JPH1195693A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin type display device having a large screen, inexpensiveness, a high luminance, and a low power consumption together. SOLUTION: A large screen display is formed by arraying in row and column directions plural display units, each of which is a column array of plural picture elements comprising a transparent light guide body fixed electrode part 10 which are composed of a transparent material formed long in the column direction, which have a transparent conductive layer on the surface part emitting light which is incident from the outside, and which are plurally arrayed in the row direction, and movable film electrodes 22a-22e which are plurally arrayed in the direction of row facing the transparent conductive layer to each of those transparent light guide body fixing electrodes 10 and very centering on the fulcrum according to an electrostatic force working to these transparent conductive layers. And, the transparent conductive layers of the picture element units adjacent to each other along the row direction are electrically connected by the transparent conductive body 55 formed on the transparent light guide fixed electrode part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a display device for performing display using electrostatic force.

[0002]

2. Description of the Related Art At present, a large-sized image display device is receiving attention. FIG. 38 shows an outline of a conventional large display device. The extensibility indicates an evaluation when a large screen is formed by connecting small displays.

[0003] Each display will be described. C
Although the RT (CRT) is the most widespread display device, it is technically difficult to produce a thin and large display device of 40 inches or more. Further, since the weight becomes considerably heavy, it becomes difficult to handle. There is also a technique in which small CRTs are connected, but it is difficult to completely eliminate the connection.

[0004] The plasma display (PDP) is 40
It has attracted the most attention as an inch-size thin display, but it has problems that the maximum brightness is below the CRT, the power consumption is large, the manufacturing cost is high, and it is difficult to make it 10,000 yen per inch. I have.

[0005] In addition, there is a problem that the production cost is more than doubled when trying to make a larger display. This is because the production line is constructed according to the display size that is considered to be the most popular. Also, if a 40-inch or larger product is made by joining, the PDP is a low-pressure gas-filled type, so the peripheral wall cannot be reduced in any way, and the joining becomes conspicuous.

[0006] PALC (Plasma Addressing Liquid Crystal) is a combination of a liquid crystal cell and a plasma generating electrode. That is, a cell for plasma generation is formed separately from the liquid crystal cell, and the two cells are overlapped. The plasma cell has a function of selecting which pixel in the liquid crystal cell is applied with a potential. It is said that a large-area display can be performed at a lower cost than a selection method using a conventional TFT (thin film transistor). However, since this display is also configured on a production line according to a specific size (for example, 40 inches) like a PDP, as the display size is increased, the price rises sharply. Also, in the case of joining, the joint becomes conspicuous as in PDP.

In the case of a liquid crystal display (LCD), the maximum size is currently 20 inches, and at present, the maximum size is 30 inches even if a bonding technique is used. Also,
If a large area is used because a TFT is used, the price increases.

The FED (field emission display) is a system in which minute cold cathodes for emitting electrons are arranged on a silicon substrate or a glass substrate, and electrons emitted from the cold cathodes are applied to a fluorescent substance to display. . Although it is said that this method can provide the maximum luminance comparable to that of a CRT, it is difficult to form a uniform cold cathode on a large-area substrate, and it is difficult to form a large-screen display.

An LED (Light Emitting Diode) is a large display in which a number of light emitting diodes are arranged. It is the most widespread as a large thin display of 40 inches or more. However, power consumption is high and the price is high. Since the light emitting diode is used, the maximum luminance is not so large.

That is, the conventional thin large-sized display has a problem that there is no inexpensive display having high expandability.

Further, there is a movable film type display device in which an electric field is applied to a plastic foil, a metal foil or the like to move the same, and the display functions as a shutter (Japanese Patent Laid-Open No. 1-19219).
5, JP-A-1-72196, JP-A-1-10859
No. 8 and JP-A-4-123391).

In this apparatus, a light source such as an LED or a light bulb is placed inside a cylinder having a transparent electrode coated on its surface, and a conductive movable film is installed so as to cover the cylinder. Then, by giving a potential difference between the cylinder and the movable film, the movable film is displaced to change the amount of light emitted from the cylinder.

It is considered that an inexpensive thin display device can be formed by using this display method. However, conventionally, there has been no specific method for forming a large display using a movable film type display device.

[0014]

As described above, conventionally, there has been a problem that there is no inexpensive thin display device having a large screen. In addition, a movable film type display device can be manufactured at low cost, but there is no technology for forming a large screen.

A first object of the present invention is to provide a display device which enables a large-screen display in a movable film type display device and can be manufactured at low cost.

A second object of the present invention is to provide a movable film type display device excellent in gradation display in addition to the above.

[0017]

In order to solve the above-mentioned problems, a display device according to a first aspect of the present invention (claim 1) is made of a transparent material, and transmits light incident from the outside to a transparent conductive layer. A light guide fixed electrode portion that guides light to the surface portion having the light, and faces the transparent conductive layer of the light guide fixed electrode portion,
A flexible conductive light-shielding plate, one end of which is fixed so as to allow the emitted light to pass therethrough, and a potential difference between the conductive light-shielding plate and the transparent conductive layer is given to the transparent conductive layer. And an electrostatic force generating means for generating an electrostatic force between the conductive light-shielding plate and the conductive light-shielding plate, wherein when the potential difference is applied to the conductive light-shielding plate and the transparent conductive layer, the conductive light-shielding plate is And displacing the one end as an axis in response to the electrostatic force to shield the surface of the light guide fixing electrode.

The conductive light-shielding plates are arranged in rows and columns to form a plurality of conductive light-shielding plates, and the light guide fixed electrode section includes a plurality of transparent conductive layers arranged in the rows and columns. Forming a plurality of light guide fixed electrode portions each having a transparent conductive layer, the electrostatic force generating means, between each of the plurality of conductive light shielding plates and a corresponding one of the plurality of transparent conductive layers, Means for providing an independent potential difference may be included (claim 2).

It is desirable that the plurality of light guide fixing electrodes arranged in the same row are formed integrally (claim 3).

It is preferable that the plurality of transparent conductive layers of the plurality of transparent light guide fixed electrode portions arranged in the same row direction are electrically connected to each other.

It is desirable that the surface of the transparent light guide fixing electrode is curved.

Preferably, a light-shielding frame is formed around the transparent conductive layer of the light guide fixing electrode portion.

According to the display device of the first aspect of the present invention,
The conductive light-shielding plate is displaced about the fulcrum by an electrostatic force generated when a potential difference is applied between the conductive light-shielding plate and the transparent conductive layer.
The area where the conductive light-shielding plate covers the transparent conductive layer changes according to the amount of displacement of the conductive light-shielding plate. Therefore, by controlling the area where the conductive light-shielding plate covers the transparent conductive layer, that is, by controlling the electrostatic force acting between the conductive light-shielding plate and the transparent conductive layer, the amount of light emitted from the transparent conductive layer changes, Desired gradation display can be performed.

Further, since the present apparatus can be manufactured using inexpensive members, the cost can be reduced.

Also, since a multi-color display is performed using color filters, the color reproduction range is wide. The present device has a wider color reproduction range than PDPs and FEDs that display using phosphors.

Further, since a polarizing plate is not used unlike the LCD, the light use efficiency is about 2.5 times higher than that of the LCD, so that it is possible to reduce the power consumption and increase the brightness.

In the present invention, the screen size can be freely set by arranging a plurality of basic display units in a matrix. At this time, a large-sized display device can be provided more easily and inexpensively by electrically connecting the transparent conductive layers also serving as adjacent scanning lines.

When a large screen display device is formed by combining display units, the joints are not visually recognized because the pixel pitch is coarse.

Further, by making the surface of the transparent conductive layer facing the conductive light-shielding plate curved, it is easy to control the area where the conductive light-shielding plate covers the transparent conductive layer, thereby facilitating gradation display.

Further, by forming a black matrix, light leakage from peripheral pixels can be suppressed, and display characteristics can be improved.

A display device according to a second aspect of the present invention (claim 7) is arranged so as to form a plurality of plate-like fixed electrodes, a plurality of fixed electrodes, and a light passage portion. In addition, a plurality of optical shutter units each including a plurality of light-shielding cantilever-shaped movable film electrodes, and selectively statically moving between each of the plurality of fixed electrodes and a corresponding one of the plurality of movable electrodes. Power generation means for selectively bending the plurality of movable electrodes to selectively block the light passage portion of the plurality of optical shutter units, wherein the plurality of optical shutters The unit forms a plurality of optical shutter sets each including an arbitrary number of optical shutter units adjacent to each other, and in each of the plurality of optical shutter sets, the plurality of fixed electrodes are electrically connected to each other. The plurality of movable electrodes are electrically connected to each other, and the electrostatic force generating means simultaneously applies an electrostatic force between each of the plurality of fixed electrodes and a corresponding one of the plurality of movable electrodes. By causing the plurality of shutter sets, the light passing portions of the plurality of adjacent light shutter units are simultaneously shielded, and the electrostatic force generation means selectively generates the electrostatic force on the plurality of shutter sets, thereby forming the plurality of shutter sets. Is selectively closed.

