JP2795455B2 - Electrophotographic image recording device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a light deflecting unit of an electrophotographic image recording apparatus.

[Related Art] Recently, office automation (hereinafter referred to as “OA”)-related devices have rapidly become popular, and characters, graphics, photographs, and the like are output to a printer, which is a microcomputer or office computer output device. For printing, high resolution and high speed are required.

Therefore, an electrophotographic printer can print at high speed,
In addition, since it can record on plain paper, it is widely used in the OA field, and the following are known.

An electrostatic recording device that gives an image signal to a laser semiconductor to emit light, reflects the light by a rotating polygon mirror, and forms an image by forming an image of the reflected light on a photosensitive drum.

A recording device using a scanner that operates a reflecting mirror that reflects light from a light source to form an image on a photosensitive drum by an electric field corresponding to an image signal (Japanese Patent Publication No. 59-17525).

[Problems to be Solved by the Invention] In the above-mentioned conventional technology, when light emitted from a laser semiconductor is imaged on a photosensitive drum by a rotary polygon mirror, a laser optical system has a long optical path length and a rotary polygon mirror or the like. However, there are disadvantages that the apparatus has a large size, increases noise, and lacks reliability. on the other hand,
When light from a light source is imaged on a photosensitive drum by a reflection mirror driven by an electric field corresponding to an image signal,
In order to obtain a sufficiently high-speed response, the thickness of the reflecting mirror must be made sufficiently thin (about 0.2 to 0.5 μm).
The reflection mirror is easily deformed, and furthermore, the reflection mirror fluctuates due to the influence of wind, vibration, and the like around the reflection mirror, so that a clear image cannot be obtained during image formation. Further, as for the electric field for operating the reflection mirror, the driving power for generating the electric field is very small, but the driving voltage is as high as several tens of volts, so that the cost of the driver element is high and the practicality is lacking. There are drawbacks.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned drawbacks of the related art, and provides an electrophotographic image recording apparatus including a light deflecting element whose reflection surface does not fluctuate due to the surrounding environment and which is easy to manufacture. The purpose is to:

[Means for Solving the Problems] The present invention relates to an electrophotographic image recording apparatus which includes a light source and reflects light from the light source to form an image on a photosensitive drum to record an image. A closed space is formed with a thin reflective layer that reflects light, a heating source is provided in the closed space near the reflective layer on the substrate, and the closed space is filled with a liquid. And a signal power supply for applying a drive signal to each heating source of the light deflecting element in accordance with an image signal of an image to be recorded.

Further, the light deflecting element may be housed in a transparent sealed container.

Furthermore, a Peltier element for heating or cooling the closed container, a temperature detector for detecting the temperature in the closed container, and a drive power supply for driving the Peltier element according to the detected temperature of the temperature detector are provided. It is a thing.

[Operation] According to the present invention, a driving signal corresponding to an image signal of an image to be recorded is applied from a signal power supply to each of the light deflecting units of the light deflecting element to drive each of the heating sources. As a result, the liquid filled in each light deflecting unit is heated to generate bubbles inside, and the pressure deforms the thin reflective layer of each light deflecting unit to deflect the light from the light source, thereby causing the photosensitive drum to deflect. Image.

Further, by housing the light deflecting element in a transparent closed container, it is not affected by the surrounding environment, and furthermore, a Peltier element for heating or cooling provided in the closed container is provided in the closed container. By controlling the temperature, the temperature in the closed container can be kept constant.

Example Next, an example of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the electrophotographic image recording apparatus of the present invention.

In this embodiment, the light deflecting element 1 receives a drive signal corresponding to an image signal of an image to be recorded from a signal power supply 2 and reflects light 3a from a light source 3 such as a halogen lamp, and the reflected light 3b The light is irradiated onto the photosensitive drum 6 through the lens 5 attached to the light shielding plate 4.

The photosensitive drum 6 is made of a photoconductor 62 such as amorphous silicon, selenium or an organic semiconductor, and a metal cylinder such as aluminum.
The surface is uniformly charged by the charging device 7 while rotating in the direction of the arrow, and the reflected light 3b
Is irradiated to form an electrostatic latent image. This electrostatic latent image is
A colored powder developer (hereinafter, referred to as toner) is applied to the photosensitive drum 6 by the developing device 8 to be visualized. The toner adhered to the photosensitive drum 6 is transferred to the recording paper 10 by the transfer means 9, and the toner on the recording paper 10 is fixed by the fixing device 11. Further, the residual toner remaining on the photosensitive drum 6 is removed by the cleaning device 12 and reused.

