding to the original N-bit image data
The original N-bit image data
The image can be reliably reproduced on the photosensitive material.

As described above, according to the present invention, AO can be performed with or without optical attenuation in the optical path of laser light.
The red LDs 10R ₁ · 10 are set so that the light amount ratio of the laser light obtained through the M12R ₁ · AOM 12R ₂ is a ratio capable of reproducing an image corresponding to the original N-bit image data.
It can be said that the configuration is such that the ratio of the amount of laser light emitted from R ₂ is set.

Even if the optical attenuation of the laser light actually occurs, if the degree of the attenuation is small, even if the emission light amount ratio is set to 2 ^N : 2 ^B , the original N bits An image close to the image corresponding to the image data can be reproduced on the photosensitive material.

The configuration of the present embodiment is similar to that of the light source units 7G
When applied to B, it is necessary to prepare two expensive solid-state lasers for G and B, and there is a concern that the price of the exposure apparatus will increase. Therefore, for example, by adopting the configuration of the present embodiment for R and adopting the configuration of the first embodiment for G and B, it is possible to suppress an increase in the price of the apparatus to some extent.

The exposure method of the present invention described in each of the above embodiments can also be expressed as the following first to eighth image forming methods.

In the first image forming method, image information having a gradation is decomposed into S (where S is a positive integer of 2 or more) bit groups, and S laser beams having a predetermined light amount are divided into bit groups. This is a method of condensing S modulated laser lights modulated by the method and forming an image.

According to a second image forming method, in the first image forming method, image information having a gradation is decomposed into upper bits and lower bits, and a first laser beam having a predetermined light amount is converted into upper bits. A modulated first modulated laser beam and a second laser beam having a predetermined amount of light modulated by lower bits.
And the modulated laser light is condensed to form an image.

In the third image forming method, image information having a gradation is decomposed into S (S is a positive integer of 2 or more) bit groups, and a predetermined amount of laser light is divided by a predetermined amount of light. This is a method of forming an image by splitting into S light beams, condensing S modulated laser light beams obtained by modulating the split laser light by a bit group, and forming an image.

A fourth image forming method is the same as the third image forming method, except that image information having a gradation is decomposed into upper bits and lower bits, and a predetermined amount of laser light is separated by a predetermined light amount ratio. Forming an image by condensing a first modulated laser beam obtained by modulating the split first laser beam with the upper bits and a second modulated laser beam obtained by modulating the split second laser beam by the lower bits. How to

The fifth image forming method is a method of setting the ratio of the S types of light amounts in the first or third image forming method to a ratio at which the original image can be reproduced.

The sixth image forming method is the same as the first or third image forming method, except that the ratio of the S types of light amounts is a ratio that can reproduce the original image, and the optical attenuation is considered. This is a method of setting the ratio so that an image can be reproduced.

In the seventh image forming method, when the number of bits of the original image information is N and the number of lower bits is B in the fourth image forming method, the first laser light and the second laser light are used. the spectral ratio between 2 ^N: a method for the 2 ^B.

The eighth image forming method is similar to the fourth image forming method.
In the method, the number of bits of the original image information is N,
Let B be the first laser light and the second laser
The spectral ratio with the light is roughly 2^N: 2^BAnd optical
Taking the attenuation into account, 2^N: 2 ^BIt is a method.

[0183]

According to the first aspect of the present invention, as described above, when N is a positive integer of 2 or more, the data separating means separates the N-bit image data into a plurality of bit groups. A plurality of conversion means provided corresponding to the individual bit groups and converting the image data of each bit group into analog data; and a plurality of conversion means provided corresponding to the individual conversion means and modulating the light beam based on the analog data In addition, a configuration is provided in which a plurality of modulating means for supplying a modulated light beam to a photosensitive material and a light beam supplying means for supplying a light beam to each modulating means are provided.

Therefore, since the original N bits are divided into a plurality of bit groups and the light beams are separately modulated by the modulating means corresponding to each bit group, each converting means corresponding to each modulating means is It can be configured with one corresponding to a smaller number of bits than the original N bits. For example, since there are many 4-bit or 8-bit conversion means at the level of a commercially available product, high-speed conversion is possible because the number of bits is smaller than that of the original N-bit conversion means, and the cost is low. It is.

