JPH04344631A - Shuttle type exposing device - Google Patents

Abstract

PURPOSE:To provide a shuttle type exposing device capable of making the resolution of an outputted image higher than the resolution of an optical shutter panel which is used in an exposing device. CONSTITUTION:The optical shutter panel which has an aperture part equal to or under the area of the single picture element of the optical shutter panel corresponding to each picture element shutter 19 and which is provided with a light shielding mask is intermittently moved in a direction perpendicular to the advancing direction of a photosensitive medium 3 at the pitch, which is obtained by integrally dividing the pitch of the picture element of the optical shutter panel, by a driving means such as a step motor, etc. A photosensitive recording medium 3 is intermittently fed just under the optical shutter panel at the pitch, which is obtained by integrally dividing the pitch of the picture element of the optical shutter panel, by the driving means 9 such as the step motor, etc. The photosensitive medium 3 is exposed by transmitting light from a back light and forming image light on the photosensitive medium 3 by on/off controlling each picture element shutter of the optical shutter panel in accordance with an inputted signal at the time of stopping the intermittent movement.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure section of, for example, an optical printer or a digital copying machine.

0002

2. Description of the Related Art Conventionally, an exposure device consisting of an optical shutter panel composed of a plurality of pixel shutters and used in an exposure unit of an optical printer or a digital copying machine, etc., is disclosed, for example, in Japanese Patent Application Laid-Open No. 2-112964. There is an exposure device as shown in FIG. 3, and as shown in FIG. 3, the exposure means 8 is a means for generating image light corresponding to a document or an input signal, and includes a transmissive liquid crystal shutter 2,
It includes a backlight 1 such as a halogen lamp disposed above it, and a lens 5 that collects light transmitted through a liquid crystal shutter 2 and forms an image on a photosensitive medium 3, which will be described later.

[0003] This liquid crystal shutter 2, for example,
By turning on and off the liquid crystal as shown in the figure in response to the letters BC, light from the backlight 1 is transmitted and image light is created on the photosensitive medium 3.

[0004] A photosensitive medium 3 such as photosensitive paper or a photosensitive drum is disposed below the lens 5 of the exposure means 8, on which an image is formed by exposure. As the photosensitive medium 3, those shown in, for example, Japanese Patent Laid-Open No. 58-230325 and Japanese Patent Laid-Open No. 58-88739 are used.

The exposure area 6 virtually shows the image positional relationship on the photosensitive medium 3 corresponding to each pixel of the liquid crystal shutter 2.

The transporting means 7 is a means such as a motor for transporting the photosensitive medium 3 at a predetermined speed, and the control means 4 is a means for transporting the photosensitive medium 3 at a speed having a predetermined relationship with the transporting speed of the photosensitive medium 3, for example, synchronously. This is means for moving the image of the exposure means 2 at a high speed.

That is, when the liquid crystal shutter 2 is turned on properly,
The image light is turned off and the image light is moved, and is realized using a microcomputer or the like.

Next, to explain the operation of the above conventional example, the transporting means 7 transports the photosensitive medium 3 at a predetermined speed in the direction shown by arrow A in FIG.

The backlight 1 emits light toward the liquid crystal shutter 2, and the control means 4 turns on each pixel of the liquid crystal shutter 2 corresponding to ABC to generate image light of ABC.

Furthermore, the control means 4 turns the pixels on and off to move the ABC images in the direction of arrow B in synchronization with the moving speed of the photosensitive recording medium 3.

As a result, even if the photosensitive recording medium 3 moves, the ABC image light imaged on the photosensitive recording medium 3 via the lens 5 moves in the same direction and at the same speed. .

[0012] Therefore, since the ABC image light always moves while irradiating the same part of the photosensitive recording medium 3,
While moving from one edge of the exposure area 6 to the other edge, a sufficient exposure time necessary for forming a latent image can be secured.

Furthermore, by adjusting the number of pixels turned on in the direction of arrow B of the liquid crystal shutter 2, various gradations can be realized.

Furthermore, in order to obtain biased magnification images for enlargement and reduction, the optical path length is changed at each ratio, and the relative speed relationship between the transport speed of the photosensitive medium and the image movement speed of the exposure means is adjusted accordingly. This can be achieved by making changes.

[0015]

However, in such an exposure apparatus, the resolution of the image on the photosensitive recording medium is determined by the resolution of the pixel shutter of the optical shutter panel, and therefore the resolution of the output image is determined by the exposure It was difficult to increase the resolution beyond the optical shutter panel used in the device.

[0016] Furthermore, in order to obtain a high resolution output image,
Increasing the resolution by reducing the size of each pixel in an optical shutter panel, which is composed of multiple lines of pixel shutters, was disadvantageous in terms of manufacturing costs as it was reflected in the cost. It is technically difficult to achieve the high resolution achieved by other well-known exposure devices, such as laser scanners.

The present invention has been made in order to solve the above-mentioned problems, and uses an optical shutter panel that is low in cost and has a resolution that can be achieved with the conventional technology, and increases the resolution of an output image by adjusting the exposure. Higher resolution than the optical shutter panel used in the device, i.e. higher resolution,
The objective is to obtain high-quality output images at low cost.

[0018]

[Means for Solving the Problems] In order to achieve this object, the shuttle-type exposure apparatus of the present invention provides a light-shielding mask having an opening corresponding to each pixel shutter and having an opening smaller than or equal to the area of a single pixel of the optical shutter panel. means for intermittently moving the optical shutter panel in a direction perpendicular to the traveling direction of the photosensitive recording medium at a pitch that divides the pixel pitch of the optical shutter panel by an integer; It is provided with a means for intermittently moving a distance that divides the pixel pitch of the panel by an integer, and an illumination means such as a halogen lamp, which transmits light through the shutter panel and exposes the photosensitive recording medium.

[0019]

[Operation] In the present invention having the above configuration, the light-shielding mask has an aperture set approximately at a size obtained by dividing the pixel pitch of the optical shutter panel by an integer, and corresponds to each pixel of the optical shutter panel. It is fixed on the optical shutter panel so as to narrow the light-transmitting area of each pixel.

The optical shutter panel intermittently moves back and forth in a direction perpendicular to the direction of travel of the photosensitive medium at a pitch equal to the above-mentioned integer division of the pixel pitch of the optical shutter panel.

Further, the photosensitive medium is arranged directly under the optical shutter panel at a pitch equal to the above-mentioned integral number division of the pixel pitch in the same direction as the traveling direction of the photosensitive medium of the optical shutter panel, for example, by a stepping motor or the like. It is sent intermittently by means.

In order to expose the photosensitive medium, each pixel shutter of the optical shutter panel is turned on and off according to the input image signal at the stop of each intermittent movement, and an illumination means disposed above the optical shutter panel. For example, it is exposed to transmitted light from a halogen lamp or the like.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment embodying the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an embodiment of an image recording apparatus using a shuttle type exposure apparatus according to the present invention, and FIG. 2 shows a control means for controlling exposure of the image recording apparatus. FIG. 4 is a block diagram showing the positional relationship between each pixel shutter of the optical shutter panel and the light-shielding mask opening.

Referring to FIG. 1, the exposure means 8 of this embodiment is slidably mounted on guide bars 10 and 11 extending in a direction perpendicular to the traveling direction of the photosensitive medium 3, and is constructed of, for example, a step motor. The head moving means 9 intermittently moves the photosensitive medium 3 in a direction perpendicular to the traveling direction of the photosensitive medium 3 via a pulley 12 and a wire rope 13 partially fixed to the exposure means 8 .

The exposure means 8 of this embodiment is composed of a backlight 1, a transmissive liquid crystal shutter 2, and a reflector 18, and the transmissive liquid crystal shutter 2 is provided with an opening shown in FIG. 4 on its entire surface. A light-shielding mask is fixed, and each pixel shutter 1 of the transmissive liquid crystal shutter 2 is opened in response to an input signal each time the exposure means 8 moves intermittently.
9 turns on and off to transmit light from the backlight 1 and create image light on the photosensitive medium 3.

The photosensitive medium 3 is attached to the photosensitive medium supply roll 1
4 , is guided by guide rollers 16 and 17 so as to be located directly below the optical shutter panel 2 , and is wound onto the photosensitive medium take-up roll 15 .

The photosensitive medium transporting means 7 is composed of, for example, a stepping motor, and the photosensitive medium winding roll 1
5, the photosensitive medium 3 is wound intermittently during exposure, and is wound at a certain constant speed during development.

