JPH1184293A - Scanning optical system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a scanning optical system capable of preventing dust from adhering to an optical system. SOLUTION: In the case of performing scanning exposure, a solenoid 340 is energized after the blast of pressurized air is started through a filter 306 by a fan 308 inward a partition 312, so that a shutter 304 becomes in an open condition shown by a solid line; therefore, the dust is prevented from entering inside the partition 312 through an aperture part 314, and the dust is prevented from adhering to a polygonal mirror 218, an fθ lens 220, a cylindrical lens 221, a planar mirror 222, a reflection mirror 223 disposed inside the partition 312.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning optical system, and more particularly to a scanning optical system for forming a latent image by scanning and exposing a photosensitive material with a laser beam.

[0002]

2. Description of the Related Art In recent years, for writing an image in a digital lab system or the like that records an image recorded on a photographic film on a photographic paper, an image exposure apparatus that scans and exposes the photographic paper using a light source that generates a laser beam is known. Widely used.

In such an image exposure apparatus, R (red),
A light source that generates a laser beam of each color of G (green) and B (blue) is provided. Based on color image data, R, G,
B. The laser beam is modulated for each color, the laser beam is deflected in the main scanning direction by a deflector such as a polygon mirror, and the photographic paper is conveyed in the sub-scanning direction. The fθ lens, cylindrical lens, plane mirror, folding mirror, etc. The photographic paper was scanned and exposed through the optical system composed of the above to record a color image.

In the scanning optical system of such an image exposure apparatus, as shown in FIG. 16, dust 320 adheres to the fθ lens 220, the folding mirror 223, etc., which are arranged downstream of the optical path of the laser beam from the deflector. If this dust 3
When the laser beam 322 is blocked by the laser light 20, the amount of light is reduced only in that region, and there is a problem that a vertical streak 326 extending in the sub-scanning direction is generated on the printing paper 224.

To solve this problem, a scanning optical system of a conventional image exposure apparatus includes a polygon mirror 218, an fθ lens 220, a cylindrical lens 221, a plane mirror 222, and a polygon mirror 218 as shown in FIG. By disposing the optical system including the folding mirror 223 at the emission position of the laser beam 322 and inside the sealed scanning system optical unit box 334 having the window glass 330 that transmits the laser beam, each component constituting the optical system is provided. As shown in FIG. 17 (B), a device for preventing dust from adhering to the element, as shown in FIG. 17 (A), with respect to the surface of the window glass 330 facing the outside of the scanning optical unit box 334. There was a device further provided with a fan 332 for blowing air.

[0006]

However, in the case shown in FIG. 17A, the scanning system optical unit box 3 is not shown.
Although it is possible to prevent dust from being applied to each element disposed inside the optical system unit 34, dust cannot be applied to the outer surface of the scanning optical unit box 334. As a result, dust adheres to the outer surface of the window glass 330. was there.

On the other hand, in the apparatus shown in FIG. 17B, dust on the outer surface of the window glass 330 can be prevented to some extent by the action of the fan 332, but dust containing moisture adheres to the window glass 330. For example, there is a problem that dust adhered to the window glass 330 with a strong adhesive force cannot be removed.

When dust adheres to the window glass 330 in this manner, the laser beam is blocked by the dust, so that the amount of light is reduced only in that area, and the image recorded on the photographic paper 224 extends in the sub-scanning direction. Vertical streaks occur.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a scanning optical system capable of preventing dust from adhering to an optical system.

[0010]

In order to achieve the above object, a scanning optical system according to the present invention comprises a deflecting means for deflecting a laser beam emitted from a light source in a predetermined scanning direction, and a deflecting means for deflecting the laser beam in a predetermined scanning direction. A scanning system optical unit box in which an optical system for converging the obtained laser beam on the photosensitive material is provided, and the scanning system optical unit box by blowing pressurized air into the scanning system optical unit box And an opening / closing means that is openably and closably disposed at the laser beam emission position of the scanning system optical unit box.

According to the first aspect of the present invention, a deflecting unit for deflecting a laser beam emitted from a light source in a predetermined scanning direction, and an optical system for converging the laser beam deflected by the deflecting unit on a photosensitive material. The opening and closing means arranged so as to be openable and closable at the laser beam emission position of the scanning system optical unit box in which the system is disposed is normally in a closed state, that is, in a state where the scanning system optical unit box is sealed, Only when scanning exposure is performed, the opening / closing means is opened in a state in which pressurizing air is blown into the inside of the scanning system optical unit box by the pressing means to pressurize the inside of the scanning system optical unit box, that is, the laser beam is emitted. By making the scanning system optical unit box be capable of being ejected to the outside, dust can be prevented from entering the inside of the scanning system optical unit box. Incidentally, a polygon mirror, a galvanometer mirror or the like can be applied as the deflecting means.

As described above, according to the scanning optical system of the first aspect, when the scanning exposure is performed at the laser beam emission position of the scanning system optical unit box in which the deflecting means and the optical system are disposed, the scanning optical system is opened. The opening and closing means is provided, so that when the scanning exposure is performed, the opening and closing means is opened while the inside of the scanning optical unit box is pressurized, so that dust inside the scanning optical unit box can be removed. Intrusion can be prevented, and adhesion of dust to the optical system can be prevented.

The scanning optical system according to a second aspect of the present invention is the scanning optical system according to the first aspect, wherein when the scanning exposure is performed using the deflecting unit and the optical system, the scanning system is controlled by the pressing unit. Control means is further provided for sending pressurized air to the inside of the optical unit box and controlling the opening / closing means to be in an open state when the inside of the scanning system optical unit box is pressurized.

As described above, according to the scanning optical system of the second aspect, when scanning exposure is performed using the deflecting means and the optical system, the control means presses the scanning optical system into the scanning optical unit box. Since the pressurizing air is blown and the opening / closing means is controlled to be in an open state, the pressing means and the opening / closing means at the time of scanning exposure can be automatically controlled.

