JPH08271933A - Movable film type display device and its production - Google Patents

Abstract

PURPOSE: To provide a movable film type display device which is high in reflection brightness and is low in electric power consumption. CONSTITUTION: Transparent films 14 to 16 of cyan, magenta and yellow exist on a white plate 5 which is a fixing part and cantilever beam-like movable films having these three-layered films as the display part 6 exist. The movable films are fixed at one end to a substrate. Movable electrode parts 2 on the movable films have potential differences between the movable electrode part and stationary driving electrodes 3 and are movable by electrostatic force. As a result, the display of arbitrary information is made possible. Matrix display is made possible when the movable films and the stationary driving electrodes 3 are arranged in a grid form.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a movable film type display device having a completely novel structure.

[0002]

2. Description of the Related Art A display used for portable information equipment is desired to be thin, lightweight and have low power consumption. Conventionally, a liquid crystal display (LC
D), plasma displays, flat CRTs, etc. are known. Among them, LC considering the power consumption etc.
D is the most suitable and has been put to practical use.

Of the LCDs, the one in which the display surface of the display is directly viewed is called the direct-view type. Direct-view LCD
There are a transmissive type that incorporates a light source such as a fluorescent lamp on the back side and a reflective type that uses ambient light. Of these, the former requires a backlight and is not suitable for low power consumption.
Therefore, the latter reflective type is most popular as a display for portable information equipment.

The reflective LCD has an ECB (Electrically
Controlled Birefrigence mode, GH (Guest
Host mode, TN (Twisted Nematic) mode, etc. are used. A polarizing plate is required when using the ECB mode or the TN mode. Since the light transmittance of the polarizing plate is about 40%, the utilization efficiency of light is deteriorated.

A polarizing plate is not necessary when using the GH mode, but a transmittance of 8 is required for full color display.
It is necessary to stack three or more layers of 0% monochromatic liquid crystal cells. Therefore, the utilization efficiency of light is not so high, and the display of paper white cannot be displayed with a reflectance of about 50% as a color display device.

In the case of color display, if an ECB mode or a GH mode is used, a color filter is not necessary, but the color reproducibility is low and the viewing angle dependency is large. When using TN mode, color is added with a color filter,
Since it is a reflective type, the light utilization efficiency becomes about 1/3 and it becomes dark.

In addition to these, in these, a TFT (Thin Film Transistor) is used as a switch.
r) or TFD (Thin Film Diode), etc., the aperture ratio becomes low.

If the light utilization efficiency is low and the aperture ratio is low, the reflection brightness is lowered and the screen becomes dark. By the way, even a reflective LCD does not have zero power consumption. This is because when a DC voltage is applied to the liquid crystal molecules, there is a fear of deterioration thereof, and therefore even when a still image is displayed, an AC voltage of 60 Hz or higher is driven. Power consumption is proportional to this frequency. On the other hand, if the size of the display device is not considered, a mechanical matrix display device used for a large bulletin board or the like is promising from the viewpoint of low power consumption. Since this is a mechanical type, it does not consume power when displaying a still image. In other words, once the operation stops, it does not move, so it has the effect of a non-volatile memory.
Therefore, the power consumption is zero.

As the most widely used mechanical matrix display device, one pixel is made up of a cube having a side length of several centimeters, four surfaces are colored with four types, and the other two surfaces are rotated about axes. There is a method to do. You can often see this method in the station square. However, the drawback of this method is that it can display only four colors.

As a solution to this problem, as shown in Japanese Patent Laid-Open No. 56-150786 (Right Elimination), the pixels are formed into pellets (plates) instead of cubes, a plurality of pellets of a plurality of colors are stacked, and these are staircased. 4 by making the screens overlap each other
There is a method to display more than colors. However, it is difficult to materialize this structure, and it has not been realized yet.

Since these have a complicated structure, they are said to be unsuitable for a small display device, and are mainly intended for a large display plate such as a signboard or a bulletin board in a plaza. The driving force also uses an electromagnetic motor or electromagnetic solenoid, and there is a limit to miniaturization. Therefore, it is not suitable as a small-sized and low power consumption display device for a mobile terminal.

The reason why the electromagnetic force such as the electromagnetic motor or the electromagnetic solenoid is unsuitable for a small-sized and low power consumption display device is that the electromagnetic force is proportional to the current and the number of turns of the coil. The fact that it is necessary to pass current means that it consumes power (however, still images do not consume power for the reasons described above), and that winding a coil is disadvantageous for miniaturization. Become.

On the other hand, the electrostatic force is suitable for small size and low power consumption. The electrostatic force is simply the force acting between the electrodes of the capacitor. As it is a capacitor, the current flows only for a moment and consumes almost no power. Further, since it is not necessary to wind the coil, it is advantageous for downsizing.

