JPH09185332A - Display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the display device which has a large opening ratio and excellent driving characteristics and is easily increased in screen size and definition and low in manufacturing cost. SOLUTION: A liquid crystal display element 13 to which a photoconductive layer 29 generating electric charges in the light emission area of signal line to a driving electrode is joined is arranged in front of an address optical element 12 which is provided with a group of row electrodes 16 on one surface of a light emission layer 19 emitting light in a specific wavelength region and a group of column electrodes 20 on the other surface and emits the signal light at a specific address by scanning those electrodes. While the signal light is made incident on the photoconductive layer 29, liquid crystal 25 is driven. Consequently, the electrodes of the address optical element 12 and the electrodes of the liquid crystal display element 13 are simplified in structure and the display device which has the high opening ratio and high performance and is low in manufacturing cost can be provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an address light element and a display device including the same.

[0002]

2. Description of the Related Art In recent years, as a flat display replacing an CRT, an active matrix type liquid crystal display (AM-L) using thin film transistors (TFTs) is used.
CD) is superior to CRT in terms of display quality, and expectations are high. This AM-LCD has a thin film transistor, which is a three-terminal element, provided for each pixel.
As is well known, a huge number of steps such as a film forming process, a photolithography process, and an etching process are performed on a glass substrate or the like to form a gate electrode, an auxiliary capacitor, a gate insulating film, a semiconductor layer, a source / drain electrode, a pixel electrode, and the like. It has been manufactured through. In addition, MIM as a switching element
An active matrix liquid crystal display in which a (metal insulator metal) element is provided for each pixel has also been realized.

[0003]

However, in the liquid crystal display using the thin film transistor as a switching element, as described above, there is a problem in that the number of manufacturing steps is increased due to the complexity of the structure, and thus the cost is increased. In particular, as the number of pixels increases, the yield significantly deteriorates, and therefore, when manufacturing a large-area display, an increase in cost is a big problem.
In addition, the aperture ratio was as low as about 60 to 80% due to the provision of the thin film transistor for each pixel electrode and the formation of the auxiliary capacitance on the pixel electrode. Further, in the TFT substrate, the film forming temperature of various material films is 250.
Since the temperature is higher than 0 ° C., there is a problem that an LCD cannot be manufactured using a film substrate.

In addition, the LCD using the MIM element has an advantage that the manufacturing cost is lower than that of the TFT, but the yield is deteriorated as the area is increased, so that there is a problem that the cost is also increased. Further, even in the LCD using the MIM element, since the MIM element is provided for each pixel electrode, the aperture ratio is as low as about 80 to 85%, and it is necessary to improve the aperture ratio.

The problem to be solved by the present invention is that the manufacturing cost is low, the aperture ratio is high, the driving characteristics are good, and it is easy to achieve a large screen and high definition, and further low voltage driving and low power consumption. What kind of means should be taken to obtain a display device that simultaneously realizes the conversion? Further, another problem to be solved by the present invention is to make a display device a film substrate to reduce the thickness and weight, and what means should be taken to obtain a flexible display device. There is a point.

[0006]

According to the first aspect of the present invention,
A light-emitting element in which light-emitting regions for generating signal light in a predetermined wavelength region are formed in a matrix by applying a predetermined voltage, respectively, and a photoconductive layer in which regions receiving the signal light from the light-emitting device generate electric charges. And a display element that is driven and displayed in correspondence with the region of the photoconductive layer in which electric charges are generated.

According to the first aspect of the invention, the light emitting regions formed in a matrix form a signal light in a predetermined wavelength range by applying a predetermined voltage, and the signal light is applied to the photoconductive layer of the display element. Incident. Electric charges are generated in the region of the photoconductive layer that receives the signal light. The display element is driven and displayed in correspondence with the region of the photoconductive layer where the charge is generated.

According to a second aspect of the invention, the light emitting element is
A light emitting layer that generates signal light in the predetermined wavelength range; a plurality of first electrodes that are transparent to the signal light and that are arranged side by side in a first direction on one surface of the light emitting layer; A plurality of second electrodes arranged on the other surface of the light emitting layer in a second direction different from the first direction so as to intersect with the first electrode via the light emitting layer in a matrix pattern; It is characterized by having.

According to another aspect of the present invention, there is provided an electrode group in which the first electrode and the second electrode formed on both sides of the light emitting layer via the light emitting layer intersect with the electrode on the other surface side via the light emitting layer. Therefore, by selecting an electrode from each of the electrode groups on both sides and applying a predetermined voltage, the signal light is emitted from an arbitrary light emitting region among the light emitting regions formed in a matrix in the light emitting layer. You can Further, since the first electrode and the second electrode on both sides of the light emitting layer are arranged side by side in a predetermined direction, the forming process thereof becomes easy. Furthermore, by using an electrode that is transparent to the signal light, it becomes possible to irradiate the signal light to the display element side.

According to a third aspect of the present invention, in the light emitting element, one of the first electrode and the second electrode is an anode electrode and the other is a cathode electrode, and the one between the anode electrode and the cathode electrode. In addition, the electroluminescent device is characterized by having a light emitting layer that emits signal light when a voltage is applied. The invention according to claim 4 is characterized in that the light emitting layer of the light emitting element is made of an organic compound. Further, in the invention according to claim 5, the light emitting layer of the light emitting device comprises polyvinylcarbazole and 2,5
It is characterized by comprising a first organic film made of -bis (1-naphthyl) -oxadiazole and a second organic film made of tris (8-quinolylate) aluminum complex.

In the inventions according to claims 3 to 5, since the light emitting layer is an electroluminescent layer which emits light when a voltage is applied, it has a structure in which the first electrode and the second electrode sandwich the light emitting layer. Is easy to manufacture and has an emission wavelength range peculiar to the material of the electroluminescent layer. Particularly, in the invention described in claim 5, polyvinylcarbazole (PVC
z) and a 1,5-bis (1-naphthyl) -oxadiazole (BND) first organic film, and a second tris (8-quinolylate) aluminum complex (Alq3).
Since it is composed of an organic film, Alq3 forming the second organic film functions as an electron transporting material, and BND forming the first organic film functions as an electron transporting material. Also,
PVCz forming the first organic film functions as a hole transporting material. Further, B, which is an electron transporting material in the first organic film,
ND has a lower electron injection energy barrier from the second organic film than the hole transport material, and the hole transport material has a lower hole injection energy barrier from the anode electrode than the electron transport material BND. Become. For this reason, at the interface between the first organic film and the second organic film, recombination of electrons and holes occurs, whereupon an electroluminescence (EL) phenomenon occurs and a predetermined wavelength range (ultraviolet light wavelength (Area) emits light. Further, as described above, since the electron injection energy barrier and the hole injection energy barrier are small, low power light emission is possible. Furthermore, in the inventions of claims 2 and 3, since the organic compound is used as the light emitting layer, it is possible to realize a light emitting element which is lightweight, thin, and flexible.

According to a sixth aspect of the present invention, the signal light in the predetermined wavelength range of the light emitting element is in the wavelength range between 350 nm and 400 nm. In the present invention, since the signal light is in the ultraviolet light wavelength range between 350 nm and 400 nm, it is possible to prevent the drive display from being performed by the light used for the display of the display element in the visible light wavelength range. it can.

The invention according to claim 7 is characterized in that the anode electrode and the cathode electrode of the light emitting element are transparent to the signal light and visible light.
In the present invention, since the anode electrode and the cathode electrode are transparent to the signal light emitted from the light emitting element and the visible light as the display light, the signal light can reach the photoconductive layer and the display can be achieved. Visible light can reach the device.

The invention according to claim 8 is characterized in that the cathode electrode is made of n-type silicon carbide or n-type amorphous silicon. In the present invention, the cathode electrode can be made transparent to the signal light and the visible light by configuring the cathode electrode with these materials.

According to a ninth aspect of the present invention, the display element comprises:
It is characterized in that the liquid crystal and the photoconductive layer are interposed between the front drive electrode and the rear drive electrode, each of which is transparent to visible light and which are arranged to face each other. In the present invention, the liquid crystal can be driven by receiving the signal light through the electrode whose photoconductive layer is transparent. Further, since display light can be transmitted through the electrodes, it is possible to perform display according to liquid crystal driving.

According to a tenth aspect of the present invention, at least one of the front drive electrode and the rear drive electrode is a single electrode formed over the entire display area. In the present invention, since the drive electrode is a single electrode over the entire display area, the patterning step is not required and the manufacturing can be facilitated.

According to an eleventh aspect of the present invention, one of the front drive electrode and the rear drive electrode is transparent to the signal light from the light emitting element and is bonded to the photoconductive layer. It is characterized by that. In the present invention, the signal light from the light emitting element can enter the photoconductive layer through the electrode having transparency, and an electric field can be applied to the liquid crystal between the photoconductive layer and one of the electrodes.

The twelfth aspect of the invention is characterized in that charges having a polarity opposite to that of the front drive electrode are accumulated in the photoconductive layer. In the present invention, the portion of the photoconductive layer where the signal light is incident and the charge is generated, the front drive electrode,
An electric field for driving the liquid crystal can be applied during the period.

According to a thirteenth aspect of the present invention, in the display element, at least one of the display element is transparent to the signal light from the light emitting element, and at least the other is transparent to visible light. It is characterized in that it is an electroluminescent device having an electrode and having a light emitting layer which emits visible light between 401 nm and 800 nm when a voltage is applied between the anode electrode and the cathode electrode. In this invention, when the signal light incident from one side of the anode electrode and the cathode electrode reaches the photoconductive layer and the light emitting layer of the display element emits visible light, the other electrode is transparent to visible light. Since it has it, it can be displayed.

According to a fourteenth aspect of the present invention, the light emitting layer of the display element is made of an organic compound.
According to a fifteenth aspect of the present invention, the light emitting layer of the display element comprises polyvinylcarbazole and 2,5-bis (1-naphthyl)-
It is characterized by comprising a first organic film made of oxadiazole and a light emitting material which emits visible light between 401 nm and 800 nm, and a second organic film made of a tris (8-quinolylate) aluminum complex. In these inventions, since the light emitting layer of the display element is made of an organic compound, the display element can be thin, lightweight and flexible. In particular, since the light emitting element is an organic electroluminescent element, it can have an extremely thin structure and can maintain the spatial frequency to generate charges in the photoconductive layer provided in the display element. Furthermore, since the light emitting layer is formed of an organic compound, it is possible to obtain a light emitting layer having good transparency to visible light. Therefore, by applying the organic compound also to the light emitting layer of the light emitting element corresponding to this display element, a thin, lightweight, and flexible display device can be realized. Further, in the invention according to claim 15, since the electroluminescent element made of these materials is formed, it is possible to realize a display device having low power consumption and excellent portability.

According to a sixteenth aspect of the present invention, the cathode electrode of the display element is made of n-type silicon carbide or n-type amorphous silicon which is transparent to the signal light and visible light. In the present invention, since the cathode electrode is transparent to the signal light and the visible light, it is possible to allow the signal light to enter the photoconductive layer and to emit the display light from the display element.

The seventeenth aspect of the invention is characterized in that the photoconductive layer is formed over the entire display region. In the present invention, since the photoconductive layer is formed of one layer, the display element can be easily manufactured.

The invention according to claim 18 is characterized in that the photoconductive layer is made of zinc oxide (ZnO). In the present invention, since the photoconductive layer made of zinc oxide generates charges by ultraviolet light, the signal light emitted from the light emitting element can be set to ultraviolet light. This can prevent charges from being generated in the photoconductive layer due to incidence of visible light, which is light for display.

The invention according to claim 19 is characterized in that a backlight for irradiating the display element with light is provided behind the display element. The invention according to claim 20 is characterized in that the backlight irradiates the photoconductive layer with light in a wavelength range in which electric charges are not generated. Claim 2
In the invention described in 1, the backlight is 401 nm to 8 nm.
It is characterized by irradiating visible light in the wavelength range between 00 nm. In these inventions, since the light of the backlight is light in a wavelength range that does not generate charges in the photoconductive layer, it is possible to prevent malfunction of the display element.

According to a twenty-second aspect of the present invention, the display element includes a color filter. In the present invention, color display is possible by passing light from the display element through the color filter.

According to a twenty-third aspect of the present invention, there is provided an organic electroluminescent layer for generating signal light composed of light in a predetermined wavelength range excluding the wavelength range of visible light, and an organic electroluminescent layer having transparency to the signal light and visible light. A plurality of first electrodes arranged side by side in a first direction on the front surface of the light emitting layer, and a second surface different from the first direction on the back surface of the light emitting layer, the first electrode being transparent to visible light. A light emitting element having a plurality of second electrodes arranged side by side so as to intersect with the first electrode via a light emitting layer in a matrix form; Between one front drive electrode formed over the entire area and one rear drive electrode formed over the entire display area and transparent to visible light and the signal light. And a photoconductive layer that generates charges only in a predetermined wavelength range of the signal light from the light emitting element and the photoconductive layer. Liquid crystal displayed corresponding to the region where the electric charge is generated, and a liquid crystal display element located on the front surface of the light emitting element and a rear surface of the light emitting element, and visible light is emitted on the light emitting element. And a backlight for irradiating the liquid crystal display element through the backlight.

According to the twenty-third aspect of the invention, since the light emitting layer of the light emitting element is an organic electroluminescent layer, it can be made extremely thin, and the photoconductive layer provided in the liquid crystal display element while maintaining the spatial frequency can be formed. Can generate electric charge, first
Even if high time-division driving is performed on the electrodes and the second electrode, electric charges are formed in the layer thickness direction of the photoconductive layer and are substantially insulated in the plane direction. Virtually simple matrix driving can be performed without making it inside. In addition, since the light emitting element is an organic electroluminescent element, it is extremely thin and can give generally good transparency to visible light. Even if the liquid crystal display element, the light emitting element and the backlight are arranged in this order, the liquid crystal display element is provided. The liquid crystal display element is addressed by the signal light emitted from the light emitting element, and gradation display can be performed according to the light amount of the signal light.
The visible light of the backlight can be applied to the liquid crystal display element without blocking the address to the photoconductive layer by the signal light.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, details of an address optical element according to the present invention and a display device having the same will be described based on embodiments shown in the drawings.

