JP2003089240A - Image recording method and image recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image recording method and an image recorder employing a light source of two dimensional arrangement, e.g. combination of a light source and a DMD, in which an image can be recorded with an arbitrary resolution. SOLUTION: At the time of recording an image formed by a light source of two dimensional arrangement having a light source group of two dimensional arrangement, the image recording position on a recording medium by the light source group is shifted in the direction including at least one component of the two dimensional arranging direction of the light source group during recording operation depending on the altered magnification of resolution per recording pixel of a set light source group. In correspondence with the shift, each pixel of light source group is modulated depending on a recording image and then the image is recorded on the recording medium.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technical field of image recording using a two-dimensional array light source such as a combination of a two-dimensional spatial modulation element and a light source, and more specifically, to image recording using a two-dimensional array light source. In addition, the present invention relates to an image recording method and an image recording apparatus capable of changing the resolution without using a zoom lens or a plurality of imaging optical systems.

[0002]

2. Description of the Related Art In digital image exposure used in various printers, a laser beam is deflected in a main scanning direction, and a recording medium and an optical system are relatively moved in a sub scanning direction orthogonal to the main scanning direction. The mainstream is so-called laser beam scanning exposure (raster scan), in which the recording medium is two-dimensionally exposed by a laser beam modulated according to a recorded image by moving the laser beam.

On the other hand, in recent years, a two-dimensional pixel array such as a liquid crystal display (hereinafter, referred to as LCD), a digital micromirror device (hereinafter, referred to as DMD), which has been used as a display means in a display, a monitor or the like. Various digital image recording apparatuses using a spatial (light) modulation element having a have been proposed. In this image recording apparatus, basically, an image formed by a spatial modulation element is projected / formed on a recording medium to expose the recording medium,
Record the image.

FIG. 20 shows an outline of image recording disclosed in US Pat. No. 5,049,901 and European Patent No. 0992350A1 as an example of image recording using DMD. As is well known, the DMD 100 is configured by arranging a large number of mirrors 102, and the light emitted from a light source (not shown) and reflected by the on (image recording state) mirror 102 is an imaging optical system. An image is recorded by forming an image on the recording medium Pt by 104.

In the example shown in FIG. 20, the recording medium P
t is conveyed in the scanning direction (the arrow direction in the figure) that matches the one pixel array direction of the DMD 106 (the arrangement direction of the mirrors 102a to 102c in the figure). In FIG. 20A, the mirror 102a of the DMD 100 is on and the other mirrors 102 are off, and only the light reflected by the mirror 102a forms an image on the recording medium Pt, and this position (black coating) The image is recorded at (position).

The recording medium Pt is conveyed to the mirror 102a.
When the position where the image is recorded is moved by, the mirror 102a is correspondingly moved as shown in FIG.
Is turned off, only the mirror 102b is turned on, an image is recorded at the same position on the recording medium Pt, and when the recording medium Pt is further conveyed, the mirror 102b is turned off and only the mirror 102c is turned on. Then, the image is recorded at the same position. That is, in this image recording method, the image display by the DMD 100 is switched according to the conveyance of the recording medium Pt, and the image displayed on the DMD 100 is moved (shifted) in the scanning direction, so that the image is recorded on the conveyed recording medium Pt. To follow / stop the mirrors 102
Two-dimensional image recording is performed by multiple exposure by.

[0007]

By the way, an optical system including such a light source and a spatial modulation element, or a light source arranged two-dimensionally (hereinafter, these are referred to as a two-dimensional array light source).
In an image recording apparatus that forms an image on the recording medium and projects / images the image on a recording medium, the resolution of the image to be recorded depends on the resolution (pixel pitch) of the two-dimensional array light source and the magnification of the imaging optical system. Will be decided. Therefore, there are a plurality of resolutions, for example, 2540 dpi and 2438 dpi.
And 2400 dpi, in order to perform image recording corresponding to a plurality of resolutions that are not in a multiple relationship with each other, it is necessary to prepare a zoom lens and a number of imaging lenses according to the resolution to be recorded. The configuration is complicated, and it is disadvantageous in terms of cost and space.

An object of the present invention is to solve the above problems of the prior art. An optical system in which a light source and a two-dimensional spatial modulation element such as a DMD are combined, and a two-dimensionally arranged point light source is used. In image recording using a two-dimensional array light source, such as an optical system for forming an image by using a two-dimensional array light source, it is possible to record an image at any resolution regardless of the resolution of the two-dimensional array light source or the magnification of the imaging optical system. An object of the present invention is to provide an image recording method capable of significantly reducing image quality deterioration caused by an aberration error or the like of an optical system, and an image recording apparatus using the image recording method.

[0009]

In order to achieve the above object, an image recording method of the present invention is set when an image formed by a light source group arranged two-dimensionally is recorded on a recording medium. During recording, the image recording position on the recording medium by the light source group is set to at least one of the two-dimensional array direction of the light source group according to the change magnification of the resolution per one recording pixel of the light source group. Provided is an image recording method characterized by moving in a direction including a component, and correspondingly to this movement, modulating each pixel of the light source group according to a recording image and recording the image on the recording medium. To do.

Further, the image recording apparatus of the present invention has a two-dimensional array light source having two-dimensionally arrayed recording pixels and a set change magnification of the resolution per one recording pixel of the two-dimensional array light source. Accordingly, during recording, the image recording position on the recording medium by the two-dimensional array light source is moved in a direction including at least one component of the recording pixel array direction of the two-dimensional array light source, and the moving means. According to the movement of the image recording position by the above, there is provided an image recording apparatus comprising: a modulation unit that modulates each recording pixel of the two-dimensional array light source according to a recording image.

In the present invention as described above, it is preferable that the moving means moves the image recording position in a direction including both components of the recording pixel array direction of the two-dimensional array light source, and the moving means. Is for moving the image recording position in units of the recording pixels of the two-dimensional array light source, and the one recording pixel array direction of the two-dimensional array light source is the A direction and the other recording pixel array direction is the B direction. Direction, A
When the resolution change magnification in the direction is a and the resolution change magnification in the B direction is b, it is preferable to move the image recording position by b pixels in the A direction or a pixels in the B direction. It is preferable that the modulation unit performs a × b times of modulation evenly in time division when the image recording position is moved by the moving unit. Further, b pixels in the A direction and B pixels are formed.
It is preferable to move the image recording position by a pixels in the direction, and the number of moving pixels in the A direction and the number of moving pixels in the B direction are integers of 1 for one and 2 or more for the other.
Alternatively, it is preferable that the number of moving pixels in the A direction and the number of moving pixels in the B direction are mutually prime integers of 1 or more.

Further, in the present invention as described above, a main scanning means for relatively moving the two-dimensional array light source and the recording medium in a main scanning direction which coincides with one recording pixel array direction in the two-dimensional array light source. A sub-scanning unit that relatively moves the two-dimensional array light source and the recording medium in a sub-scanning direction orthogonal to the main scanning direction; and an image recording position by the two-dimensional array light source, It is preferable to have a two-dimensional array light source and a tracking unit that follows the relative movement of the recording medium, and to record the image by arranging the image by the two-dimensional array light source in the main scanning direction and the sub-scanning direction. Furthermore, it is preferable that the main scanning direction and the sub-scanning direction coincide with the A direction and the B direction.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The image recording method and image recording apparatus of the present invention will be described below in detail with reference to the preferred embodiments shown in the accompanying drawings.