Therefore, the gradation expression by the original N-bit image data can be realized on the photosensitive material by using the high-speed and low-cost conversion means of a commercial product without using the original N-bit conversion means. This has the effect of making it possible to

In the above configuration, since the light beam is modulated by each modulation means, the light amount of the light beam supplied by the light beam supply means may always be kept constant. This makes it possible to configure the light beam supply means with a light amount that cannot be adjusted at high speed in accordance with, for example, image data (for example, one including a solid-state laser). The effect that the degree of freedom of configuration can be increased is also exhibited.

In the exposure apparatus according to the second aspect of the present invention, as described above, in the configuration of the first aspect, the light beam supply means includes: a light source for emitting a light beam; And a spectroscopic means for supplying the light to the means.

Therefore, since the light beam emitted from the light source is split by the spectroscopic means and supplied to each modulation means, a single light source can be used as the light source. This has the effect that the light source portion can be configured at a lower cost, for example, as compared with a configuration in which a plurality of light sources are provided corresponding to each modulation unit.

In the exposure apparatus according to the third aspect of the present invention, as described above, when A and B are positive integers in the configuration of the second aspect, the data separating means converts the N-bit image data into the upper A bits. A light beam obtained through a first modulating means as a modulating means corresponding to the upper A bits, and a modulating means corresponding to the lower B bits. Second as
The light incident on the second modulating means is such that the light quantity ratio with the light beam obtained through the modulating means is such that an image corresponding to the original N-bit image data can be reproduced on the photosensitive material. The light emitting device further includes an attenuation unit that attenuates the beam or the light beam emitted from the second modulation unit.

Therefore, the attenuating means attenuates the light beam incident on the second modulating means or the light beam emitted from the second modulating means so as to obtain the above-mentioned light amount ratio. With the upper A bit and lower B
Even if the light beam is modulated separately for each bit, the original N
A light beam having a light amount corresponding to the bit image data can be reliably obtained. As a result, by supplying each light beam modulated based on the image data of each bit group to the photosensitive material, an image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material. This has the effect of becoming

As described above, in the exposure apparatus according to the fourth aspect of the present invention, in the configuration of the third aspect, the light amount ratio is determined in the optical path from the light beam supply means to the photosensitive material.
The ratio is such that an image corresponding to the original N-bit image data can be reproduced on the photosensitive material in consideration of the optical attenuation of the light beam other than the attenuating means.

Therefore, even when optical attenuation occurs in the optical path of the light beam, an effect that the image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material can be obtained. .

As described above, in the exposure apparatus according to the fifth aspect of the present invention, if A and B are positive integers in the configuration of the second aspect, the data separation means converts the N-bit image data into the upper A And a light beam directed to a first modulating means as a modulating means corresponding to the upper A bits and a modulating signal corresponding to the lower B bits. The light amount ratio with respect to the light beam directed to the second modulating means is 2 ^N : 2
^In this configuration, the light beam from the light source is split so that ^B is obtained.

Therefore, the light traveling toward the first modulating means and the second
The light amount ratio to the light going to the modulation means is 2 ^N: 2^BSo that
In addition, since the light splitting means splits the light beam from the light source, N
Bit image data into upper A bits and lower B bits
Even if the light beam is divided and modulated separately, the original N-bit image
It is possible to reliably obtain a light beam with the amount of light corresponding to the image data.
it can. As a result, based on the image data of each bit group,
By supplying each modulated light beam to a photosensitive material,
The image corresponding to the original N-bit image data
The effect is that it is possible to reliably reproduce the
I do.

Further, in the above configuration, the original N-bit image can be reproduced on the photosensitive material by dispersing and modulating the light beam at the spectral ratio.
Alternatively, there is no need to provide an attenuating means for adjusting the amount of light as in the configuration of 4. Thereby, the effect that the configuration of the device can be simplified can be achieved.