According to a third aspect of the present invention, in the scanning optical system according to the first or second aspect, dust contained in pressurized air blown into the inside of the scanning system optical unit box is captured. And a collecting filter.

As described above, according to the scanning optical system of the third aspect, dust contained in the pressurized air sent to the scanning optical unit box can be collected by the filter. It is possible to prevent dust from entering the inside of the scanning system optical unit box. In this case, the filter can be provided between the pressurizing means and the scanning optical unit box.

In the scanning optical system according to the present invention, the radius of the laser beam on the optical element constituting the optical system is ω, and the gradation of the photosensitive material is γ.
It is preferable that the opening width L in the short side direction of the hole of the filter is determined by the following equation.

[0018]

(Equation 2)

The equation (1) is derived as follows. That is, the relative positional relationship between the dust 320 and the laser beam 322 on the dust adhesion surface changes as time passes from top to bottom in FIG.

The laser beam on the surface of an optical element in which dust adheres to a problem, for example, the element closest to the photosensitive material among the elements constituting the optical system, is converted into an ideal Gaussian beam.
Assuming that the shape of the dust is spherical and the transmittance of the dust laser beam is zero, the diameter of the laser beam on the surface of the element closest to the photosensitive material is 1 / e ² of the maximum intensity of the laser beam (where e is The beam diameter (radius) of the portion having twice the intensity (which is the base of the natural logarithm), that is, the diameter of the Gaussian beam is ω, the radius of the attached dust is d, the light amount when there is no dust is E ₀ , and the dust is blocked. Assuming that the light amount is E ₁ and the radius of the area that is assumed to be blocked by dust is s, the light amounts E ₀ and E
₁ is represented by equations (2) and (3), respectively, and the relative amount of decrease in light amount is represented by equation (4).

[0021]

(Equation 3)

[0022]

(Equation 4)

[0023]

(Equation 5)

Note that s ² in the equations (2) and (3)
And dS are defined by the following definition formula.

S ² = x ² + y ² , dS = dxdy In this definition expression, x and y represent the x coordinate in the main scanning direction and the y coordinate in the sub scanning direction, respectively, with the center of the dust as the origin.

The density change ΔD at this time is expressed by the following equation (5), where γ is the gradation of the photosensitive material.

[0027]

(Equation 6)

By calculating the above equations (2) and (3), ω
When plotted as a function of / d, as shown in FIG. 14, the relative amount of decrease in light quantity decreases as d / ω (radius of dust / beam diameter) increases regardless of the wavelength of the laser beam and each element. Further, by fitting each plot point shown in FIG. 14 by the least square method,

[0029]

(Equation 7)

## EQU1 ## Substituting this into equation (5) gives

[0031]

(Equation 8)

,

[0033]

(Equation 9)

## EQU1 ## When the concentration decrease becomes 0.002 or more, it becomes visible to the human eye.

[0035]

(Equation 10)

Is represented as Therefore, in order to collect such dust using a mesh filter having a large number of rectangular holes, the opening width L in the short side direction of the holes of the rectangular filter is:

[0037]

[Equation 11]

It suffices to satisfy the following. FIG. 15 shows an example of a decrease in the light amount of the R laser beam on the exposure surface due to the attachment of dust of various radii when the beam diameter ω of the laser beam is 408 μm and the wavelength λ of the laser beam is 685 nm.
(A), when the beam diameter ω of the laser beam is 408 μm, the wavelength λ of the laser beam is 685 nm, and the gradation γ of the photosensitive material is 2.55, the density of cyan on the exposed surface due to the adhesion of dust of various radii. An example of the decrease is shown in FIG.

As shown in FIGS. 15A and 15B, the amount of light and the density on the photosensitive surface of the photosensitive material both decrease as the radius d of the dust increases.

It is preferable that the deflecting means in the scanning optical system according to any one of claims 1 to 4 be hermetically closed. In this way, the deflecting means is hermetically sealed, so that when the deflecting means is rotated in a normal environment, the deflecting means is deflected at a rotational speed (for example, 10,000 revolutions / minute or more) that causes the deflecting surface to become cloudy. When rotating the means, contamination on the deflection surface can be prevented.

[0041]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment in which a scanning optical system of the present invention is applied to a digital laboratory system will be described in detail with reference to the drawings. Hereinafter, the digital laboratory system according to the present embodiment will be described first.

(Schematic Configuration of Entire System) FIG. 1 shows a schematic configuration of a digital laboratory system 10 according to the present embodiment, and FIG. 2 shows an appearance of the digital laboratory system 10. As shown in FIG. 1, the lab system 10 includes a line CCD scanner 14, an image processing unit 1
6, a laser printer unit 18 and a processor unit 20. The line CCD scanner 14 and the image processing unit 16 are provided in the input unit 26 shown in FIG. Reference numeral 20 is provided in the output unit 28 shown in FIG.

The line CCD scanner 14 is for reading a film image recorded on a photographic film such as a negative film or a reversal film. For example, a 135 size photographic film, a 110 size photographic film, and a transparent magnetic film are used. Photographic film (2
40 size photographic film: so-called APS film), 1
Film images of photographic films of sizes 20 and 220 (Broni size) can be read. The line CCD scanner 14 reads the film image to be read by the line CCD and outputs image data. Instead of the line CCD scanner 14, an area CCD scanner for reading a film image by an area CCD may be provided.

The image processing section 16 stores image data (scanned image data) output from the line CCD scanner 14.
Is input, and image data obtained by photographing with a digital camera, image data obtained by reading a document other than a film image (for example, a reflection document, etc.) with a scanner, image data generated by a computer, etc. Hereinafter, these are collectively referred to as file image data.) It is also possible to externally input (for example, input via a storage medium such as a memory card, or input from another information processing device via a communication line). It is configured as follows.