(Embodiment 1) FIG. 1 is a perspective view conceptually showing a part of a display device according to the present invention, and FIG. 2 is a sectional view schematically showing a sectional structure of the display device. In this embodiment, the present invention is applied to a transmissive liquid crystal display element. In the figure, 11 is a display device, and this display device 11
Is generally composed of an address light element 12 as a light emitting element, a liquid crystal display element 13, and a backlight system 14.

The address optical element 12 is, as shown in FIG. 2, an address substrate 1 made of glass or polymer film.
A plurality of row electrodes 16 as an electrode group are formed on the upper surface of the electrode 5 in parallel with each other in the row direction. This row electrode 1
6 has a film thickness of about 250Å to 1000Å and functions as an anode electrode, and at least the light emitting layer 1 described later.
Part of the wavelength range of the ultraviolet light (350 nm to 400 nm) generated by the recombination of electrons and holes within 9 and the visible light wavelength range of the backlight system 14 (401 nm to 800 n).
m) is transparent to, for example, IT
It is composed of at least one of O (indium tin oxide), tin oxide (SnO2), magnesium oxide (MgO) and the like. The upper surface of the plurality of row electrodes 16 and the address substrate 15 is a single layer composed of polyvinylcarbazole (hereinafter referred to as PVCz) and 2,5-bis (1-naphthyl) -oxadiazole (hereinafter referred to as BND). The first organic film 17 having a hole transporting property is formed with a film thickness of about 1000Å. Then, on the first organic film 17, a tris (8-quinolylate) aluminum complex (hereinafter referred to as Alq
The second organic film 18 having an electron transporting property such as
The light emitting layer 19 is formed to have a film thickness of about 500Å.
It is composed of the first organic film 17 and the second organic film 18. The structural formulas of Alq3, PVCz, and BND are shown below.

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On the upper surface of the second organic film 18, as shown in FIGS. 1 and 2, a plurality of column electrodes 20 parallel to the column direction intersecting (orthogonal to) the row electrodes 16 with the light emitting layer 19 interposed therebetween. Are formed. The column electrode 20 functions as a cathode electrode and has a physical property of having a lower work function than the anode electrode. For example, MgIn, AlLi, MgIn.
-A metal electrode such as Al, or n-type amorphous silicon (a-) that has transparency to visible and ultraviolet light wavelength regions.
Si), n-type silicon carbide and the like.

Then, the protective film 2 having a light-transmitting property is formed so as to cover the column electrodes 20 except the light emitting layer 19 and the terminal portion 20A.
1 is formed. Although not shown, the terminal portion of the row electrode 16 is also exposed without being covered with the protective film 21. As the protective film 21, it is possible to use, for example, a silicon nitride film or a silicon oxide film, which is transparent to light in the visible light wavelength range and the ultraviolet light wavelength range. The protective film 21 prevents oxidation of the column electrodes 20 and prevents characteristic deterioration due to moisture, but it is not always necessary depending on the physical properties of each member of the address optical element 12.

The address optical element 12 thus constructed
In the above, when the electric field is applied between the row electrode 16 and the column electrode 20, the second organic film 1 in the first organic film 17 is
From the portion near the interface with 8 the ultraviolet light (35
Light in a predetermined wavelength range of 0 to 400 nm) is emitted. In addition, it is preferable that the wavelength range of the signal light and the wavelength range of the visible light as the irradiation light of the backlight system 14 are separated as much as possible, and the ultraviolet light in the wavelength range of 350 to 400 nm is output as the signal light. It is desirable to set to. The row electrodes 16 and the column electrodes 20 extend to the edge of the address substrate 15, the terminal portions are exposed from the protective film 21, and are connected to a driving IC (not shown). In this way, the matrix-driven address optical element 12 is constructed. When a member that is easily oxidized from the work function value is used as the column electrode 20, the exposed surface of the terminal portion may be plated with a member that is not easily oxidized.

The liquid crystal display element 13 to be combined with the address light element 12 having such a structure is the address light element 12
The display area has an area similar to that of the light emitting area. The configuration of the liquid crystal display element 13 will be described below with reference to FIG.

The liquid crystal display element 13 includes a pair of front transparent substrate 22 and rear transparent substrate 23, twist nematic liquid crystal 25 sealed by a sealing material 24 between these transparent substrates, and these transparent substrates 22, 23 has a linear polarization axis disposed on the outer surface side of 23, includes a pair of front polarizing plate 26 and rear polarizing plate 27, and is configured to use a TN cell having optical activity. And in this Embodiment 1,
On the inner surface of the rear transparent substrate 23 facing the transparent transparent substrate
The rear drive electrodes 28 are formed over the entire display area. Further, a photoconductive layer 29 is formed on the surface of the rear driving electrode 28.
Are formed. Further, a post-alignment film 30 is formed so as to cover the photoconductive layer 29.

The photoconductive layer 29 is made of a material that absorbs photons in a specific wavelength range to generate conductive carriers. Examples of such a photoconductive layer 29 include ZnO and amorphous silicon (a-Si). Amorphous selenium (a-S
e), ZnS, SrTiO ₃ , GaN, CdS, SnO _x
Inorganic semiconductors such as, charge transfer complexes such as polyvinylcarbazole, organic photocarrier generation layers (perylenes, quinones, phthalocyanines, etc.) and organic carrier transport layers (arylamines, hydrazines, oxazoles, etc.)
A material such as an organic composite material in which and are stacked can be used. In such a material, a photon in a specific wavelength region is absorbed, and a conductive carrier composed of an electron-hole pair is generated,
The impedance of the region where the photons are absorbed sharply decreases, so that the region becomes electrically conductive.
In particular, in the first embodiment, ZnO is used because the photoconductive layer 29 has a light absorption characteristic for signal light (ultraviolet light) and has a sharp peak of spectral sensitivity in the ultraviolet light wavelength range. ZnO
Usually has no absorption in the visible light range. In order to extend the photoelectric effect to the visible light region in ZnO, an organic dye is usually used as a sensitizer. FIG. 3 shows the photovoltage of ZnO (indicated by a circle) and Z using eosin as a sensitizer.
It is the graph showing the photovoltaic spectrum with the photovoltaic power of nO (indicated by triangles). From this graph, ZnO absorbs only in the ultraviolet region and Zn with eosin as a sensitizer is used.
It can be seen that O has absorption in the wavelength range of about 450 to 600 nm.

On the other hand, on the inner surface facing the front transparent substrate 22,
A color filter layer 31 having a predetermined color arrangement is formed over the entire display area. Further, on the surface of the color filter layer 31, one front drive electrode 33 made of ITO is formed on the entire surface with a protective film 32 made of a transparent silicon nitride film interposed therebetween. Further, a pre-alignment film 34 is formed so as to cover the pre-driving electrode 33. In the liquid crystal display element 13 having such a configuration, the front drive electrode 33 and the rear drive electrode 28 do not require a fine patterning step, and it is sufficient to form a film over the entire display region. Throughput can be dramatically improved and manufacturing cost can be significantly reduced as compared with a display element in which a TFT is a switching element. Further, since the drive electrodes 28 and 33 for applying a voltage to the liquid crystal 25 are formed over the entire display surface, the TFT, a drain line connected to the drain electrode of the TFT and supplying a signal voltage, The structure does not require a gate line connected to the gate electrode and supplying a scanning voltage, and further, no storage electrode (auxiliary capacitance electrode). Therefore, the aperture ratio is extremely high, and excellent contrast can be obtained. The liquid crystal display element 13 and the address light element 12 described above have a dot arrangement of the address light element 12 (a portion where the row electrode 16 and the column electrode 20 intersect each other) with respect to the color arrangement of the color filter layer 31. The arrangement is such that the signal light is incident on the photoconductive layer 29 while maintaining the spatial frequency. The stippled part in Figure 1
The dot portion d is shown. Further, as shown in FIG.
A rear polarizing plate 27 of the liquid crystal display element 13 is provided on the lower surface of the address light element 12, and a backlight system 14 is disposed behind it. The backlight system 14 is generally composed of a light source 35 that emits visible light and a light guide plate 36 made of acrylic or the like.

Next, the operation and operation of the first embodiment will be described. First, FIG. 4 shows a schematic energy diagram of the address optical device 12 of this embodiment. This energy diagram explains the effect on the electron and hole injection barrier by mixing BND, which has an electron transporting property rather than PVCz, in PVCz as the first organic film 17 bonded to the row electrode (anode) 16.

In FIG. 4, the alternate long and short dash line shows the energy structure peculiar to BND, and the broken line shows the energy structure peculiar to PVCz. In the case of the composite film in which the respective components are mixed in this way, in terms of the movement of electrons from the second organic film 18 side made of Alq3 to the first organic film 17, the second organic film 18 and the first organic film 18 are formed.
Considering the electron affinity of each interface with the organic film 17, the first organic film 17 reflects the physical properties of the component having a smaller electron potential. That is, this interface reflects the physical properties of BND, which is an electron transporting dopant. On the contrary, in the movement of holes from the row electrode (anode) 16 side to the first organic film 17, at the ionization potential of the first organic film 17 at the interface with the row electrode 16,
It reflects the physical properties of smaller materials with hole potentials. That is, the physical properties of PVCz, which also functions as a binder, are reflected in the interface on the first organic film 17 side. In addition, from the row electrode 16 to the first organic film 17
Since the energy barrier to the is reflected in the energy barrier of PVCz, HfromA is relatively small, and holes can be easily injected into the first organic film 17 by applying a predetermined voltage. It is difficult to inject holes from 17 into the second organic film 18 because the energy barrier HtoAlq3 is large. As a result, the electronic properties of the entire light emitting layer 19 have an energy structure shown by the diagonal lines in the figure when focusing on the injection barrier at the interface. That is, regarding the injection barrier of carriers, mixing BND reduces the energy barrier from the second organic film 18 to the first organic film 17 by the energy barrier EtoBND, and
The injection of electrons into 7 is facilitated. Therefore, light emission is performed near the interface between the first organic film 17 and the second organic film 18. In such an address light element 12, the use of the organic EL layer makes it possible to satisfy the conditions of high-speed response and highly efficient light. In addition, the first organic film 17 is a BND.
Instead of Alq3, a member having an electron potential lower than that of Alq3 may be mixed in PVCz so that light of light energy hv is emitted near the interface with the mixed layer in Alq3.

Next, when the row electrodes 16 and the column electrodes 20 are selected and matrix-driven in the address light element 12, signal light is emitted from the light emitting layer 19 (belonging to a predetermined dot portion d) at a predetermined address. The action and operation of the photoconductive layer 29 in the case of being described will be described with reference to FIGS. 5 and 6.

FIG. 5A shows the structure of the rear drive electrode 28, the photoconductive layer 29, the liquid crystal 25, and the front drive electrode 33.
It shows a state in which the AC drive voltage Vd is applied between 8 and 33. Here, the basic concept will be described by ignoring the voltage drop in the alignment films 30 and 34. In this state, in a state where the address optical element 12 is not driven (a dark state in which signal light in a specific wavelength range is not output), that is, in the initial state, the voltage is divided by the impedance Zpc of the photoconductive layer 29 and the impedance Zdr of the liquid crystal 25. , Voltage V on the photoconductive layer 29
The voltage Vdr is applied to the liquid crystal 25 by pc. FIG.
(B) shows an equivalent circuit in the initial state. C in the figure
dr is the capacitance of the liquid crystal 25, Cpc is the capacitance of the photoconductive layer 29,
Rdr is the resistance of the liquid crystal 25, and Rpc is the resistance of the photoconductive layer 29. The resistance Rpc is a variable resistance that correlates with the amount of photogenerated carriers, and is in a dark state (initial state) as shown in FIG.
Has extremely high resistance. Therefore, in this state, most of the AC drive voltage is applied to the photoconductive layer 29. That is, the internal electric field of the liquid crystal 25 is low, and the alignment of the liquid crystal is in a state corresponding to the alignment films 30 and 34.

Next, as shown in FIG. 6A, when signal light of a specific wavelength region is emitted at a predetermined address of the address optical element 12, the photoconductive layer 29 of the dot portion d corresponding to the same address is emitted. The light is absorbed and excited, and a conductive carrier composed of an electron-hole pair is generated in that portion. That is, the optical pattern of the signal light in the specific wavelength range emitted from the address optical element 12 is converted into the density pattern of the conductive carriers of the photoconductive layer 29. The amount of conductive carriers produced depends on the intensity of incident light, time, and wavelength range.
At this time, the conduction carriers are affected by the driving electric field,
The photoconductive layer 29 is moved / reciprocated in the vertical direction (thickness direction). In the plane direction of the photoconductive layer 29 (parallel to the rear transparent substrate 23), there is no external electric field, so that the conduction carriers do not move in that direction. Therefore, only the dot portion d irradiated with the signal light has a low resistance Rp as shown in FIG.
It becomes c1. Then, the impedance Z of the photoconductive layer 29
The pc decreases, and the partial pressure of the liquid crystal 25 with respect to the impedance Zdr increases. That is, the electric field strength received by the liquid crystal 25 is modulated by reflecting the density pattern of the conductive carriers. Therefore, the liquid crystal 25 is aligned in a predetermined direction and transmits light (visible light) from the backlight system 14 to allow liquid crystal display. At this time, since the photoconductive layer 29 exhibits photoconductivity only in the wavelength range of the signal light (ultraviolet light), it is not affected by the light from the backlight system 14.

