JP3545391B2 - Projection display device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an information input / output device using a projection type liquid crystal electro-optical device.
The present invention relates to an information input / output device capable of inputting information on a position on a display surface specified by contact, light emission, or the like on the display surface.
Further, the present invention relates to an information input / output device that reads image information such as a drawing arranged on a display surface or displays the read image information.
[0002]
[Prior art]
Conventionally, for information displayed on a display surface of a display device such as a CRT or a liquid crystal electro-optical device, an information signal is externally input on the display surface in the same sense as writing a character or the like with a writing instrument on paper, A device that displays an image corresponding to an input information signal on a display surface is known.
[0003]
An information signal input method to a display device is such that a position detection means for detecting a position on the display surface is provided on the display surface, and when an external force such as pressure, magnetic force, or light is applied to a certain point on the display surface, the external force is applied. The detected position is transmitted to the display device as an information signal, and the displayed image is changed.
[0004]
As a means for detecting a position on the display surface, a touch panel using a light-transmitting resistive film or a transparent electrode matrix, an infrared sensor, or the like is used.
[0005]
In recent years, such an information input / output device generally uses a liquid crystal electro-optical device as a means for displaying image information.
[0006]
With such a configuration, the operator can perform an input as if he / she operates the display content of the display device as it is. Alternatively, by displaying the input information on a display device in which the same coordinate system is set in real time, characters and images can be input as if they were written on paper with a writing instrument.
[0007]
[Problems of the prior art]
However, when the conventional configuration is used using the liquid crystal electro-optical device, various problems occur.
For example, when pressure is applied to the display surface of the liquid crystal electro-optical device, the orientation of the liquid crystal material in the liquid crystal electro-optical device may be disturbed, and display may not be possible.
Further, there has been a problem that display contents change due to magnetism, static electricity, or the like when indicating a position on the display surface, or elements formed in the liquid crystal electro-optical device are destroyed, so that display becomes impossible thereafter. In most cases, information can be input by tracing the display surface with a pen or a finger, and it has not been possible to collectively input information such as a document and an image.
[0008]
For this reason, a solution can be achieved by adopting a configuration in which the liquid crystal electro-optical element is not affected at all by an external force applied to the display surface.
As a liquid crystal electro-optical device capable of such a configuration, a projection type liquid crystal electro-optical device (liquid crystal projector) is known.
The projection type liquid crystal electro-optical device is capable of displaying a large screen with a diagonal of 40 inches or more, but is small, light, requires no adjustment, and is not affected by terrestrial magnetism which is a problem when a large screen is used in a CRT. It is expected to be used as a display device replacing a large screen CRT.
[0009]
The basic configuration of a projection type liquid crystal electro-optical device is to display a transmissive or reflective liquid crystal electro-optical device, irradiate the liquid crystal electro-optical device with light, and expand the transmitted or reflected light through an optical system. An image is projected and displayed on a screen as a display surface.
This projection-type liquid crystal electro-optical device has a front type in which light is projected toward the display surface side (front side) of the screen and reflected light is visually recognized as an image, and a surface opposite to the display surface side of the screen (back side of the screen). It can be distinguished into a rear type in which the transmitted scattered light is projected and visually recognized as an image.
[0010]
However, the projection type liquid crystal electro-optical device can display a large screen, but transmits a position on the display surface arbitrarily designated as an information signal to the display device from a screen surface which is a display surface of an image, There was no device for changing the display content.
[0011]
For this reason, the projection type liquid crystal electro-optical device can display an image such as a movie or a TV, but has not been used in a field requiring a large screen such as a CAD or a work station to simplify the operation.
[0012]
[Problems to be solved by the invention]
The present invention provides an information input device capable of instructing the screen of a projection type liquid crystal electro-optical device with a pen, a finger, or the like, inputting information on a position on the screen, and changing display contents of the liquid crystal electro-optical device. It is an object to provide an output device.
[0013]
Further, according to the present invention, the display content of a display device that displays an image on a large-area screen large enough to be viewed by many people is changed by information directly input on the display surface. It is an object of the present invention to provide an information input / output device that allows the user to input / output information.
[0014]
[Means for Solving the Problems]
The present invention has the following configurations in order to solve the above problems. That is, the present invention
A display device;
A screen on which the image displayed on the display device is enlarged and projected,
Position detecting means for detecting a position of a specific point on the screen arbitrarily designated;
An information input / output device characterized by having:
[0015]
Also, the present invention
Having a liquid crystal electro-optical device, a screen, and an imaging device,
The screen, the image displayed on the liquid crystal electro-optical device is enlarged and projected on the back side,
The imaging device is provided on the back side of the screen and receives light incident from the front side to the back side of the screen.
An information input / output device characterized in that:
[0016]
Also, the present invention
Having a liquid crystal electro-optical device, a screen, and an imaging device,
The screen, the image displayed on the liquid crystal electro-optical device is enlarged and projected on the back side,
The imaging device is provided on the back side of the screen and reads an image present on the front side of the screen.
An information input / output device characterized in that:
[0017]
Also, the present invention
A liquid crystal electro-optical device, a screen, an imaging device, and a position detecting unit,
The screen, the image displayed on the liquid crystal electro-optical device is enlarged and projected on the back side,
The imaging device is provided on the back side of the screen, reads an image present on the front side of the screen,
The position detecting means is provided on a front side of the screen, and detects a position of a specific point arbitrarily designated on the screen.