The image processing section 16 performs image processing such as various corrections on the input image data, and outputs the image data to the laser printer section 18 as recording image data. Also,
The image processing unit 16 outputs image data on which image processing has been performed to an external device as an image file (for example, outputs the image data to a storage medium such as a memory card, or transmits the image data to another information processing device via a communication line). Is also possible.

The laser printer section 18 has a laser light source for oscillating R, G, and B laser beams, and irradiates a photographic paper with a laser beam modulated in accordance with recording image data input from the image processing section 16. Then, an image is recorded on photographic paper by scanning exposure. Further, the processor unit 20 includes:
The photographic paper on which an image has been recorded by scanning exposure by the laser printer unit 18 is subjected to color development, bleach-fixing, washing, and drying. Thus, an image is formed on the printing paper.

(Configuration of Line CCD Scanner) Next, the configuration of the line CCD scanner 14 will be described. FIG. 3 shows a schematic configuration of an optical system of the line CCD scanner 14. The optical system includes a halogen lamp, a metal halide lamp, or the like, and includes a light source 30 that irradiates light to the photographic film 22. A diffusion box 36 is provided.

The photographic film 22 includes a light diffusion box 36.
Are transported in a direction orthogonal to the optical axis by a film carrier 38 (see FIG. 5 and not shown in FIG. 3) disposed on the light exit side of the optical disc. In FIG. 3, the long photographic film 22 is used.
The slide film (reversal film) or the AP held in the slide holder for each frame
For the S film, a dedicated film carrier is prepared for each (the film carrier for the APS film has a magnetic head for reading information magnetically recorded on the magnetic layer), and these photographic films are transported. Is also possible.

Between the light source 30 and the light diffusion box 36, C (cyan), M (magenta), and Y (yellow) dimming filters 114C, 114M, and 114Y extend along the optical axis of the emitted light. A lens unit 4 that is provided in order and forms an image of light transmitted through the film image along an optical axis on a side opposite to the light source 30 across the photographic film 22.
0 and a line CCD 116 are sequentially arranged. Although FIG. 3 shows only a single lens as the lens unit 40, the lens unit 40 is actually a zoom lens composed of a plurality of lenses.

The line CCD 116 is provided with three sensing units in which a large number of photoelectric conversion elements composed of CCD cells are arranged in a line and an electronic shutter mechanism is provided in parallel with each other at intervals. Any one of R, G, and B color separation filters is attached to the light incident side (a so-called three-line color CC).
D). The line CCD 116 is arranged so that the light receiving surface of each sensing unit matches the image forming position of the lens unit 40. In addition, in the vicinity of each sensing unit, a transfer unit is provided corresponding to each sensing unit, and charges accumulated in each CCD cell of each sensing unit are sequentially transferred through the corresponding transfer unit. You. Although not shown, a shutter is provided between the line CCD 116 and the lens unit 40.

FIG. 4 shows a schematic configuration of an electric system of the line CCD scanner 14. Line CCD scanner 1
4 includes a microprocessor 46 for controlling the entire line CCD scanner 14. The microprocessor 46 has a RAM 64 (for example, SRA
M), ROM 66 (for example, RO whose storage contents can be rewritten)
M), and a motor driver 48 is connected, and a filter driving motor 54 is connected to the motor driver 48. The filter drive motor 54 can slide the dimming filters 114C, 114M and 114Y independently of each other.

The microprocessor 46 turns on and off the light source 30 in conjunction with turning on and off a power switch (not shown). The microprocessor 46 includes a line CCD 1
When the film image is read (photometric) by the filter drive motor 54, the dimming filter 11 is
4C, 114M, and 114Y are independently slid, and the amount of light incident on the line CCD 116 is adjusted for each component color light.

The motor driver 48 moves the zoom drive motor 70 that changes the zoom magnification of the lens unit 40 by relatively moving the positions of the plurality of lenses of the lens unit 40, and moves the entire lens unit 40. And a lens drive motor 106 for moving the image forming position of the lens unit 40 along the optical axis is connected.
The microprocessor 46 controls the zoom drive motor 7 according to the size of the film image, whether or not to perform trimming, and the like.
By 0, the zoom magnification of the lens unit 40 is changed to a desired magnification.

On the other hand, a timing generator 74 is connected to the line CCD 116. The timing generator 74 generates various timing signals (clock signals) for operating the line CCD 116, an A / D converter 82 described later, and the like. The signal output terminal of the line CCD 116 is connected to an A / D converter 82 via an amplifier 76. The signal output from the line CCD 116 is amplified by the amplifier 76 and converted to digital data by the A / D converter 82. Is done.

The output terminal of the A / D converter 82 is connected to an interface (I / F) circuit 90 via a correlated double sampling circuit (CDS) 88. The CDS 88 samples the feedthrough data indicating the level of the feedthrough signal and the pixel data indicating the level of the pixel signal, and subtracts the feedthrough data from the pixel data for each pixel. Then, the calculation result (pixel data accurately corresponding to the amount of charge stored in each CCD cell) is expressed by I /
The data is sequentially output to the image processing unit 16 as scan image data via the F circuit 90.

It should be noted that R, G,
Since the photometric signals of B are output in parallel, the amplifier 76, A
Three signal processing systems including a / D converter 82 and a CDS 88 are also provided, and the I / F circuit 90 outputs R, G, and B image data as scan image data in parallel.

The motor driver 48 has a line C
A shutter drive motor 92 for opening and closing a shutter provided between the CD 16 and the lens unit 40 is connected. The dark output of the line CCD 116 is corrected by the image processing unit 16 at the subsequent stage. The dark output level can be obtained by closing the shutter by the microprocessor 46 when the film image is not being read. .

