JPH0818745A - Exposure optical system and printer using the optical system - Google Patents

Abstract

PURPOSE:To simultaneously form printed pictures for a positive image and a negative image from one picture signal by distributing an optical beam made incident upon a light deflecting element to a 1st optical path for forming an image on a photosensitive body and a 2nd optical path for deflecting an optical beam unnecessary for image formation from the photosensitive body. CONSTITUTION:The light deflecting element 4 driven by an image signal sets up the angle of a line-like fine reflection surface 41. to 1st and 2nd angles in accordance with the image signal. A luminous flux outgoing from a rod-like light source 1 including a cylindrical mirror 2 is almost uniformly applied to the surface of the reflection surface 4a1 through a defractive index distribution type lens array 3. First (2nd) image light generated by reflected light set up to the 1st (2nd) angle is projected on a photosensitive drum 6a (6b) by a projection lens 5a (5b). A positive image and a negative image are simultaneously formed on the 1st and 2nd photosensitive bodies by the 1st and 2nd projecting means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure optical system for generating blinking light (image light) according to an image signal and exposing it on a photosensitive surface. In particular, a plurality of deflectable minute reflecting surfaces are linear. The present invention relates to an exposure optical system that generates image light by controlling a light deflection element provided in the image pickup device according to an image signal. Furthermore, it relates to a printer using the exposure optical system.

[0002]

2. Description of the Related Art Conventionally, in a laser beam printer or the like,
Blinking light (image light) corresponding to an image signal is generated, and the generated blinking light is exposed (image exposure) on a photosensitive surface to obtain a print image of a positive image or a negative image.

As exposure optical systems for generating image light according to the image signals, many exposure optical systems have been proposed so far, and among them, light deflection in which a plurality of deflectable minute reflecting surfaces are provided in a line shape. Regarding an exposure optical system using an element, Japanese Patent Laid-Open No. 61-116324, Japanese Patent Laid-Open No. 61-129627, Japanese Patent Laid-Open No. 58-10714, Japanese Patent Publication No. 3-78622, and Optical No. 20
Those described in Volume No. 10 (October 1991) and the like have been proposed.

The light deflecting means described in each of the above publications and publications is provided with a reflector having a plurality of deflectable minute reflecting surfaces on a substrate, and a voltage is applied to the substrate according to an image signal. However, the light beam incident on the reflector is deflected by changing the angle of each minute reflecting surface. What is described in the above Japanese Patent Publication No. 3-78622 will be described below.

The light deflecting means described in Japanese Patent Publication No. 3-78622 is a linear array of deflectable finger-like reflectors on a substrate which can be inserted into a light beam path, and which is responsive to an image signal. By applying a voltage to the substrate to bend each finger-shaped reflector, the incident light beam is deflected according to the image signal. In the light deflecting means described in this publication, a reflector having a voltage applied to both ends of a plurality of linearly arranged reflectors bends and impinges a light beam that is incident in the original reflection direction ( (Direction to the photoconductor)
Image light corresponding to the image signal is generated by reflecting the light in a different direction.

In a printer using an exposure optical system having such a light deflecting means, the image light generated by the light deflecting means is exposed on the photoconductor to form a latent image of a positive image or a negative image. The formed latent image is output as a print image.

[0007]

In the conventional exposure optical system in which the light deflecting means as described above is used, the light beam incident on the light deflecting means forms an image on the photosensitive member by the light deflecting means. Image light is generated by being divided into a first optical path and a second optical path that diverts a light beam not necessary for image formation from the photoconductor, and the light beam distributed to the first optical path is formed on the photoconductor. Projected on. As described above, in the exposure optical system that uses only the light beam distributed to the first optical path as the image light, only one of the positive image and the negative image can be generated from one image signal. It was inefficient.

Further, in a printer using an exposure optical system that uses only the light beam distributed to the above-mentioned first optical path as image light, both positive and negative images are printed from one image signal. Therefore, if you want both positive and negative images for design purposes, use two printers for positive and negative images, or set the internal printer. Each time, the image is printed by changing it.
As described above, the printer using the above-described exposure optical system has been troublesome and inefficient when printing both a positive image and a negative image.

An object of the present invention is to provide an exposure optical system capable of simultaneously forming a positive image and a negative image. Furthermore, it is to provide a printer using the exposure optical system.