There is already a display device using such electrostatic force (Nikkei Electronics, December 12, 1977).
The Japanese issue, page 38), has already been commercialized as a large display board. In this structure, as shown in FIG. 32, the foil with the electrode is moved between the fixed electrode and the fixed electrode by electrostatic force, and
The colors can be displayed. That is, different colors are applied to the front and back of the foil, and the fixed electrode is also applied with a color, and two colors are displayed by moving the foil. One side of the foil and one of the fixed electrodes may be mirror-finished with an aluminum thin film.

However, this display device can basically display only two colors or three colors by using two foils. With this, full-color display cannot be performed. For example, suppose you select red, blue, and green as the three colors.
In this case, white, black, yellow, or other colors cannot be displayed on the entire screen. This is the reason why it is difficult to achieve full color in a reflective display device. If it is a light emitting type like a cathode ray tube, full color can be displayed only by distributing three colors of red, blue and green.

[0016]

The problems of the prior art are summarized above. A small size and low power consumption portable color display device is required, and the most promising reflection type L at present.
With a CD, you can make only dark ones with a reflectance of 50% or less, and you can not expect paper white full color display. In addition, this method does not completely reduce the power consumption to zero even for still images.

On the other hand, the mechanical matrix display can reduce the power consumption to zero in a still image, but at present, due to the complexity of its structure, there is only a large display device using electromagnetic force. Small display devices for terminals are not possible.

In addition, a display device which is suitable for a small size and uses electrostatic power of low power consumption can currently display only two or three colors per pixel. Therefore, full-color display cannot be expected.

The present invention has been made in view of the above-mentioned problems, and is a movable film type capable of realizing paper white and full color with high reflection brightness and low power consumption, and especially for still images with zero power consumption. An object is to provide a display device.

[0020]

In order to solve the above problems, a movable film type display device according to claim 1 of the present invention has a fixed portion of a first color, and a second portion which is exposed or hidden from this fixed portion. A movable film capable of taking in and out colors, a support capable of supporting the movable film in at least a direction perpendicular to the surface of the movable film, and the movable film being formed by bending the support by electrostatic force. It has a drive means that can be exposed or hidden from the fixed portion.

According to a second aspect of the present invention, there is provided a movable film type display device in which a fixed portion of a first color, a movable film which is exposed or hidden from the fixed portion and which allows a second color to be taken in and out, and a surface of the movable film. A support capable of supporting the movable film in at least a vertical direction with respect to the support, and a bimorph type capable of exposing or hiding the movable film from the fixed portion by bending the piezoelectric film formed on the support due to distortion of the piezoelectric film. It is characterized by having a piezoelectric film.

A movable film type display device according to a third aspect of the present invention is the movable film type display device according to the first or second aspect, wherein the bending motion of the movable film can be stopped at an arbitrary position by applying an electrostatic force. It is characterized in that a driving means is provided.

A movable film type display device according to a fourth aspect is the movable film type display device according to the first or second aspect, wherein a protective transparent plate is provided on the movable film, and the movable film or the fixed film is formed on the surface of the transparent plate. And a transparent electrode capable of stopping the bending motion of the movable film at an arbitrary position by applying an electrostatic force between the transparent electrode and the portion.

A movable film type display device according to a fifth aspect is characterized in that, in the first or second aspect, the movable film is stored under the fixed portion. A movable film type display device according to a sixth aspect is characterized in that, in the first or second aspect, the fixed portion is a white opaque film, and the movable film is a black opaque film.

According to a seventh aspect of the present invention, in the movable film type display device according to the first or second aspect, the fixed portion is a white opaque film, and the movable film is a cyan film.
It is characterized by a three-layered transparent film that is colored magenta and can be moved independently.

The movable film type display device according to an eighth aspect is the movable film type display device according to the seventh aspect, wherein the movable film is a four-layer structure in which a black opaque film is added in addition to the three colors of cyan, magenta and yellow. Is characterized by.

A movable film type display device according to a ninth aspect is a movable film which has a fixed portion of a first color, and which is exposed or hidden from the fixed portion so that a second color can be taken in and out, and a surface of the movable film. A support member capable of supporting the movable film in at least a vertical direction with respect to the movable member, and a driving unit capable of exposing or concealing the movable film from the fixed portion by bending the support member with an electrostatic force. It is characterized by including pixels and arranging the pixels on a plane in a matrix.

A movable film type display device according to a tenth aspect of the invention is characterized in that, in the ninth aspect, the electrostatic force applied to bend the movable film is formed by two electrodes sandwiching the movable film.

A movable film type display device according to an eleventh aspect of the present invention is provided with a first wiring for transmitting electric charges to the movable film according to the tenth aspect, and the first wiring transmits a signal line for transmitting image information. And two electrodes that are connected to each other and that generate an electrostatic force to bend the movable film are connected to respective wirings that charge them, and the wirings select the pixels to which the image information is to be transmitted. It is a line and is characterized in that dot matrix display is possible.