FIG. 1 shows a schematic perspective view of an example of the image recording apparatus of the present invention for carrying out the image recording method of the present invention.
The image recording apparatus 10 shown in FIG.
Is a recording pixel (light source group) arranged two-dimensionally.
As a two-dimensional array light source having a two-dimensional array light source, a two-dimensional array light source in which a two-dimensional spatial light modulator and a light source for illuminating the two-dimensional spatial light modulator are combined is used. drum)
By arranging the projection light from the DMD 12 on the recording medium Pt by using and, the recording medium Pt is two-dimensionally exposed to record an image.

The recording apparatus 10 as described above basically has a light source (not shown) for emitting illumination light, a digital micromirror device 12 (hereinafter referred to as DMD 12) which is a two-dimensional spatial light modulator, and a collimator. Lens 14,
The optical deflector 16, the focusing lens 18, the sub-scanning drive system 20, the external drum 22 (hereinafter referred to as the drum 22), and the control means (not shown) for these are configured. A recording medium Pt is wound around the outer surface of the drum 22 and is held / fixed by a known means.

As a light source, a sufficient amount of light (illumination light)
Any light source that emits light according to the spectral sensitivity characteristic of the target recording medium Pt can be used as long as it can emit light. For example, if the recording medium Pt is a normal PS plate (conventional PS plate) that can be exposed to ultraviolet light, an ultrahigh pressure mercury lamp, a metal halide lamp, or the like may be used. Further, when the recording medium Pt is a heat mode recording medium having sensitivity to infrared light (heat), an infrared broad area laser diode (LD) or the like may be used. Other than these, a halogen lamp, a xenon lamp, or the like can be used depending on the recording medium Pt.

As is well known, the DMD 12 is a two-dimensional spatial light modulation element in which rectangular micromirrors that can rotate (swing) about a predetermined rotation axis by a predetermined angle are arranged two-dimensionally. By electrically rotating the micromirror,
The light is modulated for each micromirror (= pixel) to turn exposure on / off. In the recording device 10 of the illustrated example,
As an example, when the pixel interval is 17 μm, 1024 pixels × 1
A 280 pixel DMD 12 is used. Further, the rotation direction of the drum 22 (direction of arrow R in the figure) and the DMD 12 described later
The respective members are arranged so that one of the pixel row directions of the above is optically coincident with each other, and the axis line of the drum 22 and the other pixel row direction are optically coincident with each other. Hereinafter, the pixel column direction (the arrow Y direction in the drawing) of the DMD 22 which is the reverse direction of the rotation of the drum 22 is the main scanning direction, and the right direction (the arrow X direction in the drawing) in the axial direction of the drum is the sub scanning direction.

As described above, in the illustrated example, the DMD
A two-dimensional array light source is configured by combining 22 and the light source. Here, in the present invention, the two-dimensional spatial light modulator that constitutes the two-dimensional array light source is DMD2.
Besides 2, the liquid crystal shutter array in which liquid crystal shutters are two-dimensionally arranged, PLZT type, EO type, AO type, GLV type, etc. can be used. Further, in the present invention, the two-dimensional array light source is not limited to a combination of such a light source and a spatial light modulator. For example, an array light source in which point light sources such as LEDs are two-dimensionally arranged, a CRT or a backlight LC
A self-luminous display such as D (liquid crystal display) may be used as the two-dimensional array light source. However, as the two-dimensional array light source, the one in which the DMD 12 and the light source are combined is most preferable in terms of the modulation speed and the light utilization efficiency.

The collimator lens 14 makes the image-bearing light reflected by the DMD 12 incident on the optical deflector 16 as parallel light.

The light deflector 16 deflects the light incident through the collimator lens 14 in the substantially rotating direction of the drum 22 to generate DM as shown in FIG.
The incident position (image recording position) of the projection light on the recording medium Pt by D12 is set to DMD12 on the recording medium Pt to be main-scanned.
It is a follower that follows the projection light from. That is, the light deflector 16 basically deflects the projection light from the DMD 12 carrying an image in the drum rotation direction in synchronization with the rotation of the drum 22, thereby rotating the projection light. And is stopped at a fixed position on the recording medium Pt for a predetermined recording time (exposure time). In the following description, the DMD 12 on the recording medium Pt is used.
Of the projection light of the frame F, and one image recording by the frame F stopped on the recording medium Pt by the deflection of the optical deflector 16
Record the frame. Therefore, one frame has a size of one screen (a range in which the DMD 12 can be exposed at one time) on the recording medium Pt by the DMD 12.

Here, in the present invention, the image recording position on the recording medium Pt is moved in a direction including at least one of the pixel arrangement directions of the two-dimensional array light source during image recording (exposure). In the recording device 10, the DMD 1
The optical system is configured such that the pixel arrangement direction of 2 and the main scanning direction and the sub-scanning direction are optically matched, and in a preferred mode, the optical system is stationary on the recording medium Pt.
During image recording of a frame, the frame F is moved in a direction including both components in the main scanning direction and the sub scanning direction (hereinafter, referred to as both main and sub components).
(The incident position of the projection light from the DMD 12) is moved. Hereinafter, the movement of the frame F during the recording of one frame is referred to as “shifting the frame F”.

In the recording apparatus 10 of the illustrated example, as a more preferable aspect, the optical deflector 16 which is the following means also serves as the moving means for shifting the frame F. Therefore, the deflection direction of the optical deflector 16 has a slight angle with respect to the rotation direction (main scanning direction). Such a light changer 16
The operation of will be described in detail later.

The optical deflector 16 is a galvanometer mirror,
Polygon mirror, piezo system, lens drum 22
Various types such as an optical deflector that shifts in the rotation direction of the can be used. In the recording apparatus 10 of the illustrated example, a galvanometer mirror (hereinafter referred to as a galvanometer mirror) is used as a suitable example.

The focusing lens 18 is used for the optical deflector 1.
The projection light of the DMD 12 deflected by the
The image is formed at a predetermined position on the recording medium Pt that is wound around 2.

The drum 22 has a recording medium Pt on its outer surface.
Is a cylinder which is held / fixed by a known method in a state of being wound, and which rotates about an axis in a direction indicated by an arrow R opposite to the main scanning direction. As a result, the DMD 12 (two-dimensional array light source) and the recording medium Pt relatively move in the main scanning direction (that is, main scanning is performed). In the present invention, the target recording medium Pt is not particularly limited, and may be a light-sensitive material or a heat-sensitive material, and may have a film shape or a plate shape.

From the light source to DMD 12, collimator lens 1
4, the optical deflector 16, and the optical system reaching the focusing lens 18 are integrally unitized, and are moved at a constant speed in the sub-scanning direction (the arrow X direction in the drawing) by the sub-scanning drive system 20. As a result, the DMD 12 and the recording medium Pt relatively move in the sub scanning direction (that is, the sub scanning is performed). The sub-scanning drive system 20 is a known one used in so-called drum scanners and the like. For example, a drive source (not shown), a movable table 20a on which a unitized optical system is mounted, and this movable table 20a To move,
The moving shaft 20b extends in the sub-scanning direction.

In the present invention, the means for holding the recording medium Pt and performing the main scanning and the sub-scanning is not limited to the (external) drum 22 as shown in the drawing, and the recording medium Pt can be used even in a flat bed. It may be an internal drum that holds the inside.

