JPS62198882A - Imaging printer - Google Patents

Abstract

PURPOSE:To simplify a scanning system and to solidify a scanning means by forming a primary image on a liquid crystal light valve, enlarging and projecting this primary image onto a photosensitive body, and forming a secondary image (latent image). CONSTITUTION:A scan in the X direction is executed by using a laser 19, and a solid polarizing system such as an AO polariscope, etc. or its equivalent device, a scan in the Y direction is executed by a galvanomirror or its equivalent means, and when a primary image is written serially on a liquid crystal light value 18 by a light beam, the primary image is held in the light valve 18 for a white. A light beam from a projected light light source 15 is projected as a reflected image to a photosensitive body sheet 22 through lenses 16, 17 and a latent image is formed, and this latent image is made to form a toner image by a toner developing device 25 and transferred and fixed to paper 27. By using a liquid crystal light valve of a small area, the scan angle and the width become smaller, a solidified optical write device can be applied, and the titled device can be made small in size.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printing device f! which is one of the peripheral hardware of computers and the like. (Printer), %VC Page printer.

[Summary of the invention]

The present invention involves writing a print data 4Ik onto a liquid crystal light pulp from an optical writing device to form a primary image, and applying light from a light source such as a flash light source to a photoreceptor on a sheet. This is a page printer that obtains print output by printing out a secondary image on top of the printer and printing out the secondary image.

[Conventional technology]

The first order of calculations shows the printing principle of a typical conventional page printer. An electrostatic latent image is formed line serially on a photosensitive drum 1 using light. After developing this electrostatic latent image using toner, this pattern is transferred onto paper and fixed. The lufration process for fixing this electrostatic latent image onto paper is generally called a curl non-processed process, and is not directly related to the present invention, so its description will be omitted.

As a means for forming this latent image, a scanning method using two laser beams is used. Naturally, the beam has good directivity, so it scans in the horizontal direction using a polyhedron.

[Problems that the invention hopes to solve]

In such a system, the latent image form Ili! 5 ■Means for scanning the beam become complicated and highly accurate? request. ■The formation speed is restricted and slow by drawing the preparation on the serial. ■ Highly accurate mechanical parts such as drums and polyhedrons (b) - require advanced adjustment 8-1! and are susceptible to impact.

There is a serious drawback.

The object of the invention is therefore to eliminate this drawback.

[Elaborate means to solve problems]

The present invention forms a primary image on a liquid crystal light pulp and then uses projection light to transfer this primary image to a secondary or latent image on a photoreceptor sheet or equivalent material. Output image?
It is something that forms.

[Effect]

Figure 2 schematically illustrates the invention. A liquid crystal light pulp 7 is written onto a photoreceptor 5 having a sheet shape or a flat surface (which may be partial), and the next primary image is projected using a lens 6 and a projection light source 9.

A primary layer is formed on the liquid crystal light pulp by using 8 beams of Kenza light. The difference between the optical writing device for this liquid crystal light pulp 7 and the conventional optical writing device shown in the fs1 diagram is: - The liquid crystal light pulp of the present invention has a much smaller area than the drum 1, so the writing device is small and simple. 5. The writing power is much smaller than that of the liquid crystal light pulp, and if the power is the same, it is possible to increase the speed. Therefore,
If a liquid crystal light pulp is used to form an image on the photoreceptor through a small-area primary layer, high-speed, high-density print output can be obtained. Also, in conventional optical writing devices, scan l! (Scanning angle) is large and only polyhedral mirrors can be used -) However, by using a small area liquid crystal light pulp, the scanning angle and width become smaller and it becomes solid, making it a fluorescent writing device? Application of hZ allows for miniaturization.

〔Example〕

FIG. 3 illustrates the present invention in detail. First, a laser 19 and a polarizer are used to place a light on a liquid crystal light pulp 18.
Form the next image. Next, the light from the projection light source 15 is projected onto the photoreceptor sheet 22 as a reflected image through lenses 16, 17, thus forming a latent image. This latent image? A toner image is formed by the toner developing device 25 and transferred and fixed onto a sheet of paper 27.

There are various means for obtaining a printout from a latent image or secondary image, and any of them can be applied to the present invention, whether electrostatic or electromagnetic. It is obvious that the present invention can be applied to the photoreceptor even if it is not in the form of a sheet, as long as it has a material or shape that projects projected light and forms a secondary image. for example.

This also includes not projecting the entire screen at once, but dividing it into parts and compositing them.

As a method of projecting the primary image onto the liquid crystal light pulp, a transmission type is also possible instead of the reflection type as shown in FIG.

FIG. 4 shows an example of a liquid crystal light pulp and an optical writing retraction device used in the present invention. The upward direction is represented by the X direction and the depth direction hSY. LCD light pulp is glass 3
Between 1.34 and 32.53, transparent electrode 32.53 and liquid crystal 44. Semiconductor 1Il136. In the middle thereof, there is a dielectric reflective film 35 which reflects the projected light from the pressure and is an insulator. Note that this is the seal part of the 37th liquid crystal. On the other hand, the optical output of the laser 43 is scanned in the X direction using a solid-state polarization system such as a zero-input polarizer or an equivalent device. Although this lens is used to correct the optical path difference between the center and the periphery of the 40th scale, it is not essential.