FIG. 6B shows the resistance Rpc of the photoconductive layer 29.
However, it shows that the signal light gradually increases from the time when the incidence of the signal light ends. This is because the photo-generated carriers in the photoconductive layer 29 have a specific lifetime (average time) (affected by impurities and lattice defects), and as a result, the electric field intensity pattern of the liquid crystal 25 is photoconductive. The signal light is attenuated according to a certain time constant from the time when the signal light is incident on the layer 29. As a result, the resistance component Rpc of the photoconductive layer 29 increases again, and the electric field strength of the liquid crystal 25 gradually decreases accordingly. It should be noted that the liquid crystal 2 can be set by setting the entire scanning period of a sufficient time for the decay time that is formed by such a time constant.
It is possible to maintain the electric field intensity pattern received by 5 substantially constantly. FIG. 7A shows a change in the effective voltage of the liquid crystal layer with respect to the optical pulse emitted from the address optical element 12 side. In order to keep the electric field intensity pattern practically steady, it can be sufficiently dealt with by setting the entire scanning period within the decay time of the effective voltage of the liquid crystal layer, as shown in FIG. Therefore, this embodiment does not require an auxiliary capacitance electrode as in the conventional liquid crystal display element. In order to drive / emit the address light element 12 to obtain a signal light pattern (optical image), each electrode group of the row electrode 16 and the column electrode 20 may be line-sequentially driven, for example, an average voltage driving method or the like. Various well-known driving methods can be applied. FIG. 8A is an equivalent circuit diagram of a matrix when one of the row electrode 16 and the column electrode 20 is a select line and the other is a data line, and FIG. 8B is one scanning line when line-sequential scanning is performed. 6 is a timing chart showing a selection time and a whole scanning cycle (frame). Further, although AC driving is performed in this embodiment, a pulse train whose polarity is inverted may be used.

Next, a method of driving using a DC power source in this embodiment for convenience will be described below. For convenience of description, the operation with a single dot will be described first, and then the matrix operation will be described.

[Operation with Single Dot] (1) Initial State (FIG. 9B) FIG. 9A shows a rear drive electrode 28, a photoconductive layer 29, and a liquid crystal 2.
5. In the structure of the front drive electrode 33, a state in which the DC drive voltage Vd is applied between the electrodes is shown. FIG. 9B shows an initial state (dark state).
DC voltage Vd is applied between 8 and 33, and the light emitting layer 1
9 is not driven. Therefore, the resistance component Rpc of the photoconductive layer 29 is in a high state. Capacitance component C of liquid crystal 25
dr charges the amount of charge determined by the resistance partial pressure of the resistance component Rdr of the liquid crystal 25 and the resistance component Rpc of the photoconductive layer 29.

(2) Writing Operation (FIG. 10A) The light emitting layer 19 is driven while the DC voltage Vd is applied between the front and rear drive electrodes 28 and 33. Then, the light emitting layer 1
Signal light (address) from 9 is incident in the thickness direction of the photoconductive layer 29, the conductivity of the dot portion on which the signal light is incident increases, and the resistance component Rpc thereof decreases. Therefore, charges are injected into the capacitance component Cdr of the liquid crystal 25 through the resistance component Rpc. Along with this, the electric field inside the liquid crystal 25 increases. This charge injection amount depends on the amount of photogenerated carriers in the photoconductive layer 29. That is, by changing the light emission energy of the signal light or the irradiation time, the liquid crystal 2
It is possible to control the amount of charges injected into the capacitance component Cdr of No. 5. Accordingly, gradation display can be performed.

(3) Charge holding state (FIG. 10 (b) / FIG. 1)
1 (a)) When the driving of the light emitting layer 19 is stopped, the resistance component Rpc of the photoconductive layer 29 returns to a high state with time. Here, the photoconductive layer 29 is required to have a short time constant. As a result, the injected charge is caused by the capacitance Cdr of the liquid crystal 25 and the photoconductive layer 29.
Remains on the interface side with the liquid crystal 25. In this state, FIG.
Even if Vd is reduced to 0 V or a voltage lower than the driving voltage as shown in (a), the state is maintained as in the state of FIG. 10 (b). That is, the electric field inside the liquid crystal 25 is maintained. At this time, charges are redistributed between the capacitors Cdr and Cpc, but since Cpc is sufficiently smaller than Cdr, the fluctuation range is sufficiently small, and most of the charges are Cdr.
Therefore, it is possible to obtain a display having a good holding characteristic.

(4) Erase operation (FIG. 11 (b) / FIG. 12)
(A)) Vd as shown in FIG. 11B is set to 0V or a voltage sufficiently lower than that at the time of writing, and then the light emitting layer 19 is driven with sufficient light output as shown in FIG. 12A. To do. As a result, the resistance component Rpc of the photoconductive layer 29 decreases, so that the charge component at the time of writing is discharged from the capacitance component Cdr of the liquid crystal 25 through the Rpc, and as shown in FIG. The electric field is erased.

[Matrix Operation] FIG. 13 shows the display device 1.
1 shows the drive control method of No. 1 and shows the timing of the drive voltage Vd waveform and the light emission pulse at each pixel address. FIG. 13B shows the timing of the drive voltage Vd applied to the liquid crystal 25 between the electrodes 33 and 28 of the liquid crystal display element 13 and the photoconductive layer 29. The pulse train is synchronized with the “one scanning line selection time” determined by the line-sequential driving method of the electrodes 20. The polarity of the drive voltage Vd is not inverted at least within the scanning time of all the scanning lines. Then, as shown in FIG. 13A, the drive voltage Vd is obtained by dividing one scanning time into at least two (not necessarily equal to each other), the “HI” potential, and the “LOW” potential (in the figure, Zero potential). Hereinafter, the “HI” potential is referred to as a writing time potential, and the “LOW” potential is referred to as an erasing time potential. In addition,
As shown in the figure, it is desirable that the first half of the selected one scanning time is the erasing time and the latter half is the writing time. FIG.
3 (c), (d), and (e) show the light emission pulse of a specific dot portion d in the XY matrix composed of the row electrodes 16 and the column electrodes 20 that are line-sequentially driven.
Note that FIG. 13C shows a light emission pulse of a certain dot portion d on the first select line, FIG. 13D shows a light emission pulse of a certain dot portion d on the second select line, and FIG. Three
The light emission pulse of a certain dot portion d on the select line is shown. Here, one of the row electrode 16 or the column electrode 20 is used as a select line.

These select lines are shown in FIG.
As shown in (e), an optical pulse having a sufficient output for the erase time is output. At this time, since the value of Vd is the “LOW” potential, the electric field accumulated in the liquid crystal 25 during the previous scanning time is erased by the mechanism shown in FIG.

Next, at the writing time, light energy based on desired data is output. In the figure, an example of pulse height modulation is shown, but pulse width modulation may be used. At this time, since the value of Vd is the “HI” potential, the desired electric field corresponding to the write data is applied to the liquid crystal 25 by the mechanism shown in FIG. While the other select lines are being driven, no optical pulse is given to the dot portion d, and only the driving electric field Vd repeats HI / LOW, so that FIG. 10B and FIG.
As shown in (b), the desired electric field is maintained.

Although the matrix driving method of this embodiment has been described above, by using such a method, data writing, holding time, and even erasing can be freely performed. This has substantially the same driving characteristics as a liquid crystal display device using a TFT.

In this embodiment, with the above structure, the light (visible light) emitted from the backlight system 14 to the liquid crystal display element 13 is not absorbed by the photoconductive layer 29, and the photoelectromotive force is reduced. Since it does not occur, the liquid crystal display performance is not impaired. In addition, in this embodiment, a virtually static drive potential can be applied to the liquid crystal layer. Further, structurally, there is no area occupied by the active element, so that the transmittance of display light is significantly improved, and a high aperture ratio can be achieved. Further, the address optical element 1
Since the second row electrodes 16 and the second column electrodes 20 have a simple striped structure, they are extremely easy to process, and only a few lithographic steps are required throughout the display device. When forming the light emitting layer 19, the first organic film 17 and the second organic film 18 only have to be vapor-deposited or applied in order, so that the manufacture of the address optical element 12 becomes very simple. Further, in FIG. 2 schematically showing, the rear drive electrode 28 is shown to be covered with the photoconductive layer 29, but in reality, the rear drive electrode 28, the photoconductive layer 29, the rear alignment film 30 and the like are sequentially arranged. Since the film-formed structure is sufficient, the number of steps of the liquid crystal display element 13 can be greatly reduced as compared with the conventional one, and the structure is simple, so that the yield is extremely high and thus the yield is high. Therefore, it becomes easy to achieve a large screen. Further, since there is no occupied area of active elements in one pixel, there is an advantage that high definition can be supported. Moreover, by using the organic EL material as the light emitting layer as in the first embodiment, it is possible to realize low voltage driving of about 5 to 10 V and low power consumption. Incidentally, this driving voltage is almost the same as that of the liquid crystal display element using the TFT as an active element, which is much smaller than that of the display using plasma, and is a display device excellent in portability. In the first embodiment, since the light emitting layer 19 is used as the signal light generating means and is not used as the display light, relatively weak light emission is sufficient, and the life of the light emitting layer 19 is extended. be able to. Further, in this embodiment, the signal light is 350 n
Although ultraviolet light in the wavelength range between m and 400 nm was used, it falls outside the wavelength range of visible light used for liquid crystal display, for example, 80
It is also possible to use a wavelength range such as infrared light of 1 nm to 1 mm and set the photoconductive layer having a peak of photovoltaic power in this wavelength range. Further, in this embodiment, each substrate is made of a glass substrate, but since the light emitting layer 19 is made of a flexible organic material, the flexible substrates 15, 22, 23 made of resin, for example, are used. By adopting, it becomes possible to make a display device having flexibility. The rear polarization plate 27 linearly polarizes the visible light from the backlight system 14 and emits it, but the signal light of the address light element 12 is polarized by the polarization plate 2.
Since it can reach the photoconductive layer 29 without being polarized by 6 and 27, it is sufficient to emit extremely weak light. further,
The color filter layer 31 applied to this embodiment may have a stripe arrangement or a mosaic arrangement. As described above, by using the organic EL element as the address light element 12, it is possible to reduce the thickness, and the signal light is irradiated only to the region corresponding to the predetermined dot of the photoconductive layer only through the column electrode and the row electrode. be able to.

That is, in the display device 11 of the present embodiment, the photoconductive layer 29 of the liquid crystal display element 13 absorbs the signal light (UV light 350 nm to 400 nm) of the address light element 12 and conducts by electron-hole pairs. Generates carriers and emits light from the backlight system 14 (visible light 401 nm to 8 nm).
(00 nm) has substantially no light absorption property, so that visible light can be sufficiently transmitted. Further, since the address light element 12 is an organic EL element, it has generally good transmittance in the visible light wavelength range. Therefore, conductive carriers can be generated in a predetermined region of the photoconductive layer 29 of the liquid crystal display element 13 in accordance with the signal light emitted by the line-sequential driving of the address light element 12, and the backlight is provided. The light of the system 14 can enter the liquid crystal 25 through the address light element 12 and the photoconductive layer 29 without disturbing the signal light of the address light element 12 to perform display.

The address optical element 12 includes an address substrate 15
With the exception of the above, the structure has a thickness of about 1000 Å to 5000 Å. Therefore, a matrix drive display device having a high-density mounting structure in which the liquid crystal display element 13, the address light element 12, and the backlight system 14 are sequentially stacked can be realized.

Further, the display device 11 of this embodiment does not need to be manufactured by arranging a switching element such as a TFT for active driving in the liquid crystal display element 13 so that it can be manufactured.
Since there is no photolithography process associated with FT manufacturing, and further, it is not necessary to pattern the pixel electrodes of the liquid crystal display element 13 for each pixel dot, and high time division driving can be performed
It is possible to manufacture with high throughput and yield in a small number of steps by applying a simple manufacturing device, and the productivity is particularly good in a display device with a large screen compared to a display device equipped with an active display element of TFT. It is a structure.

In the present embodiment, the column electrode 20 is preferably a light transmissive electrode, but even a visible light non-transmissive electrode is formed in a striped shape, so that the visible light of the backlight system 14 is formed. Can irradiate the liquid crystal display element 13 from between the column electrodes 20.

(Second Embodiment) FIG. 14 is a sectional view schematically showing a display device according to a second embodiment of the present invention. In this embodiment, the post-polarizing plate 2 of Embodiment 1 described above is used.
7 is arranged between the front (front surface) of the address optical element 12 and the rear of the rear transparent substrate 23. Note that the other configurations are substantially the same as those of the above-described first embodiment.
In this embodiment, since the liquid crystal display element 13 and the address light element 12 are completely separate from each other, the polarization axis of the polarizing plate can be adjusted relatively easily only by the liquid crystal display element 13. Further, the end face of the rear transparent substrate 23 of the liquid crystal display device 13 and the end face of the address substrate 15 are aligned with each other, and the intersection of the electrodes 16 and 20 of the address optical device 12 and the color filter layer 31 are set to be aligned. You can also do it. Although the rear polarizing plate 27 is disposed between the address optical element 12 and the photoconductive layer 29, the signal light is set to an amount that does not hinder the arrival at the photoconductive layer 29, or the signal light has a wavelength. It suffices to apply a polarizing plate having a high transmittance in the region.

In this case, since the row electrode 16 of the address light element 12 interposed between the light emitting layer 19 and the photoconductive layer 29 is an anode electrode, it is easy to set it as a transparent electrode such as ITO. Has a low work function and thus has reflectivity for visible light and signal light, the signal light of the light emitting layer 19 directly reaches the photoconductive layer 29, and reflected light of the signal light from the column electrode 20 is generated. Since it reaches the photoconductive layer 29, a higher light intensity can be obtained, and even a relatively weak signal light can be addressed favorably, and further, the visible light of the backlight system 14 can be transmitted through the gap between the column electrodes 20 to the liquid crystal display element 1.
Can be reached.

