JP2000020011A - Picture display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device in which suppressing power consumption, making the device thin, making it high definition, and making it large screen can be easily performed and for which the installation place is not limited. SOLUTION: Picture information 11 is encoded (digitized) by a picture information coding section 12, and a digitized signal is outputted from an optical signal emitting sectional 12 as an optical pulse signal. In an optical signal receiving section in a display unit 15, a received optical signal is converted to an electric signal and outputted to a control sections 17. And in the control section 17, an inputted signal is decoded, and display is performed by controlling a display section 18 in accordance with the decoded signal. And plural display units 15 form a multiple display device in which matrix arrangement is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device which can be easily made large and thin.

[0002]

[Prior Art] In recent years, full-scale development of advanced information society,
2. Description of the Related Art With the rapid spread of multimedia and advanced electronic systems, the importance of electronic image display devices, which play a bridging role between humans and various devices, is increasing, and the needs thereof are steadily expanding.

[0003] In particular, an image display device having a large screen, color, and high definition in three beats has an excellent eye-catching effect, a large amount of information, and is used for a system as a multimedia terminal, an outdoor signboard, an indoor signage. Its demand, including for display purposes, is steadily increasing in the future.

A conventional large-sized display device and its driving method are as follows.
It is roughly divided into an electronic system and a mechanical system. The former is naturally capable of displaying a large amount of information at high speed. Further, electronic image display devices can be broadly classified into a direct-view type and a projection type.

[0005] The projection type image display device has an advantage that a large screen can be easily obtained.
Partly used as HP. However, it is difficult to obtain the brightness, and naturally it is limited to indoor use. Further, since the projection is performed, there is a difficulty that the light-shielding object is not allowed in the projection space and the projection space is occupied.

Further, if the angle between the screen and the projector facing the projector is shifted, the image itself is distorted, so that a strict restriction is imposed on the positional relationship between the screen normal and the projector. In addition, when the distance between the projector and the screen is short, it is difficult to manufacture an optical system having a high magnification. Further, since the pixels themselves are enlarged by projection, it is extremely difficult to display a high-definition large screen.

In order to avoid these difficulties, it is necessary to use a direct-view image display device that can be used indoors and outdoors. These direct-view image display devices are roughly classified into a light-emitting type and a light-receiving type.

As a light emitting type image display device, a plasma display panel (PDP) utilizing a discharge phenomenon is known. However, because of the use of the discharge phenomenon,
The driving voltage is as high as about 100 V, and the power consumption increases. Therefore, there is a major obstacle to making the driving IC into an LSI. In particular, this problem becomes remarkable when realizing a large-screen, high-definition, color image display.

Further, in order to display a high definition image,
A high-density electric wiring for driving a pixel must be formed over a large area, and since each pixel is driven through a long-distance wiring, a high driving force is required for a driving circuit.

A cathode ray tube display (CRT) utilizing phosphor excitation light emission by electron beam scanning has been well known. However, this type of image display device is physically large and compact. Therefore, it is difficult to display a thin large screen. Further, the need for a high drive voltage is the same as that of the PDP.

As another light emitting type image display device, one using a light emitting diode (LED) is known. However, in order to get a full color display, red,
Since each pixel must be configured by combining different LEDs for emitting blue and green light, it is difficult to achieve high definition.

On the other hand, as a light receiving type image display device, a liquid crystal display (LCD) utilizing a change in optical properties of liquid crystal is known. It is also possible to provide the pixels with memory properties, and if a reflective liquid crystal display is used, the energy required for display light emission is unnecessary, so that power consumption is reduced. However, in order to display a high-definition image, it is necessary to form a high-density pixel drive wiring over a large area, and it is extremely difficult to manufacture these collectively. Further, there is a need to obtain a conductive wiring over a long distance without a defect, and the yield is reduced.
In addition, since each pixel is driven through a thin line over a long distance,
A high driving force is required for the driving circuit.

[0013]

As described above, the projection-type image display device can easily be enlarged in screen size, but does not allow any obstacles in the projection space and the installation place is limited. was there. Further, the PDP has a problem that power consumption is high because an image is displayed using a discharge phenomenon. In addition, there is a problem that it is difficult to reduce the thickness when forming a large-screen CRT. In addition, LCD
There is a problem that it is difficult to form a high-density pixel driving wiring over a large area. SUMMARY OF THE INVENTION An object of the present invention is to facilitate low power consumption, thin, high definition, and large screen,
An object of the present invention is to provide an image display device whose installation place is not limited.