FIG. 2 shows a block diagram of the recording timing control of the recording apparatus 10. As shown in FIG. 2, the light source 24,
The optical system such as the DMD 12 and the optical deflector 16 (the collimator lens 14 and the focusing lens 18 are omitted in FIG. 2) is integrally configured, and at least during image recording,
The sub-scanning drive system 20 continuously moves in the sub-scanning direction X at a constant speed.

As described above, during recording of the image, the recording medium P is
While the drum 22 holding t rotates, the optical deflector 1
6 is a frame F (projection light from the DMD 12)
By deflecting in the substantially main scanning direction in synchronization with the rotation of 2, the frame F is kept stationary on the recording medium Pt for a predetermined recording time and one frame is recorded. Further, during image recording, the optical system unit is conveyed in the sub-scanning direction by the sub-scanning drive system 20. A main scanning position detector 26 is provided on the drum 22 to control the timing, and
The sub-scanning drive system 20 is provided with a sub-scanning position detector 28 that detects the sub-scanning position. Main scanning position detector 26
For example, a rotary encoder that detects the rotational position of the drum 22 can be used.

The DMD 12 is connected to a modulation signal generator 30 which supplies image data for one frame (on / off of each micromirror). The modulation signal generator 30 includes
The image signal is input, and the DMD 1 is detected based on the detection signals from the main scanning position detector 26 and the sub scanning position detector 28.
The image signal to be sent to 2 is switched. In addition, the optical deflector 1
An optical deflector driver 32 is connected to 6. The optical deflector driver 32 drives the optical deflector 16 based on the detection signals of the main scanning position detector 26 and the sub scanning position detector 28, and causes the projection light from the DMD 12 to match the relative movement of the recording medium Pt. To deflect.

In the recording apparatus 10 as described above, the image of one frame which is statically recorded on the recording medium Pt by being followed by the optical deflector 16 as described above is recorded on the recording medium P.
Images are recorded so as to be arranged in the image recording area of t.

Here, in image recording, the drum 22 is rotated once while the sub-scanning is stopped to form one row of one frame image by the DMD 12 in the main scanning direction (Y direction), and then the sub-scanning drive system 20. Recording is performed by moving the DMD 12 (optical system) in the sub-scanning direction by the size of one frame in the sub-scanning direction and repeating image recording for one row in the main scanning direction again. An image may be recorded by arranging the frames F on the entire surface of the medium Pt (in this case, the sub-scanning speed is 0). However, in the illustrated example, in order to reduce the recording time for one image and to reduce the load on the sub-scanning drive system 20, as a preferable mode, image recording is performed while continuously performing sub-scanning as described above. Go and drum 22
The frames F are arranged in a spiral pattern on the recording medium Pt that is wound around, and image recording is performed on the entire surface.

That is, in the recording apparatus 10 of the illustrated example, at the time when the drum 22 makes one revolution, the frame F to be recorded and the previously recorded frame F and the sub-frame F are recorded according to the rotation speed (main scanning speed) of the drum 22. The sub-scanning speed by the sub-scanning drive system 20 is set so as to be adjacent to each other in the scanning direction. As a result, spiral image recording is performed on the recording medium Pt wound on the drum 22, and the frames F are arranged in a stepwise manner in the main scanning direction as shown in the conceptual diagram of FIG. Then, image recording is performed on the entire surface of the recording medium Pt. In FIG. 3, the lower part shows the recording at the first rotation of the drum 22, the upper part shows the recording at the second rotation, and Ldr shows the length of one round of the drum 22. This recording method is described in Japanese Patent Application No.
No. 00-316622.

Here, in the recording apparatus 10 of the illustrated example, as described above, the projection light of the DMD 12 is deflected in the main scanning direction by the optical deflector 16 in synchronization with the rotation of the drum 22, thereby recording medium. The frame F is stopped on Pt and one frame is recorded. However, when image recording is performed while continuously performing sub-scanning, the optical deflector 16 moves in the main scanning direction.
Even if the frame F can be stopped by the deflection due to, the position of the frame F on the recording medium Pt moves in the sub-scanning direction, and the image is blurred. Therefore, in the recording device 10,
According to the positional deviation of the frame F due to the sub-scanning, the deflection direction is tilted in the sub-scanning direction with respect to the main scanning direction, and the frame F is more preferably kept stationary on the recording medium Pt during recording of one frame. Is preferred.

Here, as for the angle of the deflection direction with respect to the main scanning direction (direction of arrow Y), after recording one frame, the frame F to be recorded next has a pixel pitch in the sub-scanning direction (recording medium P).
It is preferable to set to move in the sub-scanning direction by an integral multiple of (pixel pitch on t). In particular, an integer multiple of the pixel pitch is Ny, the number of pixels in the main scanning direction for one frame is Nimg-y, and the pixel pitch in the main scanning direction for one frame is Pim.
gy When the pixel pitch of one frame in the sub-scanning direction is Pimg-x, it is preferable that the angle ψ of the deflection direction with respect to the main scanning direction satisfies the following formula. tan ψ = (Ny × Pimg-x) / (Nimg-y × Pimg-y
) Regarding this image recording method, Japanese Patent Application No.
No. 01-116470.

As described above, in the recording device 10,
Image recording of one frame is performed in a state in which the frame F (projection light of the DMD 12) follows the movement of the recording medium Pt and basically remains stationary on the recording medium Pt for a predetermined recording (exposure) time. Here, the recording apparatus 10 of the illustrated example is related to the present invention, and as conceptually shown in FIG. 4, during recording of one frame, the image recording position on the recording medium Pt, that is, the position of the frame F is changed. , A pixel (mirror) of the DMD 12 at a position where an image is to be recorded on the recording medium Pt in accordance with an image to be recorded in one frame while being shifted (moved) in a direction including both main and sub-components (direction of arrow V). When is located, the display image by the DMD 12 is modulated so that this pixel is turned on. In other words, a relative speed difference is given to the movement of the frame F for keeping still (corresponding to the recording medium Pt) corresponding to the main scanning and the sub-scanning between the recording medium Pt and the optical system, and this Accordingly, each pixel of the DMD 12 is modulated according to the image to be recorded. In the present invention, by having such a configuration, it is possible to change the resolution in image recording using a two-dimensional array light source.

The recording apparatus 1 will be described below with reference to FIGS.
The operation of image recording at 0 (invention) will be described. Figure 5
FIG. 5A conceptually shows a part of the frame F formed by the DMD 12 on the recording medium Pt, and FIG. 5B conceptually shows an example of the resolution of an image recorded on the recording medium Pt. both,
One square has one pixel, that is, one pixel of the frame F on the recording medium Pt (resolution of the DMD 12) is different from one pixel of the target image (resolution of recording). Each pixel of the frame F on Pt and the recorded image have the relationship shown in FIG.

In this example, the pixel (mirror) of the DMD 12 whose center is included in the recorded image is turned on to record the image. That is, for example, if the image to be recorded is the image indicated by the thick frame in FIGS. 5B and 5C, D indicated by the crosshatch in which the center indicated by the black dot is included in the image recording area.
The pixel of MD12 is turned on. Here, the pixel whose center is included in the image recording area is changed by the shift of the frame F in the direction including both the main and sub components during the recording of one frame. In the present invention, the image is recorded by switching, that is, modulating the image displayed by the DMD 12 accordingly.