Next, the configuration of the light deflecting element 1 will be described with reference to FIG.

In this light deflecting element 1, a hafnium boron (HfB ₂ ) layer having a thickness of 0.2 to 0.3 μm is formed as a heater 102 as a heating source on a silicon substrate (SiO ₂ ), and aluminum electrodes 103 and 104 are formed on the upper surface thereof. Is deposited to a thickness of 5 μm, an SiO ₂ layer having a thickness of 1 μm is formed as the insulating layer 105, and tantalum is provided as the protective layer 106.
The periphery of 06 is covered with resin 107. In addition, the protective layer 106
The upper part of the resin 107 is a space, and the upper surface thereof is formed by laminating a 1 μm-thick polyethylene terephthalate (PET) laminated film 108 forming a thin reflective layer and a high reflectance deposited on the outside thereof. It is covered with a reflective material 109 such as a chrome layer or an aluminum layer.
A space between 107 and 107 is filled with polyethylene glycol or water as a liquid 110. In this light deflecting element 1,
The aluminum electrodes 103 and 104 are connected to the signal power supply 2, and the heater 102 is driven in response to a drive signal from the signal power supply 2 to heat the liquid 110. Then, by heating the liquid 110, air bubbles 111 are formed on the upper surface of the protective layer 106.
Is generated and pressure is applied to the inside, and as a result, the laminated film 10
The reflector 8 and the reflector 109 swell and deflect the light 3a as shown by the broken line in FIG. Also, this light deflecting element 1
Are divided into a plurality of light deflecting units 1a, 1b, 1c... According to the resolution required for image formation, and are installed in parallel with the axis of the photosensitive drum 6, as shown in FIG. The recording image area of the drum 6 can be irradiated. In FIG. 3, the layer structure in the optical deflection element 1 shown in FIG. 2 is omitted, and only the heater 102 is shown. Furthermore, each of the divided light deflection units 1a, 1b, 1c
Are individually driven by a drive signal applied independently by a signal power supply 2, and light 3 a from a light source 3 is deflected according to an image pattern and is irradiated on a photosensitive drum 6 through a lens 5.

Here, the deflection operation of the light deflection element 1 will be described with reference to FIG. FIG. 4 also shows only the heater 102 in the optical deflection element 1 as in FIG.

First, FIG. 4 (a) shows a state in which a drive signal is not applied from the signal power supply 2 to the light deflecting element 1, and the light 3a from the light source 3 is reflected by the reflector 109 of the light deflecting element 1. The light is guided to the photosensitive drum 6 as reflected light 3b.

Next, FIG. 4 (b) shows a state in which a signal pulse of 10 μsec to 100 μsec is applied as a drive signal from the signal power supply 2 to the light deflecting element 1, and the heater 102 is driven by the drive signal. Liquid 110 is being heated. Due to this heating, bubbles 111 are generated in the liquid 110 to generate pressure,
This pressure deforms the reflective layer of the laminated film 108 and the reflective material 109, and the light 3a from the light source 3 becomes reflected light 3c and does not reach the photosensitive drum 6.

Subsequently, FIG. 4 (c) shows a state in which the application of the drive signal from the signal power supply 2 to the optical deflecting element 1 is stopped in the state of FIG. 4 (b) described above.
The heating of the liquid 110 is stopped, and the liquid 110 is rapidly cooled naturally, and the high deflection element 1 returns to the state shown in FIG. 4 (a).

As described above, the drive signal corresponding to the image pattern to be recorded is applied to the heater 102 of the light deflecting element 1 to deform the reflective layer, whereby the light can be deflected according to the image pattern.

Next, a second embodiment of the present invention will be described with reference to FIG.

FIG. 5 shows a light deflection element 1 and a signal power supply 2 of the electrophotographic image recording apparatus.

In this embodiment, the light deflecting element 1 is housed in a closed container 13 made of transparent glass, plastic or the like under normal pressure or slightly pressurized. The light deflecting element 1 is
Is no longer affected by changes in the surrounding air pressure, and a constant pressure is applied to the reflective layers of the laminated film 108 and the reflective material 109, so that a stable deflection angle can always be obtained,
Failure such as leakage of the liquid 110 due to a change in ambient pressure is also eliminated. Further, since the reflecting surface of the reflecting material 109 is not stained, scratches or deformation due to cleaning are eliminated.