(Configuration of Image Processing Unit) Next, the image processing unit 16
Will be described with reference to FIG. Image processing unit 1
Reference numeral 6 is provided with a line scanner correction unit 122 corresponding to the line CCD scanner 14. The line scanner correction unit 122 includes a dark correction circuit 124, a defective pixel correction unit 128, and a light correction circuit 13 corresponding to R, G, and B image data output in parallel from the line CCD scanner 14.
There are provided three signal processing systems composed of 0s.

The dark correction circuit 124 includes a line CCD 116
In the state where the light incident side is shielded from light by a shutter provided between the line CCD 16 and the lens unit 40, data input from the line CCD scanner 14 (representing the dark output level of each cell of the sensing unit of the line CCD 116). Data) is stored for each cell, and correction is performed by subtracting the dark output level of the cell corresponding to each pixel from the scan image data input from the line CCD scanner 14.

In addition, the photoelectric conversion characteristics of the line CCD 116 have variations in density for each cell. The light correction circuit 130 at the subsequent stage of the defective pixel correction unit 128 reads the adjustment film image with the line CCD 116 while the adjustment film image having a constant density is set on the entire screen of the line CCD scanner 14. By line C
A gain is set for each cell based on the image data of the adjustment film image input from the CD scanner 14 (the density variation of each pixel represented by this image data is caused by the variation of the photoelectric conversion characteristics of each cell). In advance, the image data of the film image to be read input from the line CCD scanner 14 is corrected for each pixel according to the gain determined for each cell.

On the other hand, if the density of a specific pixel is greatly different from the density of other pixels in the image data of the film image for adjustment, the cell corresponding to the specific pixel in the line CCD 116 has some abnormalities. The specific pixel can be determined as a defective pixel. Defective pixel correction unit 12
8 stores the address of the defective pixel based on the image data of the film image for adjustment,
Among the image data of the film image to be read inputted from 4, the data of the defective pixel is interpolated from the data of the surrounding pixels to newly generate data.

In the line CCD 116, three lines (CCD cell rows) extending in a direction perpendicular to the direction in which the photographic film 22 is transported are arranged at predetermined intervals along the direction in which the photographic film 22 is transported. Therefore, there is a time difference between the timings at which the output of the image data of the R, G, and B component colors from the line CCD scanner 14 is started.
The line scanner correction unit 122 is provided with a delay circuit (not shown).
The output timing of the image data is delayed with a different delay time for each of the remaining two colors based on the output timing of the image data that is output latest, so that the G and B image data are output simultaneously.

The output terminal of the line scanner correction unit 122 is connected to the input terminal of the selector 132.
Are output to the selector 132. The input terminal of the selector 132 is also connected to the data output terminal of the input / output controller 134. From the input / output controller 134, externally input file image data is input to the selector 132. Selector 1
The output terminals of the 32 are connected to the input / output controller 134 and the data input terminals of the image processor units 136A and 136B, respectively. The selector 132 can selectively output the input image data to each of the input / output controller 134 and the image processors 136A and 136B.

The image processor section 136A includes a memory controller 138, an image processor 140, and three frame memories 142A, 142B, 142C. Frame memories 142A, 142B, 142C
Has a capacity capable of storing image data of a film image for one frame, and the image data input from the selector 132 is stored in any of the three frame memories 142. The memory controller 138 The data of each pixel of the input image data is stored in the frame memory 14.
2 so that they are stored in a certain order in the storage area,
The address at which the image data is stored in the frame memory 142 is controlled.

The image processor 140 takes in the image data stored in the frame memory 142, performs gradation conversion, color conversion, hypertone processing for compressing the gradation of an ultra-low frequency luminance component of the image, and sharpness while suppressing graininess. Various image processing such as hyper sharpness processing for emphasizing is performed. Note that the processing conditions of the above image processing are automatically calculated by an auto setup engine 144 (described later), and the image processing is performed according to the calculated processing conditions. The image processor 140 is connected to the input / output controller 134, and the image data subjected to the image processing is temporarily stored in the frame memory 142 and then output to the input / output controller 134 at a predetermined timing. Note that the image processor unit 136B has the same configuration as the above-described image processor unit 136A, and a description thereof will be omitted.

In the present embodiment, each line image is read twice by the line CCD scanner 14 at different resolutions. In the first reading at a relatively low resolution (hereinafter referred to as pre-scan), even when the density of the film image is extremely low (for example, a negative image overexposed on a negative film), a line CCD is used.
The reading of the film image is performed under the reading conditions (light amounts of the light irradiating the photographic film in each of the R, G, and B wavelength ranges, and the charge storage time of the CCD) determined so as not to cause the saturation of the stored charge in 116. . The image data (pre-scan image data) obtained by the pre-scan is input from the selector 132 to the input / output controller 134, and further output to the auto setup engine 144 connected to the input / output controller 134.

The auto setup engine 144 has a C
PU 146, RAM 148 (for example, DRAM), ROM
150 (for example, a rewritable ROM) and an input / output port 152, which are connected to each other via a bus 154.

The auto set-up engine 144 reads the image at a second relatively high resolution by the line CCD scanner 14 based on the pre-scanned image data of the film image for a plurality of frames input from the input / output controller 134 (hereinafter, referred to as “high-resolution”). In addition to determining the light amount of the light source 30 in the fine scan, the image processor 1 calculates image processing conditions for the image data obtained by the fine scan, and calculates the calculated processing conditions.
36 to the image processor 140. In the calculation of the processing conditions of this image processing, it is determined whether or not there are a plurality of film images that photograph a similar scene based on the exposure amount at the time of photographing, the photographing light source type and other characteristic amounts, and a plurality of film images that photograph the similar scene are determined. Are determined, the image processing conditions for the fine scan image data of these film images are the same or similar.