According to a twelfth aspect of the present invention, in the movable film type display device according to the ninth aspect, one of the wirings serves as a scanning line and the other is connected to a signal line, which enables a dot matrix display. It is characterized by that.

According to a thirteenth aspect of the present invention, in the movable film type display device according to the ninth aspect, the first film is provided with a first wiring for sending electric charges to the movable film, and the first wiring is a scanning line. In order to stop the movement of the display area of the film, there is an electrode that generates an electrostatic force and a second wiring that supplies an electric charge to the electrode. This second wiring also serves as a scanning line, and in order to bend the movable film. The two electrodes that generate electrostatic force are connected to the respective wires that apply electric charge to them, one of them is the scanning line, and the other is connected to the signal line, enabling dot matrix display. It is characterized by

According to a fourteenth aspect of the present invention, in the movable film type display device according to the tenth aspect, the eleventh, the twelfth and the thirteenth aspects, the potentials of the signal lines and the scanning lines are set to a floating potential, and dot matrix display is possible. It has a feature.

According to a fifteenth aspect of the present invention, there is provided a method of manufacturing a movable film type display device, wherein a fixed portion assembly member in which a plurality of fixed portions of the first color are connected to each other and a second color which is exposed or hidden from the fixed portion can be taken in and out. A step of preparing a movable film assembly member in which a plurality of possible movable films are connected at the root, and the fixed portion assembly member and the movable film assembly member are alternately arranged on the base substrate, and a protective substrate is arranged from above. And a process.

[0034]

According to the present invention, the movable film installed on the fixed portion is moved by the drive portion by electrostatic force, and this is used as a pixel, that is, a display portion to display a screen. Since a colored film is used to display the screen, no polarizing plate is required, and since there is no liquid crystal layer having low transmittance, the light utilization efficiency is improved. Further, since the driving unit is formed so as not to obstruct the display of the display unit, the aperture ratio becomes extremely high. As a result, the reflection brightness is increased. Also, since it is mechanical, it does not consume power when displaying a still image. In other words, once the operation stops, it does not move, so it has the effect of a non-volatile memory. Therefore, the power consumption is zero.

[0035]

EXAMPLES The details of the present invention will be described below with reference to examples. FIG. 1 shows an enlarged cross-sectional view of one pixel of a movable film type display device according to an embodiment of the present invention. In FIG.
A movable film 1 is composed of a movable drive electrode portion 2 and a display portion 6. Reference numeral 3 is a fixed drive electrode. Further, 5 is a white plate.

The base of the movable film 1 is fixed to a substrate (not shown), which is in a so-called "cantilever beam" state, and can be bent to either the left or the right in the figure.

Further, the bent portion which divides the display portion 6 of the movable film and the movable drive electrode portion 2 is adapted to be freely bent. As a display principle, there is a method in which the display portion 6 colored in black or another color is put into and taken out from the pixel area 36 through the gap between the white plates 5 to display black and white or color. As a method of moving the movable film, an electrostatic force that acts on the movable film 2 by applying a potential difference to the movable drive electrode portion 2 to one of the fixed drive electrodes 3 is used. In the movable film type display device described in this embodiment, the above-mentioned one pixel is two-dimensionally formed in a matrix to form a display device. 2 and 3 are cross-sectional views of the schematic overall configuration of this display device.

The ratio of the lengths of the display portion 6 and the movable drive electrode portion 2 of the movable film is preferably as large as possible as shown in FIG. 2, and particularly (length of the display portion 6) / (movable drive electrode portion 2).
The length) is preferably 0.01 to 0.1 in view of the ease of movement of the display electrode.

FIG. 2 is a cross-sectional view showing a black and white display.
The black display electrode 6 is put in and taken out from the gap of the white plate 5. FIG. 3 is a cross-sectional view in the case of color display, in which transparent films colored in 14 cyan, 15 magenta, and 16 yellow are put in and out from the gap of the white plate 5 to display the same color as the printed matter. For example, above 14, 15, 1
When a color other than 6 is output, yellow and magenta are overlapped in the case of red, cyan and magenta are overlapped in the case of blue, and cyan and yellow are overlapped in the case of green.

In the case of gradation display, the area gradation method is adopted and the colored film is applied only to a specific portion of the pixel region 36. For example, in the case of displaying pink, which is an intermediate color between red and white, yellow and magenta films are overlapped and displayed up to half the pixel area 36. By doing so, the area ratio of white and red in the pixel becomes 1: 1 and the intermediate pink can be displayed. This is the same as the gradation display method of the printed matter.