Further, the Y direction is carried out by a galvano mirror 41 or equivalent means, and a 5° galvano mirror is sufficiently inexpensive and fast for use in the present invention. The light pulp shown here is a well-known one, and apart from the dielectric film, its structure and functions are well known. A bias voltage is applied to the two transparent electrodes 52 and 55, and when the optical input f+% and Px are low, the bias voltage ht is applied only to the semiconductor film and not to the liquid crystal.

At this time, a light beam h'' is input from the optical writing input amount on the right side, and the source location is optically excited in the semiconductor film to generate carriers.

The resistance of the liquid crystal layer is high (lower than the dark resistance of the semiconductor layer),
Since it is capacitive, this signal is accumulated and remains in this state for a while even without optical input. Therefore, when a primary image is serially written with a light beam, the primary image is retained within the light pulp for a while. When projected light is input to this primary image, a secondary light source that is much more powerful and expanded than a laser beam can be obtained. This is the so-called optical amplification and expansion effect.

In the liquid crystal light pulp shown in FIG. 4, the most complicated structure or formation is the dielectric reflective film 35, which is formed by laminating many layers of insulating films having various refractive indexes. The conventionally known Imito pulp is designed so that if even a small amount of incident light h''-1 from the left leaks into the semiconductor film, the image quality will deteriorate significantly.Of course, it can be used as is, but uninvented methods can be devised to avoid this. For example, although the reflection performance is not good, it is possible to use a reflective film with a simple structure and formation method, or to use a transmission type. The reason is that it is much slower, and that a fu->vouche light source, such as a strobe light source, is used as the projection light source.

FIG. 5 shows a transient state of light emission and liquid crystal response.

Primary image h: After writing is completed, incident light is projected, and if this incident light leaks into the semiconductor film, photocarriers will be generated on the entire surface of the semiconductor film, and (c) the bias voltage will increase across the entire surface of the liquid crystal. (B) The liquid crystal has a slow transient response, and 1
It takes some time for the next image to be erased. Therefore 1
If a light source (O)k that emits TK flash light for a period until the next image is erased is used, a secondary image can be obtained without any loss of primary gI.

Generally, the response of a liquid crystal takes several tens of milliseconds, so
By applying a flash xenon lamp or the like that emits light within 10 m5ec, sufficient light output can be obtained in a short period of time.

FIG. 6 is an example of a nine-liquid crystal light pulp produced by applying the above-mentioned idea. Instead of a dielectric reflective film, a finely divided metal reflective film 11671 is used. The size of this minute metal film may be slightly smaller than the limit of one resolution. The problem can be solved by the above-mentioned combination 6' in which the projected light leaks into the semiconductor film through the gaps in the finely divided metal film. This film is much easier to form than multilayer dielectric films. For example, division of 10 μm or less is performed using a or N-type membrane. , IK7 shows another embodiment of the invention. The light pulp shown here does not use any reflective film and is a transmission type.

A rotating mirror 80 switches the light input to the liquid crystal light pulp between writing light and projection light. A primary image is created on the light pulp using a laser beam 81 and a polarizer (scanning device) 82. Next, the rotating mirror was phased 908 times by a flash projection light source.

A secondary image is projected onto the photoreceptor sheet 78.

〔Effect of the invention〕

By forming a primary image using a liquid crystal light pulp and projecting an enlarged image onto a photoreceptor from this primary image, a second image is created.
The next image (latent image) 8- is formed, and is A4. /Iz, which used to scan as wide as or B4, *The invention simplifies the scanning method by reducing the scanning width to just a few tans, and also makes it easier to achieve accuracy. The scanning means is solidified. ■Since writing is done on the liquid crystal, less writing power is required, and the scratch formation speed is increased. ■High-precision mechanical parts h'
-It is an effective phenomenon that can be reduced.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the principle of a conventional optical printer. Figure 11E2 is a W diagram of the page printer of the present invention. FIG. 3 is a schematic diagram of a page printer according to the present invention using a liquid crystal light pulp. FIG. 4 is a block diagram of the light pollution exit device and liquid crystal light pulp used in the present invention. FIG. 5 (α) and (b) show the response of the liquid crystal used in the present invention,
The graph which shows an example of the relationship of the light emission of a projection light source. FIG. 6 shows an example of reflective di-liquid crystal light pulp used in the present invention. FIG. 7 shows an example of a transmission type liquid crystal light pulp used in the present invention. Applicant Seiko Epson Co., Ltd. 1, shit ! Figure 4 Figure 6 Figure 7

Claims (2)

[Claims] (1) In a printing device that forms a latent image on a photoreceptor with light, develops the latent image with toner, fixes the toner on paper, and outputs it, a primary image is formed on liquid crystal light pulp. , the primary image is enlarged onto the photoreceptor by a projection light source.
A printing device characterized by forming a secondary image (latent image) by projecting the image. (2) The printing apparatus according to claim 1, wherein the projection light source is a flash light source.