JPS61275717A - Optical shutter device - Google Patents

Abstract

PURPOSE:To control the position of dielectric liquid in a container, to control the transmission state of light and to improve reliability and speed up operation by providing the dielectric liquid in the container movably and controlling an electric field established in the container. CONSTITUTION:When switch contacts 7a and 7c are connected to each other, an electric field is established between a common electrode 3 and an on electrode 5 and the liquid 2 is therefore attracted to an area where the electric field is intense and positioned between the electrodes 3 and 5. In this state, incident light 8 passes through a shutter device and guided out as projection light 9. When switch contacts 7b and 7b are connected to each other, on the other hand, an electric field is produced between an off electrode 4 and the common electrode 3 and the liquid 3 moves to an area where the electric field is intense with its electric strain force and is positioned in the opposite area of the electrodes 3 and 4. At this time, the incident light 8 is cut off by the liquid 2, so the projection light 9 is not guided out. The time required for the movement of the liquid is short, so the light is brought under on/off control at a high speed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical shutter device that controls on/off the passage of light, and more particularly, it relates to an optical shutter device that controls the passage of light on and off, and more particularly, it relates to an optical shutter device that controls the passage of light on and off. The present invention relates to an optical shutter device that controls the transmission state of light by controlling its position.

A typical optical shutter device has conventionally used a liquid crystal, but this has the disadvantages of slow response speed and small on/off ratio. Therefore,
When using LCD.

There are problems such as the inability to increase the recording speed of the incorporated electrical equipment, the low contrast of one image, the lack of a latent image margin, the tendency for background stains, and the low density.

1- The present invention has been made in view of the above points, and aims to eliminate the drawbacks of the prior art as described above, and to provide a high-speed, highly reliable, and low-cost optical shutter device. shall be.

The present invention provides an optical shutter device suitable for use as an optical writing device that controls on/off of light from a light source to form an electrostatic latent image on an image carrier such as a photoreceptor. The zero-light shutter device is suitable for use as an optical writing device for plotters such as printers, facsimile machines, and copying machines.

The optical shutter device of the present invention provides a movable dielectric liquid in a container, and controls the position of the dielectric liquid in the container by controlling the position of an electric field formed in the container. In a preferred embodiment of the present invention, the light-transmitting device is characterized by controlling the transmission state of light passing through the device. a transparent container, and at least half of the volume of the container is filled with an opaque dielectric liquid that does not transmit light.

An optically transparent common electrode on one side with the liquid in between, and a pair of optically transparent on and off electrodes on the other side are provided on the wall of the container, respectively, and the common electrode and the pair of on and off electrodes are provided on the wall of the container. It is characterized by controlling the passage of light by selectively generating an electric field between the electrode and the electrode.

Hereinafter, a specific embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic diagram showing the basic configuration of the present invention. As shown in the figure, the single-light shutter device has a roughly rectangular container 1, and the inside of the container 1 is electrically connected. A dielectric and optically opaque liquid 2 is contained therein. The container 2 is also desirably made of an optically transparent material and is further desirably electrically insulating.On a pair of opposing wall surfaces of the container 1, counter electrodes are provided. In the illustrated example, a common electrode 3 is provided on one inner wall surface of the container 1 . The common electrode 3 extends over almost the entire surface of its wall, and is preferably made of a transparent material 1, such as ITO.On the other hand, on the inner wall facing the common electrode 3, a pair of on and Off electrode 4
In the illustrated example in which electrodes 4 and 5 are provided, the on and off electrodes 4 and 5 are each about half the size of the common electrode 3.

These are also formed as transparent electrodes such as I'TO.

Further, the common electrode 3 is connected to the common contact 7C of the changeover switch 7 via the power source 6, while the on electrode 5 is connected to the contact 7a of the switch 7, and the off electrode 4 is connected to the contact 7a of the switch 7.
connected to b. Incident light 8 from the light source passes through the off electrode 4
In the illustrated state, the light is emitted as emitted light 9 through the container 1, the off electrode 4, and the upper half of the common electrode 3. In the illustrated example, more than half of the volume of the container 1 is filled with the dielectric and opaque liquid 2.