FIG. 4 is a perspective view showing the structure of one pixel capable of binary display such as monochrome display of the movable film type display device. In the following description, the above-mentioned parts are given the same numbers and their detailed description is omitted.

FIG. 5 shows an arrangement of movable films for color display which is a modification of the structure of one pixel of this embodiment. Cyan 14, magenta 15, and yellow 16 are composed of three movable films that have a transparent display section, and the above three colors can be output to the pixel section from the gap of the white plate in any combination. It has become.

FIG. 6 is also a modification of the one-pixel structure of this embodiment, in which the display pattern extends from the central portion of the display portion, and the structure is more balanced than the modification of FIG. However, it has an effect on an ultra-high-definition display in which pixels are not visually recognized due to color shift.

Next, the relationship between the movable film 1 and the movable electrode portion 2 will be described with reference to the sectional structure of the movable film 1 itself. If the movable film 1 is made of a conductive material such as a metal foil, it can also serve as the movable electrode portion 2 itself. However, when the movable film 1 is made of an insulating substance such as a polymer film or a glass film, it is necessary to bring a conductive substance into close contact with the movable film 1.

FIG. 7 is a diagram showing the position of the movable electrode portion 2 made of a conductive material with respect to the movable film 1 of this embodiment. Although the manufacturing method will be described later, in the case of FIG. 7, the movable electrode portion 2 made of a conductive material is provided on the side of the movable film 1 where the display portion 6 is located.

FIG. 8 is a modification of the structure of FIG. 7, and an insulating film 9 may be further coated on the conductive material of the movable electrode portion 2 as shown in the figure. Although FIG. 9 is also a modification of the structure of FIG. 7, the position of the movable electrode portion 2 may be brought to the opposite side of the display portion 6 as shown.

Further, as will be described later, it is necessary to give conductivity to the display portion 6 for holding operation. In FIG. 10, the conductive portion (electrode) for holding operation is made of the same conductive material as that of the movable electrode portion 2 described above. At this time, the conductive material may be made transparent.

Further, as shown in FIG. 11, a conductive portion for holding operation may be provided while avoiding the portion of the display area which is actually used.
FIG. 12 shows a modification in which the movable electrode portion 2 and the conductive portion 10 for holding operation are separate electrodes. Especially, 10 is preferably a transparent electrode.

In FIG. 13, the movable film 1 itself is the electret 11, and although it is not conductive, the electric charge in the electret is attracted to the electrostatic field to move the movable film.

FIG. 14 shows a modification in which the materials of the polymer of the display section 6 and the movable electrode section 2 are changed. The display section 6 needs to be transparent for color display, but the movable electrode section 2
Does not need to be transparent, but it is preferable that it has heat resistance for the sake of metal coating and insulating film coating. Therefore, it is preferable to use a transparent film such as polyester for the display portion 6 and heat-resistant polyimide for the film near the movable electrode portion. As a method for adhering the films, an adhesive may be used, but if the films are thermoplastic, they may be adhered by melting with heat.

Further, although FIG. 15 is also a modification, the bending force of the bimorph type piezoelectric film 7 shown in the figure may be used as the driving method of the movable film 1 as described above. 40
Is a power source for applying a voltage to the bimorph type piezoelectric film 7.

Next, details of the operation principle will be described. First, as shown in FIG. 16, a potential difference is applied between two fixed drive electrodes 3 sandwiching the movable film 1 to generate an electric field. At this time, the fixed electrode portion 3 is attached to the movable electrode portion 2 of the movable film 1.
The same potential as either one of them is applied. Then, the movable electrode portion of the movable film is pulled by one of the fixed drive electrodes 3 and comes into contact with it to stop. The capacitor formed between the movable electrode portion 2 of the movable film 1 and the fixed drive electrode 3 will be referred to as a drive capacitor (Cd; Driving Capacitor).

If the potential relationship between the two fixed drive electrodes 3 is reversed, then the movable film 1 is pulled in the opposite direction. The force F acting on the movable film at this time can be expressed by the following equation (1).

F = εSV ² / (2d ² ) ... (1) where ε is the dielectric constant, S is the movable electrode portion 2 or fixed drive electrode 3, whichever is smaller, and d is the movable area. The distance between the electrode portion and the fixed drive electrode is shown.

For example, assuming a pixel pitch of 300 μm, d =
It is set to 300 μm and S is set to 0.9 mm ² . Further, if air is clogged between the movable electrode portion 2 and the fixed drive electrode 3, ε = 8.85 × 10 ¹² , and if the potential difference V is 200 V, the generated force F in this case is F = 3.54 × 10 ^{− 6} [N] = 0.36 [mgf] (2) At this time, the weight of the movable film is about 1 μg and there is no problem in driving. The film is assumed to be polymer, glass, carbon fiber, metal foil, etc.
It is 100-10000 kg / mm ² , and as a result of the experiment, it was found that it can be sufficiently driven with the above-mentioned force.

