JPH0398045A - Image forming device - Google Patents

Abstract

PURPOSE:To simplify constitution and to reduce production cost by using a capsule paper having three-layered structure and a single laser corresponding to the photosensitive characteristic of the capsule paper. CONSTITUTION:The device is provided with the single lasers 20-22 corresponding to the absorption wavelength of the capsule paper 80 consisting of three layers such as a Y layer, an M layer and a C layer, a condensing lens 35 for converging laser light and a feedback mechanism 120 which detects a focusing position and always keeps the focusing position. The respective means are optically arranged so that the information of a Y picture element, an M picture element and a C picture element is simultaneously focused on the Y layer, the M layer and the C layer. Namely, owing to the action of such optical arrangement, the Y picture element, the M picture element and the C picture element are slightly deviated and simultaneously focused on the respective layers to arrange picture element information. Thus, the constitution is simplified and an inexpensive full color image forming device is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to full-color image output devices such as color copiers, color printers, and color plotters.

[Prior Art] Conventionally, capsule paper in which microcapsules containing yellow, magenta, and cyan dye precursors that are cured by light of different wavelengths are supported in the same layer is known. In order to scan and expose such capsule paper with laser light to obtain a full-color image, laser oscillators for each curing wavelength were required.

[Problems to be Solved by the Invention] However, since such a device uses three types of lasers, the configuration becomes complicated and it is difficult to keep the manufacturing cost and product cost low.

The present invention was made to solve the above-mentioned problems, and by employing one type of laser and a capsule paper with a three-layer structure, a full-color image forming apparatus with a simple configuration and low cost is provided. The purpose is to provide.

[Means for solving the problem] To achieve this purpose, Honbukkawa's image forming apparatus
In an image forming apparatus that exposes a capsule paper consisting of three layers: layer, M layer, and C layer, a single laser corresponding to the absorption wavelength of the capsule paper, a condensing lens to narrow down the laser beam, and a focus are used. Each means has a feedback mechanism that detects the position and always maintains the focus position.
Pixel. It is characterized in that it is optically arranged so that M pixel and C pixel information are simultaneously focused on the Y layer, M layer, and C layer, respectively.

[Function] According to the present invention having the above configuration, the three-layered capsule paper capsule has the property of reacting and solidifying only when the intensity of a single laser beam exceeds a certain level. . In other words, when it is below the threshold value, it is transmitted, and when it is above the threshold value, it is absorbed. For example, when light is focused on the middle M layer by the condensing lens, the light coming to the upper layer is below the threshold and passes through, and when the light is focused on the M layer, it exceeds the threshold and an absorption reaction occurs. Since the threshold value is not exceeded even in the C layer, no reaction occurs.

Further, the optical arrangement described above has the effect of slightly shifting the Y, M, and C pixels, focusing on each layer at the same time, and arranging pixel information.

The feedback mechanism also serves to detect the distance between the condenser lens and the paper, and to ensure that the focus point is always on each layer.

[Example] An example embodying the present invention will be described below with reference to the drawings, as shown in FIG. 1. The Y, M, and C semiconductor lasers 20, 21, and 22 are intensity-modulated according to commands from the concentration controller 10, and are input to the respective fibers. Also, the wavelength at which the capsule particles do not react at all (e.g.
A semiconductor laser having a wavelength of 930 nm) is also input into the Y fiber by a light mixing optical element. The output ends of the fibers are arranged as shown in FIG. 1 and focused on each layer by a lens 70. At this time, in layers other than the focus layer, the energy density becomes extremely low and does not exceed the threshold, so that no photochemical reaction occurs and the light is transmitted. Details are shown in Figure 2. As shown in Figure (a), the amount of light transmitted through an object with an absorption coefficient M and a thickness t is generally:
t=I. It is expressed as e-#(Io)-i.

In other words, when the absorption coefficient has the relationship shown in FIG. 2(b), it means that the light passes through well in the case of weak light. For example, if you are focusing on the M layer, M is large;
In the Y and C layers, M becomes small. For the above reasons, Y layer, M layer,
The C layer can be exposed separately.