(Embodiment 3) FIG. 15 is a sectional view schematically showing a display device according to Embodiment 3 of the present invention.
This embodiment has substantially the same configuration as the above-described first embodiment, except that the rear polarizing plate 27 is disposed between the rear transparent substrate 23 and the protective film 21 of the address optical element 12. It is a point. The operation of this embodiment is the same as that of the above-described first embodiment, and thus the description thereof is omitted.

In the display device according to this embodiment, the signal light from the light emitting layer 19 does not pass through the address substrate 15 as in the display device 11 according to the first embodiment.
There is no attenuation due to the absorption of light, and good light transmission efficiency can be obtained. Further, the organic EL element is extremely weak against heat and has a property of remarkably deteriorating the light emitting characteristics of the element. The address substrate 15 is provided between the backlight system 14 and the backlight system 14 that generates heat associated with irradiation.
Since it is interposed, it has a structure that can suppress thermal deterioration. Further, it is possible to suppress thermal deterioration of the rear polarizing plate 27, and it is possible to obtain a good display for a long period of time. Although the rear polarizing plate 27 is disposed between the address optical element 12 and the photoconductive layer 29, the signal light is set to an amount that does not hinder the arrival at the photoconductive layer 29, or the signal light has a wavelength. It suffices to apply a polarizing plate having a high transmittance in the region.

(Fourth Embodiment) FIG. 16 is a sectional view schematically showing a display device according to a fourth embodiment of the present invention.
In this embodiment, the rear polarizing plate 2 is provided on the rear surface of the protective film 21 of the address display element 12 having the same arrangement as that of the second embodiment.
7 is arranged, and other structures are the same as those in the second embodiment.
Is the same as Also in this embodiment, the rear polarizing plate 27
Is located behind the address optical element 12, it is possible to prevent the signal light emitted from the address optical element 12 from being influenced by the rear polarization plate 27. Further, since the signal light does not have to pass through the rear polarizing plate 27, weaker light can be used as the signal light. Further, since the light and heat generated from the backlight system 14 are reduced and transmitted by the rear polarizing plate 27, the deterioration of the light emitting layer 19 can be suppressed, and the signal light can be continuously emitted for a long period of time. Here, since the row electrode 16 of the address light element 12 interposed between the light emitting layer 19 and the photoconductive layer 29 is an anode electrode, it is easy to set it as a transparent electrode such as ITO, and the column electrode 20 temporarily has low work. Even if the signal light of the light emitting layer 19 reaches the photoconductive layer 29 directly even if it has reflectivity for visible light and signal light due to the function, the reflected light of the signal light by the column electrode 20 is a photoconductive layer. Since it reaches 29, the light intensity becomes higher and good addressing can be performed even with relatively weak signal light.
Visible light of the backlight system 14 can reach the liquid crystal display element 13 through the gap between the zeros.

(Fifth Embodiment) FIG. 17 is a sectional view schematically showing a display device according to a fifth embodiment of the present invention.
In this embodiment, the address optical element 12 has a rear address substrate 15A and a front address substrate 15B,
A rear polarizing plate 27 is interposed between the rear transparent substrate 23 of the liquid crystal display element 13 and the front address substrate 15B of the address optical element 12. Other configurations are substantially the same as those in the above-described third embodiment. In this embodiment, since the polarizing plates 26 and 27 are provided on both front and rear surfaces of the liquid crystal display element 13, the polarization state can be inspected by the liquid crystal display element alone. Further, since the address optical element 12 has the front address substrate 15B having a flat front surface, the bondability with the rear transparent substrate 23 is improved. Further, since the light emitting layer 19 is sandwiched between the pair of substrates 15A and 15B, it is possible to prevent the light emitting layer 19 from being broken and peeled off when an excessive bending stress is applied. Although the rear polarizing plate 27 is disposed between the address optical element 12 and the photoconductive layer 29, the signal light is set to an amount that does not hinder the arrival at the photoconductive layer 29, or the signal light has a wavelength. It suffices to apply a polarizing plate having a high transmittance in the region.

In each of Embodiments 1 to 5, multicolor display can be performed by using a color filter, and the modes of the liquid crystal display element include a twisted nematic (TN) liquid crystal mode and Ferroelectric liquid crystal (F
CL) mode, antiferroelectric liquid crystal (AFLC) mode, polymer dispersed liquid crystal (PDLC) mode, phase transition (PC) mode and the like can be applied. In addition, a polarizing plate, a retardation plate, and an alignment film may be set according to these liquid crystal modes. For example, in the PDLC liquid crystal mode, it is not necessary to dispose a polarizing plate, and an alignment film subjected to an alignment treatment is also necessary. Absent.

Further, in the display devices according to the first to fifth embodiments, it is desirable that the distance between the light emitting region of the light emitting layer 19 of the address light element 12 and the photoconductive layer 29 is short from the viewpoint of light diffusivity. Specifically, it is preferable that the protective film 21 and the rear transparent substrate 23 are as thin as possible, and the light emitting region of the light emitting layer 19 is as close as possible to the photoconductive layer 29 of the address light element 12, that is, the light emitting layer 19 is as photoconductive as possible. Layer 2
It is desirable to be on the 9 side. Further, between the light emitting layer 19 and the photoconductive layer 29, it is preferable that the photoconductive layer 29 is composed only of a member that transmits as much light as possible in a wavelength range in which conduction carriers composed of electron-hole pairs are generated. .

(Sixth Embodiment) FIG. 18 is a sectional view schematically showing a display device according to a sixth embodiment of the present invention. In this embodiment, as shown in FIG.
2 includes a row electrode 16, a light emitting layer 19, and a column electrode 20 formed between the rear address substrate 15A and the front address substrate 15B. Further, the liquid crystal 25 has a birefringence control (EC
B) type liquid crystal is used, and the front drive electrode 33 is directly formed on the inner surface of the front transparent substrate 22 of the liquid crystal display element 13 facing the front surface without a color filter. Then, on the surface of the post-alignment film 30, a predetermined direction (0
The orientation treatment such as rubbing is performed on the (direction of 30 °) 30a. Alignment such as rubbing is performed on the surface of the front alignment film 34 in the direction of 34a shown in FIG. 19B (counterclockwise with respect to the orientation direction 30a of the alignment process of the rear alignment film 30 by approximately 90 °). Has been processed.

The liquid crystal 25 is made of a nematic liquid crystal or the like to which a chiral material is added, and is twisted by about 90 ° from the rear transparent substrate 23 to the front transparent substrate 22 in accordance with the alignment treatment with the alignment films 30 and 34. And is oriented. As shown in FIG. 19A, the polarization plate 26a of the front polarizing plate 26 is set to 130 ° with respect to the alignment treatment direction 30a. As shown in FIG. 19C, the polarization plate 27a of the rear polarizing plate 27 is set to 150 ° with respect to the alignment treatment direction 30a. The front polarizing plate 26 may be arranged so that its polarization axis 26a is 20 ° to 70 °, preferably 35 ° to 50 ° to the left or right with respect to the alignment treatment direction 34a, and the rear polarizing plate 27 is Its polarization axis 27
a is 20 ° to the left or right with respect to the alignment treatment direction 30a
It may be arranged at an angle of up to 70 °, preferably 25 ° to 45 °.

The liquid crystal display element 13 set as described above
The address optical element 12 is assembled by bonding the front address substrate 15B and the rear transparent substrate 23. In the display device 11 having such a configuration, the front drive electrode 33,
The liquid crystal 2 between the photoconductive layer 29 which is electrically conductive by light
When a voltage is applied to No. 5, the hue changes due to the birefringence effect of the liquid crystal 25 in a voltage range below a certain voltage value (about 2.4 V). Only the results were changed. Specifically, the applied voltage is 0V to 1V, red, and green near 1.8V, 2.2.
It is blue near V, has the lowest brightness near 2.4 V, and is black, and at a voltage value higher than that, approaches white with high brightness as the applied voltage increases. Therefore, the color display color can be controlled by applying an arbitrary voltage of 2.4 V or less to each pixel. Further, the luminance gradation can be controlled by applying an arbitrary voltage in the range exceeding 2.4 V to each pixel. In this embodiment, the emission intensity of the signal light output from the light emitting layer 19 can be controlled by adjusting the voltage applied between the row electrode 16 and the column electrode 20. Therefore, the impedance of the photoconductive layer 29 is modulated according to the light intensity of the signal light incident on the photoconductive layer 29, and the voltage between the photoconductive layer 29 and the front drive electrode 33 sandwiching the liquid crystal 25 changes. As described above, it is possible to control the hue and the brightness gradation, and it is possible to perform multicolor hot water.

Also in this embodiment, the rear polarizing plate 27 is arranged behind the addressing optical element 12 and in front of the backlight system 14 as in the case of the first embodiment. Since the signal light emitted from the optical element 12 does not have to pass through the rear polarizing plate 27, weaker light can be used as the signal light.
Further, in this embodiment, since the color filter is not provided, there is an advantage that the spectral transmittance is improved. Furthermore, since the address optical element 12 has the rear address substrate 15A and the front address substrate 15B, there is an advantage that the address optical element 12 can be easily handled and can be easily assembled with the liquid crystal display element 13 side. is there. The rear transparent substrate 23 of the liquid crystal display element 13 and the front address substrate 15B of the address optical element 12 are formed by the light emitting layer 19
From the viewpoint of diffusibility of light from the above, it is easier to irradiate a predetermined region of the photoconductive layer 29 with the thinnest possible, and from the viewpoint of refraction of light, the refractive index of the rear transparent substrate 23 and the refractive index of the front address substrate 15B are different. Closer is desirable. In this embodiment, the liquid crystal display element 13 of ECB mode is used, but the orientation is not limited to twist nematic, and any of homogeneous, homeotropic and hybrid orientations may be used. TN liquid crystal mode, STN liquid crystal mode using birefringence, dichroic guest-host (GH) liquid crystal mode, SBE / STN using optical interference
It can be applied to liquid crystal display devices such as a liquid crystal mode, a ferroelectric liquid crystal mode, an antiferroelectric liquid crystal mode, and a polymer dispersed liquid crystal mode (PDLC). In addition, although the present invention is applied to the liquid crystal mode having a polarizing plate in this embodiment, a PC (phase transition) liquid crystal mode, a PDLC (polymer dispersed liquid crystal) / GH mode, which does not have a polarizing plate, The present invention can be applied to a cholesteric liquid crystal mode, a PC liquid crystal / GH mode, a PDLC mode in which an alignment film is unnecessary, and the like. In the above embodiment, the linearly polarizing polarization axis is used, but an elliptically polarizing retardation plate may be appropriately arranged to perform multicolor display.

(Embodiment 7) FIG. 20 is a sectional view schematically showing a transmissive display device according to Embodiment 7. This embodiment is a modification of the sixth embodiment, and has a configuration in which an address optical element is formed on one address substrate 15 and the address substrate 15 and the rear transparent substrate 23 of the liquid crystal display element 13 are bonded together. is there. The rest of the configuration is similar to that of the sixth embodiment. In this embodiment, the light emitting layer 1
9 and the photoconductive layer 29 are shortened, and the signal light is emitted from the light emitting layer 1
A structure capable of accurately reaching 9 is preferable.

Further, since the light and heat generated from the backlight system 14 are reduced and transmitted by the rear polarizing plate 27, the deterioration of the light emitting layer 19 can be suppressed and the signal light can be continuously emitted for a long period of time. Here, the row electrode 16 of the address optical element 12 interposed between the light emitting layer 19 and the photoconductive layer 29.
Since it is an anode electrode, it is easy to set it as a transparent electrode such as ITO, and even if the column electrode 20 has a low work function and thus has reflectivity for visible light and signal light, the light emitting layer 1
The signal light of 9 directly reaches the photoconductive layer 29, and the reflected light of the signal light by the column electrode 20 reaches the photoconductive layer 29, so that the light intensity becomes higher, and even a relatively weak signal light is well addressed. Further, visible light of the backlight system 14 can reach the liquid crystal display element 13 through the gap between the column electrodes 20.

(Embodiment 8) FIG. 21 is a sectional view schematically showing a transmissive display device according to Embodiment 8. In this embodiment, the rear polarizing plate 27 in Embodiment 7 is
This is a configuration in which it is interposed between the address substrate 15 and the rear transparent substrate 23. Other configurations are similar to those of the embodiment. In this embodiment, since the rear polarizing plate 27 is incorporated on the liquid crystal display device 13 side, it is possible to prevent the positional deviation of the rear polarizing plate 27 after the arrangement, so that the polarization axis of the rear polarizing plate 27 is displaced. There is an advantage that it does not. The rear polarizing plate 2
7 is located between the address optical element 12 and the photoconductive layer 29, the signal light is set to an amount that does not hinder the arrival at the photoconductive layer 29, or the signal light has high transparency in the wavelength range. A polarizing plate may be applied.

(Embodiment 9) FIG. 22 is a perspective view showing the concept of a transmissive display device according to Embodiment 9, and FIG.
FIG. 3 is a cross-sectional view schematically showing the cross-sectional structure. In this embodiment, the present invention is applied to a transmissive liquid crystal display element. In the figure, reference numeral 11 denotes a display device.
The reference numeral 1 generally comprises an address light element 12, a liquid crystal display element 13, and a backlight system 14.

As shown in FIG. 23, the address optical element 12 is an address substrate 1 made of glass or polymer film.
On the upper surface (rear surface) of 5, a plurality of row electrodes 16 as an electrode group are formed in parallel with each other in the row direction. The row electrode 16 functions as an anode electrode, and
The width is set smaller than the width of the pixel. Row electrode 16
Is transparent to the signal light of the address light element 12 and the visible light of the backlight system 14, and is, for example, IT.
O, tin oxide (SnO2), magnesium oxide (Mg
O) and the like. Polyvinylcarbazole (hereinafter, PVCz) and 2,5-bis (1-naphthyl) -oxydiazole (hereinafter, BN) are formed on the upper surfaces (rear surfaces) of the plurality of row electrodes 16 and the address substrate 15.
D) and a single-layered first organic film 17 having a hole-transporting property.
Is formed with a film thickness of about 1000Å. Then, an electron transporting second organic film 18 made of tris (8-quinolylate) aluminum complex (hereinafter, Alq3) or the like is formed on the first organic film 17 with a film thickness of about 500 Å.
Then, the light emitting layer 19 includes the first organic film 17 and the second organic film 17.
It is composed of the organic film 18.