[0014]

Means for Solving the Problems [Configuration] The present invention is configured as follows to achieve the above object. (1) An image display device according to the present invention (claim 1) includes an optical signal emitting unit that sends out an optical signal corresponding to image information, an optical signal receiving unit that receives the optical signal, and an optical signal receiving unit that receives the optical signal. A display unit including a control unit for demodulating / decoding image information and a display unit for displaying in accordance with the image information is provided, and a plurality of the display units are arranged in a matrix.

The optical signal includes a signal obtained by digitizing the image information. Each display unit is given unique address information. A light receiving surface on which the optical signal light receiving unit receives the optical signal faces in the same direction as a surface of the display unit on which an image is displayed.

[0016] The optical signal emitting section transmits an optical signal including at least the address information given to the display unit and image information corresponding to the display unit. In this way, an arbitrary display unit can be displayed.

Preferred embodiments of the present invention are shown below.
A display control unit is formed below the display device, and installs a driving electronic circuit around the image display unit.

A transparent electrode formed on the entire screen or an electrode formed on the back of the screen is used as a power supply electrode. There is no need for electrical wiring across the entire screen other than the transparent electrodes formed on the entire screen and the electrodes formed on the back of the screen.

The image display section is composed of a plurality of pixels. A plurality of display units are formed on a single semiconductor substrate.

A plurality of image display devices are arranged on a flexible substrate. A plurality of image display devices are arranged and formed on a curved surface. The address information for self-recognition stored in the display control unit can be updated by an optical signal.

The display unit of the display unit is composed of one pixel, and the display unit is controlled by one corresponding display control unit. The display unit of the display unit includes one pixel, and is controlled by one or more display control units.

The light signal receiving section is a photodiode formed on a semiconductor substrate. The display unit is constituted by a reflective liquid crystal display. The optical signal is invisible light,
In particular, infrared light.

An optical signal is transmitted to an optical signal receiving unit using a semiconductor laser or a light emitting diode as a light emitting means of the optical signal emitting unit. A filter that transmits a specific wavelength is provided on the surface of the light receiving unit of the optical signal receiving unit.

An optical signal is transmitted by an optical signal having a plurality of wavelengths by using a plurality of optical signal receiving units provided with a plurality of filters. It is a special feature that at least one optical signal is an optical signal controlled by a viewer, and is superimposed on video information transmitted separately from the optical signal and displayed in real time.

The optical signal includes a signal indicating the luminance of the outside world and the like, and based on this information, the video information sent separately is adjusted and displayed in real time. The image display surface has a shape other than a rectangle.

A large-screen display is manufactured by arranging the same image display devices. By arranging the same image display device, displays of various different sizes are manufactured from the same manufacturing equipment.

A large-screen display is manufactured by arranging the same image display device so as to be detachable, and the defective image display device can be arbitrarily replaced. The transmission of the optical signal is performed by scanning the image display device with a light beam focused only on a part of the image display device.

The transmission of an optical signal is performed by irradiating a plurality of light beams focused only on a part of the image display device onto the image display device,
Perform all at once. The display control unit has a function of determining the update of the display content based on the display content light of the surrounding pixels in addition to the information based on the optical signal.

It is characterized in that the function of determining by analogy can be externally updated by an optical signal. [Operation] The present invention has the following operation / effect by the above configuration.

According to the present invention, display is performed by arranging a plurality of display units in a matrix, and the control of the display unit in each display unit is performed using the control unit connected thereto. In forming a high-definition image display device, it is not necessary to form high-density, long-distance electrical wiring over the entire screen, and a large driving force is not required for the driving circuit.

In addition, there is no need to form wiring between the display units. Therefore, when a large-screen display is formed by integrating image display devices on which a plurality of display units are formed, it is only necessary to mechanically arrange the image display devices. The image display devices can be manufactured separately, and those indicating a defect can be eliminated at the stage of integration. This alleviates the strict manufacturing constraints required to secure the final function of all pixels, which is required when a large-screen display is manufactured collectively, and leads to an improvement in yield.