An information input / output device characterized in that:
[0018]
The present invention is an information input / output device having a screen for displaying an image, and an information input / output mediating means including means for detecting the position of a specific point arbitrarily designated on the screen.
FIG. 1 shows a conceptual diagram of the information input / output device of the present invention. In FIG. 1, 1 is a main body of the information input / output device, 2 is a light source, 3 is a liquid crystal electro-optical device, 4 is an optical system, 5 is a screen, and 6 is position detecting means.
The specific configuration will be described below.
[0019]
In FIG. 1, the optical system is of a rear type. A xenon lamp, a halogen lamp, a metal halide lamp, or the like can be used as the light source 2. The light source 2 has high luminance, high luminous efficiency, RGB color components are distributed in a well-balanced manner, and has a long life. It is desirable to use a metal halide lamp as satisfying the above condition.
[0020]
The light emitted from the light source is applied to the liquid crystal electro-optical device 3 via a condensing optical system (not shown). The light transmitted through the liquid crystal electro-optical device 3 is magnified by the optical system 4 and is projected on a screen 5, and an image displayed on the liquid crystal electro-optical device 3 is magnified and projected on the screen 5.
[0021]
As the operation mode of the liquid crystal electro-optical device, a TN type, an STN type, a scattering type, or the like can be used. As the liquid crystal material used in the liquid crystal electro-optical device, nematic liquid crystal, smectic liquid crystal, ferroelectric liquid crystal, PDLC (polymer dispersed liquid crystal) containing them in a polymer resin, or the like can be used.
[0022]
As the driving method, a simple matrix method or an active matrix type can be used. However, because of high speed and high image quality, an active matrix type in which a switching element, particularly a crystalline thin film transistor is provided for each pixel on a substrate is used. desirable.
[0023]
In particular, in the case of an active matrix type liquid crystal electro-optical device using a crystalline thin film transistor, a switching thin film transistor connected to each pixel and a driving peripheral circuit for driving the liquid crystal electro-optical device are provided on the same substrate. Since a so-called monolithic structure can be used, the size and cost of the device can be reduced, which is preferable.
[0024]
In FIG. 1, the light from the light source is transmitted from the rear of the liquid crystal electro-optical device. However, the liquid crystal electro-optical device is of a reflective type and the display surface side is irradiated with light, and the reflected light is passed through the optical system 4 to the screen. It may be projected.
[0025]
In order to further perform color display, a color filter of three colors of RGB corresponding to each pixel is provided on one of a pair of substrates constituting the liquid crystal electro-optical device, or three liquid crystal electro-optical devices are prepared. The light from the light source is once separated into three colors by a dichroic mirror or the like that reflects only one of the three colors RGB, and the light of each color is incident on a different liquid crystal electro-optical device and transmitted through the liquid crystal electro-optical device. May be synthesized again with a dichroic mirror and projected onto a screen.
[0026]
In the case of this spectroscopic method, three ferroelectric liquid crystal electro-optical devices which are only transmissive and have only a high-speed shutter function in which the entire display surface is composed of one pixel are prepared, and a ferroelectric device which performs only image display is prepared. A display method in which one dielectric liquid crystal electro-optical device is prepared and three colors are switched by a shutter within one frame may be used.
[0027]
A self-luminous display such as a cathode ray tube can be used as the display device.
[0028]
Next, the screen 5 will be described. As a basic configuration of the screen, a substrate having a thickness of 3.0 mm and having light transmitting and scattering properties was used. As the substrate, glass, plastic, or the like can be used, but it is preferable to use a plastic substrate in terms of reducing the weight of the device. In order to improve the brightness of an image, a combination of a Fresnel lens and a lenticular lens may be used. Further, when the contrast is expected to decrease due to external light, a polarizing sheet may be attached to the substrate.
[0029]
When the light from the liquid crystal electro-optical device is diffracted on the screen 5 and the outline of each pixel is blurred, a grid pattern is formed on the front side or the back side of the screen so that the aperture ratio of the display surface is not extremely reduced. What is necessary is just to form a black matrix.
[0030]
In FIG. 1, a position detecting means 6 is provided on the screen 5. FIG. 5 shows a typical configuration of the position detecting means.
FIG. 5 (A) shows an elastic translucent substrate having a plurality of strip-shaped translucent electrodes made of ITO (indium tin oxide) or the like on the surface thereof, which are superposed via a spacer such that the electrodes are orthogonal to each other. It is a thing. When pressure is applied to a specific location from the substrate surface, the opposing strip electrodes at that point come into contact and conduct. A current is sequentially applied to the opposing strip-shaped translucent electrodes and scanning is performed to detect the position of the conduction point.
[0031]
In FIG. 5B, a light-transmitting electrode is formed on substantially the entire inner surface of the opposing elastic light-transmitting substrate, and terminals are provided at both ends in the lateral direction of one substrate with respect to the light-transmitting electrode. On the other substrate, terminals are provided at both ends in the vertical direction and are opposed to each other via a spacer.