In the display device according to a second aspect of the present invention, the plurality of optical shutter sets constitute a plurality of optical shutter groups each including an arbitrary number of optical shutter sets adjacent to each other, and In each of the shutter groups, the plurality of shutter sets are selectively closed by the electrostatic force generating means (claim 8).

[0033] In each of the plurality of shutter groups, the amount of the light passing through the shutter group can be controlled by the number of the plurality of shutter sets to be closed (claim 9).

[0034] Further, the sizes of the plurality of shutter sets included in each of the plurality of shutter groups are set to be different from each other, and the plurality of shutter sets are selectively closed. The amount of the light passing through the group can be controlled (claim 10).

It is preferable that a ratio of the light passing amount of the plurality of shutter sets included in each of the plurality of shutter groups to a minimum value thereof is a ratio of an integer power of 2. Item 11).

[0036] The plurality of shutter groups can constitute a plurality of pixels capable of dither gradation.

According to the second aspect of the present invention, the opening / closing time can be shortened by simultaneously opening / closing a pixel (or a sub-pixel) formed by a plurality of shutter units.

Further, eight sub-pixels are provided in one pixel, and their area ratio is, for example, 1: 2: 4: 8: 16: 3.
If the ratio is 2: 64: 128, 256 kinds of gradations can be displayed by a combination of these sub-pixels. Even a sub-pixel having a large area is composed of a plurality of shutter units, and the swing width of each movable electrode can be 100 μm or less. As a result, writing for 60 μsec becomes possible, and moving images can be handled.

A display device according to a third aspect of the present invention (claim 1)
3) A cantilever-shaped movable film electrode having one end fixed and a light-shielding movable film electrode, and a first and a second electrode which are opposed to the movable electrode, and which are arranged insulated so as to sandwich the movable electrode from both sides. A second fixed electrode, wherein the first fixed electrode has a portion separated from the movable electrode to form a light passage, and the first and second fixed electrodes; A first insulating material interposed between the first fixed electrode, a second insulating material interposed between the movable electrode and the second fixed electrode, and the first fixed electrode A first voltage source that supplies a desired voltage to the second fixed electrode, a second voltage source that supplies a desired voltage to the second fixed electrode, and a third voltage source that supplies a desired voltage to the movable electrode. When a potential difference is given between the movable electrode and the first fixed electrode, by electrostatic force, The movable electrode is attracted to the first fixed electrode to block the light, and when a potential difference is given between the movable electrode and the second fixed electrode, the movable electrode When the potential difference between the first fixed electrode and the movable electrode is gradually increased by being attracted to the second fixed electrode and passing the light, the movable electrode When the potential that reaches the first electrode for the first time via the insulating material is V1, the third voltage source supplies the movable electrode with a voltage obtained by adding a predetermined margin voltage V2 to V1. The first voltage source supplies one of a voltage obtained by adding V2 to V1 and a ground voltage to the first fixed electrode, and the second voltage source supplies a voltage obtained by adding V2 to V1. And the other of the ground voltage to the second fixed electrode The movable electrode approaches the larger of the potential difference with the first fixed electrode and the potential difference with the second fixed electrode, based on the difference in the electrostatic force, and opens and closes the passage of the light. It is characterized by doing.

The second fixed electrode has a structure symmetrical to the first fixed electrode with respect to the movable electrode, and gradually increases the potential difference between the second electrode and the movable electrode. In this case, the potential at which the movable electrode first reaches the second electrode via the second insulating material is the first potential.
It is desirable that V1 is substantially the same as that of the fixed electrode (claim 14).

In a display device according to a third aspect, a plurality of optical shutters each including the movable electrode and the first and second fixed electrodes are arranged in a matrix, and are arranged for each of the columns. A plurality of signal lines each connected to the movable electrode of each of the corresponding plurality of optical shutters,
A plurality of first scanning lines arranged for each row, each of which is connected to the first fixed electrode of each of the plurality of optical shutters, and a plurality of first scanning lines arranged for each row, each of which corresponds to It is preferable that a plurality of optical shutters be provided with a plurality of second scanning lines connected to the second fixed electrode.

When the potential difference between the movable electrode and one of the first and second fixed electrodes is gradually reduced from V1, the movable film electrode becomes the first and second fixed electrodes. A potential first separated from any one of the second fixed electrodes is V3, which is higher than V3,
When the potential lower than V1 is V4, the state in which the movable electrode is attracted to the one of the first and second fixed electrodes corresponds to the potential of the first and second fixed electrodes. It is held by setting it to V4 (claim 16).

The plurality of first scanning lines are divided into a plurality of groups of k (k is an integer of 2 or more) lines, and k first lines included in an arbitrary one of the plurality of groups. Scan lines have switching functions of connecting k first reference potential lines to the k reference potential lines and connecting the first scan line to the ground line, respectively.
Are electrically connected to each other via a changeover switch, and the plurality of second scanning lines are divided into groups of k lines corresponding to the plurality of first scanning lines. And k second scanning lines included in one of the first and second switching switches each having a switching function of connecting the second scanning line to a ground line to k second reference potential lines. (Embodiment 17).

The k first scanning lines included in an arbitrary one of the plurality of groups each apply an arbitrary potential higher than the ground potential and lower than the V1 through the switch. And the k second scanning lines respectively connected to the k first reference potential lines and corresponding to the k first scanning lines have a potential of V1 + V2. 2 of the plurality of signal lines, and a selected one of the plurality of signal lines is included in the arbitrary one of the plurality of groups according to a time that is maintained at a potential of V1 + V2. The plurality of optical shutters can selectively block the light (claim 18).

The k second scanning lines included in an arbitrary one of the plurality of groups each apply an arbitrary potential higher than the ground potential and lower than the V1 through the switch. K first reference lines connected to the k second reference potential lines and corresponding to the k second scanning lines.
Scan lines have a potential of V1 + V2, respectively.
One of the plurality of signal lines connected to the first reference potential line, and a selected one of the plurality of signal lines is connected to the arbitrary one of the plurality of groups in accordance with a time during which the signal line is held at a potential of V1 + V2. The light can be selectively passed through the plurality of included light shutters (claim 19).

In the plurality of optical shutters included in an arbitrary one of the plurality of groups, a potential difference between the movable electrode and the second fixed electrode and a potential difference between the plurality of signal lines are determined. When the product of the time during which the selected signal line is held at the potential of V1 + V2 becomes a predetermined value or more, the movable electrode is drawn to the first fixed electrode, and the light is blocked. (Claim 20).

The plurality of optical shutters included in the arbitrary one of the plurality of groups according to the time during which a selected one of the plurality of signal lines is held at the potential of V1 + V2. The amount of the light passing through is changed (claim 21).

[0048] Among the plurality of optical shutters included in an arbitrary one of the plurality of groups, among the plurality of optical shutters connected to a selected one of the plurality of signal lines. Only when the potential difference between the movable electrode and the first fixed electrode is greater than or equal to a predetermined potential difference, the light can pass therethrough (claim 22).

According to the third aspect of the present invention, since the predetermined potential is applied to the signal line even in the holding state, the voltage amplitude of the signal line is minimized and the power consumption of the movable film type display device is reduced. Can be realized.

One pixel is constituted by a plurality of scanning lines and a plurality of signal lines, and the potentials of the plurality of scanning lines constituting the one pixel are different from each other, and one signal line is simultaneously applied to the plurality of scanning lines. The sub-pixels (scanning lines) to be written and the sub-pixels (scanning lines) not to be written appear in accordance with the time when the potential of the pixel becomes the writing potential. If the writing time of a plurality of signal lines constituting one pixel is changed, sub-pixels to be written and sub-pixels not to be written are two-dimensionally selected, thereby enabling halftone display by dither gradation.

Further, since the size of the shutter unit constituting one pixel (sub-pixel) is about 50 μm × 50 μm, if the driving of the scanning line is switched to the same line sequential scanning as the conventional one, a high definition image display is achieved. Can also be done.

As a result, it is possible to provide a movable film type display device capable of displaying both a high definition image quality and a halftone moving image which are required of the display device.

[0053]

Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment] First, a configuration of a pixel which characterizes the movable film type display device of the present embodiment will be described.

FIG. 1 is a diagram showing a configuration for one pixel of a movable film type display device according to a first embodiment of the present invention.

First, the overall structure of one pixel will be described with reference to the perspective view of FIG. Reflecting plates 21 made of a matte aluminum plate or a silver plate, a white plate having a high reflectance, or the like are provided on two surfaces facing the curved surface of the transparent light guide fixed electrode unit 10.
(21a, 21b) are formed. Further, a movable film shutter (conductive light-shielding plate) 22 having light-shielding properties, elasticity, and conductivity is provided to face the curved surface of the transparent light guide fixed electrode section 10. Movable film shutter 2
2 is made of a material such as PET (polyethylene terephthalate) on which a conductive material such as aluminum or silver is deposited, or a metal foil such as nickel or aluminum.

Incidentally, the transparent light guide fixed electrode section 10 is the same as that shown in FIG.
As shown in the cross-sectional view of (b), a transparent light guide 11 made of acrylic resin or polycarbonate and the like are formed on the curved surface of the transparent light guide 11 and made of ITO (indium tin oxide) or the like. Transparent conductive layer 12 and transparent conductive layer 12
It comprises a transparent insulating layer 13 formed thereon to prevent a short circuit with the movable film shutter, and a black matrix 14 formed on the transparent insulating layer 13 to divide one pixel. The black matrix 14
Is formed, for example, by applying a light-shielding ink. Further, the transparent conductive layer 12 has an opening 15 in which the black matrix 14 is not covered.

The light incident from the side of the transparent light guide 11 is
Light is emitted from the opening 15 via the transparent light guide 11, the transparent conductive layer 12, and the transparent insulating layer 13. The movable film type display device according to the present embodiment includes a movable film electrode 2
2 is bent to change the area where the movable film electrode 22 covers the opening 15, thereby changing the amount of light emitted from the opening 15 and displaying a gradation.

The principle of displacement of the movable film electrode 22 will be described with reference to FIG. In the circuit diagram of FIG. 2A, the circuit is composed of a capacitor composed of two electrode plates 31, 32, a switch 33, and a battery.

The switch 33 is turned on, and the two electrodes 31,
When a voltage is applied from a battery 34 between the electrodes 32, an electrostatic force acts between the electrodes, and the two electrodes 31, 32 attract each other.

In the configuration of the present embodiment, FIG.
As shown in (b), a curved fixed electrode (transparent conductive layer)
35 and a movable electrode (movable film electrode) made of an elastic body
36. Note that an insulating film (not shown) must be interposed between the electrodes. And switch 3
When 3 is turned on and a voltage is applied to the two electrodes 35 and 36, an electrostatic force acts between the two electrodes 35 and 36. Then
The movable electrode 36 made of an elastic body can be bent toward the fixed electrode 35. The amount of deflection of the movable electrode 36 can be controlled by the magnitude of the electrostatic force, that is, the potential difference between the electrodes. Then, if the switch 33 is turned off to eliminate the potential difference between the two electrodes 35 and 36, the electrodes return to the original position by the elastic force of the movable electrode 36 itself.

That is, in the present apparatus, the amount of bending of the movable film electrode 22 is changed by controlling the potential difference between the transparent conductive layer 12 and the movable film electrode 22, and the movable film electrode 22 closes the opening 15. The area covered is controlled.

As shown in FIG. 2C, it is also possible to provide curved fixed electrodes 35 and 37 on both sides of the movable electrode 36. By appropriately selecting the switches 33a and 33b and changing the direction of the electric field, the electrostatic force can be applied from both directions, so that the elastic force of the electrode itself is weak.
Or can be used when there is none.

Next, the overall structure of the movable film type display device will be described with reference to FIGS. FIG. 3 is a plan view showing the configuration of the movable film type display device according to the first embodiment of the present invention. FIG. 4 is a sectional view showing the configuration of the movable film type display device of FIG. FIG. 4A shows AA ′
FIG. 4B is a cross-sectional view taken along the line BB ′.

The display section 40 of the present device is composed of display units 41 (41a to 41d) in which the pixels shown in FIG. 1 are arranged in a matrix. And
Fluorescent lamps 42 are provided on opposite sides of the display unit 40, respectively.
Is installed. Each display unit 4
The drive circuits 43 (43a to 43d) are connected to 1 respectively. Then, the display unit 41 (4
1a to 41d), color filters 4
4 (44a to 44d) are arranged to face each other.

The number of pixels of the display unit 41 is approximately 100 × 100, and the size is about 10 cm square.

The size of a large display device having a size of 40 inches or more will be described below. The size of a pixel (for three pixels in FIG. 1) for performing color tone display is relatively large, and is about 1 mm square. Accordingly, the size of one pixel has a width W of about 1 mm and a depth D of about 0.33 mm for convenience of arranging RGB of the three primary colors. The length L is 1 to
4 mm, and the thickness of the movable film electrode 22 is 3 to 12 microns. There is a trade-off between the length and the thickness of the movable film electrode 22, and if the applied electrostatic force is constant, the longer the thickness, the longer the length.

Next, a display method of the present apparatus will be briefly described. The light emitted from the fluorescent lamp 42 passes through the transparent light guide fixed electrode unit 10, the amount of transmission is controlled by the movable film electrode 22, and the transmitted light is colored when passing through the color filter 44. The movable film electrode 22 is
The movement is controlled by 3a to 43d.

The display unit 41 is the same as that shown in FIG.
Are arranged in a row direction so that the pixels are arranged in a matrix. The configuration of the pixel unit will be described with reference to the perspective view of FIG. One transparent light guide fixed electrode section 10
In contrast, a plurality of movable film electrodes 22a to 22e are arranged to face each other. A circuit board 51 is provided adjacent to the transparent light guide fixed electrode section 10, and a driving I
C52 is installed. Movable film electrodes 22a-2
2e is connected to the driving IC 52 via the wiring 53. Further, the circuit board 51 is provided with a connector section 54, and can exchange information with an adjacent display unit.

A transparent conductor portion 55 having elasticity and being electrically connected to the transparent conductive layer is formed on the side surface of the transparent light guide fixed electrode portion 10. When a display unit is configured, the transparent conductive layers of adjacent display units are electrically connected by the conductive portion 55. The transparent conductor 55 is formed by coating a transparent and elastic material such as silicon rubber with a transparent conductive film such as ITO. By forming the transparent conductor portion 55 with an elastic body, the adjacent transparent light guide solid electrode portion 10 is formed.
By pressing from both sides, poor contact can be prevented.

Next, a driving method of the present apparatus will be described. FIG. 6 shows a circuit diagram of the present display device. In the present device, the transparent conductive layer 12 of the transparent light guide fixed electrode portion serves as a scanning line. The video information sent from the signal source 61 is once stored in the driving IC 52 and is
Is transmitted as a potential. If a potential is appropriately applied to the transparent conductive layer 12 from the driving IC 52, there is a potential difference with the movable film electrode 22, and the movable film electrode 22 can be bent toward the transparent conductive layer 12. If the movable film electrode 22 and the transparent conductive layer 12 have the same potential, no attractive force acts between the movable film electrode 22 and the transparent conductive layer 12, and the elastic force of the movable film electrode 22 causes
The movable film electrode 22 and the transparent light guide electrode 11 are separated.

In the case of this circuit, the movable film electrode 22 for each pixel and the noise IC 52 are directly connected, and the signal source 6
1 to a potential corresponding to the information stored in the memory (latch circuit) in the driving IC 52.
2, the electrostatic force between the transparent conductive layer 12 and the movable film electrode 22 is controlled, and the amount by which the movable film electrode 22 closes the opening of the transparent light guide fixed electrode portion is controlled.

The potential of the transparent conductive layer 12 is controlled by the scanning line driving IC 62, and is sequentially supplied with a potential by a built-in shift register.

It is also possible to always display a constant potential on all the transparent conductive layers (scanning lines) 12 and to simultaneously apply a potential corresponding to a signal to each movable film electrode to perform display.

The voltage applied to the movable film electrode is 10 to 200 V, and the power consumption is low. The driving IC 52 is a driver IC for a simple matrix.
Or an IC for plasma display or the like.

However, in the case of the circuit described above, it is necessary to provide the driving IC 52 for each scanning line, so that the number of driving ICs increases and the cost increases. Therefore, in order to reduce the price, as shown in FIG.
By providing the signal lines 71 and the signal lines 72, the video information is continuously supplied to all the signal lines, and the scanning line driving IC 62 appropriately applies a potential to the transparent conductive layer (scanning line) 12, so that the video information can be selected. You can also do so.

In addition to the transparent electrode 12, the fixed electrode is
As shown in the circuit diagram of FIG. 8, a fixed electrode 81 corresponding to the fixed electrode 37 of FIG. 2C may be provided. The movable film electrode 22 is connected to a signal line 86 arranged in a column direction, and the transparent conductive layer 12 and the fixed electrode 81 are connected to scanning lines 82 and 83 arranged in a row direction. The end of the signal line 86 is connected to a potential switch 87
Is connected to the power supply 88 via the. Also, the scanning line 8
2 and 83 are also connected to the potential change switch 8 respectively.
The power supply 88 is connected to the power supply 88 via the terminals 4 and 85. The potentials of these wirings and electrodes can take three potentials, 0, v, and 2v.

The driving method will be described with reference to FIG.
FIG. 9A is a timing chart showing the potential of each electrode, and FIG. 9B is a diagram showing the position of the movable film electrode. In FIG. 9A, A is the potential of the fixed electrode 81, B is
Indicates the potential of the transparent conductive layer 12, C indicates the potential of the movable film electrode 22, H on the time axis indicates a holding state, and S indicates a selected state. In FIG. 9B, H indicates the position of the movable film electrode 22 in the holding state, and S indicates the position of the movable film electrode 22 in the selected state.

In the holding state, the potential of the transparent conductive layer 12 and the potential of the fixed electrode 81 are the same, and the movable film electrode 22
Is a state of approaching the closer electrode regardless of the potential. The selected state means that the transparent conductive layer 12 and the fixed electrode 8
In this state, the potential of the movable film electrode 22 is different from that of the movable film electrode 22 depending on the potential.

The potential state of each pixel repeats the holding state and the selection state. The fixed electrode 81 has a potential of 0 in the holding state and a potential of 2 V in the selected state. Transparent conductive layer 12
Is a potential 0 when in the holding state and takes a potential v when in the selected state. The potential of the movable film electrode 22 can be any potential in the holding state, but when the potential is 2v in the selected state, the movable film electrode 22 moves toward the fixed electrode 81,
When the electric potential v is taken, it moves toward the transparent conductive layer 12. In this way, arbitrary image information can be written to each pixel.

When there are two fixed electrodes, as described above, the movable film electrode does not need to have elasticity, and furthermore, the surface on which the transparent conductive layer is formed, that is, the surface from which light is emitted. However, it may be constituted by a plane.

The display of the apparatus shown in FIGS. 3 and 4 will be further described with reference to FIGS. FIG.
FIG. 1 is a perspective view showing a configuration of a movable film type display device.
FIG. 11 is a plan view showing a configuration of a movable film type display device,
FIG. 11B is a cross-sectional view.

The light from the fluorescent lamp 42 enters the transparent light guide fixing electrode 10 and is reflected by the reflection plate 21 so that the opening 15
Are output to the front of the display device, are colored by a color filter, and are output. However, the movable film electrode 2
If 2 hides the opening 15, no light is output.
Although not shown in FIGS. 10 and 11 as a composite of display units, a large display can be created by using a composite of a plurality of display units as shown in FIGS.

As can be seen from FIG. 11A, since the circuit board 51 is installed on the back side of the reflection plate 21b,
Space utilization efficiency can be increased.

According to the present embodiment, since the transparent light guide can be manufactured by injection molding, and the movable film electrode can use a PET film for a capacitor, the display unit can be manufactured at low cost. Therefore, the entire display can be manufactured at low cost.

Since the pixel pitch of the color filter of the present apparatus is rough, it is not necessary to perform precision printing on a glass substrate unlike the color filter of LCD or PDP. Therefore, the color filters of the present apparatus can be formed with a precision of a simple printing level, and the present apparatus can use very inexpensive color filters.

Further, since the pixel pitch is coarse, the joint when the display units are joined cannot be almost visually recognized.

[Second Embodiment] FIG. 12 shows a second embodiment of the present invention.
It is a perspective view showing the composition of the movable film type display concerning an embodiment. FIG. 13 is a diagram showing a configuration of a movable film type display device according to the second embodiment of the present invention. FIG. 13A is a sectional view of a movable film type display device, and FIG.
(B) is a plan view.

The feature of this embodiment is that the reflector 21b on the bottom surface of the transparent light guide fixed electrode portion 10 shown in FIG.
That is, light is incident from the surface where 1b is formed. That is, as shown in FIG. 13, the fluorescent lamp 91 is installed on the bottom surface side of the transparent light guide fixed electrode unit 10. In the configuration of the present embodiment, it is possible to easily increase the number of the fluorescent lamps 91, and it is possible to create a display device with higher luminance.

As shown in the perspective view of FIG. 14, a diffusion plate 92 may be provided between the fluorescent lamp 91 and the display. The same driving method and driving circuit as those described in the first embodiment can be used.

The present invention is not limited to the above embodiment. For example, the surface of the transparent light guide fixed electrode portion on which the transparent conductive layer is formed may not be curved.

In this embodiment, the insulating layer is formed on the transparent conductive layer. However, the insulating layer is formed on at least one of the surface of the transparent conductive layer and the surface of the movable film electrode to prevent short circuit. It should just be done. However, if an insulating layer is formed on the surface of the movable film electrode, the weight increases, so a larger electric field must be applied to move the movable film electrode. Therefore, a transparent insulating layer is formed only on the surface of the transparent conductive layer. Is preferred.

[Third Embodiment] Next, an embodiment of an optical shutter for shortening the opening / closing time by simultaneously opening and closing a plurality of movable film electrodes will be described.

FIG. 15 shows a conceptual diagram of the third embodiment of the present invention. FIG. 15A is a sectional view of a basic element (shutter unit) of a shutter, and FIG. 15B is a diagram for explaining the principle of operating a plurality of shutter units simultaneously.

In FIG. 15 (a), reference numeral 101 denotes a cantilever movable film electrode.
Covered with conductive material. The movable film electrode 101 has a property of blocking light.

A light guide 1 having a transparent fixed electrode 102 on the surface opposite to one surface of the movable film electrode 101
04 is provided, and a light guide 105 having a light-shielding fixed electrode 103 on the surface is provided opposite the other surface. 104 and 105 have the same structure. One curved surface of the light guide is covered with a transparent fixed electrode 102, and the other vertical surface is covered with a light-shielding fixed electrode 103.

The potential of the movable film electrode 101 is
It can be controlled externally, and its potential is set to Vs
And In addition, the potentials of the two transparent and light-shielding fixed electrodes can be externally controlled, and the respective potentials are set to Va,
b.

The movable film electrode 101 is bent by the electrostatic field based on the potential difference between Vs, Va, and Vb, and the transmission and non-transmission of light passing through the light guide can be controlled.

That is, if there is a sufficient potential difference between Vs and Va and Vb = Vs, the movable film electrode 101
Falls down toward the transparent fixed electrode 102 to block transmitted light. If there is a sufficient potential difference between Vs and Vb,
If a = Vs, the movable film shutter 101 is drawn toward the translucent fixed electrode 103, the shutter is opened, and light passing through the light guide is transmitted.

Note that an insulating film is formed on the surface of the movable electrode of the movable film electrode 101 or on the surfaces of the fixed electrodes 102 and 103 so that the movable electrode and the fixed electrode are not electrically short-circuited. .

Next, the display principle will be described with reference to FIG. First, light emitted from the light source 113 passes through a shutter set 112 composed of a plurality of shutter units, passes through a color filter 111, and passes through an eye 11 of an observer.
Reaches 0. Naturally, with the shutter set 112,
Light transmission and non-transmission are determined. The transparent fixed electrode 102 of the shutter unit and the light-shielding fixed electrode 10
3 is indicated by a bold black line for simplification of the drawing.
The same applies to the following drawings.

The movable electrode 1 in the shutter set 112
01 are all electrically connected, and the potential is Va. Similarly, the light-shielding fixed electrode 103 in the shutter set 112 is also electrically connected, and the potential is set to Vb.

In FIG. 15B, the shutter set 11
2 has four shutter units, and these four shutter units are simultaneously opened and closed.

As described above, the simultaneous opening and closing of a plurality of shutter units makes it possible to increase the speed of the shutter. This is because the small shutter has a smaller swing width of the cantilever and the electric field intensity applied to the movable film shutter is higher than the large shutter, so that high-speed response is possible. Therefore, when a shutter for turning light on and off is formed, a response speed can be increased by using a plurality of shutters having a small amplitude rather than by using a shutter having a large amplitude.

[Fourth Embodiment] Next, a description will be given of an embodiment of a display device capable of displaying excellent halftones by using the shutter set of the third embodiment.

FIG. 16 is a connection diagram when a plurality of shutter sets 112 according to the third embodiment are combined. In the example of FIG. 16, the shutter sets are arranged in a 3 × 2 matrix, and one pixel is constituted by six shutter sets. That is, one shutter set corresponds to a sub-pixel.

Furthermore, the transmitted light amounts of these six sub-pixels are all different. The width of the shutter unit is in the normal direction to the drawing and cannot be shown in the drawing.
The widths (depths) of 202 and 203 are narrow, and 204 and 20
The width (depth) of 5,206 is wide.

Further, 201 and 204 have one shutter unit, and 202 and 205 have two shutter units.
, 203 and 206 are composed of six shutter units. Thus, the amount of transmitted light of each pixel is changed.

In this case, there are a plurality of pixels (6 in this example).
) Sub-pixels can display halftones. That is, by selectively opening and closing the six sub-pixels, the amount of transmitted light changes in area, and a halftone is displayed. This principle will be described in detail below.

In FIG. 16, s1, s2, and s3 are signal lines, which are electrically connected to the movable electrodes of each sub-pixel. Also.
a1 and b1 are scanning lines in the first row, and a2 and b2 are scanning lines in the second row. By setting the potentials of these signal lines and scanning lines, individual image information can be sent to six sub-pixels.

If one pixel has eight sub-pixels, and the area ratio of the small pixels is 1, 2, 4, 8, 1
If the number is 6, 32, 64, or 128, 256 gradations can be created by a combination of driven sub-pixels. In general, with 256 gradations, a television image can be displayed without any problem.

This will be described with reference to FIGS.
In order to display television images, generally 640 × 48
It is necessary to prepare 0 pixels. FIG. 17 is a diagram of one pixel viewed from the color filter side. 211,2
Reference numerals 12 and 213 denote RGB of the color filter, respectively.

FIG. 18 is a diagram in which one of R, G, and B, for example, B is taken and a color filter is removed, and this diagram corresponds to the above-described one pixel (213 '). The size of one pixel is, for example, 1.5 × 0.5 mm. Pixel 213 '
As described above, there are eight types of sub-pixels having different sizes, and the number given to the reference symbol S indicating the sub-pixel in FIG. 18 indicates the area ratio. That is, S1: S2:
S4: S8: S16: 32: S64: S128 = 1:
2: 4: 8: 16: 32: 64: 128.
Note that the frame 214 covering the periphery of the sub-pixel is a light-shielding black matrix that separates the sub-pixels.

FIG. 19 is a sectional view of the largest sub-pixel among the above-mentioned eight sub-pixels. Also in this embodiment, the optical system is configured as shown in FIG. 15B of the third embodiment, and the shutter set 112 is replaced with the shutter set 215. Referring to FIG. 15B, light emitted from the light source 113 is transmitted to the shutter set 215.
Through the color filter 110 (FIG. 19-21).
Pass through 3) and enter observer eye 110. Note that FIG.
Here, the fixed electrode of the shutter set 215 is omitted for simplification.

The shutter set 215 has eight shutter units, and the pixel 213 'has a total of thirty shutter units. With this structure, a television image having a halftone can be displayed.

As a method of changing the light transmission amount of a pixel, in addition to changing the width and number of shutter units,
The amount of light transmission can be changed by changing the size of the opening of the black matrix 214 described above.

FIG. 20A shows an example in which the size of the opening is changed. The width of the shutter unit of S1 is set to １ ／ of the width of the shutter unit of S1 in FIG. 18 to reduce the opening as a whole. That is, the size of the opening is adjusted by changing the width of the shutter unit.
The advantage of this arrangement is that the number of shutter units can be reduced. In this case, the number of shutter units is 16 per pixel. The disadvantage of this embodiment is that the aperture ratio is low.

In FIG. 20B, the width of the shutter unit in S1 is set to half the width of S1 in FIG. In this case, the number of shutter units is ten. FIG. 21A shows the same number of shutter units as in FIG. 20B, except that the arrangement of the openings is changed.

In FIG. 21B, the number of shutter units is the same as that in FIG. 18, but the size of the shutter is line-symmetric. This is to make all the widths of the shutter units the same. By making the width the same,
Productivity can be increased. The size of the opening is determined by the black matrix 214.

In FIG. 21C, in order to maximize the aperture ratio, the intervals between sub-pixels are reduced without using a black matrix.

The light guide of the shutter unit is not always necessary, and the fixed electrodes 102 and 103 may be plate electrodes as shown in FIG.

Next, a description will be given of an embodiment of a display device capable of displaying a moving image at the same time as halftone display (dither gradation) as described in the fourth embodiment.

[Fifth Embodiment] In a fifth embodiment, the configuration of a basic display device capable of displaying halftones and moving images will be described. There are two fixed electrodes, which are characterized by the potential of the signal line in the holding state.

As a display device for an office, a moving image display is required in addition to a halftone display. In the case of displaying a moving image, the screen definition itself does not need to be so high.
In the case of the SC moving image, 640 × 480 pixels are sufficient. However, sufficient halftone display is required for moving image display.

First, the principle of the present invention will be described. FIG.
FIG. 4 is a basic circuit diagram for explaining the operation of the movable film shutter. The shutter unit is provided with a movable film electrode 101 of a cantilever and a fixed electrode 102 having a rigid and curved surface as in FIG. 15A of the third embodiment (FIG. 15A). , There are two fixed electrodes,
Here, the description will be made assuming that there is one fixed electrode). The fifth
In the third embodiment, as in the third and fourth embodiments, a transmissive display device in which a light source is installed below a pixel is premised.

A variable power supply V is connected between the movable electrode 101 and the fixed electrode 102 so that an arbitrary voltage can be applied. The root of the movable film electrode is fixed, and when the voltage of the variable power supply V is gradually increased, the tip of the movable film electrode 101 is displaced toward the fixed electrode 102. FIG. 24 shows the relationship between the tip displacement X and the applied voltage.

The displacement of the tip of the movable film electrode 101 is
It increases with an increase in the applied voltage, but when it reaches a certain critical voltage Vc, it suddenly reaches the surface of the fixed electrode 102. Thereafter, even if the voltage is further increased, the displacement does not increase. Conversely, when the voltage is lowered, the displacement does not change even if the voltage further drops below Vc, and the same state is maintained up to a certain voltage Ve. When the voltage reaches a certain voltage Ve, the movable electrode suddenly moves away from the fixed electrode, and the displacement returns to almost the initial value. That is, the relationship between the displacement of the tip of the movable electrode and the applied voltage indicates hysteresis.

The values of Vc and Ve are based on the Young's modulus, thickness, length and width of the movable film electrode, the curved shape of the fixed electrode, the thickness and dielectric constant of the insulating film interposed between the movable film electrode and the fixed electrode. It is determined from such as. However, when a large number of such shutter units exist, there is a possibility that the above-described various elements have some variation, and the values of Vc and Ve vary. A voltage that allows for the variation width of Vc is defined as Vma. Therefore, when there are a large number of shutter units, the maximum value of Vc considering the variation is Vc
+ Vma, and the minimum value is Vc-Vma.

In FIG. 23, only one fixed electrode is provided for one movable electrode. FIG. 25 shows a case where there are two fixed electrodes for one movable electrode. FIG.
In this case, the electrostatic force acting on the movable electrode is in only one direction. Therefore, in order to restore the deflection of the movable electrode, it is necessary to use the elastic force of the movable electrode itself. When returning by elastic force, the return speed is determined by the Young's modulus, thickness, and length of the movable film, and the return is accompanied by some vibration.

As shown in FIG. 23, if two fixed electrodes are provided for one movable electrode, electrostatic force can be used in either direction, and the shutter speed can be improved and vibration can be prevented. become. Therefore, the following embodiments will be described using a configuration using two fixed electrodes.
However, the present invention can be applied to a case where a fixed electrode having asymmetrical structure as shown in FIG.

Although the electrodes are schematically illustrated in FIG. 25, specifically, as shown in FIG. 26A, for example, the fixed electrode 102 is formed on the curved surface of the transparent light guide 104. The fixed electrode 103 is a transparent conductive electrode formed in
The movable electrode 101 can be formed of a light-blocking conductive film, which is a metal film formed on the transparent light guide 104. It goes without saying that the base on which the fixed electrode 103 is formed does not need to be transparent. The plane size (pixel size) of the shutter is, for example, 50 μ × 50 μm.

Further, as shown in FIG. 26B, the transparent light guide 104 may be omitted. In addition, the fixed electrode 10
2,103 does not necessarily need to have a curved surface,
As shown in FIG. 26C, the movable electrode 101 may be a parallel plate electrode. However, in this case, the voltage for bending the movable film electrode slightly increases.

As shown in FIGS. 25 and 26, the movable electrode 101 is connected to the signal line s, and the fixed electrodes 102 and 103 are connected to the signal line s.
They are electrically connected to the scanning lines a and b, respectively.

Next, a driving circuit and a driving method of the display device according to the fifth embodiment will be described with reference to FIG. FIG. 27A is a circuit diagram of the present embodiment, and FIG.
(B) is a timing chart showing potentials and timings of various signals applied to signal lines and scanning lines.

In FIG. 27A, a plurality of pixels 100 composed of a plurality of movable film shutters are arranged in a matrix. In each pixel 100, a cantilever-shaped movable electrode 101 includes a first fixed electrode 102 and a second fixed electrode 103.
Sandwiched by Reference numbers S1 to S5 are signal lines for sending an image signal to each pixel. G1a, G1b,
G2a, G2b, G3a, G3b are scanning lines. Each signal line is electrically connected to a plurality of movable electrodes adjacent in the vertical direction. The scanning lines are roughly classified into two types, a and b. Each scanning line on the a side is represented by G1a, G2a, G3a, b
Each scanning line on the side is named G1b, G2b, G3b. These two types of scanning lines a and b are electrically connected to a plurality of first and second fixed electrodes 102 and 103, respectively.

The signal line has a pulse wave obtained by increasing or decreasing the margin voltage Vma in consideration of the amount of variation in the critical voltage Vc, that is, Vc + Vma on the high side and Vc− on the low side.
A pulse wave of Vma is given. Signal line voltage is Vc
At + Vma, when the potential of the scanning line is in the writing state (is at the GND level), the image signal is written to the pixel (light is cut off).

In the image holding state, the scanning lines are G
ND potential. Since the holding state is to hold the image signal as it is, the pixel must maintain that state. Since the two fixed electrodes have the same potential, the movable electrode is closer to the closer fixed electrode regardless of the potential. This is because the electrostatic force is inversely proportional to the square of the distance between the electrodes, and the electrostatic force between the closer fixed electrode is stronger.

Next, the potential of the scanning line when an image signal is written, that is, in the selected state, will be described. As described above, the first fixed electrode 102 is connected to the scanning line a (G1
a, G2a and G3a are collectively referred to. Similarly, the second fixed electrode 102 is connected to the scanning line b (G1b, G2b, G3b
Are collectively referred to. Hereinafter the same).

First, the movable electrode 101 is connected to the second fixed electrode 1.
The case of bending in the direction of 03 (light passing) will be described. In this case, the potential of the scanning line a is set to Vc + Vma, and the potential of the scanning line b is set to GND. If the signal line potential is Vc + Vma, the movable electrode 101 electrically connected to the signal line approaches the second fixed electrode 103 having a potential difference. If the signal line potential is Vc-Vma, the potential difference is insufficient, and the movable electrode 101 cannot be drawn toward the second fixed electrode 103.

Next, the movable electrode 101 is connected to the first fixed electrode 1.
The case of bending in the direction of 03 (light is blocked) will be described. The potential of the scanning line a is set to GND, and the potential of the scanning line b is set to Vc + Vma. If the signal line potential is Vc + Vm
a, the movable electrode 10 electrically connected to the
1 approaches the first fixed electrode 102 having a potential difference. If the signal line potential is Vc-Vma, the potential difference is insufficient, and the movable electrode 101 cannot be drawn toward the first fixed electrode 102.

Therefore, writing or non-writing of an image signal can be selected depending on the potential of the signal line. FIG. 28 shows the relationship between each combination of the scanning line potential and the signal line potential and the pixel state.

[Sixth Embodiment] Next, an embodiment in which the stability of the holding state is improved will be described. The circuit diagram of the display device of the sixth embodiment is shown in FIG. 27 of the fifth embodiment.
Same as (a). The sixth embodiment differs from the fifth embodiment in the potential of the scanning line in the holding state.

FIG. 29 is a timing chart showing potentials and timings of various signals applied to signal lines and scanning lines. In the sixth embodiment, a voltage Vhold is applied to each scanning line signal as the potential in the holding state.

FIG. 30 is a diagram showing the relationship between the displacement X of the tip of the movable electrode described in FIG. 24 and the potential difference between the fixed electrode and the movable electrode for the display device of the sixth embodiment. Basically, it is the same as FIG.
Is set to a voltage higher than the voltage Ve at which the tip displacement X suddenly returns to zero.

As described above, in the fifth embodiment, when the two scanning line potentials in the holding state are set to GND, the movable electrode always falls on one of the fixed electrodes. However, according to the driving method as in the sixth embodiment, since the scanning line voltage in the holding state is Vhold higher than Ve, the movable electrode suddenly returns to the original state (ie, zero displacement).
Never go back to In this Vhold, the movable electrode is 2
It has two stable states. In other words, this means that the movable electrode is in a stable state regardless of which fixed electrode side has the movable electrode.

Therefore, the display device of the present embodiment can maintain a more stable holding state than the fifth embodiment. FIG. 31 shows the relationship between each combination of the scanning line potential and the signal line potential and the pixel state in the sixth embodiment.

[Seventh Embodiment] Next, a seventh embodiment of the present invention will be described. The seventh embodiment relates to a display method that makes it possible to switch between high-definition binary display and moving image display of dither gradation by applying the configuration of the sixth embodiment.

FIG. 32 is a circuit diagram of a display device according to the seventh embodiment. There are two types of scanning lines, a scanning line a (Ga11, Ga12,) described on the left side of the pixel group and a scanning line b (Gb11, Gb12,) described on the right side.

In this embodiment, the scanning line is Ga1 on the a side.
1 to Ga14, Ga21 to Ga24, Gb1 on the b side
They are divided into groups of four, such as 1 to Gb14 and Gb21 to Gb24. The potentials actually applied to the scanning lines are supplied from reference potential lines A1 to A4 or B1 to B4. Scanning line Ga1
1, a switch SW that switches the potential of the scanning line to the reference potential line side or the GND side.
a, a signal for opening and closing SWb.

In each group of scanning lines, the first scanning line (G
a11, Gb11, Ga21, Gb21) can be connected to the reference potential line A1 on the a side and to the reference potential line B1 on the b side. In addition, the second scanning line (Ga12,
Gb12, Ga22, Gb22) are the third to A2 and B2.
Scan lines (Ga13, Gb13, Ga23, Gb23)
Indicates the fourth scanning line (Ga14, Gb14,
Ga24, Gb24) can be connected to A4 and B4, respectively.

On the other hand, the signal line is electrically connected to the movable electrode of each pixel in the vertical direction as in the fifth and sixth embodiments.

Next, an example in which high definition display and halftone / moving image display are performed using the display device having such a configuration will be described.

(High Definition Mode) FIG. 32 shows a state of high definition display. In this state, the potentials of the reference potential lines are all set to Vc + Vma, and the scanning lines are sequentially written from the top of the screen, ignoring the above-described grouping of the scanning lines. The timing chart is shown in FIG.
Basically, the procedure is the same as that described in the fifth embodiment. As in the fifth embodiment, the scanning lines a and b are turned on alternately and sequentially, and writing of light passing and non-passing is sequentially performed individually.

In FIG. 33, the commands W and P are given as commands, and this is for writing (W: Write) or ignoring (P: Pass) for each writing of light passing and non-passing. Is indicated to the signal line. Vs1 is an example of the potential of the signal line. Vc + Vma for writing (W) and Vc for neglecting (P).
−Vma.

In this case, since the size of one pixel is about 50 μm × 50 μm as described above, a sufficient resolution can be obtained.

(Moving Picture, Halftone Mode) FIG.
5 shows a circuit state when a halftone is displayed. The halftone display of the present embodiment is a so-called dither gradation using a plurality of pixels. In the present embodiment, 4 × 4 sub-pixels constitute one pixel. That is, 16 sub-pixels make up one pixel. Therefore, there is a display capability of 16 gradations. If one pixel is composed of 10 × 10 sub-pixels, 100 gradations can be realized. With 640 × 480 pixels, it becomes possible to display an NTSC moving image.

At this time, if the sub-pixels are written one by one, the writing time per sub-pixel becomes short, and there is a possibility that sufficient writing cannot be performed. Therefore, in this embodiment, writing is performed for each pixel. That is, each of a and b connected to the pixels in the same row is 1
Assuming that one scanning line is one pair, four scanning line pairs (eight scanning lines in total of a and b) are simultaneously written. Four more signal lines, for example, signal lines S1-S4
Are driven simultaneously. In the case of NTSC, the writing time given to one pixel is 60 μs.

In the example of FIG. 34, the scanning lines Ga11-Ga1
4 and Gb11-Gb14 are connected to the respective reference potential lines, and the pixels on these scanning lines are in a writing state. On the other hand, Ga21-Ga24 and Gb21-Gb2
4 is in a holding state.

FIG. 35 shows a timing chart of the present embodiment. FIG. 36 is a timing chart similar to FIG. 35, specifically showing the potential VG of the scanning line.

In order to display a halftone, in this display state, the potentials of the reference potential lines are individually different. At the time of non-light-passing writing, since the movable electrode is drawn toward the scanning line a, the potential of the scanning line b of the selected pixel is all changed to Vc.
In order to set the potential to + Vma, the potentials of the reference potential lines B1 to B4 are all set to Vc + Vma.

On the other hand, the potentials of the scanning lines a are intentionally different from each other in order to display a halftone. For example, the potential of the reference potential line A1-A4 is set as A4>A3> A2
> A1, and the potential of the scanning line a is also VGa14.
>VGa13>VGa12> VGa11. At this time, depending on the length of time during which the potential of the signal line is Vc + Vma, sub-pixels to be written and sub-pixels to which no writing is performed appear in the same pixel.
That is, whether or not writing is performed is determined by “the time when the potential of the signal line is Vc + Vma” ×
It is determined by the value of "potential difference between movable electrode and scanning line". Therefore, halftone display can be performed in the pixel depending on the length of time during which the signal line is at Vc + Vma.

In the case of light passing writing, the reference potential line A1
All potentials of −A4 are set to Vc + Vma. On the other hand, the potentials of the scanning lines b are intentionally different from each other in order to display a halftone. For example, the reference potential line B1-
The potential of B4 is set to satisfy B4>B3>B2> B1, and the potential of the scanning line b is also VGb14>VGb13> VGb.
12> VGb11.

The potential of the signal line is Vh except for the time of Vc + Vma. This is a voltage for realizing Vhold of the sixth embodiment, and is a potential at which the movable electrode holds the state regardless of the potential of the scanning line.

In the holding state, the potential of the scanning line is set to GND or Vhold as in the fifth or sixth embodiment.

In the fifth to seventh embodiments, the light-transmitting display device has been described as an example. However, the present invention is applied to a reflective display device using a shutter set as shown in FIG. Can be. FIG. 37A shows fixed electrodes 102 ′ and 103 ′ with bent tips and movable electrode 10.
FIG. 15B is a view in which the shutter set 1 shown in FIG.
This corresponds to No. 12. Fixed electrode 102 'of one pixel
Partially overlap with the fixed electrode 103 'of the adjacent pixel. As an actual display device, the display devices are arranged in such a manner that they are overlapped with each other, so that the space use efficiency is improved.

The tip of the above-mentioned electrode is bent substantially at a right angle. The tip of the movable electrode can be hidden below the tip of one fixed electrode and can exit above the tip of the other fixed electrode. If the colors of the tips of the fixed electrode and the movable electrode are changed, display can be performed by inserting and removing the tip of the movable electrode. In the case of a color image, the tip of the movable electrode is RGB or CMY (cyan,
(Magenta, Yellow) and one set of RGB or CMY forms one pixel.

As shown in FIG. 37 (b), the ratio between the actual bent portion and the length of the cantilever or fixed electrode is as follows.
It is preferable to be as large as possible. This is for minimizing the step in the pixel portion.

With the above configuration, it is possible to provide a movable film type display device capable of displaying both high definition image quality required for an information display reflection type display device and a halftone moving image display.

[0169]

As described above, according to the first aspect of the present invention, a large-screen display device can be easily formed by combining a plurality of display devices, and the joint at the time of combination can be improved. It is hardly visible.

In addition, since it can be formed using an inexpensive member, the cost can be reduced.

According to the second aspect of the present invention, the opening / closing time can be reduced by simultaneously opening and closing the pixels (or sub-pixels) formed by the plurality of shutter units.

Further, eight sub-pixels are provided in one pixel, and their area ratio is, for example, 1: 2: 4: 8: 16: 3.
If the ratio is 2: 64: 128, 256 kinds of gradations can be displayed by a combination of these sub-pixels. Even a sub-pixel having a large area is composed of a plurality of shutter units, and the swing width of each movable electrode can be 100 μm or less. As a result, writing for 60 μsec becomes possible, and moving images can be handled.

According to the third aspect of the present invention, since the predetermined potential is applied to the signal line even in the holding state, the voltage amplitude of the signal line is minimized, and the movable film type display device with low power consumption is used. Can be realized.

Further, one pixel is constituted by a plurality of scanning lines and a plurality of signal lines, and the potentials of the plurality of scanning lines constituting one pixel are different from each other, and one signal line is simultaneously applied to the plurality of scanning lines. The sub-pixels (scanning lines) to be written and the sub-pixels (scanning lines) not to be written appear according to the time when the potential of the pixel becomes the writing potential. If the writing time of a plurality of signal lines constituting one pixel is changed, sub-pixels to be written and sub-pixels not to be written are two-dimensionally selected, thereby enabling halftone display by dither gradation.

Further, since the size of the shutter unit constituting one pixel (sub-pixel) is about 50 μm × 50 μm, if the driving of the scanning line is switched to the line sequential scanning which is the same as the conventional one, a high definition image display is achieved. Can also be done.

As a result, it is possible to provide a movable film type display device capable of displaying both high-definition image quality and halftone moving image, which are required of the display device.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration for one pixel of a movable film type display device according to a first embodiment.

FIG. 2 illustrates the principle of a movable film type display device.

FIG. 3 is a plan view showing a configuration of a movable film type display device according to the first embodiment.

FIG. 4 is a sectional view showing a configuration of a movable film type display device according to the first embodiment.

FIG. 5 is a perspective view showing a configuration of a pixel unit of the movable film type display device.

FIG. 6 is a circuit diagram showing a circuit configuration of a movable film type display device.

FIG. 7 is a circuit diagram showing a circuit configuration of a movable film type display device.

FIG. 8 is a circuit diagram showing a circuit configuration of a movable film type display device.

FIG. 9 is a diagram for explaining the driving method of FIG. 8;

FIG. 10 is a perspective view showing a configuration of a movable film type display device.

FIG. 11 is a perspective view showing a configuration of a movable film type display device.

FIG. 12 is a perspective view showing a configuration for one pixel of a movable film type display device according to a second embodiment.

FIG. 13 is a view showing a configuration of a movable film type display device according to a second embodiment.

FIG. 14 is a perspective view showing the overall configuration of a movable film type display device according to a second embodiment.

FIG. 15A is a sectional view of a shutter unit of a display device according to a third embodiment of the present invention, and FIG. 15B is a schematic diagram for explaining the display principle of the display device according to the third embodiment; It is.

FIG. 16 is a connection diagram illustrating a pixel configuration of a display device according to a third embodiment.

FIG. 17 is a diagram showing an arrangement of color filters in a display device according to a fourth embodiment of the present invention.

FIG. 18 is a plan view illustrating a configuration of one pixel of a display device according to a fourth embodiment.

FIG. 19 is a cross-sectional view taken along the line AA of FIG. 18 and indicated by a circle B;

FIG. 20 is a plan view of a modification of FIG. 18;

FIG. 21 is a plan view of another modification of FIG. 18;

FIG. 22 is a schematic diagram showing an example in which a fixed electrode is a parallel plate type in the shutter unit of the fourth embodiment.

FIG. 23 is a connection diagram of a shutter unit and a power supply for explaining the principle of the fifth embodiment of the present invention.

FIG. 24 is a characteristic diagram showing a relationship between a displacement X of a movable electrode tip of the shutter unit of FIG. 23 and an applied voltage.

FIG. 25 is a connection diagram illustrating a method for connecting signal lines and scanning lines to the shutter unit according to the fifth embodiment.

FIG. 26 is a sectional view showing a configuration example of a shutter unit according to a fifth embodiment.

FIG. 27A is a basic connection diagram of the display device according to the fifth embodiment, and FIG. 27B is a timing chart of various signals for driving the circuit of FIG.

FIG. 28 is a table summarizing the relationship between the potentials of signal lines and scanning lines and the states of pixels in the fifth embodiment.

FIG. 29 is a timing chart of various signals according to the sixth embodiment.

FIG. 30 is a characteristic diagram for explaining the relationship between Vhold shown in FIG. 29 and Ve in FIG. 24;

FIG. 31 is a table summarizing the relationship between the potentials of signal lines and scanning lines and the states of pixels in the sixth embodiment.

FIG. 32 shows a display device according to a seventh embodiment of the present invention.
FIG. 4 is a connection diagram when driving in a high-definition mode.

FIG. 33 is a timing chart of various signals for high-definition mode driving according to the seventh embodiment.

FIG. 34 is a connection diagram of the display device according to the seventh embodiment when driving a moving image in a halftone mode.

FIG. 35 is a timing chart centering on a signal of a reference potential line when driving a moving image in a halftone mode according to the seventh embodiment.

FIG. 36 is a timing chart centering on scanning line signals when driving a moving image in the halftone mode according to the seventh embodiment.

FIG. 37A is a configuration example of a shutter set when the fifth to seventh embodiments are applied to a reflective display device,
(B) is a schematic diagram explaining a desirable shape of the reflection type shutter unit.

FIG. 38 is a diagram illustrating characteristics of a conventional display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Transparent light guide fixed electrode part 11 ... Transparent light guide 12 ... Transparent conductive layer 13 ... Transparent insulating layer 14 ... Black matrix 15 ... Opening 21 ... Reflector 22 ... Movable film electrodes 31, 32 ... Electrode 33 ... Switch 34 ... Battery 35 ... Fixed electrode 36 ... Movable electrode 37 ... Fixed electrode 40 ... Display unit 41 ... Display unit 42 ... Fluorescent lamp 43 ... Drive circuit 44 ... Color filter 51 ... Circuit board 52 ... Drive IC 53 ... Wiring 54 ... Connector Part 55: Transparent conductor part 61 ... Signal source 62 ... Scan driving IC 71 ... Signal driving IC 72 ... Signal line 81 ... Fixed electrode 82, 83 ... Scan line 84, 85 ... Potential changeover switch 86 ... Signal line 87 ... Potential Changeover switch 88 Power supply 91 Direct fluorescent lamp 92 Diffuser

Claims (22)

