JP2000131776A - Printing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a picture printing device capable of reducing the restriction of the layout of optical parts and capable of being miniaturized while surely preventing interference from being caused between original light or image light and the various kinds of optical parts. SOLUTION: In this picture printing device, the original light emitted from a light source 8 is converted to the monochromatic light of R, G or B by a color wheel 9, condensed by an optical fiber 22 and made incident on a digital micro-mirror device 10. By properly setting the shape of the fiber 22, that means, the shape of the optical path of the original light, the layout of the various kinds of optical parts such as the light source 8, the wheel 9, the mirror device 10 and an enlargement lens 11 can be executed with the large degree of freedom. Besides, the device can be made compact.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus, and more particularly to a printing apparatus comprising a digital micromirror device and a large number of pixels displayed by a reflective digital image display device such as a reflective LCD (liquid crystal display). BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image printing apparatus which condenses light emitted from a light source when printing an image on a photosensitive material, and guides the light to an image display apparatus through a non-linear optical path.

[0002]

2. Description of the Related Art A reflection type digital image display device (for example, a digital micromirror device, a reflection type LCD, etc.) for displaying an image by reflecting light emitted from a light source (for example, a halogen lamp) is used. 2. Description of the Related Art An image printing apparatus in which an image composed of a large number of pixels displayed by the image display apparatus is printed on a photosensitive material (for example, photographic paper) is conventionally known.

In such an image printing apparatus, generally,
Light emitted from the light source (hereinafter referred to as "primary light")
Is irradiated (incident) on the image display device along a linear optical path while being condensed by the condenser lens. Then, the reflected light of the image display device, that is, the light accompanied by the image displayed by the image display device (hereinafter, referred to as “image light”) is stretched by a stretching lens (printing lens) to form a linear optical path. The light is then irradiated onto the photosensitive material (see FIG. 3B).

[0004]

However, in such a reflection type image display device, the angle between the optical axis of the incident light and the optical axis of the reflected light is relatively small (for example, depending on the reflection characteristics). (20 °), it is necessary to set the optical paths of the original light and the image light. In other words, various optical parts such as a light source and a stretching lens are used so that the angle between the optical path of the linear original light and the optical path of the linear image light (hereinafter, this is referred to as “optical path angle”) is the above angle. You need to lay out. However, when the optical path angle is reduced, a part of the image light is disturbed due to interference between the condensing lens and the image light, or interference occurs between the enlargement lens and the original light, and one of the original light is generated. Parts may be disturbed.

For this reason, in a conventional image printing apparatus using a reflection type image display apparatus, the layout of optical parts such as a light source and an enlargement lens is restricted, and the size of the image printing apparatus cannot be sufficiently reduced. There is a problem. For example, the condensing lens must be arranged at a position relatively distant from the image display device, so that the optical path length from the light source to the image display device becomes longer,
There is a problem that the image printing apparatus becomes large.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and is directed to light incident on a reflection type image display device from a light source or light irradiating a photosensitive material from the image display device with various types of light. An image printing apparatus (printing apparatus) capable of reducing restrictions on the layout of optical parts and reliably reducing the size of the apparatus while reliably preventing interference with optical parts. Providing is an issue to be solved.

[0007]

A printing apparatus (image printing apparatus) according to the present invention has been made to solve the above-mentioned problems.
Is provided with a reflective image display device that reflects the light emitted from the light source to display an image, and irradiates the photosensitive material with light with an image composed of a large number of pixels displayed by the image display device. In a printing apparatus which exposes the photosensitive material and prints the image on the photosensitive material, the light emitted from the light source is condensed to form a non-linear shape (for example, a curved shape, a broken line shape, etc.). Light guide means for guiding the image display device with the optical path (optical axis) of the present invention.

Here, the light guide means forms a non-linear optical path by, for example, an optical fiber (which can be bent or bent freely) or a mirror tunnel, or (one or more) prisms. Is preferred.

In this printing apparatus, the optical path of the original light from the light source to the image display device can be set in a non-linear shape with an arbitrary shape. It is possible to lay out the optical parts with a large degree of freedom while reliably preventing interference between optical parts such as various lenses and original light or image light, and to miniaturize the apparatus. it can. Further, in the conventional printing apparatus, optical parts such as a condenser lens, which are necessary for condensing the original light, are not required. Further, since the optical path length between the light source and the image display device can be shortened, the light use efficiency is improved.