[0032]
When pressure is applied to a specific portion from the substrate surface as in the case of the position detecting means in FIG. 5A, the electrodes facing each other at that point come into contact and conduct. At this time, the position of the conduction point can be detected by measuring the resistance value between both terminals on both substrates.
Polyethylene terephthalate or the like can be used for the substrate as the position detecting means in FIGS. 5A and 5B. One of the substrates may be a glass or plastic plate.
[0033]
FIG. 5C shows an example in which an electric field is applied to an input pen in which a coil is wound around a tip of a pen such as a glass or plastic, and a magnetic field generated by the input pen causes a gap between the input pen and a transparent electrode provided on a light-transmitting substrate. It is possible to generate information on the position where the input has been performed by the electromagnetic induction effect generated in the above.
[0034]
The position detecting means in FIGS. 5A and 5B is provided on the front side (viewing side) of the screen. If the material of the screen is flexible, it may be provided on the back surface of the screen. The position detecting means in FIG. 5C may be on the back side or the front side of the screen as long as the input position can be detected.
[0035]
In addition, by providing an infrared light source and an infrared sensor on both sides of the screen as shown in FIG. 5 (D) as a position detecting means, the position where the infrared light is blocked by some shield is input. It can be detected as a position. Input can be performed on the display surface with a finger or the like.
[0036]
In any case, the information on the position on the screen input from the position detecting means as described above is input to a drive circuit of the liquid crystal electro-optical device or a computer connected thereto, and an image corresponding to this information is displayed on the screen. Displayed above.
[0037]
In order to accurately correspond the position on the screen 5 detected by the position detecting means to the image displayed by the liquid crystal electro-optical device 3, the image from the liquid crystal electro-optical device is shifted to the position detecting means on the screen. There is a need for a method for forming an image without any problem. As an example, an alignment pixel different from the display pixel is formed on the display surface of the liquid crystal electro-optical device, and a similar alignment marker is formed at a corresponding position on the screen to actually display an image. Before the adjustment, the tilt angle of the liquid crystal electro-optical device, the focal point of the lens of the optical system, and the like may be adjusted so that the light transmitted through the alignment pixel matches the marker on the screen. The alignment may be performed at specific pixels (for example, at the center and four corners of the display unit) of the display unit of the liquid crystal electro-optical device.
[0038]
FIG. 2 shows another conceptual diagram of the information input / output device of the present invention.
Further, as shown in FIG. 2, an imaging device 8 may be provided in the main body 1 to serve as a position detecting unit. In this case, light may be emitted from the front side to the back side of the screen 5 using a light emitting pen or the like, and the position may be detected by the imaging device 8. By doing so, even if the screen is large, it is only necessary to adjust the optical system to cope with the size, and it is not necessary to change the size of the light receiving surface of the imaging device 8 itself.
[0039]
Therefore, it is extremely easy to deal with a large screen as compared with the position detection means using a substrate having a size similar to a screen as shown in FIGS. Furthermore, by using an object having a high screen resolution for the imaging device itself, the resolution can be easily increased. Further, when the light emission color of a light irradiation device such as a light emitting pen is changed, it is possible to detect a difference in light emission color (a difference in light wavelength) by providing a color filter in the imaging device.
[0040]
Therefore, an image is displayed on a large area screen large enough to be viewed by many people, and information is directly input on the screen (screen) with a light emitting pen or the like, and a display corresponding to the information is performed. It can be used and can be an electronic blackboard that replaces conventional blackboards and whiteboards. Of course, a computer or the like may be used to perform calculations, character recognition, and the like based on the input information.
[0041]
As the imaging device, a charge-coupled device (CCD) or a photoconductive device can be used.
In FIG. 2, a half mirror 7 is provided between the optical system 4 and the liquid crystal electro-optical device 3, and light incident from the front side to the back side of the screen is made incident on the imaging device 8 through the optical system 4 to be read. I have. Of course, light entering the imaging device 8 from the front side to the back side of the screen may be read using an optical system different from the optical system 4.
[0042]
Alternatively, the screen 5 may be variably controlled so as to have high translucency from a light scattering state, and a document, an object, or the like existing on the front side of the screen may be read as an image. A light illuminating the document for reading may be provided in the main body 1. That is, the imaging device 8 is used as an image sensor.
The read image information can be stored in a storage device and displayed on a screen.
[0043]
It is also possible to use a method of instantly inputting and outputting an image having a huge amount of information.
In order to variably control the screen 5 between the light-transmitting state and the scattering state, a liquid crystal material is sandwiched between a pair of light-transmitting substrates having electrodes as the screen 5, and the screen 5 is switched between the transmission and scattering states by an electric field applied between the electrodes. May be used. In this case, when an image is displayed on a screen, the image may be in a scattering state, and when an image is read from the outside, the image may be in a transmission state. A ferroelectric liquid crystal electro-optical device or a polymer dispersed liquid crystal electro-optical device may be used.
Examples will be described below.
[0044]
【Example】
[Example 1]
FIG. 1 shows the configuration of the information input / output device of this embodiment. Light from the halogen lamp 2 is incident on a liquid crystal electro-optical device 3 provided in the main body 1 and displaying an image, and the light transmitted through the liquid crystal electro-optical device 3 is enlarged through an optical system 4 and projected on a screen 5. , The image is projected on the screen 5. A position detecting means 6 is provided on the screen 5, and when an input pen (not shown) is brought into contact with the screen, a signal corresponding to coordinates on the screen is transmitted to the drive circuit of the liquid crystal electro-optical device. And a signal corresponding to the input signal is output from the driving circuit to the display device.
[0045]
FIG. 6 shows a conceptual diagram of a liquid crystal electro-optical device manufactured according to this example. The liquid crystal electro-optical device is an active matrix driving type in which a switching element formed of a crystalline thin film transistor (TFT) is formed for each pixel. Further, a monolithic configuration in which a peripheral driving circuit for driving the liquid crystal electro-optical device is provided on the same substrate is also provided.
[0046]
Hereinafter, a manufacturing process of the thin film transistor is illustrated in FIGS. FIG. 3 is a cross section of a portion shown by a dashed dotted line in FIG. First, a silicon oxide film having a thickness of 100 to 300 nm, for example, 200 nm was formed as a base oxide film 202 on a substrate (Corning 7059, diagonal 1.6 inches) 201. As a method of forming the oxide film, a sputtering method in an oxygen atmosphere was used. However, in order to further improve mass productivity, a film in which TEOS is decomposed and deposited by a plasma CVD method may be used.
[0047]
Thereafter, an amorphous silicon film was deposited in a thickness of 30 to 500 nm, preferably 50 to 100 nm by a plasma CVD method or an LPCVD method, and was left in a reducing atmosphere at 550 to 600 ° C. for 24 hours to be crystallized. This step may be performed by laser irradiation. Then, the silicon film crystallized in this manner was patterned to form island-like active layer regions 203 and 204. Further, a silicon oxide film 205 having a thickness of 70 to 150 nm was formed thereon by sputtering.
[0048]
Thereafter, an aluminum film (containing 1 wt% Si or 0.1 to 0.3 wt% Sc) having a thickness of 100 nm to 3 μm, for example, 600 nm was formed by electron beam evaporation or sputtering. Then, a photoresist (for example, OFPR800 / 30cp, manufactured by Tokyo Ohka) was formed by spin coating. If an aluminum oxide film having a thickness of 10 to 100 nm is formed on the entire surface of the aluminum film by anodic oxidation before forming the photoresist, adhesion to the photoresist is good, and By suppressing the current leakage, it was effective in forming the porous anodic oxide only on the side surface in the subsequent anodic oxidation step. Thereafter, the photoresist and the aluminum film were patterned and etched together with the aluminum film to form wiring portions 206 and 209 and gate electrode portions 207, 208 and 210. (FIG. 3 (A))
[0049]
The photoresist is left on these wirings and gate electrodes, and functions as a mask for preventing anodic oxidation in a subsequent anodic oxidation step. FIG. 4 shows this state viewed from above. Also in this case, as in the first embodiment, the gate electrodes 207 and 208 and the wiring 209 are electrically independent from the wiring 206 and the gate electrode 210, and the former is referred to as an A series and the latter as a B series. (FIG. 4A)
[0050]
Then, of the above wirings and gate electrodes, only the B series is anodized by passing an electric current in an electrolytic solution, and the anodic oxides 211 and 212 having a thickness of 300 nm to 25 μm, for example, 0.5 μm, are formed by wiring and gate electrodes. Formed on the side. The anodization was performed using a 3 to 20% aqueous solution of citric acid or oxalic acid, phosphoric acid, chromic acid, sulfuric acid, or the like, and a constant current of 5 to 30 V, for example, 8 V, was applied to the gate electrode. The anodic oxide thus formed was porous. In this example, the voltage was set to 8 V in the oxalic acid solution (30 to 80 ° C.), and the anodization was performed for 20 to 240 minutes. The thickness of the anodized oxide was controlled by the anodizing time and temperature. At this time, no anodic oxide was formed on the gate electrodes 207 and 208 and the wiring 209 because no current was passed through the A series. (FIG. 3 (B), FIG. 4 (B))
[0051]
Next, the mask was removed, and a current was again applied to the gate electrode and wiring in the electrolytic solution. In this case, using an ethylene glycol solution having a pH of 7 containing 3 to 10% tartaric acid, boric acid, and nitric acid, electricity was supplied to both the A series and the B series. A better oxide film was obtained when the temperature of the solution was lower than room temperature around 10 ° C. For this reason, barrier type anodic oxides 213 to 217 were formed on the upper surfaces and side surfaces of the gate electrodes / wirings 206 to 210. The thickness of the anodic oxides 213 to 217 is proportional to the applied voltage. For example, an anodic oxide having an applied voltage of 100 V and a thickness of 120 nm was formed. In this example, since the voltage was increased to 100 V, the thickness of the obtained anodic oxide was 120 nm. The thickness of the barrier type anodic oxide is arbitrary, but if it is too thin, there is a risk that aluminum will be eluted when the porous anodic oxide is etched later. .
[0052]
It should be noted that although barrier-type anodic oxide can be obtained in a later step, a barrier-type anodic oxide is not formed outside the porous anodic oxide, but instead of porous anodic oxide. A barrier-type anodic oxide is formed between the gate electrodes. (FIG. 3 (C))
Thereafter, an impurity is implanted into the active layers 203 and 204 of the TFT in a self-aligned manner using the gate electrode portion (that is, the gate electrode and the anodic oxide film around the gate electrode) and the gate insulating film as a mask by ion doping, and the impurity (source) is formed. / Drain) regions 218, 219 and 220 were formed. Phosphine (PH ₃ ) And diborane (B ₂ H ₆ ) Was used. Dose amount is 5 × 10 ¹⁴ ~ 5 × 10 ^Fifteen cm ^-2 , And the acceleration energy was 50 to 90 keV. Impurities are introduced so that the regions 218 and 220 become N-type and the region 219 becomes P-type. The region 218 forms the NTFT 228, the region 219 forms the PTFT 229, and the region 220 forms the NTFT 230.
[0053]
As a result, in the two TFTs 228 and 229 on the left side of the figure (these are complementary TFTs), since the thickness of the anodic oxides 214 and 215 on the side surfaces of the gate electrode is about 120 nm, the gate electrode and the impurity region Of non-overlapping area (offset area) x ₁ , X ₃ Was about 100 nm in consideration of the wraparound during ion doping. On the other hand, in the TFT 230 on the right side, since the total thickness of the anodic oxides 212 and 217 is about 620 nm, the offset width x ₂ Was about 600 nm.
[0054]
Thereafter, the porous anodic oxides 211 and 213 were etched using a mixed acid of phosphoric acid, acetic acid, and nitric acid. In this etching, only the anodic oxides 211 and 213 were etched, and the etching rate was about 60 nm / min. The barrier type anodic oxides 213 to 217 and the silicon oxide film 205 remained as they were. Thereafter, irradiation with a KrF excimer laser (wavelength: 248 nm, pulse width: 20 nsec) was performed to activate the impurity ions introduced into the active layer. (FIG. 3 (E))
[0055]
Then, the gate electrode and the wiring were divided to have the required size and shape. (FIG. 4C).
Further, a silicon oxide film having a thickness of 600 nm was formed as an interlayer insulator 221 over the entire surface by a CVD method. Next, an ITO film having a thickness of 80 nm was formed by a sputtering method, and this was patterned to form a pixel electrode 222. Then, the interlayer insulator 221 and the gate insulating film 205 are etched to form contact holes in the source / drain of the TFT, and at the same time, the interlayer insulator 221 and the anodic oxides 213 to 217 are etched to form a gate electrode / wiring. A contact hole was formed. In this embodiment, since the anodic oxide has substantially the same thickness in both the A-series and the B-series, they can be etched simultaneously. Finally, aluminum wiring / electrodes 223 to 226 were formed, and hydrogen annealing was performed at 200 to 400 ° C.
[0056]
Note that the wiring 223 connects the wiring 206 to the source of the N-channel TFT of the complementary TFT, and the wiring 225 connects the source of the P-channel TFT of the TFT of the complementary TFT to the wiring 209. The wiring 224 (that is, 226) connects the output terminal of the complementary TFT (that is, the drain of the N-channel TFT and the drain of the P-channel TFT) to the drain of the right TFT. Further, the wiring 227 connects the drain of the right TFT and the pixel electrode 222. Thus, an integrated circuit having a TFT is completed. (FIG. 3 (F))
[0057]
Also, particularly in the A series, as shown in the embodiment, the driver is driven by a large current, so that the PTFT (the width of the high resistance region is x ₁ ), NTFT (the high resistance region width is x ₄ ) And there is little deterioration. Further, a decoder, a CPU, a shift register, a memory, and other driving circuits consume low power and operate at high frequency, so that both channel width and channel length are small, and deterioration due to hot carriers is likely to occur. The width x of the high resistance region of the NTFT used in these circuits ₃ Is the width x of the high resistance region of the PTFT ₁ It needs to be bigger. In addition, NTFT in the active matrix circuit to which a large voltage is applied (the width of the high resistance region is x ₂ ), The required mobility is also small, so that deterioration is very likely to occur. As a result, x ₂ > X ₃ > X ₄ ≧ x ₁ Is required. For example, x ₂ Is 0.5-1 μm, x ₃ Is 0.2-0.3 μm, x ₄ Is 0 to 0.2 μm, x ₁ Is from 0 to 0.1 μm. Thus, the shift register could operate at 1 to 50 MHz.
In the present embodiment, the effect of suppressing the leak current when the width of the offset of the TFT (right TFT) for controlling the pixel electrode is sufficiently large is great.
[0058]
Next, in FIG. 6, a transparent electrode 302 made of ITO was formed on the entire surface of the opposing substrate 301.
Next, an alignment film 303 made of polyimide was formed as an alignment film on the substrates 201 and 301.
Next, the alignment film was rubbed by an ordinary method. At this time, the rubbing direction was such that the upper and lower substrates formed an angle of 90 °.
Next, a spacer made of silicon oxide having a diameter of 5 μm was sprayed on the substrate coated with the alignment film of the substrate (not shown).
Next, a sealant (not shown) was printed on the substrate 201, and the substrates 201 and 301 were overlapped and fixed.
Next, a liquid crystal material 304 was injected into the cell by a vacuum injection method. The liquid crystal material used was a nematic liquid crystal ZLI-4792 (trade name) manufactured by Merck.
Thus, the liquid crystal electro-optical device 3 of FIG. 1 was formed. The number of pixels was 640 × 480. The number of pixels may be 1280 × 1024.