As described above, the transfer sheet 20 shown in Japanese Patent Application Laid-Open No. 58-230325 and Japanese Patent Application Laid-Open No. 58-88739 is used, and the separating roller 21 and the guide roller 22 are used for the transfer sheet 20 when outputting an image. Transfer sheet 20
is conveyed to the developing roller 23 one by one.

The developing roller 23 brings the photosensitive medium 3 and the transfer sheet 20 together and applies a pressing force to transfer and develop the latent image on the photosensitive medium 3 onto the transfer sheet 20.

The transfer sheet 25 on which the image on the photosensitive medium 3 has been transferred is conveyed to a heat fixing roller 24 by a well-known paper conveyance means (not shown), and after the image is completely fixed, it is transferred from the image recording apparatus to an external device. is discharged to.

The heat fixing roller 24 is composed of, for example, an aluminum pipe equipped with a halogen lamp 26 inside and a rubber roller, and uses its heat to promote color development of the image on the transfer sheet and perform fixation.

Next, with reference to FIG. 2, a block diagram in which the control means 4 of the exposure section is realized using a microcomputer will be explained.

Image information sent from the input means 31 is converted by the input control circuit 32 into data that can be calculated by the central processing unit 37.

The central processing unit 37 includes a read-only memory (ROM) 38 storing programs for controlling as will be described later, and a read/write memory (R).
AM) 33 to convert the data into on/off control of each pixel shutter 19 of the liquid crystal shutter 2, intermittent movement control of the head transport means 9, movement speed of the photosensitive medium 3, etc. The liquid crystal shutter 2, the transfer means 7, and the transfer means 9 are driven via 34, 35, and 36.

Next, the difference between the operation of the exposure section of the image recording apparatus constructed as described above and the conventional example will be explained.

Referring to FIG. 4, the transmissive liquid crystal shutter 2 of this embodiment has a light shielding mask fixed to its entire surface, as described above.

The opening size of the light-shielding mask is, for example, a size a that is approximately 1/4 of the pitch 4a of the pixel shutter 19 in the direction perpendicular to the traveling direction of the photosensitive medium 3 (X-axis direction).
In the direction parallel to the traveling direction of the photosensitive medium 3 (Y-axis direction), approximately 1/4 of the pitch 4b of the pixel shutter 19
The size of b is b.

In this embodiment, the dimensions of the light-shielding mask opening are approximately 1/4 of the pixel shutter pitch in both the X-axis direction and the Y-axis direction, but the light-shielding mask opening dimensions are each an integer of the pixel shutter pitch. If it is one-fold, it can be determined depending on the desired resolution of the output image, and the divisions in the X-axis direction and the Y-axis direction do not need to be the same.

The head transport means 9, which is composed of a step motor or the like, for example, intermittently transports the exposure means 8 by means of the control means 4, and the transport pitch at this time is precisely the dimension a. Further, while the exposure means 8 is moved three steps in the positive direction of the X-axis, each pixel shutter 19 of the transmission type optical shutter 2 is controlled to be turned on and off four times in accordance with the input image information. Therefore, in FIG. 4, the first pixel, the second pixel, the third pixel, etc. are exposed to light four times on the photosensitive medium 3, and the first pixel, the second pixel, and the second pixel are exposed four times.
Connected to pixels, third and second pixels, etc. That is, the input image information is continuous in the X-axis direction.

Next, the photosensitive medium transporting means 7, which is constituted by a step motor or the like, moves the photosensitive medium 3 accurately b in the positive direction of the Y axis shown in FIG.
The image is moved by one step with a dimension of , and the four exposures in the X-axis direction are repeated again.

As described above, the input image information is transferred three times in the Y-axis direction, and is exposed four times in the X-axis direction for each step, for a total of 16 exposures.
It is also connected in the axial direction.

Furthermore, in the 17th exposure, the portion of the photosensitive medium 3 corresponding to the 1st pixel of the 1st exposure has advanced to the position of the 2nd 1st pixel in the light-shielding mask opening.

From then on, the positional relationship is the same as in the conventional example, except that the number of divisions in both the X-axis, Y-axis, and both directions is increased, and the image light based on the input image information is transmitted as the photosensitive medium 3 moves. As it moves, it also moves in the same direction.