5A and 5B by a part of the frame F (projection light of the DMD 12) by the DMD 12 shown in FIG. 5A.
An example of the recording of the image indicated by the thick frame in (B) will be described with reference to FIGS. 6 to 8. In this example,
As an example, as shown in FIG. 4, during recording of one frame, three pixels in the main scanning direction (arrow Y direction), one pixel in the sub scanning direction (arrow X direction), and a frame F are recorded. Shift. That is, the image is recorded by shifting the frame F in the main scanning direction: the sub scanning direction = 3: 1. In this example, as an example, the actual moving direction of the frame F is opposite to the main scanning direction and the sub-scanning direction, but the present invention is not limited to this. Further, in the recording of one frame, the recording time (exposure time) is equally time-divided, and the display image of the DMD 12 is changed nine times, that is, the modulation is performed nine times.

As an example, recording of one frame is started from the state shown in FIG. In this state, the pixels a-3 and b-3 of the DMD 12 are displayed in the area of the recorded image indicated by the thick frame.
And the centers of c-1 to c-3 are included, the pixel is turned on and an image is recorded as shown by a cross hatch.

As described above, the recording medium Pt held on the drum 22 is rotated in the direction opposite to the main scanning direction. Further, the frame F is deflected in the same direction by the optical deflector 16 so that it is basically followed / still by the recording medium Pt, and is shifted in the direction containing both the main and sub components at the ratio of 3: 1. ing. 1/9 of the recording time for one frame has passed, that is, 3/9 pixels in the main scanning direction (arrow Y direction),
When the frame F is shifted by 1/9 pixel in the sub-scanning direction (direction of arrow X) (hereinafter, simply "the frame F is shifted by a predetermined amount"), as shown in FIG.
2 is modulated and the image (projected image) is switched. That is, since the center of the pixel a-3 included in the recording start state deviates from the recording image area, only this pixel is turned off from the state shown in FIG. 6A.

When the frame F is further shifted by a predetermined amount, FIG.
As shown in (C), the DMD 12 is modulated to turn off the pixel c-1 whose center is out of the recorded image area and turn on the pixels d-2 and 3 whose center is newly entered in the recorded image area. . When the frame F is further shifted by a predetermined amount, the result shown in FIG.
As shown in (D), the DMD 12 is modulated, and the pixel c-2 that is out of the center of the recorded image area is turned off.

Thereafter, similarly, FIG. 7E to FIG.
As shown in (I), every time the frame F shifts by a predetermined amount, the DMD 12 is modulated, the pixel whose center is out of the recording image area is off, and the pixel whose center is in the recording image area is o.
n to record the image. Finally, when the frame F is shifted by a predetermined amount from the state shown in FIG. 8 (I) to reach the state shown in FIG. 9, the frame F is shifted by 3 pixels in the main scanning direction and by 1 pixel in the sub scanning direction. That is, the recording of one frame is completed, all the pixels are turned off, and the pixels are arranged adjacent to each other in the main scanning direction according to the movement of the recording medium Pt (rotation of the drum 22) and the state of the optical deflector 16. Image recording of the next frame is started.

That is, in the recording of one frame shown in FIGS. 6A to 9, the recording is performed so that the areas shown by the cross hatches in FIGS. 6A to 8I overlap, that is, The image is recorded as conceptually shown in FIG. As shown in FIG. 10, in the image recording method of the present invention, the image recording is performed up to an area slightly exceeding the ideal resolution of the target recording image, but the recording is performed in the target image recording area. Since the amount of recording (exposure) in the protruding portion is concentrated, there is no problem in terms of image quality.

In the conventional image recording using a two-dimensional array light source, one pixel of the two-dimensional array light source (DM in the illustrated example is used.
Only a resolution that is an integral multiple of 1 pixel of the projection light of D12 can be expressed, and in order to express resolutions other than this, it is necessary to prepare a zoom lens and a plurality of imaging optical systems with different magnifications. It was

On the other hand, as is apparent from the above description, according to the present invention, the coma F (projection light of the two-dimensional array light source) is recorded in the image recording using the two-dimensional array light source utilizing the DMD 12 or the like. By shifting (moving) in the direction including both the main and sub components, and modulating the two-dimensional array light source according to the image to be recorded, image recording similar to so-called scanning exposure can be performed.

Therefore, according to the present invention, each pixel of the two-dimensional array light source is modulated according to the target resolution and image, regardless of the resolution of the two-dimensional array light source, and thus the zoom lens or the plurality of types of light sources are modulated. Even without using an imaging system, any number of resolutions other than the multiple of the two-dimensional array light source, for example, 2540 dpi, 2438 dpi and 240 as described above.
Image recording can be performed corresponding to three types of resolution of 0 dpi. Further, since the resolution can be adjusted, even if there is an error in the imaging optical system or the two-dimensional array light source, it is possible to appropriately correct and record an image of a predetermined resolution.
The size change of the recording medium Pt due to the temperature change can be easily dealt with. Moreover, according to the present invention that performs such scanning exposure, the adverse effect of the distortion of the projection light due to the distortion aberration of the imaging optical system can be greatly reduced, and the image quality is not deteriorated due to the distortion. It can record various images.

An example of the method of modulating the DMD 12 (two-dimensional array light source) in image recording while shifting the frame F will be described below with reference to FIG. Further, FIG. 12 shows an example of a control block diagram for executing this modulation method.

As shown in the upper left part of FIG. 11, the DMD
In the pixel array direction of 12, the i-th pixel in one direction and the j-th pixel in the other direction are defined as pixel (i, j).
In the illustrated example, i is the sub-scanning direction (X direction).
And j corresponds to the main scanning direction (Y direction). Further, the pixel pitch of the DMD 12 in the main scanning direction is Δy, and the pixel pitch of the sub scanning direction is Δx. Therefore, (i * Δx, j
* Δy) gives the center position (x) of this pixel (i, j)
_i , y _j ) can be obtained.

A function indicating the shift amount in the sub-scanning direction is Fx,
The function indicating the shift amount in the main scanning direction is Fy. this
According to the DMD1 at time t during the recording of one frame.
2 center position (x) of the pixel (i, j)_i, Y_j) Throw
The position on the image is (Fx (x _i, Y_j, T), Fy (x
_i, Y_j, T)). Below this position
To the image center position (X_i, Y_j). 12 shown in FIG.
In the lock diagram, these functions correspond to Fx and Fy.
Using a shift amount determination LUT (lookup table)
Image center position (X_i, Y_j) Is getting. In addition, this
The functions Fx and Fy (decision LUT) are all the shift amounts.
In consideration of the distortion of the focusing lens 18, etc.
May be set by this, so that a two-dimensional array light source is used
Image recording, the resolution changes due to frame shift.
At the same time, lens aberration correction can be performed.

On the other hand, in the output resolution of the image to be recorded, the pixel pitch in the main scanning direction is ΔY and the pixel pitch in the sub scanning direction is ΔX. As described above, the center position (x _i , y _j ) of the pixel (i, j) of the DMD 12 becomes the image center position (X _i , Y _j ) on the projected image. Therefore, by dividing the image center position by the pixel pitch, it is possible to know at which pixel on the bitmap of the recorded image the image center position is located, and (round [(X _i / ΔX) +0. 5], roun
If d [(Y _j /ΔY)+0.5]) corresponds to the on pixel (m _on , n _on ) _on the image bitmap of the image to be recorded, the pixel (i, j) is turned _on . DMD1
If 2 is modulated, image recording as illustrated in FIGS. 6 to 9 can be performed. In the above equation, "round
] Indicates rounding. In this example, as an example,
In the image bitmap, m corresponds to the sub scanning direction and n corresponds to the main scanning direction.