Further, transmission of image information to the display unit is performed by an optical signal from an optical signal light emitting unit, and there is no need to provide a drive circuit around the image display device. Therefore, the number of pixels of the display unit can be basically set arbitrarily. Further, the shape of the pixel or the display portion can be arbitrary.

In forming a display having any screen size, the image display device can be manufactured by using the same manufacturing equipment, and it is not necessary to update the manufacturing equipment depending on the screen size.

In addition, by integrating the image display device on a curved substrate, a display can be formed on an arbitrary curved surface. In addition, by integrating the image display device on a flexible substrate, a flexible display can be manufactured.

If the display portion of the display unit is formed by a method such as a liquid crystal which allows a reduction in weight and thickness, a thin and large-screen display can be easily formed. By transmitting a pulsed digital signal as an optical signal, the display content does not change even if the spatial position between the optical signal light emitting unit and the image display unit is shifted.

Therefore, unlike the case of the projection type image device, the optical signal light emitting portion does not need to face the display device (screen), and as long as the light reaches the optical signal light receiving portion directly or indirectly, it is almost possible. They can be arranged arbitrarily. If an optical signal other than visible light is used, the display contents will not be disturbed. However, since there is no obstacle in the space in front of the display surface of the display unit that hinders the viewer's vision, the light receiving surface of the optical signal receiving unit and the display surface of the display unit must be in the same direction. Is preferred.

Since each display unit has a control unit attached thereto, a complicated control signal can be easily transmitted if various instruction codes are stored in this unit. Since control of each display unit is performed by an optical signal emitted from the optical signal light emitting unit, updating of the screen is not limited to the band-shaped line sequential scanning method, and update any display unit in any order. Is possible. Therefore, the image can be updated with a minimum update.

[0038]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram illustrating a schematic configuration of an image display device according to an embodiment of the present invention.

The image information 11 is encoded (digitized) by the image information encoding unit 12, and the digitized signal is output from the optical signal emitting unit 13 as an optical pulse signal. The optical signal receiving unit 16 in the display unit 15 converts the received optical signal into an electric signal and outputs the electric signal to the control unit 17. Then, the control unit 17 decodes the input signal and controls the display unit 18 according to the decoded signal to perform display.

The composite display device 14 has a plurality of display units 15 formed on the same substrate. The control unit 17 of each display unit 15 stores address information unique to each display unit 15. Then, as shown in FIG. 2, it is possible to configure a large-screen display 21 by arranging a plurality of composite display devices 14 in a matrix.

It should be noted that the image information encoding unit 12
After digitizing the image information 11 with a predictor based on the M (Differential Pulse Code Modulation) method, it is desirable to further compress the data by entropy coding based on a technique such as Huffman coding or arithmetic coding. . Then, the control unit 17 decodes the image information using the same predictor as the predictor used in the image method encoding unit 12 after decompressing through the entropy decoder.

As an optical signal oscillated from the optical signal light emitting section 13, it is desirable to use a wavelength in the infrared region near 0.8 μm where high quantum efficiency is obtained in the case of indirect transition type Si. Since light having a wavelength in the infrared region is invisible to the naked eye, the displayed image is not disturbed by the light pulse signal, which is convenient.

In order to generate an optical pulse signal having a wavelength in the infrared region, an optical signal having a wavelength in the infrared region can be transmitted by using, for example, a semiconductor laser having a heterostructure of AlGaAs / GaAs as a light source. become.
By changing the composition ratio of Al and Ga in AlGaAs of the active layer, the emission wavelength can be arbitrarily set in a wavelength region of 0.7 to 0.9 μm, and a pulse modulation speed of 1 Gb / s or more is possible.

In addition to the laser oscillator, it is possible to use an LED as a light emitting element. Although the light output is lower than that of a semiconductor laser, it is not necessary to localize a light source as a light emitting element. Therefore, a large number of surface emitting type LEDs may be integrated to increase the output of the light emitting element. LEDs can reduce optical noise compared to laser light having a high degree of coherence, and at the same time, are low in cost and highly reliable.