Next, a third embodiment of the present invention will be described with reference to FIG.

FIG. 6 shows the light deflecting element 1 and the signal power supply 2 similarly to FIG.

In this embodiment, similarly to the above-described second embodiment, the light deflecting element 1 is housed in a closed container 13, and the closed container 13 is filled with a heat conductor material 17 such as Freon gas. Further, a temperature detector 14 for detecting the internal temperature is inserted in the closed container 13, and notifies the drive power supply 15 provided outside the closed container 13 of the detected temperature. The drive power supply 15 drives a Peltier element 16 that heats and cools the closed container 13 attached to a part of the outer periphery of the closed container 13, and drives the Peltier element 16 according to the level of the temperature detected by the temperature detector 14. Is controlled to keep the temperature inside the closed container 13 constant. In this case, the laminated film 108 and the reflective material 109 forming the reflective layer of the light deflecting element 1 are suitably made of aluminum or copper foil having good heat conductivity.

In this embodiment, the interior of the closed vessel 13 is filled with the chlorofluorocarbon gas as the heat conductor material 17, but may be filled with a liquid such as fluorocarbon. In this case, the liquid 10 in the optical deflection element 1 is the same as the heat conductor material 17. Thus, the heat conductive material 17 of the closed container 13 and the liquid 10 of the light deflecting element 1 can be connected. Further, in this embodiment, the case where the light deflecting element 1 is housed in the closed container 13 and the temperature inside the closed container 13 is kept constant is shown, but the light deflecting element 1 is not housed in the closed container 13. In this case, it is conceivable to attach the temperature detector 14 and the Peltier element 16 directly to the light deflecting element 1 to keep the temperature of the light deflecting element 1 constant.

[Effects of the Invention] As described above, in the present invention, since the liquid is filled in the light deflecting element, the reflection layer is a thin film, but is not deformed, and is easy to manufacture. In addition, since the light deflecting element is housed in a closed container, the influence of changes in the surrounding environment such as wind and air pressure is shut off, and there is no adhesion of dust and dust. A stable deflecting surface can be secured, clear images can always be formed, and the handling of the optical deflecting element body is simplified. Furthermore, since the temperature of the liquid in the light deflecting element can be kept constant by holding the light deflecting element in the closed vessel and keeping the temperature inside the closed vessel constant, the signal power supply at the time of light deflection is used. By heating or cooling the liquid in the light deflecting element under a constant temperature condition, stable light deflecting becomes possible, and a clear image can always be formed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of the electrophotographic image recording apparatus of the present invention, FIGS. 2 and 3 are cross-sectional views showing one embodiment of the light deflecting element 1, and FIG. 5 and 6 are cross-sectional views showing another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Light deflection element, 1a, 1b, 1c, 1d, 1e ... Light deflection part, 2 ... Signal power supply, 3 ... Light source, 3a ... Light, 3b, 3c ... Reflected light, 4 ... Light shielding Plate 5, lens 6, photosensitive drum 7, charging device 8, developing device 9, transfer device 10, recording paper 11, fixing device 12, cleaning device 13, cleaning device 13 …… Closed container, 14… Temperature detector, 15… Drive power supply, 16… Peltier element, 17… Thermal conductor material, 61 …… Metal cylinder, 62 …… Photoconductor, 101 …… Silicon substrate, 102: heater, 103, 104: aluminum electrode, 105: insulating layer, 106: protective layer, 107: resin, 108: laminated film, 109: reflective material, 110: liquid, 111: air bubble .

Claims (3)

(57) [Claims] 1. An electrophotographic image recording apparatus comprising a light source and reflecting light from the light source to form an image on a photosensitive drum to record an image, wherein reflection of a substrate and a thin film for reflecting light from the light source is provided. A closed space is formed with the layer, a light source is provided in the closed space, in the vicinity of the reflective layer on the substrate, and further a plurality of light deflecting units in which the closed space is filled with liquid. An electrophotographic image recording apparatus, comprising: an element; and a signal power supply for applying a drive signal to each heating source of the light deflecting element according to an image signal of an image to be recorded. 2. An electrophotographic image recording apparatus according to claim 1, wherein said light deflecting element is housed in a transparent closed container. 3. A Peltier device for heating or cooling an airtight container, a temperature detector for detecting a temperature in the airtight container,
3. An electrophotographic image recording apparatus according to claim 2, further comprising a drive power supply for driving said Peltier element in accordance with the temperature detected by said temperature detector.