Here, in image recording using a two-dimensional array light source such as the recording device 10, shading occurs due to variations in the projected image size of each pixel, variations in light intensity, position errors, and the like. . For example, in the case of printed matter, the shading causes variations in the reproduced half-tone (locality depending on the position of the area ratio), which is a problem in image quality, and correction is necessary. Normally, the shading correction is performed by correcting the light intensity of each pixel, but according to the recording method of the present invention in which the frame F is shifted and recording is performed,
Shading can be corrected by direct correction of the area ratio instead of intensity correction.

A position obtained by dividing the image center position by the pixel pitch ((X _i / ΔX, Y _j / ΔY) or less, which will be referred to as a DMD image) and an on pixel (m
_on , n _on ), the absolute value of the difference in the corresponding direction indicates the deviation of the central position between the DMD image and the on pixel. Therefore, this absolute value is compared with a threshold Thr (a positive number) that is appropriately set for each of the main and sub, and when the absolute value in both the main and sub directions is less than or equal to the threshold Thr, the pixel of the DMD 12 ( By controlling the modulation so that i, j) is turned on, the area ratio of the recorded image can be controlled. _{That, | (X i / ΔX)} -m on | ≦ Thr m | (Y j / ΔY) -n on | when satisfying ≦ Thr _n together, pixels of DMD 12 (i, j) to o
The area ratio of the recorded image can be controlled by controlling the modulation so as to control the area.

The threshold value may be appropriately determined according to the shading of the optical system. For example, Thr _m = Th
If r _n = 0.5, the standard image recording without the correction described above is performed, that is, the DMD image (X _i / Δ
X, Y _j / ΔY) is the on pixel (m
_In this example, the pixel (i, j) of the DMD 12 is turned on when it exists in _on , n _on ). On the other hand, Thr _m = Th
If r _n = 0.6, even if the DMD image deviates from the on pixel of the image bitmap by 0.1 pixel, the pixel remains on.
Therefore, the area ratio can be increased. On the contrary, Thr _m =
In the case of Thr _n = 0.4, unless the DMD image is present in a region smaller by 0.1 pixel than the on pixel of the image bitmap, that pixel is not turned on, and the area ratio is reduced. Further, when Thr _m and Thr _n are set to different values, the area ratio can be controlled in the main scanning direction and the sub scanning direction (vertical and horizontal of the image).

In the present invention, the direction and amount of shift of the frame F in the recording of one frame are basically appropriately determined depending on the target magnification of the resolution per pixel of the DMD 12. To be done. The recording device 1
At 0, the direction and amount of shift may be fixed, variable, or appropriately settable. Preferably, the frame F is shifted in units of pixels (pixel pitch) of the DMD 12 (two-dimensional array light source), and
One pixel arrangement direction of the DMD 12 is the A direction and the other is the B direction, and the resolution change magnification (division number) in the A direction corresponding to the desired resolution change magnification is a and the change magnification in the B direction (division number). ) Is set to b, and when recording one frame,
If there are b pixels in the A direction or a pixels in the B direction, the frame F
It is preferable that the shift is performed and the modulation is performed a × b times evenly in time division. More preferably, the number of shift pixels in the A direction and the B direction is set such that one is 1 and the other is an integer of 2 or more, or an integer of 1 or more which is relatively prime.

FIG. 13 conceptually shows the movement of each pixel (mirror) of the DMD 12 on the recording medium Pt in the image recording shown in FIGS. 6 to 9 described above. The recording apparatus 10 of the illustrated example has a two-dimensional pixel array direction of the DMD 12 and a main scanning direction (arrow Y direction) as a preferable mode.
And the sub-scanning direction (direction of arrow X) match,
In the present invention, either the A direction or the B direction may be the main scanning direction or the sub scanning direction. In the present invention, the A and B directions need not necessarily coincide with the main / sub-scanning directions. In the following description, for convenience, the sub-scanning direction is the A direction and the main scanning direction is the B direction,
It is assumed that the first modulation is performed at the start of shift (at the start of recording of each frame F).

As described above, in this example, in the recording of one frame, the frame F is shifted by A direction: B direction = 1 pixel: 3 pixels, and nine times of modulation are performed evenly in time division. ,
Each pixel of the DMD 12 moves as shown by the arrow, and modulation is performed at the position of the point. Here, focusing on the pixel position Pix of one pixel indicated by the arrow (the position of one pixel at the start of the shift of recording of one frame on the projected image of the DMD 12), when viewed in the B direction, In image recording, three pixels enter from the end portion in the B direction at equal intervals in the A direction and proceed to the end portion on the opposite side, and each of them has an equal interval, that is, a phase in the B direction (position in the B direction). ) Together 3
Modulated times. That is, in this example, three pixels are divided in the A direction into three parts (resolution is three times), and in the B direction are divided into three parts (three times in the same direction) by modulation of each pixel having the same phase. The position Pix is divided into 9 by 3 × 3, and the image is recorded with 9 pixels by performing modulation on each position, and thus the image is recorded with a resolution equivalent to 9 times the resolution of the DMD 12. .

Therefore, the number of divisions of one pixel (= resolution change magnification per pixel) and the state of division (the number of divisions in each of the A direction and the B direction) are set so that the trajectories of the respective pixels do not overlap. ) Depending on the resolution of the target image, etc.
By appropriately setting, in the image recording using the two-dimensional array light source, the image recording with the resolution conversion as shown in FIGS. 5 to 10 can be suitably performed.

Here, according to the study by the present inventors, in the image recording of the present invention in which the frame F is shifted and recording is performed, the image recording shown in FIG.
When there is a direction in which the number of shift pixels matches the number of divisions in the other direction (A direction), as in the B direction in 3,
When viewed in this direction (hereinafter, for convenience, referred to as the B direction according to FIG. 13), at the pixel position Pix, the same number of pixels as the number of shift pixels in the B direction advances in the A direction at equal intervals. . That is, at this time, the other division number a in the A direction matches the shift pixel number in the B direction. Further, as described above, the division number b in the B direction is the modulation number at the pixel position Pix. Therefore, if the modulation number in the recording of one frame is divided by the shift pixel number in the B direction, the division number b in the B direction is obtained. Conversely, the modulation number for recording one frame can be determined by the target division number b in the B direction and the shift pixel number. Here, as described above, in this case, the number of shift pixels in the B direction is equal to the number of divisions a in the A direction. That is,
The number of divisions a and b of the pixel position Pix is determined according to the target resolution, the number of shift pixels in one direction is made to match the number of divisions in the other direction, and the number of divisions a in the A direction and the number of divisions in the B direction are determined. If the modulation is performed a × b times by multiplying by b, the pixel position Pix
Can be divided into a desired number, and a desired resolution change can be realized.

Further, the number of shift pixels in the A direction and the B direction is set such that one is 1 and the other is an integer of 2 or more, or
By setting the integers which are relatively prime to each other, the coma F can be shifted without overlapping the trajectories of the pixels.

Therefore, by utilizing this, one pixel can be arbitrarily divided and the target resolution per pixel can be changed.

Hereinafter, a more detailed description will be given with reference to FIG. It should be noted that in FIG. 14, the shift direction is in the upper direction, which is the opposite of the previous example, but there is no difference in the action and effect of both, as is apparent by observing by inverting the top and bottom. Also, in FIG. 14, the shift direction is the right direction, but as is clear by observing the paper surface upside down,
Even if the shift direction is the right direction, the same effect is obtained. Further, in FIG. 14, although the pixel pitch is different between the A direction and the B direction (the pixels are different), the same is true even if the pixels are isotropic as in the previous example.