[0010]

The exposure optical system of the present invention comprises:
A light source, a plurality of deflectable micro-reflecting surfaces provided in a line, and a means for irradiating the plurality of micro-reflecting surfaces with a light beam emitted from the light source substantially uniformly, In the exposure optical system in which the angle of each of the minute reflection surfaces is set to first and second angles according to an image signal, and the reflected light generates image light, the minute reflection surface set to the first angle. A first projection means for projecting a first image light generated by the reflected light of the second image light, and a second projection light for projecting a second image light generated by the reflected light of the minute reflection surface set at the second angle. And two projection means.

In the exposure optical system, the first image light generated by the reflected light of the minute reflecting surface set to the first angle and the reflected light of the minute reflecting surface set to the second angle. The second image light generated by is image light generated from one image signal, and is characterized by having a positive relationship and a negative relationship, respectively.

Further, the printer of the present invention uses the exposure optical system having the above respective characteristics, and has first and second photoconductors to which an electrophotographic process is applied,
Two different image lights generated by the exposure optical system are applied to the first and second photoconductors to form latent images, and latent images formed on the first and second photoconductors, respectively. Is output as a print image. [Detailed Description of the Invention]

[0013]

In the conventional exposure optical system, the light beam incident on the light deflecting means is converted into a first light path for forming an image on the photosensitive member by the light deflecting means and a light beam not necessary for image formation. Distribute to the second optical path deflected from the photoconductor,
Since only the image light generated by the light beam distributed to the first optical path is projected on the photoconductor, only one of the positive image and the negative image can be formed from one image signal. I can't.

On the other hand, in the exposure optical system of the present invention configured as described above, the minute reflecting surface of the light deflecting means is the first.
The image light generated when the angle is set to is projected onto the first photoconductor by the first projecting means, and the image light generated when the minute reflection surface is set to the second angle is generated by the second projecting means. Is projected onto the second photoconductor. As described above, according to the present invention, the first projection unit projects the image light by the first projection unit.
And the second optical path on which the image light is projected by the second projection means are projected onto the first and second photoconductors, respectively, so that a positive image is formed on the first optical path. Alternatively, if the image light of any one of the negative images is generated, an inverted version of the image light generated in the first optical path is generated in the second optical path.
It is possible to form two images, a positive image and a negative image, simultaneously from one image signal. Further, in the printer using the exposure optical system of the present invention, the first and second photoconductors are provided, and the image light of the positive image and the negative image is formed by the first and second projection means of the exposure optical system. Are projected onto the first and second photoconductors, respectively, a latent image of a positive image and a negative image can be formed on each photoconductor, and a positive image and a negative image can be printed from one image signal. An image can be formed.

[0015]

Embodiments of the present invention will now be described with reference to the drawings.

FIG. 1 is a schematic configuration diagram of an exposure optical system according to a first embodiment of the present invention, and FIG. 2 is a perspective view showing an arrangement relationship of each component of the exposure optical system shown in FIG.

The exposure optical system of this embodiment generates image light of a positive image and a negative image from one image signal, and projects the generated image light on the first and second photosensitive drums, respectively. is there. The exposure optical system includes a rod-shaped light source 1 provided with a cylindrical mirror 2, and a refractive index distribution type lens sequentially arranged in the traveling direction of the light beam emitted from the rod-shaped light source 1 or the light beam reflected by the cylindrical mirror 2. Array 3, light deflection element 4, and light deflection element 4
From the projection lens 5a and the photoconductor drum 6a, which are sequentially arranged in the traveling direction of the light beam reflected in the first direction, and in the traveling direction of the light beam reflected from the light deflection element 4 in the second direction. The projection lens 5b and the photoconductor drum 6b are provided.

In the above-mentioned exposure optical system, the cylindrical mirror 2 returns the light flux escaping backward of the light flux emitted from the rod-shaped light source 1 to the light source again, and is arranged so that the rod-shaped light source 1 comes to the focal position. It is set up. The gradient index lens array 3 is provided so as to face the rod-shaped light source 1, and divides the light beam emitted from the rod-shaped light source 1 or the light beam reflected by the cylindrical mirror 2 into a plurality of light beams corresponding to pixels. The light deflection element 4 is illuminated linearly. In the present embodiment, the cylindrical mirror 2 and the gradient index lens array 3 allow the luminous flux emitted from the rod-shaped light source 1 to be efficiently and substantially evenly deflected.
Illuminated on.

The light deflection element 4 has a plurality of minute reflection surfaces 4a _i . The light deflection element 4 is provided so as to face the gradient index lens array 3, and each light flux emitted from the gradient index lens array 3 is incident on each of the minute reflection surfaces 4a _i. ing.