The number of pixels of the display section 18 may be singular or plural. However, when the number of pixels is one, the configuration of the control unit 17 can be simplified. A specific configuration of the display unit is shown in a cross-sectional view of FIG. An element isolation insulating film 3 for isolating an element region on a p-type silicon substrate 30
1 is formed. An n-type well 32 is formed in a part of the element region. Further, the n-type diffusion layers 35 (35a to 35g) are formed so as to sandwich the n-type gate electrode 34 formed on the p-type Si substrate 30 with the gate insulating film 33 interposed therebetween.
It is formed on the surface of the mold Si substrate 30. Further, the p-type diffusion layer 37 (37) is sandwiched so as to sandwich the p-type gate electrode 36 formed on the n-type well 32 via the gate insulating film 33.
a, b) are formed on the surface of the n-type well 32.

The p-type Si substrate 30 and the n-type diffusion layer 35
A photodiode is formed at the pn junction with a.
Further, the n-type gate electrode 34a is a gate electrode of the photodiode access MOSFET 38,
b is the gate electrode of the photodiode reset MOSFET 39, and the n-type gate electrode 34c is the n-type MOSFET 4
The gate electrode 0, the n-type gate electrode 34d is the gate electrode of the display electrode access MOSFET 42, and the p-type gate electrode 36 is the gate electrode of the p-type MOSFET 41.

Then, a first interlayer insulating film 43 is formed on the entire surface. In the first interlayer insulating film 43, plug electrodes 44 (44a to 44g) connected to the n-type diffusion layers 35c to 35g and the p-type diffusion layer 37 are formed, respectively.

The plug electrode 44 is formed on the first interlayer insulating film 43.
a lower reflector 45 connected to n-type diffusion layer 35c through a
Are formed. Further, on the first interlayer insulating film 43,
Contact electrode 4 connected to plug electrodes 44b, eg
6, 48 are formed respectively. Further, a wiring 47 connecting the plug electrode 44c and the plug electrode 44d is formed on the first interlayer insulating film 43.

Then, a second interlayer insulating film 49 is formed on the entire surface. The lower reflector 4 is formed on the second interlayer insulating film 49.
5 and a contact hole connected to the contact electrode 48, respectively, and a plug electrode 50 (50
a, b) are formed.

An upper reflector 51 connected to the lower reflector 45 via the plug electrode 50a is formed on the second interlayer insulating film 49. The upper reflector 51 and the lower reflector 45 form a Fabry-Perot = interference filter. A display electrode 52 connected to the contact electrode 48 via the plug electrode 50b is formed on the second interlayer insulating film 49.

A spacer insulating film 53 is formed on a part of the upper reflecting plate 51, the display electrode 52, and the second interlayer insulating film 49. On the spacer insulating film 53 formed on the upper reflector 51, a plug electrode 5 connected to the upper reflector 51 is formed.
4 are formed. Further, on the spacer insulating film 43,
A contact electrode 55 connected to the plug electrode and a dummy electrode 56 are formed.

Exposed upper reflector 51 and display electrode 52
A liquid crystal alignment layer 57 is formed thereon. A transparent electrode 58 is formed on the surface of the spacer insulating film 43 via electrodes 55 and 56.
The plastic substrate 59 on which is formed is provided.
The liquid crystal layer 60 is sealed in the space between the liquid crystal alignment layer 57 and the transparent electrode 58.

Then, a large-screen display is formed by arranging composite display devices each having a plurality of liquid crystal units formed on the same substrate. In addition, by arranging and installing a plurality of composite electronic devices on a flexible substrate,
A display having flexibility can be formed. As a flexible substrate, for example, a conductive rubber sheet or a metal sheet, which has both conductivity and a conductive adhesive, is used to obtain an electrical connection between the composite display devices. It is convenient.

The electrical connection between the transparent electrodes 58 includes:
By disposing and bonding a plastic sheet coated with indium oxide or tin oxide between the surfaces of the composite electronic device, the composite electronic devices can be arranged and arranged without being conscious of the joint portion, and a display can be configured.

After the display is constructed, the entire surface may be wrapped with a transparent sheet including a transparent electrode. Also, like this,
The arrangement of the composite electronic devices does not necessarily have to be performed on a plane, and the composite electronic devices can be arranged on a curved surface having an arbitrary curvature as long as each composite electronic device unit can fit.