The example shown in FIG. 14 is a DMD 12 having pixels (projected image thereof) as shown in FIG.
In the (two-dimensional array light source), one pixel has 3 pixels in the A direction (a = 3) and 4 pixels in the B direction (12 = b = 4).
This is an example of dividing into pixels, that is, performing image recording at a resolution equivalent to 12 times, that is, the resolution in the A direction is 3 times, and the resolution in the B direction is 4 times. Therefore, in recording one frame, the number of shift pixels in the A direction (An) is set to 4 pixels, or the number of shift pixels in the B direction (Bn) is set to 3 pixels, and the frame F is shifted and the modulation number (Mn) is set. ) Is a × b = 3 × 4 = 12
If the time division is performed evenly and modulation is performed once, the target 12 divisions of A direction × B direction = 3 × 4 can be realized.

In the example shown in FIG. 14B, the number of shift pixels Bn in the B direction is the same as the number of divisions a in the A direction, that is, three pixels, and the number of shift pixels An in the A direction is one pixel. . Focusing on the pixel position Pix, in the B direction in which the number of shift pixels matches the number of divisions in the A direction (a = 3), three pixels progress at equal intervals in the A direction, which causes the pixel position Pix.
ix is divided into three in the A direction. On the other hand, in order to divide into four in the B direction, it is sufficient to perform modulation four times for one pixel, so in the present example in which the number of shift pixels Bn in the B direction is 3, the modulation number Mn is 4 × Bn. = 4 × 3 = 12. Here, as described above, the number of shift pixels Bn in the B direction is A
It is equal to the division number a in the direction (Bn = a). Therefore, the modulation number Mn may be a number obtained by multiplying the number of divisions in one pixel in the A direction and the B direction (Mn = b × Bn = a × b).
As a result, the pixel position Pix becomes A as shown by the dotted line.
12 divisions of direction × B direction = 3 × 4 can be realized.

As shown in FIG. 14C, similarly to the above, the number of shift pixels Bn in the B direction is the same as the number of divisions a in the A direction, which is 3, and the number of shift pixels An in the A direction is 2 pixels. It is an example. Similar to the previous example, the number of shift pixels in the B direction,
The number of divisions in the A direction matches (Bn = 3 = a), and the number of modulations in recording one frame is a × b = 12. Here, looking at the pixel position Pix, among the three pixels advancing in the B direction, the pixel on the right side of the drawing is the recording position P during the shift.
Exit from ix. However, another pixel enters the pixel position Pix from the same position on the left side in the B direction and is modulated in phase with the other pixel. Therefore, also in this example, in the B direction, three pixels at equal intervals in the A direction are always advanced, and the pixel is divided into three in the A direction.
ix is divided into 12 by A direction × B direction = 3 × 4.

In the example shown in FIG. 15A, the number of shift pixels An in the A direction is 4, which is the same as the number of divisions b in the B direction, and B
This is an example in which the number of shift pixels Bn in the direction is 1. Similarly, the number of times of modulation is 12 times. In this example, since the shift pixel number An in the A direction and the division number b in the B direction are equal to each other, the pixel position Pix is divided into four in the B direction by pixels advancing in the A direction. Further, the four pixel elements whose phases are aligned in the A direction are modulated three times in the A direction, whereby the pixel position Pi is divided into three in the A direction.
x is divided into 12 by A direction × B direction = 3 × 4.

Similarly, the example shown in FIG.
The number of shift pixels An in the direction is 4 which is the same as the number of divisions b in the B direction.
In this example, the number of shift pixels Bn in the B direction is the same as the number of divisions in the A direction, which is 3. Similarly, the number of modulations is 12
Times. In this example, since the number of shift pixels is the same as the number of divisions in the other direction in both the A direction and the B direction, when viewed in the A direction, the pixel position Pix depends on the pixels advancing in the A direction in the B direction. It is divided into four. Also in this example, A
Pixels advancing in the direction exit from the recording position Pix during the shift, but other pixels enter in synchronization in the same manner as in the example shown in FIG. 14C, so that the pixels are always equally spaced in the A direction. The four pixels of No. 4 progress and are divided into four in the B direction. Further, the four pixel elements whose phases are aligned in the A direction are divided into three in the A direction by three times of modulation, whereby the pixel position Pix is A direction × B direction = 3, as in the above-described examples. It is divided into 12 by 4.

The example shown in FIG. 16 is an example in which the number of shift pixels Bn in the B direction is 3, which is the same as the number of divisions a in the A direction, and the number of shift pixels An in the A direction is 5. Similarly, the number of times of modulation is 12 times. In this example, since the number of shift pixels Bn in the B direction and the number of divisions a in the A direction are equal to each other, the pixel position Pix is similarly divided into three in the A direction by the pixels advancing in the B direction. . Also in this example, B
The pixel advancing in the direction exits from the recording position Pix during the shift, but like the example shown in FIG. 14C, other pixels enter in a synchronized manner, so that the B direction is always in the A direction. Then, three pixels at equal intervals progress, and it becomes the same as that divided into three in the A direction. In addition, 3 with the phase aligned in the B direction
By modulating each pixel four times, it is divided into four in the B direction, which allows the pixel position Pix to be divided in the same manner as in the previous examples.
Is divided into 12 by A direction × B direction = 3 × 4.

Here, in the present invention, FIG.
As shown in the example shown in FIG.
By making the number of divisions b in the direction equal and the number of shift pixels Bn in the direction B equal to the number of divisions a in the direction A, the modulation position in one pixel in the recording of one frame, that is, the modulation of each pixel. It is possible to align the phases of A in the A and B directions to form a square. As a result, the resolution can be changed (improved) uniformly in both A and B directions, which is often advantageous in terms of image quality. FIG. 17 shows another example.

FIG. 17A shows that one pixel is A
This is an example of 6 divisions in two directions (a = 2) in the direction B and three divisions in the direction B (b = 3). Number of shift pixels B
n is set to 2 which is the same as the number of divisions a in the A direction. further,
The modulation number Mn is 2 × 3 = 6 times. Pixel position Pix
In the same way as in the above example, when viewed in the A direction, the pixel position Pix is divided into three in the B direction by the pixels advancing in the A direction, and the pixel position Pix is A Direction is divided into two, A direction x B direction = 2 x 3
It is divided into 6 parts. The number of shift pixels in the A direction An
And the number of divisions b in the B direction are equal to 3, and the number of shift pixels Bn in the B direction and the number of divisions a in the A direction are equal to 2, the modulation phases in the A and B directions are square. There is.

Further, FIG. 17B shows that 1
Pixel is divided into three in the A direction (a = 3) and five in the B direction (b
= 5), the number of shift pixels in the A direction is set to 5 which is the same as the number of splits in the B direction, the number of shift pixels in the B direction is set to 3 which is the same as the number of splits in the A direction, and the number of modulations is set. Mn
Is 3 × 5 = 15 times. Similar to the previous example, A
When viewed in the direction, the pixel position Pix is divided into 5 in the B direction by the pixels advancing in the A direction, and is also divided into 3 in the A direction by three times of phase-aligned modulation. It is divided into 15 parts in the direction = 3 × 5. Further, the number of shift pixels An in the A direction is equal to the number of divisions b in the B direction, which is 5,
Moreover, since the number of shift pixels Bn in the B direction and the number of divisions a in the A direction are equal to 3, the modulation phases are aligned in the A direction and the B direction. In FIG. 17, the pixel position Pix is viewed in the A direction, but in the present example in which the number of shift pixels is the same as the number of divisions in the other direction, the pixel position Pix is also viewed in the B direction. , Exactly the same.