Although the case where two fixed drive electrodes 3 are used has been described, the movable film can be attracted by only one of them, and at this time, the bending elasticity of the film itself is required to return the movable film. Harness the power.

Next, the function of the holding electrode 4 shown in FIG. 16 will be described. The display section 6 is black or colored and transparent as described above, and a transparent electrode is further coated on this. This is called a display electrode 37. Then, as shown in FIG. 16, the holding electrode and the display electrode form a capacitor through the insulating film and the gap. This is called a holding capacitor (Ch). When a potential difference is applied between the holding electrode 4 and the display electrode 37, the electrostatic attractive force as shown in the formula (1) works, and the movable film 1
Can be fixed. As will be described later, in the case of dot matrix display, the fixed drive electrode 3 cannot be fixed to a constant potential because it may be common with the signal line potential or the scanning line potential. Therefore, by keeping the holding electrode 4 at a constant potential, the movable film can be fixed regardless of the signal line potential or the scanning line potential. At this time, a DC voltage is applied to the capacitor Ch including the holding electrode 4 and the display electrode 37, and there is no power consumption in the steady state. This means that it has a memory function, and can achieve zero power consumption in the still image display state.

The holding electrode 4 also has a gradation control function. That is, as described above, since the display device produces gradation by the area gradation method, the movable film for moving the display unit must be stopped at a predetermined position. It is not possible to stop the display unit at a predetermined position only with the fixed drive electrode and the movable electrode portion of the movable film, that is, Cd. Here, it has been found from an experiment that the display unit can be moved by a predetermined gradation and stopped by controlling the timing of the voltage pulse applied to the driving capacitor Cd and the holding capacitor Ch. Since this gradation display function can control the display unit in an analog manner, full color display can be realized.

Further, as shown in FIG. 17, the transparent electrode 8 may be provided on the cover glass and the holding capacitor Ch may be formed between the transparent electrode 8 and the electrode on the white plate 5. In this case, it is not necessary to form electrodes on the display section 6.

Next, the material and manufacturing method of this display device will be described. As materials for the movable film 1, the fixed drive electrode 2, the white plate 5, and the display unit 6, polyester such as polyethylene terephthalate (PET), polyimide, nylon, polystyrene, polycarbonate, polymethylmethacrylate, polyethylene is used as an electrically insulating portion. , Polypropylene, polyether sulfone, polytetrafluoroethylene, polyphenyl sulfite, and other organic polymer films and their copolymers, or inorganic materials such as glass, carbon fiber, mica, silicon oxide, silicon nitride, and aluminum nitride. It is preferable in terms of workability, heat resistance and transparency. Conductive parts include aluminum, copper, gold, silver, nickel, chromium, iron, molybdenum,
A simple metal or an alloy of titanium, tungsten, tantalum or the like is preferable in terms of electric conductivity and workability. The main body of the movable film may be the electrically insulating material, the conductive material may be coated thereon, and the insulating material may be further coated. It may be coated with an insulating material.

For example, copper is vapor-deposited or sputtered to a thickness of about 10 nm to 1 μm on a PET film having a thickness of 12 μm, the metal in the portion corresponding to the display is removed by etching, and black opaque or cyan magenta yellow is used. The transparent ink is coated on the display unit 6 in the range of 100 nm to 10 μm, and this is used as the movable film 1.

It is also possible to coat the above-mentioned ink on the surface opposite to the surface coated with metal in advance, and pattern the ink before etching away the metal. Then, for example, when the pixel pitch is 300 μm, the film is cut into a width of about 290 μm and a length of about 6 mm, and
Plural pieces are arranged at a pitch of 00 μm and fixed with an adhesive tape. The electrodes on the movable film may be arranged with a conductive tape to electrically connect the electrodes to each other.

Next, the film near the display area is bent by about 90 degrees. To bend the film, put it in a mold and raise the temperature above the softening point of the film. Meanwhile, a method of manufacturing the above-mentioned fixed drive electrode will be described. Copper is deposited on a PET film having a thickness of 2 μm to a thickness of about 10 nm to 1 μm by vapor deposition or sputtering. This may be further coated with an insulating film. This film is cut into a tape with a width of 3 mm. Then, they are arranged at a pitch of 300 μm.

FIG. 18 shows an assembly diagram of this display device.
The movable film assembling member 28 having the fixed drive electrodes formed by arranging the movable films arranged in strips as described above is inserted between the fixed portion assembling members 24 in which a plurality of fixing portions are arranged. The movable film is electrically connected in the depth direction in the figure,
The end of the TAB-I is passed through the anisotropic conductive rubber 22.
Connect to C19. The connection of the movable film can be used as a scanning line. The fixed drive electrode 23 is connected to the signal line 25 on the base substrate 26 via the anisotropic conductive film 21, and 24 is a scanning line.
It is connected to the TAB-IC 19 via 2.