[0059]
As the light source 2, a metal halide lamp was used. The output of the light source was 250 W, and the ambient temperature of the liquid crystal electro-optical device was 50 ° C.
The screen 5 used was 800 × 600 mm. An optical system including a lens, a mirror, and the like was provided.
Next, on two polyethylene terephthalate substrates of about the same size as the screen and having a thickness of 0.5 mm, a transparent electrode made of ITO was formed on the upper surface of the substrate by a normal process, and the two substrates were overlapped to form a transparent electrode as shown in FIG. The patterning shown in FIG. A protective film made of polyethylene terephthalate was formed on the electrode surface. The position detecting means 6 is completed. The matrix size of the transparent electrode was 640 × 480, which is the same as that of the liquid crystal display device.
Thus, the information input / output device shown in FIG. 1 was completed.
[0060]
The input pen is shown on the lower side of FIG. The input pen is made of acrylic, glass, or the like, and has a coil wound at one end.
An electric field is applied to the electrodes formed on the screen, and the electric field is also applied to the input pen. When the input pen is brought into contact with an arbitrary position on the screen, the interaction between the magnetic field generated from the input pen coil and the electric field applied to the transparent electrode on the screen causes the input pen to touch Since the current value is different between the above-mentioned portions, the portion where the pen is in contact is detected from the current detection circuits formed for each matrix. Next, a signal relating to coordinates at which the pen of the screen is in contact with the drive circuit is input from the current detection circuit, and a signal relating to the coordinates is input from the drive circuit to a display signal on a matrix having the same coordinates as the coordinates of the liquid crystal electro-optical device. Is output. As a result, an image is displayed on the screen at the position where the input pen is touched.
[0061]
When drawing characters with an input pen, the liquid crystal display device may be driven so as to maintain the display contents changed after the pen touches.
Further, a black matrix was formed on the screen. This makes it possible to display the outline of the dot without being blurred due to diffraction.
[0062]
[Example 2]
In the second embodiment, an information input / output device was manufactured in which the position detection means 6 of the information input / output device manufactured in the first embodiment was changed to a device using an infrared sensor.
As shown in FIG. 5D, an infrared ray source 501 and an infrared ray sensor 502 are arranged on the vertical and horizontal edges of the screen 5. The infrared sensor 502 has a triangular shape with an opening of 3 mm at the bottom and 5 mm in height, and is formed at 1 cm intervals on each side in the vertical and horizontal directions. On the other side, an infrared light source was provided corresponding to the infrared sensor 501.
[0063]
When a finger or a pen is brought into contact with an arbitrary position on the screen, infrared rays corresponding to the coordinates are blocked, and light does not reach the sensor. By arranging the infrared source and the sensor in the vertical and horizontal directions as in the present embodiment, the position where the finger or the like is placed can be detected as the vertical and horizontal coordinates. By inputting the coordinate signals detected in this way to the drive circuit of the liquid crystal display device and inputting a signal for changing the display state to the same coordinates of the matrix of the liquid crystal display device, information is input on the screen. Can be shown.
[0064]
In addition, a black matrix surrounding each pixel was formed on the screen. This makes it possible to display the outline of the pixel without blurring due to diffraction.
[0065]
[Example 3]
In the third embodiment, an information input / output device in which the position detection means 6 of the information input / output device manufactured in the first embodiment is replaced with a touch panel shown in FIG.
For the touch panel, a plurality of stripe-shaped transparent electrodes made of ITO (indium tin oxide) are formed on an 800 × 600 mm polyethylene terephthalate substrate having elasticity, and rubber spacers having a diameter of 40 μm are formed on this substrate at a pitch of 300 μm vertically and horizontally. Further, a polyethylene terephthalate substrate on which a plurality of stripe-shaped transparent electrodes made of ITO were formed and laminated so that the electrodes were orthogonal to each other was used. When the touch panel was pressed with a finger or a pen or the like, the upper and lower substrates were brought into contact, and an input signal could be generated at a position corresponding to the pressed portion on the matrix formed by the stripe electrodes.
[0066]
This coordinate signal was connected to a touch panel so as to be input to a drive circuit or a computer circuit of the liquid crystal display device, and a point could be displayed on the screen 5 at a position where pressure was applied with a pen or the like. In addition, moving the position where pressure was applied could draw a line. When a button is displayed on the screen and pressure is applied to the button, it becomes possible to delete the function of the button, for example, to delete all the displayed contents.
Thus, the tablet could be configured on the screen.
[0067]
In addition, a black matrix surrounding each pixel was formed on the screen. This makes it possible to display the outline of the pixel without blurring due to diffraction.
[0068]
[Example 4]
In the fourth embodiment, in the information input / output device manufactured in the third embodiment, the liquid crystal electro-optical device 3 is composed of three shutter liquid crystal electro-optical devices using ferroelectric liquid crystal and an active matrix type liquid crystal electro-optical device using ferroelectric liquid crystal. It was composed of a liquid crystal electro-optical device for image display.
[0069]
The liquid crystal material used for the liquid crystal electro-optical device for a shutter will be described. The liquid crystal material is a phenylpyrimidine-based ferroelectric liquid crystal, and its phase series is Iso-SmA-SmC. ^* And its phase transition temperature is 85 ° C. for Iso-SmA and SmA-SmC ^* Was 55 ° C. The magnitude of spontaneous polarization is 20 nC / cm ² Met.