As is clear from the above description, DMD1
In image recording using 2 (two-dimensional array light source), the target division numbers a and b of one pixel (resolution change magnification)
According to the number of shift pixels in the B direction Bn = a or the number of shift pixels in the A direction An = b, and the number of modulations Mn
Is set to a × b, and further, An and Bn are efficiently shifted so that the recording resolution of the DMD 12 is improved by shifting the frame F under the condition that one is an integer of 1 and the other is an integer of 2 or more, or an integer that is relatively prime. It is possible to improve the image recording with the resolution converted as shown in FIGS. 5 to 10 described above.

According to the present invention, during the recording of one frame as described above,
By shifting (moving) the frame F (projection light) in a direction including both the A direction component and the B direction component, in the image recording using the two-dimensional array light source, an image recording with an arbitrary resolution which has been impossible in the past has been possible. Has been realized. The method of shifting the frame F on the recording medium Pt is not particularly limited, and various methods can be used. For example, a method of using the optical deflector 12, a method of providing a speed difference between the main scanning speed (peripheral speed of the drum 22) and the stationary state of the frame F, a sub-scanning speed and a following speed in the sub-scanning direction by the optical deflector. How to make a difference,
Examples include a method of moving the recording medium Pt (drum 22 in the illustrated example), a method of moving the optical system, a method of combining these, and the like.

As described above, the recording apparatus 10 of the illustrated example
With the following scan, the frame F is held still on the recording medium Pt 1
The frame is exposed, and the main scanning direction and the sub-scanning direction coincide with the pixel arrangement direction of the DMD 12, that is, the A direction and the B direction described above. In the recording apparatus 10, as a preferable mode, the optical deflector 16 which is a follower unit of the frame F in recording one frame also serves as a shift (moving) unit of the frame F. Therefore, the deflection direction of the optical deflector 16 is slightly tilted in the sub-scanning direction with respect to the main scanning direction. As a result, the following speed of the frame F with respect to the recording medium Pt has a relative speed difference with respect to the main scanning and the sub-scanning, and the frame F is subjected to both main and sub-components (that is, A direction and B direction) during recording of one frame. Is shifted in the direction including.

Here, the deflection direction and the like by the optical deflector 16 may be determined as follows, for example, in place of the target shift amount and direction, or further, the angle ψ described above.

If the peripheral speed of the drum 22, that is, the main scanning speed is Vy, a position Y (in the main scanning direction (arrow Y direction)) at one point on the recording medium Pt at a certain time t in the recording of one frame is performed. t) becomes “Y (t) = − Vy * t” as shown in FIG. On the other hand, when the deflection speed of the optical deflector 16 (galvano mirror in the illustrated example) on the recording medium Pt is Vy ′, there is a certain pixel (pixel of the DMD 12) on the recording medium Pt in one frame recording. Position Y ′ (t) in the main scanning direction at time t
Is "Y '(t) =-Vy' * t" as shown in FIG.
Becomes In the illustrated example, since the optical deflector 16 is a galvanometer mirror, the optical deflector 16 swings in the opposite direction after the recording time T has passed, and the position is indicated by the alternate long and short dash line.

If the recording time for one frame is T,
The shift amount in the main scanning direction in the above-described recording of one frame can be represented by the difference ΔY between the two. That is, ΔY = Y ′ (T) −Y (T) ΔY = −Vy ′ * T − (− Vy * T) Vy ′ = Vy− (ΔY / T)

On the other hand, in recording one frame, the recording medium P
The position of one point on t in the sub-scanning direction (direction of arrow X) at a certain time t does not move. On the other hand, the sub-scanning drive system 20
Is Vx, the position X (t) in the sub-scanning direction of a pixel at a certain time t due to the sub-scanning speed.
As shown in FIG. 18B, “X (t) = Vx *
t ”. Further, when the moving speed of a certain pixel in the sub-scanning direction by the optical deflector 16 is Vx ', a position X'of the certain pixel in the sub-scanning direction at a certain time t due to this is Vx'.
(T) is “X ′ (t) = Vx ′ *” as shown in FIG.
t ”.

Similarly, when the recording time for one frame is T,
The shift amount in the sub-scanning direction in the above-described recording of one frame can be represented by the difference ΔX between the two. That is, ΔX = X ′ (T) −X (T) ΔX = Vx * T−Vx ′ * T Vx ′ = Vx− (ΔX / T)

When viewed from the optical system (DMD12),
A certain point on the recording medium Pt is determined by the sub-scanning speed Vx and the peripheral speed Vy of the drum 22. Therefore, FIG.
As shown in FIG. 8 (C), in the recording of one frame with the recording time of T, the amount of shift is changed from the point determined by Vx * T and Vy * T depending on the main scanning speed and the sub-scanning speed. The optical deflector 16 may be set so that the light is deflected toward a position shifted by ΔX and ΔY.

Here, the angle formed by the main scanning direction and the deflection direction of the optical deflector 16 is θ, and the deflection speed of the optical deflector 16 is Vg.
Then, “Vx ′ = Vg * sin θ” and “Vy ′ = Vg * c”
Therefore, tan θ = (Vx ′ / Vy ′) = [Vx− (ΔX / T)] / [Vy− (ΔY / T)] = (Vx * T−ΔX) / ([Vy * T−ΔY) Becomes That is, the optical deflector 16 is designed to satisfy this.
By setting the angle, the main scanning speed (rotational speed of the drum 22), the sub-scanning speed, etc., in the recording of one frame, the shift of the frame F including both the target main and sub directions (A direction and B direction) can be performed. It can be carried out.

A method of shifting the frame F deflected by the optical deflector 16 in image recording in which one frame is recorded (exposure) by keeping the frame F stationary on the recording medium Pt by such follow-up scanning, The method of tilting the optical deflector 16 is not limited to this, and various methods can be used.

For example, by using an image rotating element such as a Dove prism, the projection light deflected by the optical deflector 16 is incident on the image rotating element, and the rotation angle of the image rotating element is adjusted to deflect the projection light. The frame F may be shifted by changing (rotating) the direction. FIG. 19 summarizes the relationship between the rotation angles (0 °, 90 °, 180 °, and 270 °) of the Dove prism, the image rotator prism, and the Pechan prism and the state of the optical path change of the incident light, that is, the shift state of the coma F. Indicate. Even if three mirrors are combined, the projection light can be shifted (rotated) like the image rotator prism.

Further, the optical deflector 16 is mounted on a goniometer stage having a rotation axis that optically coincides with the optical axis of the focusing lens 18, and the optical deflector 16 is rotated by adjusting the angle of the goniometer stage. Alternatively, the frame F may be shifted by adjusting the deflection direction of the projection light. Further, instead of this goniometer stage, a regulating member such as a pin is provided at a position corresponding to the center of rotation of the goniometer stage to regulate the rotation of the optical deflector 16 and to move the optical deflector 16 away from the regulating member. By pushing and pulling, the optical deflector 16
The frame F may be shifted by adjusting the rotation.

Although the image recording method and the image recording apparatus of the present invention have been described in detail above, the present invention is not limited to the above examples, and various improvements and changes are made without departing from the gist of the present invention. Of course you may go.