In the exposure apparatus according to the sixth aspect of the present invention, if a and b are positive integers in the configuration of the third aspect, the spectroscopy unit performs the light beam toward the first modulation unit. and light quantity ratio between the light beam directed to said second modulating means 2 ^a: as a 2 ^b, are those that splits light beam from said light source, said attenuating means is incident on the second modulating means And the light beam emitted from the second modulating means is attenuated so that the light quantity becomes 2 ^B / 2 ^{N- (ab)} .

Therefore, by setting the spectral ratio in the spectral means as described above and the attenuation ratio in the attenuating means as described above, the final light amount of the first light beam and the second light beam is obtained. The ratio is such that the original N-bit image can be reproduced on the photosensitive material. As a result, by supplying the first light beam and the second light beam to the photosensitive material,
This has the effect that an image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material.

According to a seventh aspect of the present invention, as described above, in the configuration of the third aspect, the dispersing unit disperses the light beam from the light source so that the light amount is uniform. The attenuating means is configured to attenuate the light beam incident on the second modulating means or the light beam emitted from the second modulating means so that the light amount becomes 2 ^B / ^2N .

Therefore, when optical attenuation of the light beam in the optical path does not occur, a light beam having an amount of light corresponding to the original N-bit image data is obtained by the above-described attenuation of the attenuating means. This has the effect that an image corresponding to the data can be reliably reproduced on the photosensitive material.

[0200] In the exposure apparatus according to the eighth aspect of the present invention, as described above, in the configuration of the first aspect, the light beam supply means includes a light source for emitting a light beam corresponding to each modulating means. Configuration.

Therefore, the light amount of the light beam supplied to each modulation means can be adjusted for each light source. Thereby, in order to obtain the light amount corresponding to the original N-bit image data, a member for adjusting the light amount ratio of the light beam obtained through each modulation unit (for example, the light obtained through a predetermined modulation unit) (A means for attenuating the beam).

In the exposure apparatus according to the ninth aspect of the present invention, when A and B are positive integers in the configuration of the eighth aspect, the data separating means converts the N-bit image data into the upper A A first light source serving as a light source for supplying a light beam to a modulating means corresponding to the upper A bits, and a modulating means corresponding to the lower B bits. The ratio of the amount of emitted light to the second light source as a light source for supplying a light beam to the light source is set such that an image corresponding to the original N-bit image data can be reproduced on the photosensitive material. Configuration.

Therefore, since the ratio of the amount of emitted light is set as described above, even if the light beam is modulated by dividing the N-bit image data into upper A bits and lower B bits separately, Light beam corresponding to the N-bit image data can be reliably obtained. As a result, by supplying each light beam modulated based on the image data of each bit group to the photosensitive material, an image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material. This has the effect of becoming

In the exposure apparatus according to the tenth aspect of the present invention, as described above, in the configuration of the ninth aspect, the ratio of the amount of emitted light is determined by adjusting the ratio of the light beam in the optical path from the light beam supply means to the photosensitive material. The ratio is set so that an image corresponding to the original N-bit image data can be reproduced on the photosensitive material in consideration of the dynamic attenuation.

Therefore, by taking into account the optical attenuation of the light beam in the optical path, the above-mentioned ratio of emitted light can be reproduced on a photosensitive material by an image corresponding to the original N-bit image data (for example, approximately 2 ^N : ^2B ), it is possible to reliably reproduce an image corresponding to the original N-bit image data on the photosensitive material even when optical attenuation occurs in the optical path of the light beam. This has the effect.

As described above, in the exposure apparatus according to the eleventh aspect, in the configuration of the ninth aspect, the ratio of the amount of emitted light is set to 2 ^N : 2 ^B.

Therefore, when optical attenuation of the light beam in the optical path does not occur, setting of the above-mentioned emission light amount ratio allows
The light beam having the light amount corresponding to the original N-bit image data is obtained, and the image corresponding to the original N-bit image data can be reliably reproduced on the photosensitive material.