Adhesives may be attached to the bases of the movable film 1 and the fixed drive electrodes, which are the scanning lines 24 and the signal lines 25, and they may be attached to each other to prevent positional deviation. It is also possible to prepare a strong image frame and fix the end portion of the film to this to prevent the film from being displaced.

The display portion 6 of the movable film 1 can be projected from the gap of the white plate 5. Then, an electrode may be formed on the white plate 5 and used as the holding electrode 4. In this case, this electrode itself may be a scanning line as shown in FIG. 18 and may be connected to the TAB-IC 18. Further, although not absolutely necessary, in some cases, by attaching a cover glass 17 as a protective substrate and enclosing the movable film and the fixed drive electrode in an atmosphere of an inert gas such as nitrogen, electric charges are applied to the surface of the electrode. It is preferable because it can prevent dust from being attached.

By the way, there is a method shown in FIG. 19 as a method of arranging films such as the above-mentioned movable film and fixed drive electrode film. The roll-shaped film 27 has already been coated with a conductive material, patterned, and colored. A film cutter / film pasting machine 28 formed on the table 29 pulls the film by hand, cuts the film, and appropriately bends and sticks the film. Then, the display device is completed as shown at 30.
This method is excellent in mass productivity and contributes to the automated assembly of the display device.

Next, a method of driving the matrix display will be described. FIG. 20 shows a form in which the movable electrode portion 2 of the movable film 1 having the display portion 6 is connected to the signal line 33, and the two fixed drive electrodes 3 are connected to the scanning line 32. The signal line 33 can be set to a power supply voltage, a floating potential, or a ground potential, and can be controlled by a synchronization signal and a video signal input from the outside. Further, there are two scanning lines for one pixel, and their potentials can be a power supply voltage, a floating potential, and a ground potential, which can also be controlled by a synchronizing signal and a video signal input from the outside.

Next, a time chart of this matrix driving method will be described. For simplification, a display example of a 3 × 3 matrix shown in FIG. 21 will be described. The signal lines are called S _{1 to} S ₃ , the address lines are called A _{1 to} A _3, and their potentials are V _s1.
.About.V _s3, and there are two scanning lines per pixel, therefore, they are referred to as A _{L1 to} A _L3 and A _{R1 to} A _R3 for convenience, and their potentials are V _AL1 to V AL3.
_AL3 and V _{AR1 to} V _AR3 . These are shown in FIG. 22 as a one-pixel equivalent circuit.

In order to perform the display of FIG. 21, voltage is sequentially applied to the scanning lines / signal lines in the time chart of FIG. Since this structure does not have the holding capacitor Ch, the driving voltage signal must be continuously applied even when displaying a still image, but if the elastic coefficient of the movable film is sufficiently small, the position is held even when no voltage is applied. be able to.

In FIG. 24, the movable electrode section 2 of the movable film 1 having the display section 6 is connected to the scanning line 34, one of the two fixed drive electrodes 3 is connected to the signal line 33, and the other is connected to the scanning line 32. That is the case. Which scan line 34, signal line 33
Can be a power supply voltage, a floating potential, and a ground potential, and can be controlled by a synchronizing signal and a video signal input from the outside.

Next, a time chart of this matrix driving method will be described. For simplification, a display example of a 3 × 3 matrix shown in FIG. 25 will be described. The signal line is referred to as S ₁ to S _3, to the potential of the V _s1 ~V _s3. Since there are two scanning lines per pixel, for convenience, the one connected to the display unit is P
_{1 to} P ₃ , the other one is called A _{1 to} A _3, and its potential is V
Let _{P1 to} V _P3 and V _{A1 to} V _A3 . These are shown in FIG. 26 as a one-pixel equivalent circuit. In order to perform the display of FIG. 25, a voltage is sequentially applied to the scanning lines / signal lines in the time chart of FIG.

Since this structure does not have the holding capacitor Ch, the driving voltage signal must be continuously applied even when displaying a still image. However, if the elastic coefficient of the movable film is sufficiently small, its position is not applied. Can be held.

The matrix driving system shown in FIG. 28 has a holding capacitor Ch, which is connected to the scanning line 35. The movable electrode portion of the movable film 1 also has its own scanning line 34, and one of the fixed drive electrodes also has its own scanning line 32. The other fixed drive electrode is connected to the signal line 33. All of these signal lines / scanning lines can be set to a power supply voltage, a floating potential, and a ground potential. In particular, the scanning line of the holding capacitor Ch and the scanning line of the movable electrode portion can be set to a floating potential in a short-circuited state.