[Claims] 1. A light guide fixed electrode portion which is made of a transparent material and guides light incident from the outside to a surface portion having a transparent conductive layer and emits the light, and said transparent conductive material of said light guide fixed electrode portion. A flexible conductive light-shielding plate, one end of which is fixed and arranged so as to pass the emitted light, facing the layer, and applying a potential difference to the conductive light-shielding plate and the transparent conductive layer. An electrostatic force generating means for generating an electrostatic force between the transparent conductive layer and the conductive light-shielding plate, comprising: when the potential difference is applied to the conductive light-shielding plate and the transparent conductive layer, The display device, wherein the conductive light-shielding plate is displaced around the one end in accordance with the electrostatic force and shields the surface of the light guide fixed electrode portion. 2. The conductive light-shielding plate is arranged in a matrix to form a plurality of conductive light-shielding plates, and the light guide fixed electrode portion is formed by arranging the transparent conductive layers in the matrix. Forming a plurality of light guide fixing electrodes each having a plurality of transparent conductive layers, wherein the electrostatic force generating means is provided between each of the plurality of conductive light shielding plates and a corresponding one of the plurality of transparent conductive layers; And means for giving an independent potential difference to the control signal.
The display device according to claim 1. 3. The display device according to claim 2, wherein the plurality of light guide fixing electrodes arranged in the same row are formed integrally. 4. The method according to claim 2, wherein the plurality of transparent conductive layers of the plurality of transparent light guide fixed electrode portions arranged in the same row direction are electrically connected to each other. Display device. 5. The display device according to claim 1, wherein said surface portion of said transparent light guide fixed electrode portion is curved. 6. The display device according to claim 1, wherein a light-shielding frame is formed around the transparent conductive layer of the light guide fixing electrode portion. 7. A plurality of plate-shaped fixed electrodes, and a plurality of light-shielding cantilever-shaped movable film electrodes respectively opposed to the plurality of fixed electrodes and formed to form a light passage portion. A plurality of optical shutter units comprising: a plurality of fixed electrodes; each of the plurality of fixed electrodes; and a corresponding one of the plurality of movable electrodes, selectively generating an electrostatic force to selectively flex the plurality of movable electrodes. And an electrostatic force generating means for selectively blocking the light passing portions of the plurality of optical shutter units, wherein the plurality of optical shutter units are each provided with an arbitrary number of optical shutter units adjacent to each other. Comprising a plurality of optical shutter sets, wherein in each of the plurality of optical shutter sets, the plurality of fixed electrodes are electrically connected to each other, and the plurality of movable electrodes are electrically connected to each other. Being connected to each other, the electrostatic force generating means simultaneously generates an electrostatic force between each of the plurality of fixed electrodes and a corresponding one of the plurality of movable electrodes, so that the plurality of adjacent optical shutters are formed. The light passing portions of the unit are simultaneously shielded, and the plurality of shutter sets are selectively closed by the electrostatic force generation means selectively generating electrostatic force in the plurality of shutter sets. Display device. 8. The plurality of optical shutter sets constitute a plurality of optical shutter groups each including an arbitrary number of optical shutter sets adjacent to each other, and in each of the plurality of shutter groups, the plurality of shutters are provided. The set is, by the electrostatic force generating means,
The display device according to claim 7, wherein the display device is selectively closed. 9. The method according to claim 8, wherein, in each of the plurality of shutter groups, an amount of the light passing through the shutter group is controlled by a number of the plurality of shutter sets to be closed. The display device according to the above. 10. The size of the plurality of shutter sets included in each of the plurality of shutter groups,
The display device according to claim 8, wherein the amount of light passing through the shutter group is controlled by setting the shutter sets differently from each other and selectively closing the plurality of shutter sets. 11. A ratio of a light passing amount of the plurality of shutter sets included in each of the plurality of shutter groups to a minimum value thereof is a ratio of an integral power of 2. The display device according to claim 10, wherein 12. The display device according to claim 8, wherein said plurality of shutter groups constitute a plurality of pixels capable of dither gradation. 13. A cantilever-shaped light-shielding movable film electrode having one end fixed thereto, and a first film-insulating opposing, opposing, and sandwiching the movable electrode sandwiched from both sides. And the second fixed electrode, wherein the first fixed electrode has a portion separated from the movable electrode to form a light passage, and the first and second fixed electrodes; A first insulating material interposed between the first fixed electrode, a second insulating material interposed between the movable electrode and the second fixed electrode, and the first fixed electrode A first voltage source that supplies a desired voltage to the second fixed electrode, a second voltage source that supplies a desired voltage to the second fixed electrode, and a third voltage source that supplies a desired voltage to the movable electrode. When a potential difference is applied between the movable electrode and the first fixed electrode, an electrostatic force Thereby, the movable electrode is attracted to the first fixed electrode to block the light, and when a potential difference is given between the movable electrode and the second fixed electrode, the movable electrode is moved by electrostatic force. The electrode is attracted to the second fixed electrode and allows the light to pass therethrough. When the potential difference between the first fixed electrode and the movable electrode is gradually increased, the movable electrode When the potential that reaches the first electrode for the first time via the first insulating material is V1, the third voltage source supplies the movable electrode with a voltage obtained by adding a predetermined margin voltage V2 to V1. The first voltage source supplies one of a voltage obtained by adding V2 to V1 and a ground voltage to the first fixed electrode, and the second voltage source adds the V2 to V1. The other of the grounded voltage and the ground voltage Is supplied to the fixed electrode, the movable electrode, whichever is greater towards the potential difference between the potential difference and the second fixed electrode and the first fixed electrode,
A display device that approaches and opens and closes the passage of the light based on the difference in the electrostatic force. 14. The second fixed electrode has a structure symmetrical to the first fixed electrode with respect to the movable electrode, and gradually increases a potential difference between the second electrode and the movable electrode. In this case, the potential at which the movable electrode first reaches the second electrode via the second insulating material is substantially the same as the potential V1 of the first fixed electrode. The display device according to claim 13, wherein: 15. An optical shutter comprising said movable electrode and said first and second fixed electrodes is arranged in a plurality of rows and columns, said plurality of optical shutters being arranged in each of said rows, and each of said plurality of optical shutters corresponding to said plurality of rows. A plurality of signal lines connected to the movable electrodes of each of the optical shutters; and a plurality of signal lines arranged for each of the rows, each being connected to the first fixed electrode of each of the corresponding plurality of optical shutters. A first scanning line, and a plurality of second scanning lines that are arranged for each row and that are connected to the second fixed electrode of each of the corresponding plurality of optical shutters. Claim 1.
4. The display device of 4. 16. The movable electrode and the first and second electrodes.
The potential difference between any one of the fixed electrodes
When gradually lowering from V1, the potential at which the movable film electrode first departs from any one of the first and second fixed electrodes is V3, which is higher than V3,
When the potential lower than V1 is V4, the state in which the movable electrode is attracted to the one of the first and second fixed electrodes is the potential of the first and second fixed electrodes. The display device according to claim 14, wherein the display device is held by being set to V4. 17. The method according to claim 17, wherein the plurality of first scanning lines are k (k is 2
(Integer above) The plurality of groups are divided into a plurality of groups, and k first scanning lines included in an arbitrary one of the plurality of groups are k first reference potential lines and k first scanning lines. Each of the plurality of second scanning lines is electrically connected to a corresponding one of the plurality of first scanning lines via a first switching switch having a switching function of connecting one of the scanning lines to a ground line. Correspondingly, each of the groups is divided into k groups, and k second scanning lines included in an arbitrary one of the groups are k second reference potential lines and the second scanning lines. The display device according to claim 15, wherein the display devices are electrically connected to each other via second changeover switches each having a changeover function of connecting the first to the ground line. 18. The k first scanning lines included in an arbitrary one of the plurality of groups may be, via the changeover switch, an arbitrary potential higher than a ground potential and lower than the V1. Respectively, and the k number of second scanning lines corresponding to the k number of first scanning lines have a potential of V1 + V2, respectively. And a selected signal line of the plurality of signal lines is V1 + V
The light is selectively blocked by the plurality of optical shutters included in the arbitrary one of the plurality of groups according to a time period in which the plurality of optical shutters are held at a potential of 2. 18. The display device according to item 17. 19. The k number of second scanning lines included in any one of the plurality of groups may be, via the switch, any potential greater than ground potential and less than V1. Are connected to the k second reference potential lines, respectively, and k first scan lines corresponding to the k second scan lines are respectively connected to the k first scan lines having a potential of V1 + V2. 1
And a selected signal line among the plurality of signal lines is V1 + V
18. The light according to claim 17, wherein the plurality of light shutters included in the arbitrary one of the plurality of groups selectively pass the light in accordance with a time that the plurality of light shutters are held at a potential of 2. The display device according to the above. 20. In the plurality of optical shutters included in an arbitrary one of the plurality of groups, a potential difference between the movable electrode and the second fixed electrode and a potential difference between the plurality of signal lines. When the product of the selected signal line and the time during which the selected signal line is held at the potential of V1 + V2 becomes a predetermined value or more, the movable electrode is drawn to the first fixed electrode, and the light is blocked. The display device according to claim 17, wherein the display device is operated. 21. The plurality of signal lines included in the arbitrary one of the plurality of groups according to a time during which a selected one of the plurality of signal lines is held at a potential of V1 + V2. The display device according to claim 17, wherein an amount of the light passing through an optical shutter changes. 22. The plurality of optical shutters connected to a selected one of the plurality of signal lines among the plurality of optical shutters included in an arbitrary one of the plurality of groups. 18. The display device according to claim 17, wherein only the electrode having a potential difference between the movable electrode and the first fixed electrode that is equal to or greater than a predetermined potential difference allows the light to pass therethrough.