Since a guest-host system in which a black dichroic dye is blended with a nematic liquid crystal having a negative dielectric anisotropy is used, when no electric field is applied to the liquid crystal layer 60, the long axis of the liquid crystal molecules is Are oriented perpendicular to the substrate, so that the incident light is reflected by the display electrode 52 as it is. By applying an electric field to the liquid crystal layer 60, the major axis direction of the liquid crystal molecules is oriented horizontally with respect to the substrate, and the incident light is absorbed.
This operation is used as an optical shutter, which is combined with an RGB color filter to realize color display by additive color mixing.

The transparent electrode 58 and the upper electrode 52 are maintained at the same potential through the contact electrode 54, and the liquid crystal molecules are vertically aligned. Therefore, light that has entered the liquid crystal layer 60 on the photodiode always enters the photodiode.

It is needless to say that a linear shutter can be made incident by using a polarizing plate and a twisted nematic liquid crystal, converted into circularly polarized light and reflected, and the retardation of the liquid crystal layer can be adjusted to form an optical shutter.

By using the photodiode in the avalanche mode, the light receiving sensitivity can be increased. It is desirable to set the multiplication factor to about 100 times. Visible light from the outside is, for example, Ge or C
Cut off with an infrared filter such as a glass filter using dS-Se-Te colloid. Further, since a Fabry-Perot interference filter having a transmission wavelength at the wavelength used for the optical signal is provided to increase the S / N ratio, the optical signal can be transmitted even if a liquid crystal layer is formed on the surface.

It is needless to say that the optical signal receiving portion may be formed on the substrate surface opposite to the display device of the composite electronic device. In this case, the back surface of the display is shielded from light and the light is If the signal light emitting unit is arranged, no infrared filter or Fabry-Perot interference filter is required.

The reception sensitivity at the shot noise limit corresponding to the code error rate of 10 ^-9 is about 20 in terms of the number of photons. The output of each light pulse is desirably about 200 in photons in each light receiving device.

It is also possible to transmit an optical signal by a plurality of photodiodes using light pulses of a plurality of wavelengths by matching with a Fabry-Perot = interference filter formed on the photodiode. The diffusion of light
It is possible to combine the diffusion plate with an optical lens as appropriate.

Next, referring to the process sectional views of FIGS.
Of the composite display device will be described. In addition, a manufacturing process of one display unit included in the composite display device will be described.

First, as shown in FIG. 4A, an element isolation insulating film 31 is formed on the surface of a p-type silicon substrate 30 by using the STI technique. Then, a p-type impurity is ion-implanted into the region 61 where the photodiode serving as the light receiving element is formed, and the impurity concentration is adjusted. In addition, the formation of a photoresist mask using lithography technology, the ion implantation of n-type impurities, and the diffusion process are sequentially performed to form an LSI for a display control unit.
The n-type well 32 is formed in a part of the region 62 where is formed. Also, a p-type impurity is ion-implanted into the region 63 where the charge holding capacitor is formed, if necessary, to adjust the impurity concentration.

Next, as shown in FIG. 4B, a gate insulating film 33 is formed on the exposed surface of the substrate 30 by a known method such as thermal oxidation or a CVD method. CV all over
A polysilicon film is deposited using the D method or the like. And
After selectively implanting an n-type impurity and a p-type impurity, respectively, patterning is performed to form an n-type gate electrode 34 and a p-type gate electrode 36.

Next, an n-type impurity is ion-implanted into the element region including the n-type gate electrode 34 to form an n-type diffusion layer 35, and the n-type MOSFETs 38, 39, 40, 42, the photodiode 62, and the capacitor 64 To form Then, a p-type impurity is ion-implanted into the element region including the p-type gate electrode 36 to form a p-type diffusion layer 37, and a p-type MO is formed.
The SFET 41 is formed.

Next, as shown in FIG.
A first interlayer insulating film 43 is formed by depositing a silicon oxide film using a method or the like. Then, contact holes connected to the n-type diffusion layers 35c to 35g and the p-type diffusion layers 37a and 37b are respectively formed. Note that the surface of the first interlayer insulating film may be planarized by performing chemical mechanical polishing before forming the contact hole. Then, after a wiring material is deposited by using a sputtering method or the like so as to fill the contact holes, patterning is performed to form plug electrodes 44, lower reflectors 45, contact electrodes 46 and 48, and wirings 47.

After the electrode material is deposited on the entire surface, chemical mechanical polishing is performed to form the plug electrode 44 in the contact hole.
After the formation, the lower reflector 45, the contact electrodes 46 and 48, and the wiring 47 may be formed by depositing and patterning an electrode material. In this case, the surface is further flattened.