FIG. 30 shows a one-pixel equivalent circuit. The potentials of the scanning lines connected to the movable film are V _{P1 to} V _P3 , the potentials of the scanning lines connected to the holding electrodes are V _{H1 to} V _H3 , and the potentials of the scanning lines connected to the fixed drive electrode are V _A1 to V V. and _A3, the potential of the signal line and V _S1 ~V _S3.

FIG. 31 is a time chart of this matrix drive system, and shows the case of the 3 × 3 matrix display of FIG. 29 described above. Further, by not performing black writing and white writing at the same time, unnecessary charging is eliminated and power consumption is kept low.

Further, the scanning line and the signal line are characterized by being in a floating state when they are not selected, so that unnecessary capacitor charging is avoided and power consumption is reduced. The power consumption of this display device is zero when displaying a still image, and 640 even when displaying a moving image.
VGA size with × 480 pixels can achieve 0.5 W or less.

The display device of the present invention is of a reflective type. Since it has a high reflectance, it enables paper white display, has a wide color reproduction range in principle, is low in price, and is lightweight. Also, since it is a film substrate, it is possible to make as many large display devices as possible. Further, since it has a memory property in principle, it has an ability to hold an image even when the power supply is in an OFF state, and it does not flow a large current during driving, resulting in extremely low power consumption. This display device can be applied to portable information devices and personal computers that require low power consumption, as well as electronic books, electronic newspapers, electronic notebooks, electronic posters, signboards, console panels for control devices, and the like. Since this display device can display as vividly as gravure printing,
New applications other than the above are possible. The present invention is not limited to the above embodiment, but can be modified in various ways.

[0079]

As described above, according to the present invention,
A movable film type display device having high reflection brightness can be provided.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part of a movable film type display device according to an embodiment of the present invention.

FIG. 2 is a sectional view of an essential part of a movable film type display device according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view of a main part of a movable film type display device according to an embodiment of the present invention.

FIG. 4 is a perspective view of a main part of a movable film type display device according to an embodiment of the present invention.

FIG. 5 is a perspective view of a movable film according to an embodiment of the present invention.

FIG. 6 is a perspective view of a movable film according to an embodiment of the present invention.

FIG. 7 is a sectional view of a movable film according to an embodiment of the present invention.

FIG. 8 is a sectional view of a movable film according to an embodiment of the present invention.

FIG. 9 is a sectional view of a movable film according to an embodiment of the present invention.

FIG. 10 is a sectional view of a movable film according to an embodiment of the present invention.

FIG. 11 is a sectional view of a movable film according to an embodiment of the present invention.

FIG. 12 is a sectional view of a movable film according to an embodiment of the present invention.

FIG. 13 is a sectional view of a movable film according to an example of the present invention.

FIG. 14 is a sectional view of a movable film according to an embodiment of the present invention.

FIG. 15 is a sectional view of a movable film according to an embodiment of the present invention.

FIG. 16 is a sectional view of a movable film according to an embodiment of the present invention.

FIG. 17 is a sectional view of a movable film according to an example of the present invention.

FIG. 18 is an exploded view of a movable film type display device according to an embodiment of the present invention.

FIG. 19 is a method for manufacturing a movable film type display device according to an embodiment of the present invention.

FIG. 20 is a circuit diagram when the display device of the embodiment of the present invention is displayed in matrix.

FIG. 21 is an explanatory diagram of a movable film type display device according to an embodiment of the present invention.

FIG. 22 is an explanatory diagram of a movable film type display device according to an embodiment of the present invention.

FIG. 23 is an explanatory diagram of a movable film type display device according to an embodiment of the present invention.

FIG. 24 is a circuit diagram of a movable film type display device according to an embodiment of the present invention.

FIG. 25 is an explanatory diagram of a movable film type display device according to an embodiment of the present invention.

FIG. 26 is a circuit diagram of a movable film type display device according to an embodiment of the present invention.

FIG. 27 is a time chart of a movable film type display device according to an example of the present invention.

FIG. 28 is a circuit diagram of a movable film type display device according to an example of the present invention.

FIG. 29 is an explanatory diagram of a movable film type display device according to an example of the present invention.

FIG. 30 is a circuit diagram of a movable film type display device according to an embodiment of the present invention.

FIG. 31 is a time chart of a movable film type display device according to an example of the present invention.