Therefore, different image light always illuminates the same part of the photosensitive medium 3, and the photosensitive medium 3 moves from one edge of the exposure area of the liquid crystal shutter 2 to the other edge. In the meantime, the exposure time necessary for forming a latent image is sufficiently secured, and various gradations can also be realized in the same manner as in the conventional example.

That is, in this embodiment, an output image resolution four times that of the conventional example can be achieved in the X-axis direction using a conventional optical shutter, and in the direction parallel to the traveling direction of the photosensitive medium 3, That is, it is possible to achieve an output image resolution four times that of the conventional example also in the Y-axis direction.

The photosensitive medium 3, which has been exposed through the above operations, is wound up at a certain constant speed as described above, and at the same time, the latent image on the photosensitive medium 3 is transferred to the transfer sheet 20 by the developing roller 23. After being transferred and developed, the output image is discharged from the image recording apparatus to the outside through the above-described steps.

As is clear from the detailed description above, according to the shuttle type exposure apparatus of this embodiment, each pixel shutter 19 has an aperture smaller than the area of a single pixel in the conventional transmissive liquid crystal shutter 2. Equipped with a light-blocking mask that corresponds to
The exposure means 8 is moved in a direction perpendicular to the traveling direction of the photosensitive medium 3.
By intermittently moving the pixel pitch of the optical shutter panel 2 at a pitch that divides the pixel pitch by an integer, and by moving the photosensitive recording medium intermittently at a distance that divides the pitch of the pixel shutter 19 of the optical shutter panel 2 by an integer, the resolution of the output image can be increased. This allows the resolution to be higher than that of the optical shutter panel 2.

It should be noted that the present invention is not limited to the embodiments described in detail above, and various modifications can be made without departing from the spirit thereof.

For example, in this embodiment shown in FIG. 1, the conventional structure without the imaging lens 5 is used, that is, the method of directly exposing the photosensitive medium 3 with the image light on the optical shutter panel,
As explained in , in order to obtain a biased image such as enlargement or reduction, as in the conventional example, the exposure means 8 is equipped with an imaging lens 5 and the image light is formed on the photosensitive medium 3. do it.

Further, in this embodiment, a transmissive liquid crystal shutter was used as the exposure means, but a reflective liquid crystal shutter with multiple lines may also be used, and a PLZ shutter with multiple lines may also be used.
An optical shutter panel using a T element may also be used.

[0052]

[Effects of the Invention] As is clear from the above explanation, according to the shuttle-type exposure apparatus of the present invention, an aperture smaller than the area of a single pixel is formed in a conventional optical shutter panel, corresponding to each pixel shutter. The optical shutter panel is intermittently moved in a direction perpendicular to the traveling direction of the photosensitive recording medium at a pitch that divides the pixel pitch of the optical shutter panel by an integer, and the photosensitive recording medium is moved between the pixels of the optical shutter panel. By intermittently moving the pitch at a distance that divides the pitch by an integer, the resolution of the output image can be increased to a level higher than that of the optical shutter panel.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of an image recording apparatus equipped with a shuttle type exposure device of the present invention.

FIG. 2 is a block diagram of a control means that controls exposure of the image recording apparatus.

FIG. 3 is a perspective view showing a conventional exposure apparatus.

FIG. 4 is a diagram showing the positional relationship between a pixel shutter and a light-shielding mask opening.

[Explanation of symbols]

1 Backlight 2 Transmissive liquid crystal optical shutter 3 Photosensitive recording medium 4 Control means 7 Photosensitive medium transport means 8 Exposure means 9 Head transfer means 10 Guide bar 11 Guide bar 12 Pulley 13 Wire rope 14 Photosensitive media supply roll 15 Photosensitive medium take-up roll 16 Guide roller 17 Guide roller 19 pixel shutter

Claims (1)

[Claims] 1. An image recording device that outputs an image using a photosensitive recording medium, comprising a light-shielding mask having an opening smaller than the area of a single pixel of an optical shutter panel corresponding to each pixel shutter, An optical shutter panel that moves intermittently at a distance that divides the pixel shutter pitch of the optical shutter panel by an integer in a direction perpendicular to the direction of travel of the medium, and a pixel shutter pitch of the optical shutter panel that moves in a direction parallel to the direction of travel of the photosensitive recording medium. The distance to divide by an integer,
A shuttle type exposure device equipped with means for intermittently moving a photosensitive recording medium.