The optimum processing conditions for image processing vary depending on whether the image data after image processing is used for recording an image on photographic paper in the laser printer unit 18 or output to the outside. Since the image processing unit 16 is provided with two image processor units 136A and 136B, for example, when the image data is used for recording an image on photographic paper and is output to the outside, the auto setup engine 144 is used. Calculates the optimal processing conditions for each application, and calculates the image processor units 136A and 136A.
Output to B. Thereby, the image processor unit 13
6A and 136B, the same fine scan image data is subjected to image processing under different processing conditions.

Further, the auto setup engine 144
Calculates an image recording parameter that defines a gray balance or the like when an image is recorded on photographic paper by the laser printer unit 18 based on the pre-scan image data of the film image input from the input / output controller 134, The image data is output simultaneously when the image data for recording (described later) is output to the printer unit 18. Further, the auto setup engine 144 calculates the processing conditions of the image processing for the file image data input from the outside in the same manner as described above.

The input / output controller 134 is the I / F circuit 1
It is connected to the laser printer section 18 via 56.
When the image data after image processing is used for recording an image on photographic paper, the image data processed by the image processor 136 is transferred from the input / output controller 134 via the I / F circuit 156 to the recording image. The data is output to the laser printer unit 18 as data. The auto setup engine 144 is connected to a personal computer 158. When the image data after the image processing is output to the outside as an image file, the image data processed by the image processor unit 136 is sent from the input / output controller 134 to the auto setup engine 144.
Is output to the personal computer 158 via the.

The personal computer 158 has a CPU
160, memory 162, display 164 and keyboard 166 (see also FIG. 2), hard disk 168, C
It includes a D-ROM driver 170, a transport control unit 172, an expansion slot 174, and an image compression / decompression unit 176.
These are connected to each other via a bus 178. The transport controller 172 is connected to the film carrier 38 and controls the transport of the photographic film 22 by the film carrier 38. In addition, the film carrier 38
When the APS film is set in the APS film, information (for example, image recording size) read from the magnetic layer of the APS film by the film carrier 38 is input.

A driver (not shown) for reading / writing data from / to a storage medium such as a memory card.
A communication control device for communicating with another information processing device is connected to the personal computer 158 via the expansion slot 174. When image data for output to the outside is input from the input / output controller 134, the image data is output to the outside (the driver, the communication control device, or the like) as an image file via the expansion slot 174. When file image data is input from outside via the expansion slot 174, the input file image data
4 to the input / output controller 134. In this case, the input / output controller 134 outputs the input file image data to the selector 132.

The image processing section 16 outputs prescanned image data and the like to the personal computer 158,
The film image read by the line CCD scanner 14 is displayed on the display 164, or the image obtained by recording on the photographic paper is estimated and displayed on the display 164, and the operator can correct the image via the keyboard 166. When instructed, this can be reflected in the processing conditions of image processing.

(Structures of Laser Printer Unit and Processor Unit) Next, the structures of the laser printer unit 18 and the processor unit 20 will be described. FIG. 6 shows a laser printer unit 1.
The configuration of the optical system No. 8 is shown. Laser printer unit 1
8 are laser light sources 210R, 210G, 2
It has three laser light sources of 10B. Laser light source 2
Reference numeral 10R denotes a semiconductor laser (LD) that emits a laser beam having an R wavelength (for example, 680 nm) (hereinafter, referred to as an R laser beam). In addition, laser light source 2
The 10G includes an LD and a wavelength conversion element (SHG) that converts a laser beam emitted from the LD into a laser beam having a half wavelength, and a laser having a wavelength from SHG to G (for example, 532 nm). The oscillation wavelength of the LD is determined so that a beam (hereinafter, referred to as a G laser beam) is emitted. Similarly, the laser light source 210B is also an LD
And the SHG, and the oscillation wavelength of the LD is determined so that the SHG emits a laser beam of a B wavelength (for example, 475 nm) (hereinafter, referred to as a B laser beam). Note that a solid-state laser may be used instead of the LD.

Laser light sources 210R, 210G, 210B
Each of the collimator lenses 21
2. An acousto-optic modulator (AOM) 214 is arranged in order. The AOM 214 is arranged so that each of the incident laser beams passes through the acousto-optic medium, and is connected to the AOM driver 213 (see FIG. 9). When the high frequency signal is input from the AOM driver 213, the AOM 214 is connected to the AOM 214. An ultrasonic wave according to the high-frequency signal propagates in the acousto-optic medium, and an acousto-optic effect acts on a laser beam transmitted through the acousto-optic medium, causing diffraction, and a laser beam having an intensity corresponding to the amplitude of the high-frequency signal. Are emitted from the AOM 214 as diffracted light.

On the diffracted light emission side of the AOM 214,
Window glass 301 and mirror 215 provided corresponding to each of the diffracted lights of R, G, and B emitted from AOM 214
R, 215G, and 215B are arranged, and a spherical lens 216, a cylindrical lens 217, and a polygon mirror 218 as a deflecting unit are sequentially arranged on each laser beam emission side of each of the mirrors 215R, 215G, and 215B. The R laser beam, the G laser beam, and the B laser beam emitted as diffracted light from each of the AOMs 214 pass through the window glass 301 and are reflected by the mirrors 215R, 215G, and 215B, respectively. Cylindrical lens 217
The light is applied to substantially the same position on the reflection surface of the polygon mirror 218 via the Incidentally, as shown in the broken side view of FIG.
Numeral 18 is sealed by a partition wall 300 (not shown in FIG. 6) provided with a window glass 302 that transmits each laser beam corresponding to a position where each laser beam is incident and a position where each laser beam is emitted.

On the laser beam emission side of the polygon mirror 218, an fθ lens 220, a cylindrical lens 221 for correcting surface tilt having power in the sub-scanning direction, and a plane mirror 222 are arranged in this order.
A folding mirror 223 is disposed on the side of emitting a laser beam.