The thickness of the lower reflecting plate 45 is appropriately controlled so that it has a high reflectance and does not completely block light. In some cases, a high dielectric constant film such as TiO ₂ may be used. Needless to say, the above steps can be repeated as necessary to form a multilayer wiring layer.

Next, as shown in FIG.
By depositing a silicon oxide film using a method or the like, a second interlayer insulating film 49 is formed. Then, the surface of the second interlayer insulating film 49 is planarized by using a CMP method or the like. The thickness of the second interlayer insulating film 49 is set such that the reciprocating optical path length is an integral multiple of this wavelength so that light of a wavelength of an optical signal from the light emitting device to be detected by the photodiode, for example, 0.85 μm is transmitted. It forms so that it may become.

Then, a contact hole connected to the lower reflector 45 and the contact electrode 48, and a contact hole (not shown) for supplying a power supply voltage to the n-type MOSFET for driving the photodiode and the display control LSI.
Are formed, and through the same process as the formation of the lower reflector 45 and the contact electrode 48, the Fabry-Perot = upper reflector 51 of the interference filter also serving as the power supply electrode,
A display electrode 52 also serving as a reflector of the liquid crystal display device is formed. Note that prior to the formation of the display electrode 52, it is also possible to form irregularities on the surface of the planarized second interlayer insulating film 49 by using the RIE method or the like.

Next, as shown in FIG.
(Spin On Glass, silicon compound RnSi (OH) _4-n and additive), a material containing a fluid silicon oxide material is spin-coated using, for example, a spinner, and then, for example, in a nitrogen atmosphere. By heat treatment at 300 ° C. for 30 minutes, components other than the silicon oxide material are volatilized to form an insulating film corresponding to the thickness of the liquid crystal to be formed, for example, 10 μm.

A contact hole to be connected to the upper reflector 51 is formed in the insulating film by an effective method among known techniques such as a wet etching method. Then, after depositing a metallic substance by using a sputtering method or the like, patterning is performed to form a plug electrode 54, a contact electrode 55, and a dummy electrode 56 connected to the upper reflector 51. Then, the insulating film is continuously removed by an effective method among known techniques such as a wet etching method, and the spacer insulating film 53 is removed.
To form The remaining spacer insulating film 53 also functions as a spacer when the liquid crystal is sealed.

The upper reflector 51 and the display electrode 52
A solution of, for example, a chromium verfluorononanoate complex is applied thereon and dried by heating to form a liquid crystal alignment layer 57 for aligning liquid crystal molecules. In this case, the liquid crystal alignment layer 57 is formed so that the liquid crystal molecules are vertically aligned.
The alignment of the liquid crystal may be performed by dissolving an alignment material in the liquid crystal.

Thereafter, a thermosetting epoxy-based adhesive is provided on the outer periphery, and a plastic plate 59 covered with a transparent electrode 58 such as indium oxide or tin oxide is placed and sealed on the contact electrode 55 and the dummy electrode 56. To wear. The transparent electrode 58 and a part of the plastic plate 59 have holes for liquid crystal injection.

Then, a guest-host type liquid crystal in which a black dichroic dye is added to a nematic liquid crystal having a negative dielectric anisotropy is dropped from an injection port under a reduced pressure atmosphere to form a liquid crystal layer 60. The display unit shown in FIG. 3 is formed by sealing the inlet.

Thereafter, if necessary, the composite display device of the substrate on which a plurality of display units are formed is divided by a technique such as dicing or the like, and a color filter for color display is formed on each liquid crystal pixel. An infrared filter that blocks light and transmits only infrared light, for example, a glass filter using a CdS-Se-Te colloid, is installed on the light-receiving photodiode, and these liquid crystal display unit, display control LSI, and optical signal reception are provided. A composite display device including at least one photodiode on the same substrate is formed.

Next, driving of the display will be described. First, an optical signal detection unit including a photodiode for receiving the optical pulse signal 19 will be described with reference to FIG.
The photodiode 38 includes a photodiode access MOSFET 38 and a reset MOSFET 39.
The power supply electrode 71 is connected via the.