FIG. 32 is a cross-sectional view of a conventional display device using electrostatic force.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Movable film 2 ... Movable electrode part 3 ... Fixed drive electrode 4 ... Holding electrode 5 ... White plate 6 ... Display part 7 ... Bimorph type piezoelectric film 8 ... Transparent electrode-attached cover glass 9 ... Insulating film 10 ... Transparent electrode 11 ... Electret 12 ... Polyimide film 13 ... Polyester film 14 ... Display part (cyan) 15 ... Display part (magenta) 16 ... Display part (yellow) 17 ... Cover glass 18 ... TAB-IC (for holding electrode) 19 ... TAB-IC (scanning) Wire) 20 ... TAB-IC (for signal wire) 21 ... ACF (anisotropic conductive film) 22 ... ACF (anisotropic conductive film) silicon rubber pressure bonding type 23 ... Fixed drive electrode (for signal wire) 24 ... Fixed Drive electrode (for scanning line) 25 ... Signal line 26 ... Base substrate 27 ... Roll film 28 ... Film cutter / film attachment 29 ... Manufacturing apparatus stage 30 ... Main display device during manufacturing 31 ... Holding jig 32 ... Scan line (for fixed drive electrode) 33 ... Signal line 34 ... Scan line (for movable electrode) 35 ... Scan line (for holding electrode) 36 ... Pixel area 37 ... Display electrode

Claims (15)

[Claims] 1. A fixed part of a first color, a movable film which is exposed or hidden from the fixed part to allow the second color to be taken in and out, and the movable film which is at least perpendicular to the surface of the movable film. A support capable of supporting
A movable film type display device comprising: a drive unit capable of exposing or concealing the movable film from the fixed portion by bending the support with an electrostatic force. 2. A fixed part of a first color, a movable film which is exposed or hidden from the fixed part to allow the second color to be taken in and out, and the movable film which is at least perpendicular to the surface of the movable film. A support capable of supporting
A movable film type display device comprising: a bimorph type piezoelectric film formed on the support and capable of exposing or hiding the movable film from the fixed portion by bending due to distortion of the piezoelectric film. 3. The driving device according to claim 1, further comprising another driving means capable of stopping the bending movement of the movable film at an arbitrary position by applying an electrostatic force. Movable film type display device. 4. A transparent plate for protection on the movable film,
And a transparent electrode formed on the surface of the transparent plate and capable of stopping the bending motion of the movable film at an arbitrary position by applying an electrostatic force between the movable plate and the fixed portion. The movable film type display device according to claim 1 or 2. 5. The movable film type display device according to claim 1, wherein the movable film is housed under the fixed portion. 6. The movable film type display device according to claim 1, wherein the fixed portion is a white opaque film, and the movable film is a black opaque film. 7. The method according to claim 1, wherein the fixed portion is a white opaque film, and the movable film is a three-layer transparent film which is colored cyan, magenta, and yellow and which can be moved independently. Item 3. A movable film type display device according to item 2. 8. The movable film type display device according to claim 7, wherein the movable film is a four-layer structure in which a black opaque film is added in addition to the three colors of cyan, magenta and yellow. . 9. A movable film having a fixed portion of a first color, and a second color which is exposed or hidden from the fixed portion and which allows the second color to be taken in and out; A support capable of supporting
A pixel having drive means capable of exposing or concealing the movable film from the fixed portion by bending the support with an electrostatic force, and the pixels are arranged in a plane in a matrix. Movable film type display device. 10. The movable film type display device according to claim 9, wherein an electrostatic force applied to bend the movable film is formed by two electrodes sandwiching the movable film. 11. A first wiring for transmitting an electric charge to the movable film is provided, the first wiring is connected to a signal line for transmitting image information, and an electrostatic force applied to bend the movable film is applied. A dot matrix display is possible, characterized in that the two electrodes to be generated are connected to respective wirings for applying electric charges to them, and these wirings are scanning lines for selecting pixels to which image information is to be transmitted. Item 10. A movable film type display device according to item 10. 12. The movable film type display device according to claim 9, wherein one of the wirings functions as a scanning line and the other is connected to a signal line, which enables a dot matrix display. 13. A first wiring for transmitting electric charges to the movable film is provided, and the first wiring serves as a scanning line, and an electrostatic force is generated to stop the movement of the display area of the movable film. There is an electrode and a second wire for supplying electric charge to the electrode, the second wire is also a scanning line, and two electrodes for generating an electrostatic force to bend the movable film charge them. 10. The movable film type display according to claim 9, wherein dot matrix display is possible, characterized in that one of them is a scanning line and the other is connected to a signal line. apparatus. 14. A movable film type display device capable of dot matrix display according to claim 10, 11, 12 or 13, wherein the potential of the signal line and the potential of the scanning line can be set to a floating potential. 15. A fixed part assembly member in which a plurality of fixed parts of a first color are connected, and a movable film assembly member in which a plurality of movable films which are exposed or hidden from the fixed part and which allow the second color to be taken in and out are connected. A movable film type display device comprising: a step of preparing and a step of arranging the fixed portion collective member and the movable film collective member on the base substrate in an alternating manner and disposing a protective substrate from above. Manufacturing method.