The mirror 215, the spherical lens 216, the cylindrical lens 217, the polygon mirror 218, the fθ lens 220, the cylindrical lens 221, the plane mirror 222, and the folding mirror 223 are covered by a partition 312 as shown in FIGS. (The upper surface of the partition wall 312 is shown in FIG. 6, and the mirror 215, the spherical lens 216, and the cylindrical lens 217 are not shown in FIG. 7).

The partition 312 is provided with an opening 314 having a position and a size through which the laser beam emitted from the folding mirror 223 can pass, and the upper end of the opening 314 is swung by a hinge 303 in the direction of arrow S1 in FIG. One end of a shutter 304 is movably attached as opening / closing means.

The shutter 304 has substantially the same shape and size as the opening 314 of the partition wall 312, and the other end of the shutter 304 is connected to the shaft 342 of the solenoid 340 via a link 344. I have. When the solenoid 340 is not energized, the shutter 304 in the present embodiment is in the state shown by the broken line in FIG. 7, that is, the shutter 304 is closed, and when the solenoid is energized, the state shown by the solid line in FIG. The shutter 304 is opened. Therefore, at the time of a power failure, the shutter 304 is closed and the opening 31 is closed.
4 can be prevented from entering.

The solenoid 340 is connected to a printer control circuit 238 (to be described later) as control means for controlling each part of the laser printer section 18. The operation of the solenoid 340 is controlled by the printer control circuit 238. Is done.

As shown in FIG. 7, on the upper surface of the partition 312,
An opening 316 (not shown in FIG. 6) is provided.
The lowermost outer peripheral surface of a filter 306 (not shown in FIG. 6) is joined to the inner peripheral surface of the opening 316, and the upper part of the filter 306 is pressed into the partition wall 312 via the filter 306. Fan 3 as pressure means for blowing air
08 (not shown in FIG. 6) is attached. The filter 306 is provided with each of the holes 31 shown in the plan view of FIG.
8 is manufactured as an air filter configured such that the opening width L in the short side direction satisfies the above expression (1), whereby dust having a size larger than the opening width L is collected,
Intrusion into the inside of the partition 312 can be prevented.

The fan 308 is connected to a printer control circuit 238 (to be described later).
The operation of is controlled by the printer control circuit 238.

When the shutter 304 is open, the three laser beams reflected by the polygon mirror 218 are transmitted through the window glass 302, the fθ lens 220, and the cylindrical lens 221 in order, are reflected by the plane mirror 222, and are turned back. The light is reflected in a substantially horizontal direction by the mirror 223 and is irradiated on the photographic paper 224 through the opening 314. The partition 312 corresponds to a scanning optical unit box of the present invention.

FIG. 9 shows a schematic configuration of an electric system of the laser printer section 18 and the processor section 20. The laser printer section 18 has a frame memory 230 for storing image data. The frame memory 230 is connected to the image processing unit 16 via the I / F circuit 232, and the recording image data (R, R, and R for each pixel of the image to be recorded on the photographic paper 224) input from the image processing unit 16 The image data representing the G and B densities are temporarily stored in the frame memory 230 via the I / F circuit 232. Frame memory 230
Are connected to an exposure unit 236 via a D / A converter 234 and to a printer unit control circuit 238.

The exposure section 236 has three laser light sources 210 composed of LDs (and SHGs) as described above, and also has three systems of AOM 214 and AOM driver 213. The polygon mirror 218 and the polygon mirror 21 are provided.
The main scanning unit 240 includes a motor for rotating the shutter 8, a fan 308 for blowing pressurized air into the partition wall 312, a solenoid 340 for opening and closing the shutter 304, and the like. The exposure unit 236 is connected to a printer unit control circuit 238, and the operation of each unit is controlled by the printer unit control circuit 238. A printer unit driver 242 is connected to the printer unit control circuit 238. The printer unit driver 242 includes a fan 244 that blows air to the exposure unit 236, and photographic paper stored in a magazine loaded in the laser printer unit. Is connected to a magazine motor 246 for pulling out from the magazine. The printer control circuit 238 is connected to a back print unit 248 that prints characters and the like on the back surface of the printing paper 224. The operations of the fan 244, the magazine motor 246, and the back print unit 248 are controlled by the printer control circuit 238.

The printer control circuit 238 has a magazine sensor 250 for detecting the attachment / detachment of a magazine in which the unexposed photographic paper 224 is stored and the size of the photographic paper stored in the magazine. Operation panel 252 (see also FIG. 2) for inputting, processor unit 20
The densitometer 254 for measuring the density of the image visualized by processing such as development is connected to the processor unit control circuit 256 of the processor unit 20.

The processor control circuit 256 detects the passage of the photographic paper 224 conveyed along the photographic paper conveyance path in the body of the processor 20, and detects the level of various processing liquids stored in the processing tank. Various sensors 258 for detecting the position and the like
Is connected.

The processor control circuit 256 includes:
A sorter 260 (see FIG. 2) for sorting the photographic paper discharged to the outside of the machine after completion of the processing such as development into a predetermined group, and a replenishing system 26 for replenishing a processing tank with a replenisher.
2. An automatic cleaning system 264 for cleaning rollers and the like is connected, and various pumps / solenoids 268 are connected via a processor driver 266. These sorters 260, replenishment systems 262, automatic cleaning systems 264, and various pumps / solenoids 26
The operation of 8 is controlled by the processor unit control circuit 256.

Next, the operation of the printer control circuit 238 when recording an image on the printing paper 224 will be described with reference to the schematic flowchart of FIG. In addition, FIG.
10 is a schematic flowchart of a control program executed by a CPU (not shown) provided in the printer control circuit 238 when recording an image on the photographic paper 224;
The control program is stored in a memory (not shown) provided in the printer control circuit 238 in advance.