[0070]
A cell was formed by opposing a light-transmitting substrate having a light-transmitting electrode formed on the entire surface thereof via a spacer and a sealing material, and the liquid crystal was injected into the cell at a temperature indicating an Iso phase. Further, the panel was gradually cooled from this temperature to room temperature at a rate of 5 ° C./hr in order to obtain a favorable alignment state. The contrast of the panel at room temperature was 80 when measured by driving with a voltage of ± 20 V and a rectangular wave of 5 Hz.
Three liquid crystal electro-optical devices for shutters were produced corresponding to red (R), green (G), and blue (B).
[0071]
The liquid crystal electro-optical device for image display is an active drive type liquid crystal electro-optical device having a structure shown in FIG. 6, in which anti-parallel rubbing is performed on both substrates, and a space between substrates is maintained by a spacer having a diameter of 1.6 μm. The same ferroelectric liquid crystal material as that used in the liquid crystal electro-optical device for shutter was injected into the liquid crystal cell between the substrates in the same process.
[0072]
Next, FIG. 7 shows a liquid crystal electro-optical device according to this embodiment. Light from the light source is split into three types by a half mirror and is incident on a shutter that displays red, green, and blue. A shutter is driven from the outside so as to show a desired display color, and light transmitted through the shutter is mixed by a half mirror and is incident on an image display panel. The transmitted light 700 transmitted through the image display panel passes through an optical system and irradiates the screen to perform color display on the screen.
[0073]
The shutter is turned on for red in the first period, turned on for green in the second period, turned on for blue in the third period, and sequentially turned on in the time series according to the three primary colors of light. The color supplied to one device was changed.
As a result, three-color, eight-step gradation display, that is, display of 512 colors is made possible. A position detecting device 6 using translucent electrodes arranged in a matrix similar to that shown in Example 3 was used.
[0074]
In addition, a black matrix surrounding each pixel was formed on the screen. This makes it possible to display the outline of the pixel without blurring due to diffraction.
[0075]
[Example 5]
FIG. 2 shows the information input / output device of this embodiment.
In this embodiment, an image pickup device 8 that receives light incident from the front side to the back side of the screen 5 is provided inside the main body 1, that is, on the back side of the screen 5. The size of the screen was 1000 × 750 mm.
[0076]
Here, a charge-coupled device (CCD) capable of reading color is provided as the imaging device 8. Although not shown, an optical system different from the optical system 4 was used to receive light incident on the screen 5. The optical system 4 and the half mirror 7 may be used.
In this optical system, a filter that transmits only light having a certain level of brightness or more may be provided.
[0077]
The signal of the incident light read by the imaging device is connected so as to be input to a computer circuit (not shown).
An output image from the computer circuit is displayed on the liquid crystal electro-optical device 3, enlarged by the light source 2 and the optical system 4, and projected on a screen 5.
[0078]
When the light-emitting pen contacts the screen, it is turned on and emits light of a specific color toward the back of the screen (inside the body). Here, a pen capable of emitting any one of three colors of red, blue, and green toward the back side of the screen 5 was used.
[0079]
When a specific location on the screen 5 (front side) was designated using a light emitting pen set to emit red light, red light was emitted toward the back side of the screen 5.
The emitted red light enters the imaging device 8 through the optical system, detects the position on the screen and the emission color in the imaging device 8, and transmits the information signal to a computer circuit or a driving circuit of the liquid crystal electro-optical device 3. It was transmitted to.
[0080]
A dot was displayed on the screen 5 in red in the same color as the light emission color of the light emitting pen. When the light-emitting pen was moved on the screen 5, a line was displayed in red according to the trajectory. Similarly, when the color of the light-emitting pen is green, a point or a line is displayed in green when the color is green, and in blue when the color is blue. As a matter of course, here, the driving method and programming are performed so that the color of the incident light and the displayed color are the same.
One or more button-shaped areas may be displayed on a part of the display screen, and a setting can be made such that when the area is indicated by a light emitting pen, the display state is greatly changed.
When not only points and lines but also two points on the screen are designated, for example, a rectangle whose diagonal line is indicated may be displayed, or the area may be filled with a specific color.
Further, when a character is input, the input character may be recognized and a well-formed character incorporated in a computer circuit corresponding to the input character may be displayed.
In addition, various applications such as spreadsheets and graphic drawing are possible.
[0081]
In addition, since the information input / output device of the present embodiment has a sufficiently large screen, a large number of tens to hundreds of people can visually recognize characters and figures drawn on the screen 5 using the light emitting device. , Could be used like an electronic blackboard.
[0082]
Further, a black matrix surrounding the periphery of each pixel may be formed on the screen 5.
[0083]
[Example 6]
In the present embodiment, a configuration in which a document or an object existing on the front side of the screen 5 is read as image data by the imaging device 8 in the information input / output device shown in FIG. The same liquid crystal electro-optical device, optical system, and light source as in Example 1 were used.
In order to read a document or an object on the front side of the screen 5 as image data, it is necessary to variably control the state in which the screen 5 transmits light and the state in which light is scattered. As a configuration of the screen 5 suitable for this, a scattering mode ferroelectric liquid crystal electro-optical device or a polymer dispersed liquid crystal electro-optical device can be used.