When the access MOSFET 38 and the reset MOSFET 39 are turned on, the photodiode 6
2 is kept the same as the power supply voltage. Thereafter, when the access MOSFET 38 is turned off and a light pulse arrives, electrons are accumulated in the photodiode 62.

Thereafter, the access MOSFET 38 is set to O
When N, the accumulated electrons are stored in the access MOSFET 3
8 to lower the voltage.
This change is read out through a source follower constituted by MOSFETs 82 and 83 at the subsequent stage, and compared with a reference voltage _{Vref by} a comparison identification circuit 74 to detect the arrival of an optical pulse. Since the optical signal is digitally encoded, it suffices if the presence / absence of an optical pulse can be determined.

Next, a process from receiving an optical signal to obtaining an image output will be described with reference to a circuit block diagram in FIG. The optical pulse signal 19 transmitted through the infrared filter is detected by the optical signal detection unit 16 including a photodiode and an amplifier, and if necessary, is output as a digital signal to a subsequent circuit through an equalizer and a discriminator.

A clock counter 83 is provided to control the timing of the operation of these circuits.
A reset or read time designation pulse is output to the optical signal detector 16. In order to synchronize the transmitted optical pulse signal with the clock counter 73, there is a synchronization circuit 74 including a delay circuit or a voltage controlled oscillator (Voltage controlled oscillator). The readout time designation pulse is set to the optical pulse signal 1
Synchronize with the timing of 9. Note that it is convenient if the transmitted optical pulse signal 19 includes a specific arrangement for performing synchronization prior to transmission of image information.

From the clock counter 83 synchronized with the optical pulse signal 19, the digital signal transmitted from the optical signal detector 16, that is, the gate circuit 85 for detecting a sequence header based on a specific rule from the bit stream. A timing pulse is provided.

The bit stream supplied from the optical signal detector 16 is stored in a temporary buffer memory 86, and it is determined whether or not the bit stream includes a sequence header based on the rules.
Is compared with the contents of the header information memory 87 in which the sequence header information is stored. If the sequence headers match, the decision unit 89 outputs a pulse instructing the subsequent bit stream processing. At the same time, information of an upper layer such as an image processing protocol included in the sequence header can be transmitted to the control information processing circuit 90.

In response to the pulse output from the decision unit 89, the gate circuit 91 is opened, and the contents of the bit stream including address information based on a specific rule are stored in the buffer memory 92. This content is searched and compared with the content of an address information memory 93 storing information including its own address using a comparator 94. If the address information matches, the determiner 95 outputs a pulse instructing the subsequent bit stream processing. At the same time, information of the middle hierarchy such as the image processing protocol included in the address information sequence can be transmitted to the control information processing circuit 90.

Each display unit may have not only its own address but also an address indicating a group of display units having several layers. Accordingly, in order to update the image information, a command can be arbitrarily issued to each of the display units, and collective processing can be performed for a specific group of composite electronic devices.

In response to the pulse output from the decision unit 95, the gate circuit 96 is opened, and the contents of the bit stream including control information and image information based on a specific rule are stored in the buffer memory 97.

In response to this content, the control information processing circuit 90
Performs the control specified by. For example, the address information can be updated based on a signal to which the own address information is sent. In this way, the address of each display unit can be freely changed by configuring the display and then scanning using a laser beam or the like whose light source is narrowed down. After removing the defective composite display device and replacing it with a new composite display device, a corresponding address can be given to this. If there is a further layer in the image information, it is processed based on a specific rule. After these processes, a signal for display control is sent to the prediction signal decoding circuit 98.

Then, the prediction signal decoding circuit 88 performs decoding corresponding to the encoding method in the image information encoding section based on the output from the control information decoding circuit 90. And
Based on the decoded image information, a voltage to be applied to the display electrode of the display unit is determined and applied.

According to this embodiment, a composite display device formed on the same silicon substrate and having a liquid crystal display section, a photodiode light receiving element, and an LSI for pixel control, and a low power consumption It is possible to realize a display which can be provided with electric power, thinness, high definition, a large screen, and flexibility without occupying the projection space and with a simple manufacturing process.

The present invention is not limited to the above embodiment. For example, it goes without saying that a field emission method other than liquid crystal can be used as a display device. Thus, it should be understood that the invention is not limited to the specific examples described herein.