Next, the operation of the present optical shutter device having one or more configurations will be explained. In the state shown in FIG. 1, since the contacts 7a and 7b of the switch 7 are connected, an electric field is formed between the common electrode 3 and the on-electrode 5, and therefore the liquid 2 is in a region with a high electric field. Since it is pulled, it is located between electrodes 3 and 5.

In this state, incident light 8 from the light source passes through this shutter device and is extracted as emitted light 9.

On the other hand, when the switch 7 is operated to connect the contacts 7b and 70, an electric field is formed between the off electrode 4 and the common electrode 3, and the liquid 2 is moved to the area where the electric field is high due to the electric strain force. As a result, the liquid 2 moves to the area where the electrodes 3 and 4 face each other and blocks the incident light 8, so that the emitted light 9 is not extracted.

Further, when the switch 7 is operated to connect the contacts 7a and 70, the state shown in FIG. 1 is restored again, and the incident light 8 is extracted as the emitted light 9. In this way, by operating the switch 7 and controlling the position where the electric field is formed, it is possible to control the position of the liquid 2 inside the container 1 and turn on/off the light.

FIG. 2 shows a more specific embodiment of the present invention, in particular an example in which the switch 7 in FIG. 1 is constituted by an electronic switch. That is, the input terminal to which image data is input is NP.
It is connected to the base of the N transistor 10 , and its collector is connected to the off-electrode 4 and to one end of the resistor 13 . Note that the other end of the resistor 13 is connected to the power supply voltage V. Further, the emitter of the transistor 10 is connected to ground together with the common electrode 3. Also, the base of the transistor 10 is connected to another NPN via the inverter 12.
It is connected to the base of a transistor 11 , and the collector of the transistor 11 is connected to the on-electrode 5 and also to the power supply voltage V via a resistor 14 . Further, the emitter of the transistor 11 is connected to ground.

The image data is binary data and has a binary state of high and low. When the input image data is at a high level, the transistor 10 is turned on and the transistor 11 is turned off, so that an electric field is formed between the common electrode 3 and the off electrode 4, and the liquid 2 flows as shown in FIG. It is located between electrodes 3 and 4 as shown in FIG. On the other hand, when the 1 image data is at a low level, the transistor 10 is turned off and the transistor 11 is turned on, so that an electric field is formed between the on electrode 5 and the common electrode 3, and the liquid 2 is formed between the electrodes 3 and 5. Moving.

The movement of the dielectric liquid as described above will be briefly explained. For convenience, the electrical strain force induced in the liquid is f = (E”/2)f, (ε-1), where E: electric field strength, E: dielectric constant of the dielectric liquid. If the mass of is m, then the velocity is.Now,
For example, if inter-electrode distance Ia1 = 100 microns, ε = 4, and specific gravity = 1.5, then v = 1.9X10'V (i+
/5ee) Here, V: potential difference. The time t required for the liquid to move 1 mm is t = 5.3X 10-''/V (see), and the shutter operation is performed in a sufficiently short time.
As the dielectric liquid, it is possible to use, for example, hexane, heptane, benzene, methylal, etc., and if desired, it is also possible to add a coloring agent to these liquids to increase the opacity.

As explained in detail above, according to the present invention, a high speed, small size,
Moreover, it is possible to construct a low-cost optical shutter.The invention is easy to control, so the operation is reliable and accurate.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the principle of the present invention, and FIG. 2 is a schematic diagram showing one example of a specific implementation of the present invention. (Explanation of symbols) 1: Container 2: Dielectric liquid 3.4.5: Electrode 8: Incident light 9: Emitted light Patent applicant Rico Co., Ltd. - 1st solid

Claims (1)

[Claims] 1. A dielectric liquid is movably contained in a container, and
A means for selectively generating an electric field at a first position set in advance in the container and a second position separated from the first position is provided, and the electric field is selectively applied to the first position and the second position. An optical shutter device for generating and moving said dielectric liquid to control the passage of light through said container.