Each of the light deflecting elements 4 has a minute reflecting surface 4a.
_i Connected to the optical deflection drive circuit 7 for controlling the reflection angle of
The optical deflection driving circuit 7 includes an image signal generating circuit.
8 are connected. With this optical deflection drive circuit 7,
Micro reflective surface 4a_i The reflected angle of the reflected light is the projection lens 6
The first angle of incidence on a (here, the minute reflection surface 4a _i 
(When no voltage is applied to the
Second angle of incidence on the lens 6b (here, optical deflection drive
Minute reflection surface 4a by the circuit 7_i Voltage is applied to the
State). In addition, as the light deflection element 4,
The above-mentioned Japanese Patent Laid-Open Nos. 61-116324 and 61
No. 129627, JP-A No. 58-10714
Report, Japanese Examined Patent Publication No. 3-78622, and Optics Volume 20
As described in No. 10 (October 1991)
Used.

In the exposure optical system of the present embodiment configured as described above, the light deflection drive circuit 7 causes the minute reflection surfaces 4a of the light deflection element 4 to operate based on the image signal input from the image signal generation circuit 8. By controlling the reflection angle of _i and distributing each light beam by the light deflection element 4, for example, the photoconductor 6
A positive image is formed on a and a negative image is formed on the photoconductor 6b. That is, in this embodiment, a negative image is formed by irradiating the photoconductor 6b with a light beam deflected to form the unexposed portion of the photoconductor 6a on which a positive image is formed.

In the printer using the above-mentioned exposure optical system, the photoconductor drums 6a and 6b are both subjected to the electrophotographic process, and the photoconductors 6a and 6b are
The latent images formed on the respective 6b are subjected to processings such as development, transfer and fixing, and are transferred to paper or the like.

Next, the optical operation of the above-mentioned exposure optical system will be described.

The luminous flux emitted from the rod-shaped light source 1 is incident on the gradient index lens array 3 directly or after being reflected by the cylindrical mirror 2. Gradient Index Lens Array 3
The light flux incident on the light beam is divided into a plurality of light fluxes and is incident on each of the minute reflection surfaces 4a _i of the light deflection element 4. At this time, the respective angles of the minute reflection surfaces 4a _i of the light deflection element 4 are set to the first or second angle by the light deflection drive circuit 7 according to the image signal input from the image signal generation circuit 8. ing.

When each light flux emitted from the gradient index lens array 3 is incident on each micro-reflecting surface 4a _i of the light deflecting element 4, the incident light flux is incident on the portion set to the first angle. The incident light flux is reflected toward the projection lens 5a, and the light flux incident on the portion set at the second angle is reflected toward the projection lens 5b.

The light beam reflected by the minute reflection surface set to the first angle and incident on the projection lens 5a is projected onto the photoconductor drum 6a by the projection lens 5a, and the exposed portion is exposed on the photoconductor drum 6a. A one-line positive image composed of the unexposed portion is formed. Similarly, the light flux reflected by the minute reflection surface set to the second angle and incident on the projection lens 5b is projected onto the photoconductor drum 6b by the projection lens 5b, and is exposed on the photoconductor drum 6b. A one-line negative image composed of the unexposed portion is formed.

Therefore, in the printer using this exposure optical system, the angle of each micro-reflecting surface 4a _i set by the light deflection driving circuit 7 is controlled in association with the rotation of the photosensitive drum 6a to generate an image signal. When signals are generated in time series by the circuit 8, two-dimensional latent images of a positive image and a negative image are simultaneously formed on the photoconductor drums 6a and 6b. Then, in this way, the photosensitive drum 6
The latent images of the positive image and the negative image formed on a and 6b are subjected to respective processings of development, transfer and fixing, and transferred to paper or the like.

Next, another embodiment of the present invention will be described.

FIG. 3 is a schematic diagram of the exposure optical system of the second embodiment of the present invention.

The exposure optical system of the present embodiment is one in which the photosensitive drums 6a and 6b of the exposure optical system of the first embodiment described above are easily arranged and mirrors 9a and 9b are provided. The exposure optical system has the same configuration as that of the exposure optical system of the first embodiment except that the positions of the photosensitive drums 6a and 6b are changed. The same components as those of the exposure optical system of the first embodiment are designated by the same reference numerals.

In the exposure optical system shown in FIG. 3, the light deflection element 4 is used.
From the mirror 9 in the traveling direction of the light beam reflected in the first direction.
a is provided, and a mirror 9b is provided in the traveling direction of the light beam reflected from the light deflection element 4 in the second direction. The projection lens 5a and the photosensitive drum 6a are sequentially arranged in the traveling direction of the light flux reflected from the mirror 9a, and the projection lens 5b and the photosensitive drum 6b are sequentially arranged in the traveling direction of the light flux reflected from the mirror 9b. It is arranged. It should be noted that the first and second directions reflected by the light deflection element 4 referred to here are with respect to the optical axis of the optical system constituted by the rod-shaped light source 1, the cylindrical mirror 2, and the gradient index lens array 3. , Are directions that are reflected at a predetermined angle in mutually opposite directions.