In the exposure apparatus according to the twelfth aspect of the present invention, as described above, in any one of the first to eleventh aspects, the light beam obtained through each modulating means is condensed and supplied to the photosensitive material. This is a configuration further including a light collecting means.

Therefore, it is possible to collectively irradiate the same pixel of the photosensitive material with the light beam obtained through each modulation means at the same timing. As a result, even when a plurality of modulating units are used, it is possible to realize the same exposure as the case where the exposure is performed based on the original N-bit image data.

A photographic processing apparatus according to a thirteenth aspect of the present invention
As described above, the exposure apparatus according to any one of the first to twelfth aspects is provided with the developing unit that develops an image formed on a photosensitive material by the exposure apparatus.

According to the exposure apparatus of any one of claims 1 to 12, expensive N bits (for example, 12 bits)
An image corresponding to the original N-bit image data can be printed on the photosensitive material without using a corresponding conversion unit. Therefore, by realizing a photo processing apparatus at low cost with such an exposure apparatus and a developing unit, it is possible to provide a customer with a rich tone expression at low cost.

According to the exposure method of the fourteenth aspect of the present invention, as described above, when N is a positive integer, the step of separating N-bit image data into a plurality of bit groups; Converting the light beam into analog data by individual conversion means, and modulating the light beam supplied from the light beam supply means to each modulation means based on the individual analog data and supplying the modulated light beam to the photosensitive material. This is the configuration.

Therefore, since the original N bits are divided into a plurality of bit groups and the light beams are separately modulated by the modulating means corresponding to each bit group, each converting means corresponding to each modulating means is It can be configured with one corresponding to a smaller number of bits than the original N bits. For example, since there are many 4-bit or 8-bit conversion means at the level of a commercially available product, high-speed conversion is possible because the number of bits is smaller than that of the original N-bit conversion means, and the cost is low. It is.

Therefore, the gradation expression by the original N-bit image data can be realized on the photosensitive material by using a high-speed and low-cost commercial-level conversion means without using the original N-bit conversion means. This has the effect of making it possible to

Further, in the above configuration, since the light beam is modulated by each modulation means, the light quantity of the light beam supplied to each modulation means may always be constant. This makes it possible to configure the light beam supply means even if the amount of emitted light cannot be adjusted at high speed in accordance with, for example, image data (for example, one including a solid-state laser). In addition, there is an effect that the degree of freedom of configuration can be increased.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a schematic configuration of a main part of an exposure unit provided in a photographic processing apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a schematic configuration of the photographic processing apparatus.

FIG. 3 is an explanatory diagram showing a schematic configuration of a printing unit of the photographic processing apparatus.

FIG. 4 is an explanatory diagram illustrating a schematic configuration of a light source unit, a scanning unit, and a transport unit in the exposure unit.

FIG. 5 is a block diagram showing a basic configuration of a data input unit in the exposure unit.

FIG. 6 is a block diagram illustrating a schematic configuration of a main part of an exposure unit provided in a photographic processing apparatus according to another embodiment of the present invention.

FIG. 7 is a graph showing a relationship between 8-bit image data and color development characteristics of photographic paper.

[Explanation of symbols]

3 Developing section 6 Exposure section (exposure device) 10R red LD (light beam supply means, light source) 10R ₁ red LD (light beam supply means, light source, first light source) 10R ₂ red LD (light beam supply means, light source, second light source) 12R ₁ AOM (modulating means, first modulating means) 12R ₂ AOM (modulating means, second modulating means) 15R ₁ AOM driver (modulating means, first modulating means) 15R ₂ AOM driver (modulation means, 29R ₁ D / A converter (conversion means) 29R ₂ D / A converter (conversion means) 42 Separation unit (data separation means) 43 Spectroscope (light beam supply means, spectral means) 44 Attenuator (attenuation) Means) 45 Light collector (light collecting means) P Photographic paper (photosensitive material)

Claims (14)