In step 400 of FIG. 10, various corrections are made to the recording image data based on the image recording parameters input from the image processing section 16 to generate scanning exposure image data. To memorize.

In the next step 402, the rotation of the fan 308 is started to blow the pressurized air into the partition 312, and in the next step 404, the solenoid 340 is energized while the inside of the partition 312 is pressurized. The shutter 304 is opened. Even if the shutter 304 is opened in the step 404, since the inside of the partition 312 is pressurized in the step 402,
It is possible to prevent dust from entering the inside of the partition 312 from the opening 314.

In the next step 406, the polygon mirror 218 is rotated in the direction of arrow A in FIG.
In step 8, laser beams are emitted from the laser light sources 210R, 210G, and 210B, and in the next step 410, scanning exposure is performed according to the following procedure.

That is, the scanning exposure image data generated in step 400 is output from the frame memory 230 to the AOM driver 213 via the D / A converter 234. As a result, the scanning exposure image data is converted into an analog signal and input to the AOM driver 213.

The AOM driver 213 changes the amplitude of the ultrasonic signal supplied to the AOM 214 according to the level of each input analog signal, and changes the intensity of the laser beam emitted as diffracted light from the AOM 214 to the analog signal level ( That is, the modulation is performed in accordance with one of the R density, the G density, and the B density of each pixel of the image to be recorded on the photographic paper 224. Therefore, the photographic paper 22 is output from the three AOMs 214.
4 emits R, G, and B laser beams whose intensity is modulated according to the R, G, and B densities of an image to be recorded. These laser beams are mirror 215, spherical lens 216, cylindrical lens 217, and polygon mirror. 218, fθ
Photographic paper 2 via lens 220, cylindrical lens 221, plane mirror 222, and return mirror 223
24.

As the polygon mirror 218 rotates in the direction of arrow A in FIG.
The main scanning is performed by scanning along the arrow B direction, and the sub-scanning of the laser beam is performed by conveying the printing paper 224 at a constant speed along the arrow C direction in FIG.
A latent image is recorded on the printing paper 224 by the scanning exposure.

When the scanning exposure is completed as described above, in the next step 412, the energization to the solenoid 340 is terminated while the inside of the partition wall 312 is being pressurized by the fan 308, so that the shutter 304 is closed. 3
Then, the rotation of the lens 08, the rotation of the polygon mirror 218, and the emission of each laser beam are ended, and the present control program is ended.

The photographic paper 224 on which the latent image has been recorded by the above scanning exposure is sent to the processor section 20, and
Each process of color development, bleach-fix, washing, and drying is performed.
Thus, an image is formed on the printing paper 224.

As described in detail above, the scanning optical system of the laser printer unit 18 according to the present embodiment includes the mirror 21
5 and the mirror 215, an element constituting the optical system located downstream of the optical path of the laser beam is surrounded by a partition 312, and a shutter 304 is provided at a position where the laser beam is emitted from the partition 312. By opening the opening, each laser beam can be emitted to the outside of the partition wall 312, and since the window glass is not provided at the laser beam emission position of the partition wall 312, the problem that dust adheres to the outer surface of the window glass is eliminated. Be able to
When scanning exposure is performed, the shutter 304 is opened in a state where the inside of the partition wall 312 is pressurized by the fan 308, so that dust can be prevented from entering the inside of the partition wall 312 and provided inside the partition wall 312. It is possible to prevent dust from adhering to each element such as a lens and a mirror constituting the optical system.

The scanning optical system of the laser printer unit 18 according to the present embodiment is configured so that the opening width L of the hole 318 of the filter 306 in the short side direction satisfies the expression (1).
Since No.06 is manufactured, it is possible to prevent intrusion of dust into the partition wall 312 due to blowing of the pressurized air of the fan 308, particularly dust having a size capable of generating a vertical streak visible in an image to be formed. .

Further, the scanning optical system of the laser printer section 18 according to the present embodiment includes the polygon mirror 218 and the partition wall 3.
00, the polygon mirror 218 is rotated at a rotation speed (for example, 10,000 rotations / minute or more) at which the mirror surface becomes cloudy when rotated in a normal environment. Can be prevented, and contamination of the mirror surface can be prevented.

In this embodiment, the case where the intensity of the laser beam is modulated by the AOM has been described. However, the present invention is not limited to this. For example, an electro-optic modulator (EOM) may be used instead of the AOM. Alternatively, a mode may be employed in which the intensity of a laser beam is modulated by applying a magneto-optical modulator (MOM).

In the present embodiment, the case where the optical system after the mirror 215 is surrounded by the partition wall 312 has been described.
The present invention is not limited to this, and for example, may be configured to surround all optical systems including the light source 210,
Further, the optical system including only the polygon mirror 218 and thereafter may be surrounded.

Further, in this embodiment, the shutter 304
Is attached to the partition 312 by the hinge 303, and the opening and closing operation of the shutter 304 is controlled by energizing the solenoid 340. However, the present invention is not limited to this.
Alternatively, the shutter 304 may be moved to a position where the opening 314 is fully opened and a position where the opening 314 is fully closed by using a driving unit such as a motor for moving the shutter 304 in the vertical direction without being attached to the shutter 12.

[Other Embodiments] Next, other embodiments of the present invention will be described. Note that the configuration and operation of parts other than the laser printer unit 18 in this embodiment are the same as those in the above-described embodiment, and a description thereof will be omitted.
In the laser printer unit 18, the same parts as those in the above embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIGS. 11 and 12, the laser printer unit 18 of the present embodiment is different from the laser printer unit of the above-described embodiment shown in FIGS.
5R, 215G, and 215B are one plane mirror 215, the plane mirror 222 is a cylindrical mirror 222A, and the folding mirror 223.
Laser beam emission method is not in the horizontal direction,
The difference is that the direction is substantially vertically downward.