In the above printing apparatus, the exposure process may be performed while moving the photosensitive material. In this case, the exposure processing is usually performed by a line exposure method. Here, the line exposure is a process in which the photosensitive material is continuously moved by the transporting means, and each of the strip-shaped (elongated rectangular) exposure processing areas is elongated in a direction perpendicular to the photosensitive material transport direction (that is, the photosensitive material width direction). Is an exposure processing method for sequentially performing exposure processing. As the line exposure, there are literally an exposure method of exposing one line (one line) at a time and a plurality of lines (scrolling an image of an image display device in the photosensitive material transport direction in synchronization with movement of the photosensitive material). Any of the exposure methods of simultaneously performing exposure over a plurality of rows can be used.

In the above printing apparatus, the exposure processing may be performed with the photosensitive material stopped. In this case, the exposure processing is usually performed by a surface exposure method. In addition, the surface exposure means that the photosensitive material is intermittently moved by the transport means, and the exposure processing is performed on a planar (for example, rectangular) exposure processing area (for example, an exposure area for one frame) when the movement of the photosensitive material is stopped. This is an exposure method to be applied.

In this printing apparatus, various kinds of reflection-type digital image display devices can be used as the image display device. Specifically, for example, a digital micromirror device (DMD), a reflective LCD, or the like can be used. Note that the digital micromirror device includes a plurality of micromirrors that can switch the reflection direction, and the image can be displayed by switching the reflection direction of each micromirror so as to correspond to the image. A reflective image display device that can be used, and is particularly suitable for use as an image display device of a printing apparatus according to the present invention.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image printing apparatus (printing apparatus) using a digital micromirror device (DMD) as a reflection type image display device and using an optical fiber as a light guiding means from a light source to the digital micromirror device. The embodiment of the present invention will be specifically described with reference to an example.

As shown in FIG. 1, the image printing apparatus 1 according to the present invention substantially comprises an exposure printing processing section 2, a development processing section 3, and a drying processing section 4. Then, in the exposure printing processing unit 2, after the photographic paper 7 wound around the paper roller 6 in the paper magazine 5 is pulled out from the paper magazine 5, the photographic paper 7 is transported by a photographic paper transport mechanism having transport rollers 13 and the like. is adapted to be conveyed in the direction indicated by arrow a ₁ and arrow a _2. In addition, photographic paper 7
Is continuously moved in the transport direction at a constant speed by the photographic paper transport mechanism.

In the exposure printing unit 2, light (white light) emitted from a light source 8 (for example, a halogen lamp) is converted into R (red), G
After passing through a color filter (not shown) of either (green) or B (blue), the light becomes monochromatic light of R, G, or B, and is then arranged in a curved (non-linear) manner. The light is condensed by the optical fiber 22 and guided (incident) to the digital micromirror device 10. The color wheel 9 rotates intermittently at regular intervals according to the speed of the exposure processing, and sequentially switches the color filters through which light is to be transmitted. That is, the color of the monochromatic light is repeatedly switched in the order of R, G, and B at regular intervals. If the switching timing between the color wheel 9 and the color filter can be synchronized, the color wheel 9 may be switched by continuous rotation instead of intermittent rotation as described above.

The digital micromirror device 10
A reflected light, the image light L ₂ to the digital micromirror device 10 is accompanied by an image to be displayed, enlargement lens 11 stretched to the image light L ₃ by (printing lens), the stretched image light L ₃ Is irradiated on the photographic paper 7, and the photographic paper 7 is subjected to an exposure process. Thus, the image displayed by the digital micromirror device 10 is stretched by the enlargement lens 11 to form an image on the photographic paper 7, and the image is printed on the photographic paper 7. Note that such exposure processing or printing processing is performed by R, G
And B for the three monochromatic lights. That is, the R, G, and B images are superimposed and printed on the same exposure area of the printing paper 7.

The printing paper 7 on which the image has been printed as described above.
Is transported from the exposure printing processing section 2 to the developing processing section 3 by a photographic paper transport mechanism having transport rollers 13 and the like.
Then, the printing paper 7, while meandering developing unit developing solution tank 12 provided in the 3 to move generally in the arrow A ₃ direction is developed by the development processing solution. Thereafter, the printing paper 7 that has been developed is conveyed from the developing section 3 to the drying unit 4 by print paper transporting mechanism, is dried while moving the drying unit 4 in the arrow A ₄ direction, the image printing It is taken out of the device 1.

Hereinafter, a specific configuration and functions of the digital micromirror device 10, which is a reflection type digital image display device, will be described. As shown in FIG. 2A, the digital micromirror device 10 has a plate-like outer shape having a substantially rectangular spreading surface, and has a substantially rectangular micromirror portion in a frame portion 14 forming a housing in plan view. 15 are arranged. Then, as shown in FIG. 2B, a large number of micromirror units 15 (6 in FIG.
(Only the illustrated number of micromirrors 16 are arranged in a grid pattern). Substantially square in plan view, each of the micromirrors 16, the dimension H ₁ in the lateral direction (corresponding to the printing width direction) dimension D ₁ and vertical (corresponding to the printing paper conveying direction) are both generally 16μm approximately Are arranged so that the horizontal interval D ₂ and the vertical interval H ₂ are both approximately 1 μm. In the digital micromirror device 10 (SXGA standard), 1280 micromirrors 16 are arranged in the horizontal direction (1280 pixels) and 1024 micromirrors are arranged in the vertical direction (1024 pixels). Each micro mirror 16
Respectively correspond to one pixel.

As shown in FIG. 2C, each of the micro mirrors 16 (16a, 16b) has a structure in which a mirror plate 17 is supported by a yoke 18 via a support column 19. Although not shown in detail, the yoke 18 is rotatably connected to the substrate 20 via a connection structure. Here, when a memory element (not shown) arranged on the substrate 20 below each yoke 18 is energized, the state is shown, for example, on the left-side micro mirror 16a in FIG. 2C. Thus, the yoke 18 is rotated and inclined by the electrostatic action of the memory element until the left end of the yoke 18 contacts the substrate 20. In this state, the normal line S ₁ of the mirror plate 17 is inclined leftward by a predetermined angle θ with respect to the vertical line S ₀ (+ θ). That is,
The reflecting surface (spreading surface) of the mirror plate 17 is tilted to the left by θ (hereinafter, this state of the micromirror is “on”).
). At this time, the reflected light of the micromirror 16a is applied to the printing lens 11 and thus the photographic paper 7.

On the other hand, when the memory element is not energized, for example, the right micro mirror 16b shown in FIG.
As shown in FIG. 2, the yoke 18 is rotated and inclined by the electrostatic action of the memory element until the right end thereof contacts the substrate 20. In this state, the normal S ₂ of the mirror plate 17 is inclined rightward by a predetermined angle θ with respect to the vertical line S ₀ (−θ). That is, the reflection surface of the mirror plate 17 is inclined rightward by θ (hereinafter, this state of the micromirror is referred to as “off”). At this time, the reflected light of the micromirror 16b is not irradiated on the printing lens 11 (the photographic paper 7), but is absorbed by a light absorbing plate (not shown).

Thus, the digital micromirror device 1
0 switches (sets) the on / off state of each micromirror 16 based on digital image data corresponding to an arbitrary image so as to correspond to the image. That is, the micromirror unit 15 of the digital micromirror device 10 displays an image in which each micromirror 16 has one pixel (one pixel). Here, the time required to switch on / off each micromirror 16 is about 10 microseconds.

Hereinafter, a specific configuration and functions of an exposure system from the light source 8 to the photographic paper 7 via the digital micromirror device 10 and the like will be described. As shown in FIG. 3A, in the exposure system of the image printing apparatus 1 according to the present invention, white light emitted from the light source 8 is converted into R, G or B color filters 9 by R, G or B color filters. Alternatively, it is B monochromatic light. The monochromatic light is condensed by the optical fiber 22 and enters (irradiates) the digital micromirror device 10.
Is done. Here, the light source 8 and the color wheel 9 are arranged in the vicinity of the digital micromirror device 10 in order to make the image printing apparatus 1 compact, so that the optical fiber 22 is bent in a substantially U shape. . The optical fiber 22 is located near the digital micromirror device 10.
Original light is emitted toward the digital micromirror device 10 in a straight line. The optical axis of the linear portion of the optical fiber 22 is M _2.

The digital micromirror device 10
A reflected light, the image light L ₂ to the digital micromirror device 10 is accompanied by an image to be displayed is stretched by enlargement lens 11 is irradiated to the printing paper 7 becomes image light L _3. Here, the image light L ₂ and the expanded image light L ₃ are connected to the digital micromirror device 10.
From the photographic paper 7 to the photographic paper 7. That is, the image light L ₂ and the image light L _3, which stretched has an optical axis M ₁ common straight line.

Here, the optical axis M ₁ of the image light L ₂ or the elongated image light L ₃ and the optical axis M ₂ of the linear portion of the optical fiber 22 are determined according to the reflection characteristics of the digital micromirror device 10. , At a predetermined angle α (for example, 20 °).