Further, on the upper surface (rear surface) of the light emitting layer 19, as shown in FIG. 22, a plurality of column electrodes 20 intersecting (orthogonal to) the row electrodes 16 via the light emitting layer 19 are parallel to each other in the column direction. Is formed. The column electrode 20 functions as a cathode electrode and has a physical property of having a lower work function than the anode electrode. For example, MgIn, A
Examples thereof include metal electrodes such as 1Li and MgIn-Al, n-type amorphous silicon (a-Si), and n-type silicon carbide that have transparency to visible and ultraviolet wavelength ranges. This column electrode 20 is also 1 like the row electrode 16.
The width is set narrower than the width of the pixel. Then, a protective film 21 made of a material having transparency to ultraviolet light and visible light, for example, silicon nitride or silicon oxide is formed so as to cover the light emitting layer 19 and the column electrode 20. In the address optical element 12 thus configured, when an electric field is applied between the row electrode 16 and the column electrode 20,
Signal light in the ultraviolet wavelength range of 350 nm to 400 nm is emitted from the portion of the first organic film 17 near the interface with the second organic film 18. The row electrode 16 and the column electrode 20
Is extended to the edge of the address substrate 15 and is a driving IC.
(Not shown). In this way,
The matrix-addressed address optical element 12 is configured.

A rear polarizing plate 27 is arranged on the rear surface of the protective film 21 of the address optical element 12 having such a structure.
The liquid crystal display element 13 combined with the address light element 12 has a display area having an area similar to the entire light emitting area of the address light element 12. The configuration of the liquid crystal display element 13 will be described below with reference to FIG. The liquid crystal display device 13 includes a pair of front transparent substrate 22 and rear transparent substrate 23,
A liquid crystal 25 sealed by a sealing material 24 between these transparent substrates, and a front polarizing plate 26 arranged on the front surface of the front transparent substrate 22.
And is provided. And in this embodiment,
On the opposite inner surface (front surface) of the rear transparent substrate 23, one transparent rear drive electrode 28 made of ITO is formed over the entire display area. In addition, on the front surface of the rear drive electrode 28, as shown in FIG.
A rectangular photoconductive layer 29 is formed, one for each region (pixel region) of the dot portion d shown by a dotted line in FIG. The photoconductive layer 29 is set so that its occupation rate is smaller than the area of the pixel region. Further, in a region of the rear drive electrode 28 where the photoconductive layer 29 is not formed, an insulating film 37 having substantially the same film thickness as the photoconductive layer 29 is formed so as to be substantially flush with the photoconductive layer 29. Then, on the surface formed by the photoconductive layer 29 and the insulating film 37, a pixel electrode 38 made of ITO is formed for each pixel (dot portion d). That is, each pixel electrode 38 is in a state of being joined to one photoconductive layer 29. By applying an electric field exceeding a threshold value to the liquid crystal between the pixel electrode 38 and the front drive electrode 33 formed over the entire surface of one transparent display area made of ITO, liquid crystal molecules are aligned in a predetermined direction. can do. Further, the pixel electrode 38 has a surface area and a shape that are substantially the same as those of the joined photoconductive layers 29, and shields the photoconductive layer 29 from the wavelength light that is photoelectromotively generated in the photoconductive layer 29. The film 39 is formed so as to overlap the photoconductive layer 29 in plan view. And
On top of that, the post-alignment film 30 is formed so as to cover the entire display area.
Are formed.

The photoconductive layer 29 described above is made of a material that absorbs photons in a specific wavelength range to generate a conductive carrier composed of electron-hole pairs. Examples of such a photoconductive layer 29 include ZnO and amorphous silicon (a-S).
i), amorphous selenium (a-Se), ZnS, Sr
Inorganic semiconductors such as TiO ₃ , GaN, CdS, and SnOx, charge transfer complexes such as polyvinylcarbazole, organic photocarrier generation layers (perylenes, quinones, phthalocyanines, etc.) and organic carrier transport layers (arylamines,
A material such as an organic composite material in which hydrazines and oxazoles) are stacked can be used. When such a material absorbs a photon in a specific wavelength region, a conductive carrier is generated, and the impedance in that region is rapidly reduced, so that the material becomes electrically conductive. Especially,
In the first embodiment, the photoconductive layer 29 is the signal light (ultraviolet light).
ZnO having a light absorption property of absorbing only the light is used. ZnO usually has no absorption in the visible light region and has no photovoltaic power in the visible light region.

On the other hand, the inside facing the front transparent substrate 22 (rear side)
One front drive electrode 33 made of ITO is formed on the entire surface of the display area. Furthermore, the front drive electrode 3
A pre-alignment film 34 is formed so as to cover No. 3. In the liquid crystal display element 13 having such a configuration, the front drive electrode 3
3 and the post-driving electrode 28 can be easily formed.
Throughput can be improved and the manufacturing cost thereof can be significantly reduced as compared with a display element using an FT as a switching element. And, such a liquid crystal display element 13
And the address optical element 12 described above are the liquid crystal display element 1
The address arrangement of the address optical element 12 (arrangement of the intersecting portion of the row electrode 16 and the column electrode 20) is aligned with the pixel electrode 38 of No. 3, and the same dot portion d corresponds. . In addition, the liquid crystal display element 13 and the address light element 12 are assembled so that the signal light enters the corresponding photoconductive layer 29 while maintaining the spatial frequency (in the figure, the light emitting layer 19 and the photoconductive layer 29). The distance between and is shown apart for convenience of explanation, but in the actual device configuration, the signal light is set to a distance that maintains the spatial frequency). Furthermore, FIG.
As shown in, a backlight system 14 is arranged behind the address optical element 12. The backlight system 14 includes a light source 35 that emits visible light and a light guide plate 3.
6 are roughly constituted.

In this embodiment, due to the above-mentioned structure, the signal light emitted from the light emitting layer 19 toward the photoconductive layer 29 is absorbed by the photoconductive layer 29, and the signal light is absorbed by the photoconductive layer 29. It is excited to generate conduction carriers inside it.
Further, the light-shielding film 39 is provided with a property of reflecting light in the wavelength range of the signal light, that is, light in the wavelength range in which the photoconductive layer 29 generates high photoelectromotive force, and the photoconductive from the address optical element 12 is provided. The signal light that has passed through the layer 29 is reflected by the light-shielding film 39 disposed above the photoconductive layer 29, and is again incident on the photoconductive layer 29 to ensure a new conductive carrier in the photoconductive layer 29. Can be generated. Therefore, the light emitting layer 1
Even if the emission intensity of the signal light emitted by 9 is relatively weak, the liquid crystal 25 of the predetermined dot portion d can be driven reliably. Therefore, it is possible to reduce the power consumption on the side of the address optical element 12 that drives the light emitting layer 19. Further, the light shielding film 39 shields the light when light is incident from the outside (front) of the liquid crystal display element 13, and the photoconductive layer 29.
It is possible to prevent photovoltaics due to the incidence of light. As described above, in this embodiment, the photoconductive layer 29 has ZnO having high photovoltaic power in the wavelength range of signal light (ultraviolet light).
Is used. Therefore, with the configuration including the light-shielding film 39, it is possible to prevent a display malfunction from occurring even when light having an ultraviolet light component enters from the outside of the liquid crystal display element 13. Further, by making the area of the photoconductive layer 29 smaller than one pixel and narrowing the widths of the row electrodes 16 and the column electrodes 20, the possibility that the signal light affects the photoconductive layer 29 of the adjacent address is reduced. can do. In this embodiment, the light shielding film 39
However, even if it is configured to have only the light shielding property, it is possible to obtain the advantage of preventing malfunction.

Further, in this embodiment, since the liquid crystal mode in which a color filter having low transmissivity is not used is generally adopted, the light transmissivity is good, and the area occupied by the light shielding film 39 with respect to the pixel area is reduced. By suppressing it, the aperture ratio can be increased. In particular, the cross-sectional area of the photoconductive layer 29 that determines the size and shape of the light-shielding film 39 as a wiring may be extremely smaller than the pixel area, and a high aperture ratio can be achieved. Therefore, high duty driving can be performed, and display with high contrast ratio and high brightness without crosstalk can be realized. In this embodiment, an EC that controls the birefringence of the liquid crystal 25 to change the hue is used.
In addition to B, TN liquid crystal mode, STN liquid crystal mode, guest
Host (GH) liquid crystal mode, PC (phase transition) mode without polarizing plate, PDLC (polymer dispersed liquid crystal) mode,
PDLC / GH mode, cholesteric liquid crystal mode, P
The above-mentioned actions and effects can be obtained by applying the present invention to liquid crystal display devices of various liquid crystal modes such as C liquid crystal / GH mode. Furthermore, in this embodiment, the rear polarizing plate 27 is arranged behind the address light element 12, but it may be arranged between the liquid crystal display element 13 and the address light element 12 as a matter of course. Furthermore, the backlight system 1
If a reflecting plate is provided behind the rear polarizing plate 27 without using 4, it can be used as a reflection type display device, and multicolor display can be performed by using a color filter. In addition,
If a light-shielding film 39 is made of a conductive material, the pixel electrode 38
Since the potential is substantially the same as that, the liquid crystal molecules on the light shielding film 39 can also be aligned in a predetermined direction.

As described above, in the display device 11 of the present embodiment, the width of the electrodes 16 and 20 is made small, so that the light of the backlight system 14 causes the liquid crystal 25 on the pixel electrode 38.
Can be efficiently incident, and display with an extremely high contrast ratio can be realized. In the above embodiment,
Although the photoconductive layer 29 is patterned to have a shape corresponding to the light emitting layer 19, one photoconductive layer 29 may be provided on the entire display surface. In the above-described embodiment, in the case of the reflection type structure, the photoconductive layer 29 does not have to have a peak that produces conductive carriers in the wavelength range of ultraviolet light, and the photoconductive layer has the physical properties of producing conductive carriers in the visible wavelength range. 29 may be set, and the address optical element 12 may also be set to irradiate the signal light in the corresponding wavelength range. At this time, the light-shielding film 39 shields external light such as visible light, sunlight, and light from fluorescent lamps, so that the photoconductive layer 29 does not generate conductive carriers due to such light.

(Embodiment 10) FIG. 24 is a perspective view showing the outline of a display device according to Embodiment 10. In this embodiment, the light emitting layer 19 in the above-described Embodiment 9 is present only in the overlapping portion of the row electrodes 16 and the column electrodes 20, and the light shielding film 39 is not provided. Since the widths of the row electrodes 16 and the column electrodes 20 are narrow as described above, the light emitting area is reduced, and the influence of the signal light on the photoconductive layer 29 in the adjacent pixel region can be prevented. Moreover, since the area of the light emitting layer 19 is small, it is possible to improve the transmittance of light from the backlight system 14. Although the photoconductive layer 29 is patterned in a shape corresponding to the light emitting layer 19 in the above-described embodiment, one photoconductive layer 29 may be provided on the entire display surface. (Embodiment 11) FIG. 25 is a perspective view schematically showing an essential portion of Embodiment 11 of the present invention. This embodiment is
In the above-described second embodiment, as shown in FIG. 25, the post-driving electrodes 28 are formed in a stripe shape so as to correspond to the respective row electrodes 16 of the address optical element 12, and the post-driving electrodes 28 are respectively formed on the post-driving electrodes 28. A photoconductive layer 29 is formed on
The photoconductive layer 29 is also characterized in that it has a stripe shape. The other configurations are substantially the same as those in the first embodiment. Although the photoconductive layer 29 has a stripe shape in this embodiment, only one photoconductive layer 29 may be provided over the entire display surface.

(Twelfth Embodiment) FIG. 26 is a perspective view schematically showing a main part of a twelfth embodiment of the present invention. This embodiment is similar to the eleventh embodiment described above, as shown in FIG.
The post-driving electrodes 28 are formed in stripes so as to correspond to 6 (overlapping in a plan view), and a photoconductive layer 29 is formed over the entire display region so as to cover the post-driving electrodes 28. Has been formed. The other structure is similar to that of the eleventh embodiment.

In this embodiment, since the photoconductive layer 29 is formed over the entire display area, the step difference of the post-driving electrodes 28 formed in stripes can be mitigated by the photoconductive layer 29. Therefore, as shown in FIG. 26, the surface of the post-alignment film 30 provided on the front surface of the photoconductive layer 29 can be made flat, and the post-alignment film 34 is interposed between the pre-alignment film 34 and the post-alignment film 30. The liquid crystal 25 can be oriented uniformly and the display performance can be improved.

(Embodiment 13) FIG. 27 is a sectional view schematically showing a display device according to Embodiment 13 of the present invention. In this embodiment, the present invention is applied to a transmissive liquid crystal display element. Reference numeral 11 in the figure is a display device, and this display device 11 includes an address optical element 12 and an ultraviolet light filter 40.
Liquid crystal display element 13 including a backlight system 1
4 is roughly constituted.

As shown in FIG. 27, the address optical element 12 is formed by arranging a plurality of row electrodes 16 as an electrode group in parallel on the rear surface of the address substrate 15 made of glass. The row electrode 16 functions as an anode electrode, and may be any electrode material that is transparent to signal light and visible light and has a predetermined work function, such as ITO or tin oxide. be able to. On the plurality of row electrodes 16 and the address substrate 15, first polyvinyl carbazole (hereinafter referred to as PVCz) and 2,5-bis (1-naphthyl) -oxadiazole (hereinafter referred to as BND) are formed. The organic film 17 is formed. On the first organic film 17, an aluminum complex (hereinafter, Al
The second organic film 18 made of q3) is laminated so as to be bonded. The second organic film 18 and the second organic film 1
7, and the light emitting layer 19 as an organic EL layer is formed.

Further, on the upper surface (rear surface) of the second organic film 18, as shown in the drawing, a plurality of columns intersecting (orthogonal to) the row electrodes 16 via the light emitting layer 19, and preferably having a light transmitting property. The electrode 20 is formed. The column electrode 20 functions as a cathode electrode and has a characteristic of a low work function value with respect to the row electrode 16, and, for example, silicon carbide (n type),
Hydrogenated amorphous silicon carbide, amorphous silicon (n type), MgIn, AlLi, MgIn / A
It consists of l etc. Then, a light-transmitting protective film 21 is formed so as to cover the light emitting layer 19 and the column electrodes 20.
As the protective film 21, for example, a silicon nitride film can be used. In the address optical element 12 configured as above, when an electric field is applied between the row electrode 16 and the column electrode 20, from the portion near the interface between the first organic film 17 and the second organic film 18, Ultraviolet light (350 to 400 nm) as signal light is emitted. Since it is preferable that the wavelength range of the signal light and the visible light as the display light be as far apart as possible, the signal light should be 350 to 400.
It is desirable to set so that the ultraviolet light in the wavelength range of nm is output. In addition, the row electrode 16 and the column electrode 20 are
It extends to the edge of the address substrate 15 and is connected to a driving IC (not shown). In this way, the matrix-driven address optical element 12 is constructed.

The liquid crystal display element 13 to be combined with the address optical element 12 having the above structure is the address optical element 12
The display area has an area similar to that of the light emitting area. The configuration of the liquid crystal display element 13 will be described below with reference to FIG. The liquid crystal display element 13 includes a pair of front transparent substrates 22.
And the rear transparent substrate 23, and a sealing material 24 between these transparent substrates.
The liquid crystal 25 sealed by the transparent substrates 22 and 2
A pair of front polarizing plate 26 and rear polarizing plate 27, which are arranged with sandwiching 3 between them, and an ultraviolet light filter 40 arranged in front of the front polarizing plate 26 are provided, and the hue is changed by the birefringence of liquid crystal. This is a configuration using ECB cells. In the thirteenth embodiment, ITO is formed on the inner surface of the rear transparent substrate 23 facing the rear transparent substrate 23.
One transparent rear drive electrode 28 is formed over the entire display area. A photoconductive layer 29 is formed on the front surface of the rear drive electrode 28. Further, a post-alignment film 30 is formed so as to cover the photoconductive layer 29.

The photoconductive layer 29 is made of a material that absorbs photons in a specific wavelength range to generate conductive carriers. Examples of such a photoconductive layer 29 include ZnO, amorphous silicon (a-Si), and amorphous selenium (a-S).
e), ZnS, SrTiO3, GaN, CdS, SnO
An inorganic semiconductor such as x, a charge transfer complex such as polyvinylcarbazole, an organic photocarrier generation layer (perylenes, quinones, phthalocyanines, etc.) and an organic carrier transport layer (arylamines, hydrazines, oxazoles, etc.) Materials such as laminated organic composite materials can be used. In such a material, when a photon is absorbed, a conductive carrier is generated and its impedance is rapidly reduced, so that the material becomes electrically conductive. In particular, in the thirteenth embodiment, the photoconductive layer 29 is made of ZnO, which has a characteristic that a photoelectromotive force is generated only in the signal light (ultraviolet light). ZnO generally does not substantially generate photovoltaic in the visible light range.

On the other hand, on the facing inner surface of the front transparent substrate 22,
A single front drive electrode 33 made of ITO is formed over the entire display area. Further, a pre-alignment film 34 is formed so as to cover the pre-driving electrode 33. Further, ultraviolet light is incident on the front surface of the front polarizing plate 26 from the outside, and the photoconductive layer 2 is exposed.
UV light filter 4 for preventing malfunction of 9
0 is arranged. Liquid crystal display device 1 having such a configuration
In No. 3, the front drive electrode 33 and the rear drive electrode 28 can be easily formed, and since it is only necessary to form a film over the entire display area, a comparison is made with a conventional display element using a TFT as a switching element. Therefore, the manufacturing cost can be significantly reduced. Further, as a display element for high time division driving, it is possible to obtain a display device having a good throughput and a high yield. The liquid crystal display element 13 and the address light element 12 are assembled so that the signal light maintains the spatial frequency and enters the photoconductive layer 29. further,
A backlight system 14 is arranged behind the address light element 12. This backlight system 14
Is generally composed of a light source 35 that emits visible light and a light guide plate 36.

In this embodiment, with the above-mentioned configuration, ultraviolet light is prevented from entering the photoconductive layer 29 from the outside, so that display without malfunction can be performed. In particular, in this embodiment, since the configuration is not provided with the color filter, ultraviolet light is more likely to enter from the outside than the liquid crystal display element provided with the color filter. However, since the ultraviolet light filter 40 is provided, It is possible to prevent ultraviolet light from outside from entering the conductive layer 29. Further, the light emitted from the backlight system 14 to the liquid crystal display element 13 is visible light, and thus the photoconductive layer 29.
Since no electric charge is generated in the liquid crystal display, the liquid crystal display performance is not impaired. Furthermore, in this embodiment, liquid crystal display can be performed by substantially simple matrix driving. Further, structurally, there is no area occupied by the active element, so that the transmittance of display light is significantly improved, and a high aperture ratio can be achieved. Further, since the row electrodes 16 and the column electrodes 20 of the address light element 12 have a simple stripe structure,
The processing is extremely easy, and only a small number of lithography steps are required throughout the manufacturing process of the display device, the throughput is good, and the yield can be excellently manufactured. When forming the light emitting layer 19, the first organic film 17 and the second organic film 18 only have to be vapor-deposited or applied in order, so that the manufacture of the address optical element 12 becomes very simple. Since the yield is improved in this way, it is possible to achieve a large screen display with high time division. Further, since there is no occupied area of active elements in one pixel, there is an advantage that high definition can be supported. Moreover, by using the organic EL material as the light emitting layer as in the thirteenth embodiment,
It is possible to realize low-voltage driving as low as that of a TFT-LCD and low power consumption. This is much smaller than plasma based displays. In the first embodiment, since the light emitting layer 19 is used as the signal light generating means and is not used as the display light, relatively weak light emission is sufficient, and the life of the light emitting layer 19 is extended. be able to. Further, in this embodiment,
Although ultraviolet light was used as the signal light, it is also possible to use a wavelength range such as infrared light that deviates from the visible light wavelength range used for liquid crystal display. In addition, in this embodiment, each substrate is a glass substrate, but the light emitting layer 1
Since 9 is made of a flexible organic material, for example, a flexible substrate made of resin can be adopted to provide a flexible display device.

(Fourteenth Embodiment) FIG. 28 shows a fourteenth embodiment.
It is a sectional view showing typically. This embodiment is the same as the second embodiment except that the color filter 31 is provided on the front transparent substrate 2.
The ultraviolet light filter 40 is arranged on the front surface of the light guide plate 36 of the backlight system 14 of the display device provided on the second side. The rest of the configuration is similar to that of the second embodiment described above. This embodiment is particularly effective when using the backlight system 14 containing a large amount of ultraviolet light components that generate charges in the photoconductive layer 29 during light emission, and prevents malfunction of the photoconductive layer 29 due to backlight light. can do. Since this embodiment includes the color filter 31, the incidence of ultraviolet light from the outside is suppressed. The other actions and effects are similar to those of the second embodiment.

(Fifteenth Embodiment) FIG. 29 shows a fifteenth embodiment.
3 is a cross-sectional view of the transmissive display device of FIG. In this embodiment, the display device 11 is such that the address optical element 12 and a part of the liquid crystal display element 13 are integrally formed on the address substrate 15 made of glass by using a film forming technique and a patterning technique. In this embodiment, the address optical device 1
In the second manufacturing process, since the substantial photolithography process is only the process of patterning the two layers of the column electrodes 20 and the row electrodes 16 in a stripe shape, it can be formed very easily as a manufacturing method of a display device. it can. First, the row electrode 16 is obtained by sputtering an anode electrode material and then patterning it using a photolithography technique. After that, the first organic film 17 and the second organic film 18 are laminated by using, for example, spin coating or printing. The column electrodes 20 are formed by sputtering the cathode electrode material and then patterning. Second organic film 18 and column electrode 2
An insulating film 41 made of SiN is flatly formed on the surface of 0 using, for example, a low temperature CVD method. A post-driving electrode 28 made of ITO is formed on the entire surface of the insulating film 41, and a photoconductive layer 29 is formed on the post-driving electrode 28 by a sputtering method or a CVD method (a film forming method using a material of the photoconductive layer). Is selected). A post-alignment film 30 is applied on the photoconductive layer 29. Further, on one surface of the front transparent substrate 22, a front drive electrode 33 is formed of ITO, and a front alignment film 34 is applied on the front drive electrode 33. A rear polarizing plate 27 is arranged on the rear surface of the address substrate 15, and a front polarizing plate 26 is arranged on the front surface of the front transparent substrate 22. The two substrates are assembled so that the alignment films face each other and a liquid crystal injection space is formed with a sealing material (not shown) at a predetermined interval. The liquid crystal 25 is filled in the liquid crystal injection space. In the display device thus formed, the portion formed by the patterning process is small,
Since other layers may be simply laminated, the yield can be significantly improved. Also, two of the substrates 15 and 22
Since only one sheet is required, low cost and thinning can be realized.

(Sixteenth Embodiment) FIG. 30 shows a sixteenth embodiment.
3 is a perspective view showing an outline of the display device of FIG. In this embodiment, as shown in the figure, the address light element 12 is provided with an anode electrode 8 on the front surface and a cathode electrode 9 on the back surface of each of a plurality of light emitting layers 19 arranged in stripes.
It is formed along the line 9. A rear drive electrode 28 is formed on the front surface of the address substrate 15 over the entire display area, and a photoconductive layer 29 is similarly laminated on the entire front surface of the display area. A rear alignment film (not shown) is formed on the front surface of the photoconductive layer 29. Further, a plurality of front drive electrodes 33 that are orthogonal to the light emitting layer 19 in a plan view are formed on the rear surface of the front transparent substrate (not shown). In such a structure, the light emitting layer 19 emits light in one strip.
With this light emission, the photoconductive layer 29 is also photoexcited in a band shape. Then, by selectively driving the predetermined front drive electrode 33, the liquid crystal 25 in the overlapping portion of the excited photoconductive layer 29 and the front drive electrode 33 is driven.

In this embodiment, the address substrate 1
5, an anode electrode material film, a second organic film (not shown), a second organic film (not shown), and a cathode electrode material film are sequentially formed on the film 5, and then the patterning is performed once for the anode optical device. There is an advantage that 12 can be formed. Further, there is an advantage that gradation display can be made possible by controlling the voltage applied to the front drive electrode 33. In the address optical element 12 having such a structure, each layer of the light emitting layer 19 can be formed by roll-to-roll as well.
The film can be finely divided to form a film when the display device is enlarged.

(Embodiment 17) FIG. 31 shows Embodiment 17.
32 is a cross-sectional view of the display device shown in FIG. This embodiment is an example in which the present invention is applied to a display device using an EL display element as a driven body. Reference numeral 11 in the drawing is a display device, and the display device 11 is roughly composed of an address light element 12 and an EL light element 42.

The address optical element 12 is shown in FIGS.
, A plurality of row electrodes 1 as an electrode group are formed on the rear surface of the address substrate 15 made of glass or polymer film.
6 are arranged in parallel. This row electrode 16
Is an electrode material that functions as an anode electrode and is light-transmissive and has a predetermined work function. For example, ITO or tin oxide can be used. Polyvinylcarbazole (PVCz) is formed on the plurality of row electrodes 16 and the address substrate 15 (rear surface),
5-bis (1-naphthyl) -oxadiazole (BN
D) and a hole transport layer and a first organic film 17 as a substantial light emitting portion. A second organic film 18 as an electron transporting layer made of an aluminum complex (hereinafter, Alq3) is laminated on the first organic film 17 (rear surface) so as to be bonded. The second organic film 18 and the first organic film 17 form a light emitting layer 19 as an organic EL layer.

On the upper surface (rear surface) of the second organic film 18, a plurality of column electrodes 20 intersecting (orthogonal to) the row electrodes 16 via the light emitting layer 19 are formed, as shown in the figure. . This column electrode 20 is made of, for example, light-reflective MgIn, A
It is made of Li, MgIn / Al or the like and functions as a cathode electrode. Address optical element 12 configured in this way
In the above, when the electric field is applied between the row electrode 16 and the column electrode 20, the second organic film 1 in the first organic film 17 is
From the portion near the interface with 8 the ultraviolet light (35
0-400 nm). The photoconductive layer 2 described later
Since 9 forms an electric charge with respect to light in the wavelength range of 350 nm to 400 nm, it is preferable that the wavelength range of the signal light and the visible light as the display light are as far apart as possible, and the signal light is 350 to 400 nm. It is desirable to set so that the ultraviolet light in the wavelength range of is output. Also, the row electrode 1
The column electrodes 6 and the column electrodes 20 extend to the edge of the address substrate 15 and are connected to a driving IC (not shown). In this way, the matrix-driven address optical element 12 is constructed.

The EL display element 42 to be combined with the address optical element 12 having such a structure is the address optical element 12
The display area has an area similar to that of the light emitting area. The EL display element 42 is formed on the front upper surface of the address substrate 15. First, on the upper surface of the address substrate 15, for example, ITO, tin oxide, as a cathode electrode,
A plurality of transparent post-driving electrodes 28 made of manganese oxide or the like are formed in stripes. After this, the drive electrode 28 is
It is arranged and formed so as to face each of the row electrodes 16 described above and overlap each other when seen in a plan view. A photoconductive layer 29 is formed on the address substrate 15 and the rear drive electrode 28 so as to cover the entire display area.