Therefore, the opening 31 in the above-described embodiment is used.
An opening 314A corresponding to No. 4 is provided on the lower surface of the partition wall 312 and at a position where each laser beam emitted from the folding mirror 223 can pass therethrough.
12A, one end of a shutter 310 is attached by a hinge 309 so as to swing in the direction of arrow S2 in FIG. 12, and the other end of the shutter 310 is connected to the shaft of 342.

Therefore, in this embodiment, the printing paper 2
Numeral 24 denotes a scanning exposure surface which is positioned so as to correspond to the emission direction of the laser beam from the return mirror 223, and the irradiation position of each laser beam is changed by the rotation of the polygon mirror 218 in the direction of arrow A in FIG. The main scanning is performed by scanning along the direction.
The laser beam is sub-scanned by being conveyed at a constant speed along the direction of the arrow C, and an image is recorded on the printing paper 224 by scanning exposure.

Note that the folding mirror 223 may be omitted, and the photographic paper 224 may be reflected directly by the cylindrical mirror 222A in a substantially vertically downward direction.

The same effect as in the above embodiment can also be obtained in the laser printer unit 18 having such a configuration.

[0112]

According to the scanning optical system of the present invention, the scanning optical system is opened when scanning exposure is performed at the laser beam emission position of the scanning system optical unit box in which the deflecting means and the optical system are disposed. Since the opening / closing means is set in a state, the scanning means is opened while the inside of the scanning system optical unit box is pressurized when scanning exposure is performed. This prevents the intrusion of dust and prevents the dust from adhering to the optical system.

Further, according to the scanning optical system of the third and fourth aspects, dust contained in the pressurized air sent to the scanning optical unit box can be collected by the filter. The effect is obtained that dust can sometimes be prevented from entering the inside of the scanning optical unit box.

Further, according to the scanning optical system of the present invention, since the deflecting means is sealed, when the deflecting means is rotated in a normal environment, the deflecting surface of the deflecting means may be fogged. When the deflecting unit is rotated at a rotation speed (for example, 10,000 rotations / minute or more), an effect is obtained that contamination on the deflecting surface can be prevented.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of a digital laboratory system according to an embodiment.

FIG. 2 is an external view of a digital laboratory system.

FIG. 3 is a schematic configuration diagram of an optical system of the line CCD scanner.

FIG. 4 is a block diagram showing a schematic configuration of an electric system of the line CCD scanner.

FIG. 5 is a block diagram illustrating a schematic configuration of an image processing unit.

FIG. 6 is a schematic configuration diagram of an optical system of a laser printer unit.

FIG. 7 is a schematic cutaway side view of the optical system of the laser printer unit.

FIG. 8 is a schematic plan view illustrating an opening width in a short side direction of a hole of a filter.

FIG. 9 is a block diagram illustrating a schematic configuration of an electric system of a laser printer unit and a processor unit.

FIG. 10 is a schematic flowchart of a control program executed by a printer control circuit during scanning exposure.

FIG. 11 is a schematic configuration diagram of an optical system of a laser printer unit according to another embodiment.

FIG. 12 is a schematic cutaway side view of an optical system of a laser printer unit according to another embodiment.

FIG. 13 is a schematic diagram showing a change in a relative positional relationship between dust and a laser beam with time on a dust adhesion surface.

FIG. 14 is a graph showing an example of a change in a relative amount of decrease in light amount with a change in a radius of a dust / a beam diameter.

FIG. 15A is a graph showing an example of a decrease in the amount of R laser beam on the exposure surface at various radii of the adhered dust, and FIG. 15B is a graph showing cyan light on the exposure surface at various radii of the adhered dust. It is a graph which shows an example of a density fall.

FIG. 16 is a schematic diagram showing generation of vertical streaks caused by adhesion of dust to a lens, a mirror, and the like.

FIG. 17 is a cutaway side view showing an example of a conventional image exposure apparatus for preventing dust from adhering to a lens, a mirror, and the like;
The optical system after the polygon mirror is sealed in the scanning optical unit box, and (B) is provided with a fan corresponding to (A) the window glass provided in the scanning optical unit box. is there.

[Explanation of symbols]

 Reference Signs List 18 laser printer unit 210R, 210G, 210B laser light source (light source) 214 acousto-optic modulator 218 polygon mirror (deflecting unit) 220 fθ lens 221 cylindrical lens 222 plane mirror 223 folding mirror 238 printer unit control circuit (control unit) 304, 310 Shutter (opening / closing means) 306 Filter 308 Fan (pressurizing means) 312 Partition wall (scanning optical unit box)

Claims (5)

[Claims] A scanning means for deflecting a laser beam emitted from a light source in a predetermined scanning direction, and an optical system for converging the laser beam deflected by the deflection means on a photosensitive material. System optical unit box; pressurizing means for blowing pressurized air into the scanning system optical unit box to pressurize the inside of the scanning system optical unit box; and emitting the laser beam from the scanning system optical unit box. A scanning optical system comprising: an opening / closing means arranged to be openable / closable at a position. 2. When performing scanning exposure using said deflecting means and said optical system, said pressurizing means blows pressurized air into said scanning system optical unit box and said scanning system optical unit box. 2. The scanning optical system according to claim 1, further comprising control means for controlling the opening / closing means to be in an open state in a state where the inside is pressurized. 3. The scanning optical system according to claim 1, further comprising a filter for collecting dust contained in pressurized air sent into the inside of the scanning system optical unit box. 4. When the radius of the laser beam on the optical element constituting the optical system is ω and the gradation of the photosensitive material is γ, the opening width L of the filter hole in the short side direction is represented by the following formula: 4. The scanning optical system according to claim 3, wherein: (Equation 1) 5. The deflecting means is hermetically sealed.
The scanning optical system according to claim 1.