In addition, a laser beam for focus detection is also irradiated onto the top layer as shown in FIG. is focused on.

In addition, in front of this sensor, a bandpass interference filter 100 matching the wavelength of the detection laser is installed.
Even if there is a reflection of the writing laser beam, it will not be a hindrance. The patterns at that time are shown in FIGS. 3(b), 3(c), and 3(d). Furthermore, FIG. 4 shows a pattern when focusing in front of the capsule. 10 counts, 100 counts, 1
000 count indicates the number of pixels constituting the one-dimensional photosensor that are at H level due to the detection laser light.

When using a lens with large N and A (ex-N.A
-0.8 or 0.9) The pixels that are at H level can be easily distinguished because there is a difference of about one digit between them. Also the fourth
In the case of a pattern as shown in FIG. 3(b), by setting the threshold of the combo barrette to a high value, the waveform is shaped as shown in FIG.

That is, if the count exceeds 10, the imaging lens stage is moved to the light source side. Also, if the force and count are 10 or less, the stage is moved to the capsule paper side. This way you always maintain focus. The block diagram of the feedback circuit is shown in Figure 5 (
Shown in a) and (b). The output of the one-dimensional foot sensor 200 enters an amplifier 210, is amplified, and is sent to a comparator 2.
20, the waveform is shaped into a square wave. As shown in FIG. 3, only when the square wave is at H level, it is counted by the counter 240, compared with a set value from the CPU 260 (for example, 10 counts) by the comparator 250, and positive/negative information is sent to the stage driver 270. , perform minute control.

Since the fiber 40 is flexible, a half mirror 60, a stage 50, an imaging lens 70, a bandpass filter 100, and a one-dimensional sensor are integrated as a head.
, y, it becomes a full-color plotter, and if the capsule paper is wound around a drum and the head scans in the direction of the rotation axis, it becomes a full-color printer.

A modification of FIG. 1 is shown in FIG. 6. In Figure 1, Y focus. Although the X positions of M focus and C focus were slightly shifted, if they were arranged as shown in FIG. 6, each pixel information could be written in the same location at the same time. In the figure, 540 is a mirror, and 550 is a beam splitter.

Although a semiconductor laser is assumed in FIG. 1, a 4800 m gas laser 500 may also be used since light with a shorter wavelength is effective. At this time, the concentration modulation is performed by the modulator 5.
Intensity modulation is applied by 30. In addition, 52 in the figure
0 is a mirror, and 510 is a beam splitter.

[Effects of the Invention] As is clear from the detailed description above, since the three-layer capsule paper of the present invention and a single laser corresponding to its photosensitive characteristics are used, the structure is simple and the product cost and manufacturing cost are low. However, it is possible to provide an inexpensive full-color image forming apparatus.

[Brief explanation of drawings]

Figures 1 to 6 show embodiments embodying the present invention; Figure 1 is a diagram of the optical system, Figure 2 is an explanatory diagram showing that the non-focal area is not exposed, and Figure 3 is an illustration of the optical system. is a diagram of the focus state and the output waveform of the sensor, Figure 4 is a diagram of the output waveform when focusing in front of the Y layer, Figure 5 is a block diagram of the electric circuit for applying feedback, and Figure 6 is a diagram of the example. It is a figure which shows deformation. In the figure, 20, 21, and 22 are semiconductor lasers with the same wavelength, and 3
5 is a condensing lens, 70 is an imaging lens, 80 is a capsule layer, and 120 is a feedback circuit.

Claims (1)

[Claims] 1. In an image forming apparatus that exposes a capsule paper consisting of three layers: Y layer, M layer, and C layer, a single laser corresponding to the absorption wavelength of the capsule paper and a condensing lens for narrowing down the laser beam are used. and a feedback mechanism that detects the focus position and keeps the focus position at all times. 1. An image forming apparatus characterized in that the image forming apparatus is arranged as follows.