This photoconductive layer 29 absorbs photons,
It is made of a material that produces conductive carriers. Examples of such a photoconductive layer 29 include ZnO, amorphous silicon (a-Si), amorphous selenium (a-Se), and Z.
Inorganic semiconductors such as nS and SnOx, charge transfer complexes such as polyvinylcarbazole, organic photocarrier generation layers (perylenes, quinones, phthalocyanines, etc.) and organic carrier transport layers (arylamines, hydrazines, oxazoles, etc.) A material such as an organic composite material in which and are stacked can be used. When such a material absorbs a photon in a specific wavelength range, a conductive carrier is generated, and its impedance is rapidly reduced, so that the material becomes electrically conductive. In particular, in this embodiment, the photoconductive layer 29 has a light absorption property of absorbing only a specific wavelength region,
ZnO that generates conductive carriers is used. ZnO
Usually has no absorption in the visible light range. When ZnO is used as the above material, an organic dye is usually used as a sensitizer in order to extend the photoelectric effect of ZnO to the visible light range. FIG. 3 shows the photovoltaic power of ZnO (indicated by a circle),
3 is a graph showing a photovoltaic spectrum of ZnO using eosin as a sensitizer and the photovoltaic power (indicated by triangles). From this graph, it is understood that ZnO produces conductive carriers only in the ultraviolet light region, and ZnO using eosin as a sensitizer produces conductive carriers even in the wavelength range of 450 to 600 nm.

In this embodiment, amorphous silicon is applied as the photoconductive layer 29, and a doped layer 29A made of amorphous silicon formed by doping a p-type impurity (for example, boron) is provided on the entire surface. There is. The doped layer 29A is the EL for the first display described later.
It is provided to facilitate injection of electrons into the film 44. On the dope layer 29A, a first display E as an electron transport layer made of Alq3, which is the same material as that of the first organic film 17 described above.
The L film 44 is formed on the entire surface. Then, on the first display EL film 44, a second display E as a hole transport layer is formed.
The L film 45 is formed. The second display EL film 45
Is PVCz and B which are the same material as the second organic film 18 described above.
The ND and a light emitting material that emits white light by the ultraviolet light of the EL element 42 are mixed and formed. It should be noted that this luminescent material may be set to have a low concentration above the luminescent region that emits ultraviolet light in the vicinity of the interface with the first display EL film 44 in the second display EL film 45, that is, on the color filter 47 side. desirable. Further, on the second display EL film 45, a front drive electrode 33 as an anode electrode made of, for example, ITO or tin oxide is formed on the entire surface. A color filter 47 is arranged on the front drive electrode 33 so as to correspond to each pixel.

Next, the operation and operation of the seventeenth embodiment will be described with reference to FIG. First, FIG. 4 shows a schematic energy diagram of the address optical device 12 of this embodiment. This energy diagram illustrates the effect on the injection barrier of electrons and holes by mixing BND, which has an electron transporting property rather than PVCz, in the PVCz as the first organic film 17 bonded to the row electrode (anode) 16. .

In FIG. 4, the alternate long and short dash line shows the energy structure peculiar to BND, and the broken line shows the energy structure peculiar to PVCz. In the case of the composite film in which the respective components are mixed in this way, in terms of the transfer of electrons from the electron transport layer side made of Alq3 to the hole transport layer, the respective electrons at the interface between the hole transport layer and the electron transport layer are Considering the affinity, the electron transport layer reflects the physical properties of components having a smaller electron potential. That is, this interface reflects the physical properties of BND, which is an electron transporting dopant. On the contrary, in the movement of holes from the row electrode (anode) 16 side to the electron transport layer, the physical properties of the material having a smaller hole potential are reflected in the ionization potential of the electron transport layer at the interface with the row electrode 17. To be done. That is, PVCz that also functions as a binder is formed at the interface on the electron transport layer side.
The physical properties of will be reflected. In addition, since the energy barrier from the row electrode 16 to the electron transport layer is reflected in the energy barrier of PVCz, HfrommA is relatively small, and holes can be easily injected into the electron transport layer by applying a predetermined voltage. However, it is difficult to inject holes from the electron transport layer to the hole transport layer because the energy barrier HfromAlq3 is large. As a result, the electronic properties of the entire light emitting layer 19 have an energy structure shown by the diagonal lines in the figure when focusing on the injection barrier at the interface. That is,
Regarding the carrier injection barrier, it is considered that mixing BND reduces the energy barrier from the hole transport layer to the electron transport layer by the energy barrier EtoBND, and facilitates the injection of electrons into the electron transport layer. Therefore, light emission is performed near the interface between the electron transport layer and the hole transport layer.
In such an address light element 12, the use of the organic EL layer makes it possible to satisfy the conditions of high-speed response and highly efficient light. Display light-emitting layer 46 of EL display element 42
In the same manner, light is emitted by the same action as described above, but of the light generated in the vicinity of the interface between the second display EL film 45 and the first display EL film 44, the light traveling toward the photoconductive layer 29 side. Enters the photoconductive layer 29 as return light while remaining as ultraviolet light without being affected by the light emitting material. Further, the light traveling toward the color filter 47 side becomes white due to the light emitting material, passes through the color filter 47, is colored into a predetermined color, and becomes display light.

The operation and operation of such a display device will be described below. First, in the address optical element 12,
When a voltage is applied between the row electrode 16 and the column electrode 20 selected by line-sequential scanning, ultraviolet light as signal light is emitted from the light emitting layer 19 toward the photoconductive layer 29. In addition,
At this time, since the light emitting layer 19 and the photoconductive layer 29 are sufficiently close to each other, the signal light can be incident on the photoconductive layer 29 while maintaining a practically sufficient spatial frequency. Therefore, the signal light emitted from the predetermined address does not enter the photoconductive layer 29 in the adjacent dot region to excite the photoconductive layer 29. As described above, the photoconductive layer 29 and the doped layer 54 where the signal light is incident absorb the light in the predetermined wavelength range and become electrically conductive, and are electrically connected to the post-driving electrode 28. As a result, the potential applied between the front drive electrode 33 and the rear drive electrode 28 becomes a predetermined dot of the display light emitting layer 46 formed of the first display EL film 44 and the second display EL film 45. Will be applied to the part. Note that a DC drive voltage, a pulse voltage, an AC voltage, or the like can be used between the drive electrodes. As a result, as described above, the visible light generated by the light emitted from the EL display element 42 is generated toward the front, and at the same time, the ultraviolet light that returns toward the rear is generated. Since this ultraviolet light enters the photoconductive layer 29 and the doped layer 54,
The photoconductive layer 29 is re-excited to newly generate electron-hole pairs. Therefore, the photoconductive layer 29 maintains the conductive state, and the drive voltage is continuously applied to the corresponding liquid crystal 25. While in this state, the display light emitting layer 46 is always driven, so that the display light emitting layer 46 maintains the light emission even when the row electrode 16 and the row electrode 20 on the address optical element 12 side are not in the selected state. Will be done. Therefore, the line-sequential scanning maintains the light emission until the second scanning.

In this embodiment, since the display light emission is maintained until the next line-sequential scanning, good display can be performed. Further, since the address optical element 12 and the EL display element 42 can be formed on the address substrate 15, the display device can be made thin and lightweight. Further, each pixel in the conventional organic EL element has to maintain light emission for one screen in high-duty matrix driving, and therefore the initial voltage must be set extremely high, and therefore the EL display element itself. However, according to this embodiment, the feedback of each pixel is performed by a simple structure without using an active drive represented by a TFT or an element having a memory property such as a ferroelectric liquid crystal. A memory property or appropriate hysteresis due to light is realized, and high-quality display can be realized under a high duty driving condition. For the same reason, in order to obtain a desired display brightness, the brightness required for the EL display element 42 decreases,
A longer life of the display element 42 can be expected. Furthermore, organic E
It is possible to use the low brightness region where the efficiency of the L element is maximized, and as a result, the power consumption of the entire device can be reduced. Furthermore, in this embodiment, since it can be formed on one address substrate 15, the TFT
Further, it is advantageous in increasing the screen size as compared with a ferroelectric liquid crystal display or a plasma display. In addition,
In this embodiment, there is no reduction in the aperture ratio in high definition and miniaturization, which is a concern in a display device using a TFT, and thus it is more advantageous than a TFT drive element in terms of display brightness and efficiency in miniaturization. . In addition, it can be formed by a consistent vacuum process and does not require a high level clean room as a manufacturing process. Further, the patterning and alignment techniques are also very easy compared with the TFT manufacturing process. Further, in this embodiment, the display light emitting layer 46 is formed of the organic EL material, but the inorganic EL is used.
Of course, a material may be used.

In this embodiment, the light emitting material is coumarin 6 (C6) or beryllium (bis (10
-Hydroxybenzo [h] quinolinato)); Bebq
2 and various luminescent materials such as quinacridone can be used. The structural formulas of coumarin 6, Bebq ₂ , and quinacridone are shown below.

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[Chemical 6] Further, in this embodiment, as the hole transport material,
A mixture of PVCz and BND was used.
Cz alone or a material such as 4,4 ′, 4 ″ -tris (3-methylphenylphenylamino) triphenylamine: MTDATA can be used.

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(Embodiment 18) FIG. 33 shows Embodiment 18.
It is a cross-sectional view of a display device according to. This embodiment is characterized in that a dielectric half mirror 48 is arranged on the front surface of the address substrate 15 in the configuration of the above-mentioned seventeenth embodiment. In addition, in this embodiment, the column electrode (cathode electrode) 20 also has light reflectivity. Then, the relation between the distance L between the dielectric half mirror 48 and the column electrode 20 and the wavelength λ of the signal light is (after taking into consideration the refractive index of the material sandwiched between them) L = nλ / 2 (n is It is a positive integer, preferably 1 to 3) to form a microresonator. Thereby, the straightness of the signal light can be improved. The rest of the configuration is the same as in the seventeenth embodiment.

By setting in this way, the light emitting layer 1
The rectilinear light of the signal light generated from 9 resonates, passes through the dielectric half mirror 48, advances straight, and enters the photoconductive layer 29,
Except for the straight traveling light, it cannot pass through the dielectric half mirror 48 and is not incident on the photoconductive layer 29. By such an operation of light, the signal light is resonated to enhance straightness. Therefore, the photoconductive layer 29 located in the dot portion to which the signal light corresponds
It is possible to prevent the crosstalk by surely entering the light source. When light is emitted from the display EL element 42, light traveling backward in the emitted light passes through the photoconductive layer 29, is reflected by the dielectric half mirror 48, and is incident on the photoconductive layer 29 again. If the light traveling rearward has a wavelength that is absorbed by the photoconductive layer 29, the returned light of the sixteenth embodiment is incident on the photoconductive layer 29 again and the photoconductive layer 29 can be surely kept conductive. is there. The other operations and effects of this embodiment are the same as those of the above-described sixteenth embodiment.

(Embodiment 19) FIG. 34 shows Embodiment 19.
3 is a cross-sectional view showing the display device of FIG. In this embodiment, in order to adjust the distance between the dielectric half mirror 48 and the column electrode 20 to L = nλ / 2 in the eighteenth embodiment,
A feature is that an adjustment film 49 made of, for example, SiN and having a predetermined film thickness is interposed between the dielectric half mirror 48 and the row electrode 16. In this embodiment, the dielectric half mirror 48 is formed on the rear surface of the address substrate 15 in advance, and the adjustment film 49 is adjusted to a desired thickness on this surface, so that the space between the column electrode 20 and the dielectric half mirror 48 is reduced. Thus, the microresonator can be surely constructed. Further, by adjusting the film thickness of the adjustment film 49, it is possible to design the resonator structure so as to match the wavelength of the signal light excited by the address optical element 12.

(Embodiment 20) FIG. 35 shows Embodiment 20.
It is a cross-sectional view of a display device according to. This embodiment is characterized in that the address optical element 12 is formed on the address substrate 15, the EL display element 42 is formed on the EL substrate 50 made of glass, and the address substrate 15 and the EL substrate 50 are bonded to each other. According to this embodiment, the address light element 12 and the EL display element 42 are separately formed, which is advantageous in that the overall yield can be improved. Note that the other configurations, operations, and effects are similar to those of the seventeenth embodiment described above.

(Embodiment 21) FIG. 36 shows Embodiment 21.
3 is a cross-sectional view showing the display device of FIG. In this embodiment, the address optical element 12 is formed on the rear surface side of the address substrate 15, and the EL display element 42 is formed on the front surface side. First, a row electrode 61 is formed on the rear surface of the address substrate 15, and the row electrode 61 functions as a cathode electrode.
Then, an electron injection layer 51 made of p-type silicon carbide is formed so as to cover the address substrate 15 and the row electrode 61. On the rear surface of the electron injection layer 51, A
The second organic film 18 made of lq3 and the first organic film 17 made of PVCz and BND are formed by a wet film forming method such as dip coating or spin coating. The first organic film 17 and the second organic film 18 form a light emitting layer 19 of the address light element 12. Further, on the rear surface of the first organic film 17, column electrodes 62 as anode electrodes are formed in stripes in a direction intersecting the row electrodes 61. Reference numeral 52 in the drawing denotes a protective film 52 formed so as to cover the entire address optical element 12.