For example, the above example is an image recording apparatus for performing follow-up scanning for recording an image of one frame while keeping the projection light (frame) on the recording medium by deflecting the projection light of the two-dimensional array light source. However, the present invention is not limited to this,
For example, as shown in FIG. 19 described above, even in image recording in which multiple exposure is performed by moving (shifting) an image in a two-dimensional array light source, the projection light of the two-dimensional array light source is stopped on the recording material. , Can be suitably used. At this time, as an example, the shift of the same image from the most upstream pixel row to the most downstream pixel row in the main scanning direction of the two-dimensional array light source is regarded as one frame in the above-mentioned example, and one frame is similarly processed. It is only necessary to move the frame in the direction including the components in both the main and sub directions during the image recording.

Further, the present invention is not limited to recording one image by performing main scanning and sub-scanning as in the above-mentioned example and arranging images of one frame two-dimensionally. Instead, for example, one image may be recorded by recording one frame.

Further, in the illustrated example, the projection light of the two-dimensional array light source is shifted in a direction including both components in the pixel array direction of the two-dimensional array light source, but the present invention is not limited to this, and the pixel is not limited to this. By shifting the projection light in only one of the array directions,
The resolution may be arbitrarily changed only in this direction.

[0089]

As described above in detail, according to the present invention, a combination of a light source and a spatial modulation element such as a DMD, a light source in which point light sources such as LEDs are two-dimensionally arranged,
In image recording using a two-dimensional array light source having two-dimensionally arranged optical recording elements, it is possible to perform image recording with a plurality of arbitrary resolutions, and adverse effects due to distortion and the like of the optical system. It is possible to perform high-quality image recording, which is also excluded.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of an example of an image recording apparatus of the present invention.

FIG. 2 is a block diagram showing image recording timing control of the image recording apparatus shown in FIG.

FIG. 3 is a conceptual diagram for explaining image recording by the image recording apparatus shown in FIG.

FIG. 4 is a conceptual diagram for explaining image recording according to the present invention.

FIG. 5A is a conceptual diagram for explaining projection light by a DMD, FIG. 5B is a recording image, and FIG. 5C is a conceptual diagram for explaining image recording according to the present invention.

6A to 6C are conceptual diagrams for explaining image recording according to the present invention.

7 (D) to (F) are conceptual diagrams for explaining image recording according to the present invention.

8 (G) to (I) are conceptual diagrams for explaining image recording according to the present invention.

FIG. 9 is a conceptual diagram for explaining image recording according to the present invention.

FIG. 10 is a view conceptually showing an image by the image recording performed in FIGS. 6 to 9.

FIG. 11 is a conceptual diagram for explaining an example of image recording according to the present invention.

FIG. 12 is an example of a control block diagram for implementing the image recording method shown in FIG.

FIG. 13 is a diagram conceptually showing image recording in FIGS. 6 to 9.

14A is a conceptual diagram of one pixel for explaining the image recording of the present invention, and FIGS. 14B and 14C are conceptual diagrams for explaining an example of the image recording of the present invention. is there.

FIGS. 15A and 15B are conceptual diagrams for explaining another example of image recording in the present invention.

FIG. 16 is a conceptual diagram for explaining another example of image recording in the present invention.

17A and 17B are conceptual diagrams for explaining another example of image recording in the present invention.

18A to 18C are conceptual diagrams for explaining image recording in the image recording apparatus shown in FIG.

FIG. 19 is an illustration of a method of moving projection light in image recording of the present invention.

20A to 20C are conceptual diagrams for explaining image recording using a conventional two-dimensional array light source.

[Explanation of symbols]

10 (Image) recording device 11 light source 12 DMD 14 Collimator lens 16 Optical deflector 18 Focusing lens 20 Sub-scan drive system 22 (External) Drum 24 Photosensitive material 26 Main scanning position detector 28 Sub-scanning position detector 30 Modulation signal generator 32 Optical deflector driver Pt recording medium

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Takeshi Fujii             798 Miyadai, Kaisei-cho, Ashigarakami-gun, Kanagawa Prefecture             Shishi Film Co., Ltd. (72) Inventor Hiroshi Sunagawa             798 Miyadai, Kaisei-cho, Ashigarakami-gun, Kanagawa Prefecture             Shishi Film Co., Ltd. (72) Inventor Kouji Wada             798 Miyadai, Kaisei-cho, Ashigarakami-gun, Kanagawa Prefecture             Shishi Film Co., Ltd. F-term (reference) 2C162 AE28 AE37 AE48 AF57 FA09                 5C072 AA03 BA01 BA02 CA02 CA11                       RA20 TA04 XA07                 5C074 AA02 BB02 CC23 CC26 DD14                       GG04 HH02

Claims (9)

[Claims] 1. When recording an image formed by a two-dimensionally arranged light source group on a recording medium, recording is performed according to a set change magnification of resolution per recording pixel of the light source group. Inside, while moving the image recording position on the recording medium by the light source group in a direction including at least one component of the two-dimensional array direction of the light source group, corresponding to this movement, An image recording method, wherein each pixel is modulated according to a recording image and the image is recorded on the recording medium. 2. A two-dimensional array light source having recording pixels arranged two-dimensionally, and said two-dimensional array light source, during recording, according to a set change ratio of resolution per one recording pixel of said two-dimensional array light source. Moving means for moving the image recording position on the recording medium by the two-dimensional array light source in a direction including at least one component in the recording pixel array direction of the two-dimensional array light source, and movement of the image recording position by the moving means. An image recording apparatus comprising: a modulation unit that modulates each recording pixel of the two-dimensional array light source according to a recording image. 3. The image recording apparatus according to claim 2, wherein the moving means moves the image recording position in a direction including both components in the recording pixel array direction of the two-dimensional array light source. 4. The moving means moves an image recording position in units of recording pixels of the two-dimensional array light source, and one recording pixel array direction of the two-dimensional array light source is an A direction, When the other recording pixel array direction is the B direction, the resolution changing magnification in the A direction is a, and the resolution changing magnification in the B direction is b, b pixels in the A direction or a in the B direction.
The pixel or the image recording position is moved.
The image recording device described in 1. 5. The image recording apparatus according to claim 4, wherein the modulation unit performs a × b times of modulation evenly in time division when the image recording position is moved by the moving unit. 6. A pixel in the A direction and a pixel in the B direction,
The image recording apparatus according to claim 4, wherein the image recording position is moved. 7. The number of moving pixels in the A direction and the number of moving pixels in the B direction are integers in which one is 1 and the other is 2 or more, or the number of moving pixels in the A direction and the number of moving pixels in the B direction. The image recording apparatus according to claim 4, wherein is an integer that is relatively prime and is 1 or more. 8. A main scanning unit that relatively moves the two-dimensional array light source and a recording medium in a main scanning direction that coincides with one recording pixel array direction in the two-dimensional array light source, and the main scanning direction. A sub-scanning unit that relatively moves the two-dimensional array light source and the recording medium in an orthogonal sub-scanning direction, an image recording position by the two-dimensional array light source, a two-dimensional array light source and a recording medium by the main scanning unit. And a tracking unit configured to follow a relative movement of the two-dimensional array light source, and the images are recorded by arranging the images by the two-dimensional array light source in the main scanning direction and the sub-scanning direction. Image recording device. 9. The image recording apparatus according to claim 8, wherein the main scanning direction and the sub scanning direction coincide with the A direction and the B direction.