[0084]
In the scattering mode ferroelectric liquid crystal electro-optical device, the transmittance can be increased to about 90% without using a polarizing plate, and the scattering state can be changed by applying an electric field. The polymer dispersed liquid crystal electro-optical device also has a transmittance of 80% or more, and the same effect can be obtained.
Here, a scattering mode ferroelectric liquid crystal electro-optical device was used as the screen 5.
[0085]
Two 800 × 600 mm substrates having a translucent electrode provided on the entire surface of one surface are provided facing each other with a 50 μm diameter spacer and a sealing material with the electrode surface inside. And a ferroelectric liquid crystal was injected into the cell to form a liquid crystal electro-optical device serving as the screen 5.
[0086]
An information input / output device was constructed using this screen, and an image on the front side of the screen 5 was read.
Further, in order to improve the quality of the read image, a light for irradiating a subject such as a document is provided in the main body 1.
[0087]
First, an original on which a drawing is drawn is attached to the front side of the screen 5, and when a DC voltage is applied between the electrodes of both substrates of the liquid crystal electro-optical device constituting the screen 5, the screen 5 has 90% transmittance. Became transparent.
The light was irradiated toward the original by the light, and the reflected light was read by the imaging device 8, and the image data was stored in the storage device.
[0088]
Subsequently, an AC voltage was applied to the liquid crystal electro-optical device constituting the screen 5 to make the screen 5 in a scattering state, and the image data previously read and displayed on the liquid crystal electro-optical device 3 was displayed on the screen.
In the apparatus of the present embodiment, the object to be read by the imaging device 8 is not only a document on the screen 5 but also a subject existing on the front side of the screen 5, for example, an image displayed on the screen 5 by modifying the optical system. It is also possible to read the face of the viewer and display it on the screen at the next moment.
[0089]
Further, the position detecting means 6 may be provided on the screen 5.
Further, a black matrix surrounding the periphery of each pixel may be formed on the screen 5.
[0090]
【The invention's effect】
As described in detail above, according to the present invention, a pen, a finger or the like instructs on the screen of the projection type liquid crystal electro-optical device, inputs information on the position on the screen, and displays the display contents of the liquid crystal electro-optical device. An information input / output device that can be changed can be provided.
[0091]
Further, according to the present invention, the display content of a display device that displays an image on a large-area screen large enough to be viewed by many people is changed by information directly input on the display surface. An information input / output device that allows the information to be input is provided.
[0092]
Further, the information input / output device can detect a position pointed by a pen or the like on the screen and display corresponding to the position without impairing the quality of an image projected on the screen.
[0093]
Further, it has become possible to read a document or a subject existing on the front side of the screen as image data.
[0094]
As described above, according to the present invention, it is possible to input information on a screen with the same feeling as writing a character or a picture on paper.
[Brief description of the drawings]
FIG. 1 shows an example of a conceptual diagram of an information input / output device of the present invention.
FIG. 2 shows an example of another conceptual diagram of the information input / output device of the present invention.
FIG. 3 illustrates a manufacturing process of a thin film transistor.
FIG. 4 illustrates a manufacturing process of a thin film transistor.
FIG. 5 shows a typical configuration of a position detecting means.
FIG. 6 is a conceptual diagram of a liquid crystal electro-optical device manufactured in an example.
FIG. 7 shows a configuration of a liquid crystal electro-optical device in an embodiment.
[Explanation of symbols]
1 body
2 Light source
3 Liquid crystal electro-optical device
4 Optical system
5 screen
6 Position detection means
7 Half mirror
8 Imaging device
201 substrate
222 pixel electrode
230 thin film transistor
301 substrate
302 Counter electrode
303 alignment film
304 liquid crystal material
501 Infrared source
502 Infrared sensor
700 transmitted light

Claims (5)

A display device, a screen, a first optical system that projects an image of the display device onto the screen, an imaging device, and a second optical device that emits light from the screen to the imaging device inside the main body. Having a system,
Detecting the position on the screen where the light amount has changed by the imaging device,
A projection display device that rewrites an image of the display device corresponding to a position detected by the imaging device,
The screen is a liquid crystal electro-optical device,
When controlling the liquid crystal electro-optical device in a state where light is transmitted through the screen, the imaging device reads an optical image incident on the non-display surface side of the screen from a subject present on the display surface side of the screen. Performed, the read image is displayed on the display device inside the main body,
By controlling the liquid crystal electro-optical device in a state where light is scattered on the screen, the read image is displayed on the screen,
A pen having a light-emitting function causes light to be incident on a specific position on the screen from a display surface side of the screen to a non-display surface side to change the amount of light at a specific position on the screen,
A projection display device, wherein a position on the screen at which the light amount changes is detected by the imaging device, and an image of the display device corresponding to the position detected by the imaging device is rewritten. 2. The projection display device according to claim 1, wherein the imaging device is a photoconductive element. 2. The projection display device according to claim 1, wherein the imaging device is a charge-coupled device. 4. The projection display device according to claim 1, wherein the display device has an active matrix liquid crystal display device and a light source. The projection type display device according to claim 1, wherein a black matrix is provided on the screen.

Images