On the other hand, on the front surface of the address substrate 15, there is formed a rear driving electrode 28 as a cathode electrode which is opposed to the row electrode 61 in a pair. Also, on its front,
A photoconductive layer 29 made of ZnO is formed. An electron injection layer 53 made of p-type silicon carbide is formed on the front surface of the photoconductive layer 29. Further, on the front surface of the electron injection layer 53, a first display EL film 44 made of Alq3 as an electron transport layer and a second display layer made of PVCz, BND and a light emitting material as a hole transport layer are sequentially formed. The EL film 45 is laminated by a wet film forming method such as dip coating or spin coating. Here, the light emitting material is located in a recombination region of electrons and holes in the first display EL film 44, and is composed of a material that emits red, green, and blue depending on the intersection of the electrodes 28 and 33. To be done. Second display E
On the front surface of the L film 45, a transparent front drive electrode 33 such as ITO serving as an anode electrode is formed over the entire display area.

(Embodiment 22) FIG. 37 shows Embodiment 22.
It is a cross-sectional view of a display device according to. In this embodiment, the front drive electrode 63 on the EL display element 42 side in the above-described Embodiment 20 is formed of a cathode electrode material, and the rear drive electrode 64 is formed.
Is formed of an anode electrode material, and the electron injection layer 53 is arranged so as to be bonded to the rear surface of the front drive electrode 33 accordingly. It is characterized in that it is formed and the first display EL film 44 is made of Alq3, and the other structure is the same as that of the nineteenth embodiment. In each of the above embodiments, the row electrode 16 of the address optical element 12 is used.
The column electrodes 20 and the column electrodes 20 may have the opposite configurations.

(Embodiment 23) FIG. 38 shows Embodiment 23.
It is a cross-sectional view of a display device according to. In this embodiment, the address optical element 12 and the E
The L display element 42 is characterized by being formed continuously. First, the column electrode 20 is formed on the address substrate 15, then the second organic film 18, the first organic film 17, and the row electrode 16 are sequentially formed, and the protective film 52 is formed thereon. The post-driving electrode 28, the photoconductive layer 29, the electron injection layer 53, and the first display EL are sequentially formed on the protective film 52.
The film 44, the second display EL film 45, and the front drive electrode 33 are formed and configured. In this embodiment, the column electrode 20, the row electrode 16, and the post-driving electrode 28 require a patterning step, but the other steps are merely film forming steps. Therefore, there is an advantage that manufacturing is dramatically facilitated. The other actions and effects are substantially the same as those of the above-described sixteenth embodiment.

Although the respective embodiments of the present invention have been described above, the present invention is not limited to these.
Various design changes accompanying the gist of the configuration are possible. For example, of the above-described embodiments, in the embodiment in which the liquid crystal display element is used as the driven body, any liquid crystal display mode can be adopted, and the present invention can be applied regardless of the transmission type or the reflection type. . Further, among the above-described embodiments, in the embodiment in which the EL display element is used as the driven body, various ELs such as organic EL materials and inorganic EL materials
Materials can be used, and the light emitting material contained in the light emitting layer forming the EL display element 42 can be appropriately selected according to the display purpose. Further, the address optical element 12 including the dielectric half mirror according to the eighteenth embodiment.
Can be applied to the address optical element 12 in Embodiments 1 to 16. Further, the adjusting film 49 in the nineteenth embodiment can be similarly applied to the first to sixteenth embodiments. Furthermore, in the first to sixteenth embodiments, the address light element 12 and the liquid crystal display element 13 are separately provided, but the present invention is not limited to this.
The address optical element 12 other than the address substrate 15 may be provided on the rear transparent substrate 23 side of the liquid crystal 25 and the photoconductive layer 29 between the front transparent substrate 22 and the rear transparent substrate 23 of the liquid crystal display element 13.

[0116]

As is apparent from the above description, according to the present invention, the manufacturing cost is low, the aperture ratio is high, the driving characteristics are good, and it is easy to increase the screen size and definition, There is an effect that a display device that simultaneously realizes voltage driving and low power consumption can be obtained. Further, by using, for example, an organic EL material, it is possible to realize a display device having flexibility while making it a film substrate to be thin and lightweight.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an outline of a first embodiment of a display device according to the present invention.

FIG. 2 is a sectional view of the first embodiment.

FIG. 3 is a graph showing the relationship between the wavelength of ZnO and photovoltaic power.

FIG. 4 is an energy diagram illustrating the effect of electrons and holes on the injection barrier.

FIG. 5 (a) shows the liquid crystal display device of Embodiment 1
C is an explanatory diagram showing a state in which a driving voltage is applied, and FIG. 6B is an equivalent circuit diagram showing resistance and capacitance of the liquid crystal and the photoconductive layer in an initial state in which a driving voltage is applied to the liquid crystal display element.

FIG. 6A shows the liquid crystal display device according to Embodiment 1
The equivalent circuit diagram at the time of signal light irradiation in the state which applied C drive voltage, (b) is an equivalent circuit diagram when light irradiation is stopped.

7A is a waveform diagram showing the optical pulse and the effective voltage of the liquid crystal in Embodiment 1, and FIG. 7B is a waveform diagram showing the optical pulse and the effective voltage of the liquid crystal in the entire scanning period.

8A is an explanatory diagram showing a matrix for driving and emitting light from a light emitting layer according to Embodiment 1, and FIG. 8B is a timing chart when the matrix is line-sequentially driven.

FIG. 9A shows a liquid crystal display device according to the first embodiment,
C is an explanatory diagram showing a state in which a driving voltage is applied, and FIG. 6B is an equivalent circuit diagram showing resistance and capacitance of the liquid crystal and the photoconductive layer in an initial state in which a driving voltage is applied to the liquid crystal display element.

10A is an equivalent circuit diagram when signal light irradiation is performed in a state where a drive voltage is applied to the liquid crystal display element according to the first embodiment, and FIG. 10B is an equivalent circuit diagram when light irradiation is stopped.

FIG. 11A is an explanatory diagram showing a state where the driving voltage is 0, and FIG. 11B is an equivalent circuit diagram showing a charge holding state when the driving voltage is 0.

12A is an explanatory diagram showing a state when light is irradiated on a photoconductive layer in a state where a driving voltage is 0, and FIG. 12B is an equivalent circuit diagram showing a state in which charges are erased.

13A is an explanatory diagram showing that one scanning time is divided into an erasing time and a writing time, FIG. 13B is a timing chart showing a driving voltage, and FIGS. 13C to 13E are timing charts of select lines. .

FIG. 14 is a cross-sectional view of the display device according to the second embodiment.

FIG. 15 is a cross-sectional view of the display device according to the third embodiment.

FIG. 16 is a cross-sectional view of the display device according to the fourth embodiment.

FIG. 17 is a sectional view of a display device according to a fifth embodiment.

FIG. 18 is a sectional view of a display device according to a sixth embodiment.

19A to 19C are explanatory views showing the relationship between the orientation processing direction and the polarization axis of the sixth embodiment.

FIG. 20 is a sectional view of a display device according to a seventh embodiment.

FIG. 21 is a sectional view of a display device according to an eighth embodiment.

FIG. 22 is a perspective view showing the outline of a display device according to a ninth embodiment.

FIG. 23 is a sectional view of a display device according to a ninth embodiment.

FIG. 24 is a perspective view showing the outline of a display device according to a tenth embodiment.

FIG. 25 is a perspective view showing the outline of a display device according to an eleventh embodiment.

FIG. 26 is a perspective view showing the outline of a display device according to a twelfth embodiment.

FIG. 27 is a cross-sectional view of the display device of the thirteenth embodiment.

FIG. 28 is a cross-sectional view of the display device of the fourteenth embodiment.

FIG. 29 is a cross-sectional view of the display device of the fifteenth embodiment.

FIG. 30 is a cross-sectional view of the display device according to the sixteenth embodiment.

FIG. 31 is a perspective view showing the outline of a display device according to a seventeenth embodiment.

32 is a sectional view of the display device according to the seventeenth embodiment. FIG.

FIG. 33 is a cross-sectional view of the display device of the eighteenth embodiment.

FIG. 34 is a sectional view of the display device according to the nineteenth embodiment.

FIG. 35 is a sectional view of the display device according to the twentieth embodiment.

FIG. 36 is a sectional view of the display device according to the twenty-first embodiment.

FIG. 37 is a sectional view of the display device according to the twenty-second embodiment.

FIG. 38 is a sectional view of the display device according to the twenty-third embodiment.

[Explanation of symbols]

 11 Display Device 12 Address Optical Element 13 Liquid Crystal Display Element 14 Backlight System 15 Address Substrate 16 Row Electrode 17 First Organic Film 18 Second Organic Film 19 Light Emitting Layer 20 Column Electrode 22 Front Transparent Substrate 23 Rear Transparent Substrate 25 Liquid Crystal 26 Pre-polarization Plate 27 Rear polarizing plate 29 Photoconductive layer 33 Front drive electrode 39 Light-shielding film 40 UV filter 41 Insulating film 42 EL display element 44 First display EL film 45 Second display EL film 46 Display light-emitting layer 47 Color filter 48 Dielectric Body half mirror 49 Adjustment film 50 EL substrate 51 Electron injection layer 52 Protective film 53 Electron injection layer

Claims (23)

[Claims] 1. A light emitting element having a matrix of light emitting regions for generating signal light in a predetermined wavelength region when a predetermined voltage is applied, and a region receiving the signal light from the light emitting device stores electric charges. A display device comprising: a photoconductive layer that generates light; and a display element that is driven and displayed corresponding to a region of the photoconductive layer in which a charge is generated. 2. The light emitting device includes a light emitting layer that generates signal light in the predetermined wavelength range, and a light emitting layer that is transparent to the signal light and is arranged side by side in a first direction on one surface of the light emitting layer. A plurality of first electrodes, and the first electrode on the other surface of the light emitting layer.
Through the light emitting layer in a second direction different from the first direction.
The display device according to claim 1, further comprising a plurality of second electrodes arranged side by side so as to intersect with each other in a matrix. 3. The light emitting device comprises a first electrode and a second electrode.
One of the electrodes is an anode electrode, the other is a cathode electrode, and is an electroluminescent device having a light emitting layer that emits signal light when a voltage is applied between the anode electrode and the cathode electrode. The display device according to claim 1, wherein the display device is a display device. 4. The display device according to claim 3, wherein the light emitting layer of the light emitting element is made of an organic compound. 5. The light emitting layer of the light emitting device comprises a first organic film composed of polyvinylcarbazole and 2,5-bis (1-naphthyl) -oxadiazole, and a first organic film composed of tris (8-quinolylate) aluminum complex. 5. The display device according to claim 4, comprising two organic films. 6. The signal light in a predetermined wavelength range of the light emitting element,
The display device according to any one of claims 1 to 5, which is in a wavelength range between 350 nm and 400 nm. 7. The display device according to claim 3, wherein the anode electrode and the cathode electrode of the light emitting element are transparent to the signal light and visible light. 8. The display device according to claim 3, wherein the cathode electrode is made of n-type silicon carbide or n-type amorphous silicon. 9. The display device has a liquid crystal and the photoconductive layer interposed between a front drive electrode and a rear drive electrode, each of which is transparent to visible light and which is arranged to face each other. The display device according to claim 1, wherein the display device is a display device. 10. The display device according to claim 9, wherein at least one of the front drive electrode and the rear drive electrode is a single electrode formed over the entire display area. 11. The one of the front drive electrode and the rear drive electrode is transparent to the signal light from the light emitting element, and is bonded to the photoconductive layer. The display device according to claim 9 or 10. 12. The charge having a polarity opposite to that of the front drive electrode is accumulated in the photoconductive layer.
~ The display device according to claim 11. 13. The display element includes an anode electrode and a cathode electrode, at least one of which is transparent to signal light from the light emitting element and at least the other of which is transparent to visible light. By applying a voltage between the electrode and the cathode electrode, 401n
The display device according to any one of claims 1 to 8, which is an electroluminescent element having a light emitting layer that emits visible light in the range of m to 800 nm. 14. The display device according to claim 13, wherein the light emitting layer of the display element is made of an organic compound. 15. The first organic layer, wherein the light emitting layer of the display device comprises polyvinylcarbazole, 2,5-bis (1-naphthyl) -oxadiazole, and a light emitting material that emits visible light between 401 nm and 800 nm. A film and a second organic film composed of a tris (8-quinolylate) aluminum complex,
15. The display device according to claim 13, wherein the display device comprises: 16. The cathode electrode of the display element,
14. The display device according to claim 13, wherein the display device is made of n-type silicon carbide or n-type amorphous silicon that is transparent to the signal light and visible light. 17. The display device according to claim 1, wherein the photoconductive layer is formed over the entire display area. 18. The photoconductive layer is zinc oxide (ZnO).
The display device according to any one of claims 1 to 17, wherein the display device comprises: 19. The display device according to claim 1, further comprising a backlight provided behind the display element to irradiate the display element with light. 20. The display device according to claim 19, wherein the backlight irradiates light in a wavelength range that does not generate charges on the photoconductive layer. 21. The backlight has a wavelength of 401 nm to 8 nm.
21. The display device according to claim 19, which irradiates visible light in a wavelength range between 00 nm. 22. The display device according to claim 1, wherein the display element includes a color filter. 23. An organic electroluminescent layer for generating signal light composed of light in a predetermined wavelength range excluding the wavelength range of visible light, and an organic electroluminescent layer which is transparent to the signal light and visible light and is provided on the front surface of the light emitting layer. A plurality of first electrodes arranged side by side in one direction, and the first electrode on the rear surface of the light emitting layer, which is transparent to visible light, in a second direction different from the first direction, through the light emitting layer; A light emitting element having a plurality of second electrodes arranged side by side so as to intersect each other in a matrix with a first electrode; and a light emitting element which is transparent to visible light and formed over the entire display region. Between the one front drive electrode and one rear drive electrode that is transparent to the visible light and the signal light and is formed over the entire display area, The photoconductive layer that generates charges only in a predetermined wavelength range of the signal light and the charges of the photoconductive layer are generated A liquid crystal display element located in front of the light emitting element and a liquid crystal displayed corresponding to a region, and visible light located in the rear surface of the light emitting element through the light emitting element. A display device comprising: a backlight for illuminating an element;