[Claims] When N is a positive integer of 2 or more, a data separating means for separating N-bit image data into a plurality of bit groups is provided corresponding to each bit group. A plurality of conversion means for converting image data into analog data; and a plurality of modulation means provided corresponding to the individual conversion means for modulating a light beam based on the analog data and supplying the modulated light beam to a photosensitive material. And an optical beam supply unit for supplying a light beam to each of the modulation units. 2. The light beam supply means according to claim 1, wherein said light beam supply means includes a light source for emitting a light beam, and a light splitting means for splitting said light beam and supplying it to each modulation means. Exposure equipment. 3. If A and B are positive integers, the data separating means separates the N-bit image data into upper A-bit image data and lower B-bit image data. The light quantity ratio between the light beam obtained through the first modulating means as the modulating means corresponding to the bit and the light beam obtained through the second modulating means as the modulating means corresponding to the lower B bits is equal to the original light amount. The ratio is such that an image corresponding to N-bit image data can be reproduced on a photosensitive material.
3. The exposure apparatus according to claim 2, further comprising an attenuator for attenuating a light beam incident on the second modulator or a light beam emitted from the second modulator. 4. The light amount ratio corresponds to the original N-bit image data in consideration of the optical attenuation of a light beam other than the attenuating means in the optical path from the light beam supplying means to the photosensitive material. The exposure apparatus according to claim 3, wherein the ratio is such that an image can be reproduced on a photosensitive material. 5. When A and B are positive integers, said data separating means separates N-bit image data into upper A-bit image data and lower B-bit image data. The light amount ratio of the light beam directed to the first modulation means as the modulation means corresponding to the upper A bits and the light beam directed to the second modulation means as the modulation means corresponding to the lower B bits is 2 ^N : 2 ^B. The exposure apparatus according to claim 2, wherein the light beam from the light source is split so that 6. If a and b are positive integers, the spectroscopy unit may be configured to connect the light beam toward the first modulation unit with the second light unit.
Light amount ratio is 2 ^a of the light beam towards the modulation means: as a 2 ^b, are those that splits light beam from said light source, said attenuating means, the light beam incident on the second modulating means or the light beam emitted from the second modulating means, an exposure apparatus according to claim 3, the light amount is equal to or attenuate so that ^{2 B / 2 N- (ab)} . 7. The spectral means for spectrally dispersing a light beam from the light source so that the light amount becomes uniform, and the attenuating means comprises a light beam incident on the second modulating means or the second modulating means. 4. The exposure apparatus according to claim 3, wherein the light beam emitted from the means is attenuated so that the light amount becomes ^2B / ^2N . 8. An exposure apparatus according to claim 1, wherein said light beam supply means includes a light source for emitting a light beam corresponding to each of the modulation means. 9. When A and B are positive integers, the data separating means separates the N-bit image data into upper A-bit image data and lower B-bit image data. The ratio of the amount of emitted light between the first light source as a light source that supplies a light beam to the modulation unit corresponding to the bit and the second light source as a light source that supplies a light beam to the modulation unit corresponding to the lower B bits is: 9. The exposure apparatus according to claim 8, wherein the ratio is set so that an image corresponding to the original N-bit image data can be reproduced on a photosensitive material. 10. The ratio of the amount of emitted light is determined by taking into account the optical attenuation of the light beam in the optical path from the light beam supply means to the photosensitive material and forming an image corresponding to the original N-bit image data on the photosensitive material. The exposure apparatus according to claim 9, wherein the ratio is set to be reproducible. 11. The exposure apparatus according to claim 9, wherein the ratio of the amount of emitted light is set to 2 ^N : 2 ^B. 12. The exposure according to claim 1, further comprising a light condensing means for condensing a light beam obtained through each modulation means and supplying the light beam to a photosensitive material. apparatus. 13. A photographic processing apparatus comprising: the exposure apparatus according to claim 1; and a developing section for developing an image formed on a photosensitive material by the exposure apparatus. . 14. When N is a positive integer, a step of separating N-bit image data into a plurality of bit groups, and a step of converting the image data of each bit group into analog data by individual conversion means. A step of modulating a light beam supplied from a light beam supply unit to each of the modulation units based on individual analog data, and supplying the modulated light beam to a photosensitive material.