In addition to the control signal, external information, for example, the ambient illuminance of the external environment is mixed with the optical signal, and the display content, for example, the gradation and the luminance, are independently controlled for each pixel in accordance with the mixed signal. Is also possible. Further, if a control unit is formed so as to detect a signal from an optical pointer or the like and change the display, an image can be additionally displayed directly on the screen using the optical pointer. Furthermore, by detecting the viewer's location information,
Accordingly, the display content of each pixel can be independently changed. Therefore, an image with a three-dimensional effect can be displayed in synchronization with the movement of the viewer.

Further, if an electric wiring is formed locally between the image display devices and a function of estimating its own display content from information on the display content of the peripheral composite electronic device unit is given to the control device, Even if the update information of all the pixels is not necessarily transmitted, it is possible to autonomously compose the image including the pixels for which the display command is not given, while performing the complement or the like. In addition, the present invention can be variously modified and implemented without departing from the gist thereof.

[0094]

As described above, according to the present invention, the image information is transmitted as the optical signal and transmitted, and the light receiving section for receiving the transmitted signal and the control section for controlling the display section for displaying the image are used. By arranging a plurality of display units in a matrix, it is easy to suppress power consumption, reduce the thickness, increase the definition, and increase the screen size, and the installation location is not limited.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a schematic configuration of a composite display device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a schematic configuration in a case where a display is formed by arranging a composite display device in a matrix.

FIG. 3 is a cross-sectional view illustrating a configuration of a display unit.

FIG. 4 is a process cross-sectional view showing a manufacturing process of the display unit in FIG. 3;

FIG. 5 is a process cross-sectional view showing a manufacturing process of the display unit in FIG. 3;

FIG. 6 is a process cross-sectional view illustrating a manufacturing process of the display unit in FIG. 3;

FIG. 7 is a block diagram illustrating a schematic configuration of an optical signal receiving unit of the display unit.

FIG. 8 is a block diagram showing a schematic configuration of a control unit of the display unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Image information 12 ... Image information coding part 13 ... Optical signal light emitting part 14 ... Composite display device 15 ... Display unit 16 ... Optical signal light receiving part 17 ... Control part 18 ... Display part 19 ... Light pulse signal 20 ... Display 30 ... P-type silicon substrate 31 Element isolation insulating film 32 N-type well 33 Gate insulating film 34 N-type gate electrode 35 N-type diffusion layer 36 P-type gate electrode 37 P-type diffusion layer 38 Photodiode access n-type MOSFET 39 n-type MOSFET for photodiode reset 40 n-type MOSFET 41 p-type MOSFET 42 n-type MOSFET for display electrode access 43 first interlayer insulating film 44 plug electrode 45 lower reflector 46 Contact electrode 47 ... Wiring 48 ... Contact electrode 49 ... Second interlayer insulating film 50 ... Plug electrode 51 ... On Partial reflector 52 Display electrode 53 Spacer insulating film 54 Plug electrode 55 Contact electrode 56 Dummy electrode 57 Liquid crystal alignment layer 58 Transparent electrode 59 Plastic substrate 60 Liquid crystal layer 62 Photodiode 64 Capacitor

Continued on the front page F term (reference) 5C080 AA10 BB06 CC06 CC07 DD07 DD24 DD28 EE29 FF12 FF13 GG09 GG11 JJ02 JJ03 JJ06 5C094 AA05 AA14 AA22 AA43 BA44 BA47 CA19 CA20 CA23 CA30 EA04 EA05 GA01

Claims (5)

[Claims] An optical signal emitting unit for transmitting an optical signal corresponding to image information; an optical signal receiving unit for receiving the optical signal; a control unit for demodulating / decoding the image information from the received optical signal; A display unit that includes a display unit that displays an image corresponding to the image information, wherein a plurality of the display units are arranged in a matrix. 2. The image display device according to claim 1, wherein said optical signal light emitting section transmits an optical signal in which said image information is digitized. 3. The display unit according to claim 1, wherein each display unit is provided with unique address information.
An image display device according to claim 1. 4. The image display according to claim 1, wherein a light receiving surface of the light signal receiving unit for receiving the optical signal is oriented in the same direction as a surface of the display unit for displaying an image. apparatus. 5. The optical signal emitting unit according to claim 1, wherein the optical signal emitting unit transmits an optical signal including at least the address information given to the display unit and image information corresponding to the display unit. 4. The image display device according to 3.