Thus, in the image printing apparatus 1 having such an exposure system, the shape of the optical fiber 22, that is, the optical path of the original light from the light source 8 (color wheel 9) to the digital micromirror device 10 can be formed in any shape. By setting the optical path to an appropriate shape, various parts such as the light source 8, the color wheel 9, the digital micromirror device 10, and the enlargement lens 11 can be laid out with a large degree of freedom. The size of the device can be reduced. In addition, for example, a conventional image printing apparatus as shown in FIG. 3 (b) requires a plurality of light sources, such as a first condenser lens 30, a second condenser lens 31, and a condenser rod 32, which are necessary for condensing the original light. Since optical parts are not required in the image printing apparatus 1 according to the present invention, the structure of the image printing apparatus 1 is simplified.

Further, since the optical path length between the light source 8 and the digital micromirror device 10 can be shortened,
Light use efficiency is improved. That is, for example, FIG.
As shown in (b), when the condensing lenses 30 and 31 are used, a certain distance is required to condense the original light. However, when the optical fiber 22 is used,
Since the original light can be incident on the digital micromirror device 10 at the shortest distance, there are advantages that light can be used efficiently and that the image printing apparatus 1 can be downsized.

In the image printing apparatus 1 according to the present invention, the original light is guided from the light source 8 (color wheel 9) to the digital micromirror device 10 via the optical fiber 22. The light is incident (irradiated) on the digital micromirror device 10 with almost no attenuation. Therefore, the light use efficiency is further improved. In the case of the conventional image printing apparatus as shown in FIG. 3B, since the original light is condensed by using the condensing lenses 30 and 31, a large amount of light is scattered from the optical path. The usage efficiency becomes poor.

In the image printing apparatus 1 according to this embodiment, the digital micromirror device 10
Although the optical fiber 22 is used as the light guiding means to the
The light guiding means is not limited to an optical fiber, but may be any such as a mirror tunnel as long as it can minimize the loss of light and bend the optical path into an arbitrary shape. A similar effect can be obtained by changing the optical path using a mirror or a prism capable of forcibly changing the light path.

In the image printing apparatus 1 according to this embodiment, the digital micromirror device 10 is used as a reflection type image display device. However, the image display device is not limited to the digital micromirror device. For example, any image display device, such as a reflective LCD, which can form an image by reflecting light from a light source may be used.

[Brief description of the drawings]

FIG. 1 is an elevational view showing a schematic configuration of an image printing apparatus according to the present invention.

FIG. 2A is a plan view of a micromirror device, and FIG. 2B is an enlarged plan view of a micromirror constituting the micromirror device shown in FIG.
(C) is an elevation view of the micro mirror.

3A is a side view of an exposure system of the image printing apparatus shown in FIG. 1, and FIG. 3B is a side view of an exposure system of the image printing apparatus having a conventional exposure mechanism.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Image printing apparatus, 2 ... Exposure printing processing part, 3 ... Development processing part, 4 ... Drying processing part, 5 ... Paper magazine, 6 ... Paper roller, 7 ... Printing paper, 8 ... Light source, 9 ... Color foil, 10 ... Digital micromirror device, 11 ... Elongating lens, 12 ... Developing solution tank, 13 ... Conveying roller, 14 ... Frame part, 15 ... Micromirror part, 16 ... Micromirror, 16a ... Micromirror, 16b ... Micromirror, 17 ... mirror plate, 18 ... yoke, 19
.., A support, 20 ... a substrate, 22 ... an optical fiber, 30 ... a first condenser lens, 31 ... a second condenser lens, 32 ... a condenser rod.

Claims (6)

[Claims] A reflection type image display device for displaying an image by reflecting light emitted from a light source is provided, and the image display device displays light with an image composed of a large number of pixels on a photosensitive material. In a printing apparatus adapted to irradiate and expose the photosensitive material to print the image on the photosensitive material, the light emitted from the light source is condensed, and the light is condensed through a non-linear optical path. A printing device, comprising: a light guide means for guiding the image display device. 2. The printing apparatus according to claim 1, wherein said light guide means forms a non-linear optical path by an optical fiber. 3. The printing apparatus according to claim 1, wherein the light guide means forms a non-linear optical path by a prism. 4. The printing apparatus according to claim 1, wherein the exposure processing is performed while moving the photosensitive material. 5. The printing apparatus according to claim 1, wherein the exposure processing is performed with the photosensitive material stopped. 6. The image display device includes a plurality of micromirrors each of which can switch a reflection direction, and displays an image by switching a reflection direction of each micromirror so as to correspond to the image. The printing device according to claim 1, wherein the printing device is a digital micromirror device.