In the exposure optical system configured as described above,
An optical system including a rod-shaped light source 1, a cylindrical mirror 2, a gradient index lens array 3 and a light deflecting element 4 is provided in the central portion, and a light beam incident on the light deflecting element 4 is directed to the optical axis of the optical system. And reflected at a predetermined angle in opposite directions. Then, the reflected light beam is reflected by the mirror 9
It is reflected by a and 9b, and projected on the photoconductor drums 6a and 6b by the projection lenses 5a and 5b.

As described above, in the exposure optical system of this embodiment, the optical system including the rod-shaped light source 1, the cylindrical mirror 2, the gradient index lens array 3 and the light deflection element 4 is provided in the central portion, and each photosensitizer is exposed. Since the body drums 6a and 6b are provided on the left and right of the optical system via the mirrors 9a and 9b and the projection lenses 5a and 5b, they are more compact than the printer using the exposure optical system of the first embodiment. Can be something.

In the exposure optical systems of the first and second embodiments described above, black-and-white images are printed. However, the exposure optical system of the present invention uses four colors of cyan, magenta, yellow and black. It can also be applied to a printer that prints in color, in which case a positive color image and a negative color image can be obtained at the same time if the process of forming a color print of four colors of cyan, magenta, yellow and black is performed once. .

In the printer using the exposure optical system of the present invention, if one of the photosensitive drums is used for positive development and the other photosensitive drum is used for negative development, it is used once. With this printing, it is possible to obtain two positive images or two negative images at the same time. This can improve the copying speed and greatly contribute to the speeding up of the copying machine.

Further, the exposure optical system of the present invention is not applied only to the exposure system such as a printer in which the electrophotographic process described above is used, and it is necessary to form both a positive image and a negative image. It is needless to say that the present invention can be applied to an exposure system such as an apparatus for forming a positive image and a negative image on a microfilm, and the same effect can be obtained in this case as well.

[0037]

Since the present invention is configured as described above, it has the following effects.

According to the first and second aspects, if the image light of either the positive image or the negative image is generated in the first optical path on which the image light is projected by the first projection means, Since a negative image or a positive image in which the image light generated in the first optical path is inverted is generated in the second optical path on which the image light is projected by the second projection means, positive-negative switching is performed. Without this, there is an effect that a positive image and a negative image can be efficiently formed from one image signal.

In the third aspect, two printers for positive image and negative image are used,
Since both positive and negative images can be obtained at the same time without changing the settings inside the printer each time, it is possible to efficiently study the design and the like.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an exposure optical system according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing an arrangement relationship of each component of the exposure optical system shown in FIG.

FIG. 3 is a schematic configuration diagram of an exposure optical system according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rod-shaped light source 2 Cylindrical mirror 3 Gradient distribution type lens array 4 Optical deflection element 5a, 5b Projection lens 6a, 6b Photosensitive drum 7 Optical deflection drive circuit 8 Image signal generation circuit 9a, 9b Mirror

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location G03G 15/04 111

Claims (3)

[Claims] 1. A light source, a light deflection element in which a plurality of deflectable minute reflecting surfaces are linearly provided, and a means for irradiating a light flux emitted from the light source onto the plurality of minute reflecting surfaces substantially uniformly. And an angle of each of the minute reflecting surfaces is set to first and second angles according to an image signal, and image light is generated by the reflected light, the angle is set to the first angle. First projection means for projecting a first image light generated by the reflected light of the minute reflecting surface, and a second image generated by the reflected light of the minute reflecting surface set at the second angle. An exposure optical system comprising: a second projection unit that projects light. 2. The exposure optical system according to claim 1, wherein the first image light generated by the reflected light of the minute reflecting surface set to the first angle and the minute image light set to the second angle. An exposure optical system characterized in that the second image light generated by the reflected light from the reflecting surface is image light generated from one image signal, and has a positive and negative relationship with each other. 3. A printer using the exposure optical system according to claim 1 or 2, wherein the exposure optical system has first and second photoconductors to which an electrophotographic process is applied. The two different image lights thus generated are applied to the first and second photoconductors to form latent images, and the latent images formed on the first and second photoconductors are output as print images. A printer characterized by: