KR100630475B1 - Display, Method of Manufacturing the Same, and Method of Driving the Same - Google Patents

Abstract

In the display device, a reflection area composed of a non-light emitting display element in which a liquid crystal display element reflects external light and displaying the light, and a light emitting area composed of a light emitting display element in which the organic EL element directly modulates and display are provided in the display area. . A first substrate and a second substrate are formed to face each other, and both the optical modulator and the light emitting element are provided between the first substrate and the second substrate. As a result, it is possible to provide a display device excellent in visibility and a manufacturing method thereof from outdoor to indoor, while miniaturization and cost reduction.

Description

Display, Method of Manufacturing the Same, and Method of Driving the Same {Display, Method of Manufacturing the Same, and Method of Driving the Same}

1 is a cross-sectional view showing one pixel of the display device according to one embodiment of the present invention.

2 is a graph showing the concept of the present invention, showing a relationship between display environment and power consumption;

3 is a graph showing the concept of the present invention, showing a relationship between display environment and luminance;

4A to 4C are explanatory diagrams showing a manufacturing method of an opposing substrate in the display device;

5A and 5B are explanatory views showing a method for manufacturing a TFT substrate of the display device;

6 is a cross-sectional view showing a display device formed under a black matrix along an anode of an organic EL element having a metal electrode;

FIG. 7 is a cross-sectional view showing a display device formed under a black matrix by forming a layer structure of an organic EL element having a metal electrode; FIG.

8A and 8B are explanatory views showing a state in which the opposing substrate and the TFT substrate of the display device are bonded together;

Fig. 9 is a drive circuit diagram for one pixel in the case where the display device shares and drives the signal lines;

Fig. 10 is a drive circuit diagram showing a modification of the drive circuit for one pixel in the case where the display device shares and drives the signal lines;

11 is a characteristic diagram showing a display state of the display device;

Fig. 12 shows another embodiment of the display device of the present invention, which is a sectional view showing one pixel of the display device;

13A to 13C are explanatory views showing the manufacturing method of the counter substrate in the display device;

14 is an explanatory diagram showing a method for manufacturing a TFT substrate of the display device;

15A and 15B are explanatory views showing a state in which the opposing substrate and the TFT substrate of the display device are bonded together;

Fig. 16 is a sectional view showing another pixel of the display device according to another embodiment of the present invention.

Fig. 17 is a sectional view in the case where a plurality of convex portions of the display device are formed;

18 is a plan view of a display screen in the display device;

Fig. 19A is a plan view showing a structure in which the light emitting area is provided inside the reflecting area when the reflective area and the light emitting area for one pixel are divided in the display device, and Fig. 19B is one pixel for the display device. A plan view showing a configuration in which the light emitting area is provided on the corner side of the reflecting area when dividing the reflective area and the light emitting area,

20 is a block diagram showing another embodiment of the display device according to the present invention, showing the case where an optical sensor is used;

Fig. 21 shows another embodiment of the display device of the present invention, which is a plan view showing one pixel of the display device;

Fig. 22 is a cross sectional view taken along the line A-A in Fig. 21 showing one pixel in the display device;

23 is an overall configuration diagram showing the display device;

Fig. 24 is an explanatory diagram showing a display state of a liquid crystal display element and an organic EL element when the drain voltage Vd is smaller than the liquid crystal threshold voltage Vth (LC) when the display device is in the normally white mode;

Fig. 25 shows a liquid crystal display element and an organic EL when the drain voltage Vd is larger than the liquid crystal threshold voltage Vth (LC) and smaller than the EL threshold voltage Vth (OLED) when the display device is in the normally white mode. Explanatory drawing showing the display state of the device,

Fig. 26 shows a liquid crystal display element and an organic EL when the drain voltage Vd is larger than the liquid crystal threshold voltage Vth (LC) and larger than the EL threshold voltage Vth (OLED) when the display device is in the normally white mode. Explanatory drawing showing the display state of the device,

27 is an explanatory diagram showing a display state of a liquid crystal display element and an organic EL element when the drain voltage Vd is smaller than the common threshold voltage Vth in the case where the display device is normally black mode;

28 is an explanatory diagram showing a display state of a liquid crystal display element and an organic EL element when the drain voltage Vd is larger than the common threshold voltage Vth in the case where the display device is normally black mode;

Fig. 29A is an explanatory diagram showing the luminance state of the liquid crystal display element when the display device is in the normally black mode, and Fig. 29B shows the luminance state of the organic EL element when the display device is in the normally black mode. Explaining,

30 is a signal waveform diagram at the time of driving still another embodiment of the display device in accordance with the present invention;

31 is an explanatory diagram showing another configuration of the voltage-current conversion means;

32A to 32C are signal waveform diagrams at the time of driving still another embodiment of the display device according to the present invention;

33 is a sectional view showing another embodiment of the display device according to the present invention, showing an organic EL light emitting element having a structure including a hole transport layer, a light emitting layer, and an electron transporting layer as an organic EL layer;

34 is a cross-sectional view showing an organic EL light emitting element having a structure composed of a polymer EL material as an organic EL layer;

35A to 35C are cross-sectional views illustrating a method for manufacturing an opposing substrate of the display device shown in FIG. 33;

36A and 36B are cross-sectional views illustrating a method for manufacturing a TFT circuit-side substrate of the display device shown in FIG. 33;

37A and 37B are cross-sectional views showing a step of bonding the opposing substrate and the TFT circuit side substrate of the display device shown in Fig. 33;

38A to 38C are diagrams illustrating a manufacturing method of a counter substrate of the display device shown in FIG. 34;

39 is a cross sectional view showing a method for manufacturing a TFT circuit-side substrate of the display device shown in FIG. 34;

40A and 40B are cross-sectional views showing a step of bonding the opposing substrate and the TFT circuit side substrate of the display device shown in Fig. 34;

41 is a cross-sectional view showing a conventional display device.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device such as a non-light emitting display device such as a liquid crystal display device, a light emitting display device using an organic EL element, or the like, a manufacturing method thereof, and a driving method thereof. In particular, the present invention relates to a display device in which a non-light emitting display area and a light emitting display area are arranged in a display area, a light emitting display device, a manufacturing method thereof, and a driving circuit thereof.

In recent years, portable information terminals (PDAs) are widely used, including mobile phones. Accordingly, the development of information display displays mounted on these terminals has been very successful in recent years.

The display is roughly divided into a non-light emitting display device and a light emitting display device. The former modulates light from an external light source such as sunlight, room light, backlight, or front light by means of a light modulation element, and displays the liquid crystal display element. On the other hand, the latter does not require an external light source, and the display is performed by the light emitting element emitting light by itself, and EL (electroluminescence) has attracted great attention as a representative thereof. Hereinafter, these display apparatuses are demonstrated in detail.

First, in the transmissive liquid crystal display device, which is a non-light emitting display device using an external light source, the backlight is used as a light source, and therefore, the problem remains portable due to the increase in power consumption and enlargement of the shape. Therefore, in order to suppress the power consumption, which is one of the above problems, a reflective liquid crystal display device using external light such as solar light or indoor light is developed by forming a lower electrode of the liquid crystal layer from a metal reflecting light such as aluminum. It is. However, this reflective liquid crystal display device has difficulty in use in a dark place because it uses external light.

In order to solve this problem, a semi-transmissive display device is formed in which the lower electrode of the liquid crystal layer is formed as a half mirror to perform reflective display without using a backlight in a bright environment, and transmit a transmissive display by lighting a backlight in a dark place. It became. However, in the transflective display device, since the opposite characteristics of the light reflecting portion and the light transmitting portion are used, the light transmissive efficiency is low and it is not a definite improvement for reducing power consumption.

Therefore, the inventors have devised a liquid crystal display device which can be used as a reflection type which does not use a backlight under bright environment, and can be used as a transmissive type by turning on the backlight in a dark place (US Patent No. 6,195,140 B1, Patent Date: February 27, 2001, see [= Japanese Patent Application Laid-Open No. 1999-101992 (published: April 13, 1999)].

This liquid crystal display device, unlike a conventional liquid crystal display device using a reflector plate having a thin film thickness and having a semi-transmissivity, divides each display pixel in the liquid crystal display device into two areas, a reflection area and a transmission area. That is, in the above liquid crystal display device, a reflective electrode is formed as one region of each display pixel to form a reflective region, while a transmissive electrode is formed in another region of each display pixel to form a transmissive region. In addition, the thickness of the liquid crystal layer in the reflective region and the thickness of the liquid crystal layer in the transmissive region are different. This makes it possible to realize the optimum brightness in each of the reflective and transmissive regions.

However, in the pixel division type liquid crystal display device, the backlight light is irradiated to the entire area of each pixel from the rear, whereas only the transmission area of each pixel is used. Therefore, there exists a subject that the utilization efficiency of backlight light is low. In particular, when the area ratio of the reflective electrode is high, the transmission area is inevitably narrowed, so that the utilization efficiency of the backlight light is low.

The pixel division type liquid crystal display device disclosed in, for example, Japanese Laid-Open Patent Publication No. 2001-66593 (published: March 16, 2001), which improves the utilization efficiency of its backlight light with respect to the pixel division type liquid crystal display device. There is. In this liquid crystal display device 300, as shown in FIG. 41, first, a transmissive opening 304 is formed in a part of the reflective electrode 303 disposed in each pixel 302 ... in the liquid crystal panel 301. By providing, it is set as the pixel division type liquid crystal display device. In this liquid crystal display device 300, a light emitting element made of an organic EL (electroluminescence) element 310 is used as a backlight, while a light emitting portion 311 of the organic EL element 310 is used. Is not disposed in the entire region of each pixel 302... But only in the region corresponding to the transmission opening 304. Thus, by combining the patterned organic EL element as a backlight, it is possible to improve the utilization efficiency of light and to reduce the power consumption.

Here, the display device using the organic EL element, which is a representative of the light emitting display device, is a light emitting device having a thin and lightweight feature, so that a backlight is unnecessary like a liquid crystal display device and can be used even in a dark environment. Since almost everything is used for display, the light utilization efficiency is also high. However, the display device using this organic EL element always needs to emit light, and in order to raise the display quality in a particularly bright environment, it is necessary to increase the amount of emitted light, which makes it difficult to reduce power consumption.

However, in the pixel division type liquid crystal display device shown in FIG. 41, since the organic EL element 310 is disposed outside the liquid crystal panel 301 as a light emitting element, the transmission aperture 304 of the reflection electrode 303 is provided. And a phase difference plate 305, a polarizing plate 306, two glass substrates, that is, a glass substrate 307 and a glass substrate 312, between the organic EL element 310. Currently, a typical pixel pitch is on the order of 80 microns, but in this case, the width of the transmissive opening 304 is from one half to one sixth, from about 15 microns to 40 microns. On the other hand, the thickness of the polarizing plate 306 is about 300 microns and at the same time the glass of 500 to 700 microns thick is formed into the glass substrate 307 of the liquid crystal panel 301 and the glass substrate 312 of the organic EL element 310. Chapter 2 exists. Therefore, the distance between the transmission opening 304 of the reflective electrode 303 and the organic EL element 310 may be 1300 microns to 1700 microns. Therefore, even if the light emission part 311 ... of the organic EL element 310 is provided in the position corresponding to the transmission opening part 304 ..., it is the organic electroluminescent element 310 in the transmission opening part 304 ... It is impossible to inject all the light emitted from the light emitting portion 311 of (). Therefore, there is also a problem that the irradiation efficiency of the organic EL element 310 is not good.

Incidentally, in the pixel division type liquid crystal display shown in Fig. 41, there is no change in overlapping the substrates. And with respect to its thinning, there remains a problem that the sum of the thickness of the liquid crystal display device and the thickness of the organic EL element is the limit. In addition, in the configuration of Fig. 41, the transparent opening 304 and the forming portion of the organic EL element 310 of the liquid crystal display must be positioned and fixed. For this purpose, a dedicated positioning device and a mechanism for fixing are required, resulting in an increase in the number of parts and an increase in cost.

On the other hand, as described above, the reflective liquid crystal display device has been developed for the purpose of improving visibility in the outdoors, and is excellent in visibility in the outdoors with strong external light, but cannot be used indoors or at night. Therefore, in the reflection type liquid crystal display device, the front light which introduces illumination light from the front surface as a substitute for external light is also considered. As an example of using an organic EL element for this front light, for example, there is one disclosed in Japanese Laid-Open Patent Publication No. 2000-75287 (published date: March 14, 2000). However, also in this case, there is a problem that the whole becomes thick due to the thickness of the display device and the auxiliary light source, as in the case of introducing a backlight into the transmissive liquid crystal display device.

As described above, by forming the liquid crystal display element and the organic EL element on one substrate, it is possible to compensate for the respective defects and to perform the optimal display under various environments.

However, in the above display device, if the liquid crystal display element and the organic EL element are simply formed on one substrate, the wiring and the driving circuit in the substrate become complicated, and the yield and cost at the time of manufacture become a problem.

On the other hand, as a separate problem, with respect to a light emitting display device having an organic EL element as a light emitting element, the following problems exist at the time of manufacture.

For example, Japanese Laid-Open Patent Publication No. 2000-173770 (published: June 23, 2000) includes a TFT (Thin Film Transistor) circuit, which is a driving circuit of an organic EL element, on a substrate and a cathode thereon. A part of the organic layer which forms a metal electrode and an organic EL layer which becomes a (cathode) is formed, an anode electrode (anode) is formed in the other board | substrate, a light emitting layer is formed on it, and finally, both of these board | substrates are made Combined, a method is disclosed in which an organic layer is joined at a glass transition temperature or higher by applying heat or pressure.

Further, in Japanese Laid-Open Patent Publication No. 2001-43980 (published: February 16, 2001), an anode electrode (anode) is formed on a substrate (may be a TFT substrate), and an organic EL layer is sequentially formed thereon. After laminating a hole injection layer, a hole transport layer, and a light emitting layer, the method of forming a transparent conductive layer after forming an extremely thin metal having a low work function as a cathode is disclosed.

In either of the above publications, the light emitted from the organic EL element is not emitted from the side of the substrate on which the circuit for driving the organic EL element is formed, but from the side of the counter substrate or the protective layer set opposite thereto. It is possible. As a result, since the emitted light is not shielded by the circuit pattern as compared with the case where it is emitted to the circuit formation side, the aperture ratio can be increased, which is effective for improving the luminance and luminous efficiency, and improving the lifetime and reliability.

On the other hand, since the driving circuit forming side can form a circuit up to an area that has conventionally been covered by the opening, the circuit design can be spared, thereby realizing reliability and yield improvement, and enabling the formation of a circuit with improved functions. In an effective way. Specifically, in Japanese Laid-Open Patent Publication No. 2000-173770, the driving circuit side and the light emitting layer side are formed separately, and in Japanese Laid-Open Patent Publication No. 2001-43980, the cathode electrode is made very thin. It is realized by forming.

Here, it is preferable not to mix water especially with respect to organic electroluminescent element from a viewpoint of the reliability of a light emitting function. In addition, the organic conductor may cause performance deterioration by acceptor doping by oxidation. In addition, the metal used as the cathode is made of a material having a low work function such as magnesium (Mg), lithium (Li), calcium (Ca), etc., and therefore is particularly sensitive to oxidation and difficult to form.

As described above, the organic EL device has a simple structure, but the material to be used tends to greatly influence its performance depending on the environment. Therefore, in the case of forming the organic EL element, it is preferable to form all of them in an environment in which moisture and oxygen are blocked as much as possible, and simultaneously form a layer for protecting the light emitting layer.

In this regard, in Japanese Laid-Open Patent Publication No. 2000-173770, since the bonding is performed in a part of the organic layer forming the organic EL element, the bonding is likely to be exposed to an atmosphere with moisture and oxygen, Reliability is a problem. In addition, since all the organic layers which form an organic electroluminescent element use about 1000 micrometers thin film, film quality or a performance is carried out in the process of forming a part in both board | substrate side at the time of joining, and raising a temperature beyond glass transition point. The uniformity of may collapse.

Further, in Japanese Laid-Open Patent Publication No. 2001-43980, since there is a metal cathode electrode on the emission light side, there is a transmission loss due to this even though it is very thin. In addition, since the cathode electrode is very thin, the problem of performance deterioration due to the bonding of oxygen containing the transparent conductive layer and the organic conductive layer formed thereon, and the effect of temperature on the light emitting layer at the time of forming the transparent conductive layer are problems.

Further, in Japanese Laid-Open Patent Publication No. 2000-173770, since the anode side is a transparent conductive film, and the resistance value is higher than that of a normal conductor, when a panel is used, power loss caused by the transparent conductive film is caused. There is a problem that luminance unevenness of the screen occurs.

SUMMARY OF THE INVENTION An object of the present invention is to provide a display device having excellent visibility from outdoors to indoors, a manufacturing method thereof, and a driving method thereof while realizing miniaturization and cost reduction.                         

In order to achieve the above object, the display device of the present invention includes a first display area comprising a non-light emitting display element in which a light modulation element reflects external light and displaying the light, and a light emitting element directly modulates a display in the display area. A second display area comprising a light emitting display element is provided, and these first display areas and second display areas are provided in parallel.

Therefore, since the light emitting element emits light by itself toward the display surface side and displays it directly, the light emitting element is not used as a backlight or a front light as in the related art. As a result, the utilization efficiency of light from the light emitting element can be increased, and the thickness of the display device is also reduced. That is, since the thickness of the backlight is usually about 3 to 6 millimeters, the advantage of thickness reduction due to the unnecessary backlight is very large. In addition, the need for a backlight means that a polarizer, a retardation plate and a glass substrate, which are conventionally provided between the rear panel and the backlight of the liquid crystal panel, also become unnecessary. Therefore, even if these polarizing plates, retardation plates, and glass substrates become unnecessary, the thickness of the display device can be made thinner.

In addition, since the patterned light emitting device backlight does not need to be positioned and fixed, such a dedicated device and a fixing mechanism can be omitted, thereby making it possible to realize cost reduction due to a reduction in the number of parts and a reduction in process. .

Further, the advantage that the backlight, the polarizing plate and the retardation plate on the back side are not necessary is not only the thickness of the entire display device is thinned. That is, the reduction of the member scores can reduce not only the material cost but also the cost required for assembling or inspecting each member, thereby lowering the manufacturing cost of the entire display device.                         

In addition, in the display device of the display area division method such as the pixel division method such as the present invention, it is possible to arbitrarily design the ratio of the first display area and the second display area to some extent. For this reason, it is common to enlarge the ratio of the 1st display area which is a reflection area when it is made to use for mobile devices, such as a cellular phone and an information portable terminal (PDA), for example. For example, when 80% of the pixel area of the display pixel is the reflection area, the second display area, which is the light emitting area, becomes 20%, so that the light emitting area of the light emitting element is at most one fifth of the pixel area. This means that it is possible to realize a reduction in power consumption.

Therefore, it is possible to provide a display device excellent in visibility from outdoors to indoors while miniaturizing and reducing costs.

The display device of the present invention further includes a first substrate and a second substrate facing each other, and both the light modulation element and the light emitting element are provided between the first substrate and the second substrate. For this reason, since both an optical modulation element and a light emitting element are accommodated between a 1st board | substrate and a 2nd board | substrate, the thickness of a display apparatus can be reliably made thin.

In the display device of the present invention, the light modulation layer of the light modulation element and the light emitting layer of the light emitting element are provided as the same layer in the display device described above. Note that the same layer is not necessarily the same level, but includes a state in which the light emitting layer of the light emitting element is included in the light modulation layer of the light modulation element.

According to the above invention, since the light emitting element is provided in the same layer as the light modulation layer of the light modulation element, the light emitting element can be accommodated within the range of the thickness of the non-light emitting display element made of the conventional light modulation element. As a result, it is possible to reliably reduce the thickness of the display device.

In addition, the display device of the present invention comprises a first display area comprising a non-light emitting display element in which a light modulation element reflects external light and displaying the light in the display area, and a light emitting display element in which the light emitting element directly modulates and displays the light. A second display area is provided in parallel with each other, and includes a first substrate and a second substrate that face each other. Both the light modulation element and the light emitting element are provided between the first substrate and the second substrate. In the second display area, light modulation layers of the light emitting device and the light modulation device are sequentially stacked on the first substrate.

According to the above invention, a light modulation layer of the light emitting element and the light modulation element is sequentially stacked on the first substrate in the second display area. For this reason, since both a light modulation element and a light emitting element are accommodated between a 1st board | substrate and a 2nd board | substrate, the thickness of a display apparatus can be reliably thinned. Further, even if the light modulation layer is laminated on the surface side of the light emitting element, since the light emitting element is provided between the first substrate and the second substrate, all the display light of the light emitting element is emitted to the second display area. For this reason, the utilization efficiency of light becomes very high.

Accordingly, it is possible to provide a display device obtained by securing higher irradiation efficiency and realizing not only the brightness but also the thickness of the display device and the member cost.                         

Further, in the display device of the present invention, each data signal line and each scan signal line for driving each display area arranged in a matrix form as the light modulation element and the light emitting element are shared with each other.

Therefore, when two display elements are formed in the display area, the circuit structure can be prevented from being complicated, and a display device obtained by realizing the yield and cost reduction at the time of manufacture can be provided.

In addition, in the method of manufacturing the display device of the present invention, in manufacturing a display device in which the non-light emitting display element and the light emitting display element are arranged, a driving circuit is formed on the first substrate and the light emitting element is formed on the second substrate. Is formed and then integrated by joining the first substrate side on which these drive circuits are formed and the second substrate side on which the light emitting elements are formed.

For this reason, when manufacturing a display apparatus, a light emitting element and a drive element which drives a light emitting element and a light modulation element can be formed separately. Therefore, when forming the light emitting element, it is possible to avoid the influence of the process temperature, chemicals, gas, etc. at the time of forming the driving element.

In addition, in order to solve the above problems, the display device of the present invention is composed of a light emitting display element alone, the first substrate side of which a driving circuit is formed on the first substrate, and up to two electrodes for light emitting elements on the second substrate. The second substrate side on which the light emitting element including the is formed is joined.

In the display device of the present invention, in the display device described above, the light emitting element is composed of an organic electroluminescent element, and the organic substrate is formed on the second substrate side on which the organic electroluminescent element is formed. After forming up to the cathode electrode in the element, it is joined to the first substrate side.

According to the above invention, in the light emitting display element alone, the second substrate side forming the organic electro luminescence element (hereinafter referred to as "organic EL element") which is a light emitting element is for a light emitting element in an organic EL element. After forming the cathode which is an electrode, it is bonded to the first substrate side.

As a result, the light emitted from the organic EL element can be emitted from the side of the counter substrate or the protective layer which is set to face the substrate instead of the substrate side on which the driving circuit for driving the organic EL element is formed. For this reason, since the said light emission direction is the same as the said prior art, it has the following fundamental advantages equally compared with the structure which exits to the drive circuit formation side.

First, the first substrate side on which the driving circuit is provided and the organic EL element can be formed separately. For this reason, since a manufacturing process can be formed independently each, it is not influenced by temperature, a gas, a chemical | medical agent, etc., and reliability improves.

Moreover, light can be emitted to the 2nd board | substrate side in which the organic electroluminescent element was formed by the said structure. As a result, the light emitting area can be extended and set without being influenced by the opening ratio of the driving circuit side, thereby achieving high luminance. In addition, since the light emitting area is large, the amount of current per unit area for obtaining the same luminance can be suppressed, so that the power consumption is reduced by prolonging the life and improving the luminous efficiency.

In addition, since there is no light output on the first substrate side on which the driving circuit is formed, the first circuit side can form the driving circuit on the entire surface. Therefore, the size of the TFT (Thin Film Transistor) of the drive circuit can be freely set or a margin can be provided in the TFT formation region, whereby a circuit for fine control can be formed. In addition, since there is room in the wiring width, the reliability of the driving circuit can be improved, and the yield is improved.

In addition, in the driving method of the display device of the present invention, by using a display device in which a non-light emitting display element and a light emitting display element are arranged, one field which is a unit time of a video signal in each display area is divided into a plurality of, It is a method of turning on / off an optical modulation element or a light emitting element for each division period.

According to the above invention, in the case of driving a display device in which a non-light emitting display element and a light emitting display element are arranged, one field is divided into plural, and the light modulation element or light emitting element is turned ON and OFF in each division period. It is possible to control the overall ON time of the light modulation element or the light emitting element in one field, and also to increase the types of the lighting patterns thereof and to drive them efficiently.

In addition, by controlling the ON time of the light modulation element or the light emitting element in this manner, the gray scale of the video signal can be displayed.

Therefore, when two display elements are formed in the display area, a circuit structure is prevented from being complicated, yield and cost can be reduced at the time of manufacture, and a display method can be driven with high efficiency. Can be provided.

Still other objects, features, and advantages of the present invention will be fully understood from the description below. Further advantages of the present invention will become apparent from the following description with reference to the accompanying drawings.

First, the outline of the present invention will be described.

According to the display device of the present invention, a non-light emitting display element for reflecting external light and displaying the self-luminous light emitting element is incorporated in the same display device. As a result, it is not necessary to install a separate light source such as a backlight, so that low power consumption and miniaturization can be realized at the same time. In addition, when the non-emission display element and the self-emission light emission display element are incorporated in the same display device, manufacturing processes of members such as electrodes, wiring, driving elements, and insulators can be common, so that light sources such as backlights are conventionally manufactured. And the time and cost required for assembly and the like can be greatly reduced.

Hereinafter, the operation and effects of the present invention will be described in detail.

First, as described above, in general, a display is classified into a non-light emitting display device and a light emitting display device. A non-light emitting display device modulates light from an external light source such as sunlight, room light, backlight, or front light by passing it through an optical modulator that is a non-light emitting display device. There are a reflection type having reflecting means for reflecting light from a light source and a transmission type having no reflecting means. On the other hand, the light emitting display device is a display device having a light emitting element. Usually, a part called a light emitting element or a light emitting layer emits light self-emission. In addition, here, control of the transmitted light in the said optical modulation element is called light modulation, and control of light emission in a light emitting element is called direct modulation.

However, in the case of a transmissive non-luminescent display device typified by a transmissive liquid crystal display device, the luminance of backlight light is usually constant from dark display to bright display and is always lit. Therefore, the transmissive non-luminescence display always consumes power from an external light source. In the transmissive non-luminescent display device, since power supply and control are required for the light modulation element and the backlight, respectively, the number of parts is large, and the miniaturization is difficult, and it is difficult to reduce the cost.

On the other hand, the light emitting display device represented by the EL display device modulates the light emission luminance, so that the power consumption is different in the dark display and the light display.

Here, the case where these transmissive non-emission display elements or light emitting display elements and reflective non-emission display elements are incorporated in the same panel and both are used for display is compared with the present invention. That is, the display device of the present invention is compared with a conventional display device in which a transmissive non-light emitting display element and a reflective non-light emitting display element are incorporated, that is, a pixel split liquid crystal display device as described in the related art.

In the conventional liquid crystal display device, as indicated by the broken line L1 in Fig. 2, since it is necessary to always turn on the backlight which is the light source from the bright environment to the dark environment, almost constant power consumption is required. On the other hand, the display device of the present invention in which the light emitting display element and the reflective non-light emitting display element are incorporated in the same panel can adjust and display the luminance of the light emitting display element according to the surrounding environment. For this reason, as shown by the solid line L2 in FIG. 2, it is possible to lower the light emission luminance in a bright environment and to maximize the use of the reflective non-light emitting display element, while increasing the light emission luminance of the light emitting display element in a dark environment. have. Therefore, in a bright environment, the power applied to the backlight of the conventional non-light emitting display device can be reduced.

Accordingly, the display device according to the present invention can achieve lower power consumption than a display device in which a transmissive non-light emitting display element and a reflective non-light emitting display element are incorporated in a bright environment. Improvement can be realized. In addition, since the display device of the present invention does not need to provide a backlight separately, the display device can be made thinner and smaller in size, and power supply means and control are unnecessary as compared to the conventional liquid crystal display device. have.

When the display device according to the present invention is compared with the display device of only the light emitting display element, it is as shown in FIG. That is, as shown by the broken line L1 'in Fig. 3, in the case of the display device composed of only the light emitting display elements, as the environment becomes brighter, it becomes difficult to see the display unless the light emission luminance is increased.

On the other hand, in the display device of the present invention, since the reflective non-light emitting display element improves the display characteristics in a bright environment, the light emitting display element is displayed by reducing the luminance as indicated by the solid line L2 'in FIG. It is possible. This is a concept that has not been used in the conventional light emitting display device alone, and is a brightness control method that can be independently achieved by the configuration of the present invention.

As described above, according to the display device of the present invention, it is possible to set the maximum luminance lower than that of only the light emitting display element, thereby realizing longer life and improved reliability.

EXAMPLE 1

An embodiment of the present invention will be described with reference to FIGS. 1 and 4 to 11 as follows.

As shown in Fig. 1, the display device 50 of the present embodiment includes upper and lower TFT substrates 51 sandwiching the liquid crystal layer 26 as an optical modulation layer and the organic EL (Electro Luminescence) element 60 as a light emitting element. It is formed by the opposing substrate 52. The lower side is a TFT (Thin Film Transistor) substrate 51 formed on an insulating substrate 21 as a first substrate made of a material represented by glass, and a reflective liquid crystal display element as an optical modulation element for each display pixel ( A liquid crystal TFT element 22 for driving 20 and an EL TFT element 42 for driving a light emitting organic EL element 60 as a light emitting element are formed. While these liquid crystal TFT elements 22 and EL TFT elements 42 can be driven independently, they can also be driven by sharing signal lines.

On the other hand, on the upper side, the insulating substrate 29 as the transparent second substrate made of glass, the color filter layer 28 formed on the insulating substrate 29, the black matrix 33, and the optical modulation element A counter electrode 27 serving as a display surface side electrode, an anode 65 serving as an electrode for a light emitting element and a display surface side electrode of a light emitting element, a hole transport layer 64, a light emitting layer 63, an electron transport layer 62, and an electrode for a light emitting element An opposing substrate 52 composed of an organic EL element 60 composed of a cathode 61 as a cathode, a polarizing plate 32, and a retardation plate 31 is provided.

Here, in the present embodiment, the organic EL element 60 is provided on the same layer as the liquid crystal layer 26 which is the light modulation layer of the liquid crystal display element 20, and the liquid crystal layer (on the light exit side of the organic EL element 60). 26) does not exist.

That is, in the display device 50 of the present embodiment, external light incident from the display surface side is reflected by the pixel electrode 25 of the liquid crystal display element 20 in the portion of the liquid crystal display element 20 and modulated in the liquid crystal layer 26. And a light emitting area 12a as a second display area which emits light to the display surface side by self-emission from a portion of the organic EL element 60 and as a display area as a first display area to display. It is added to every display pixel.

In the display device 50 of the present embodiment, the light emitted from the organic EL element 60 is less likely to pass through the liquid crystal layer 26. For this reason, since the outgoing light of the organic EL element 60 is not scattered or absorbed by the liquid crystal, the luminance decrease is unlikely to occur.

The organic EL element 60 is formed on the anode 65 of the opposing substrate 52 in this embodiment. This means that the organic EL element 60 of the present embodiment can be manufactured in a process separate from the TFT circuit.

That is, the organic EL element 60 is formed on the opposite substrate 52 side, and the light of the formed organic EL element 60 is emitted to the opposite substrate 52 side. For this reason, when forming the counter substrate 52, the hole transport layer 64, the light emitting layer 63, and the electron transport layer 62 are sequentially made from, for example, a transparent anode 65 made of indium tin oxide (ITO). ) And the cathode 61 can be formed, and a conventionally proposed forming method can be used, and since there is no driving circuit on the opposite substrate 52 side, the opening ratio of the organic EL element 60 is not limited by the driving circuit. Therefore, an opening ratio close to 100% is obtained.

In addition, since the TFT manufacturing process and the manufacturing process of the counter substrate 52 are separated, water and a chemical liquid are used, which cause the influence of heat generated in the TFT manufacturing process, and in particular, deterioration of characteristics of the light emitting layer 63 using an organic material. It can be separated from photolithography and etching process.

Therefore, it is an advantage in maintaining the performance of the organic EL element 60 that the organic EL element 60 can be formed separately from the TFT substrate 51.

Here, the light emitting layer used in the present embodiment does not matter whether a low molecular type EL material or a high molecular type EL material is used. The organic EL element 60 shown in FIG. 6 shows an application example of the light emitting layer 63 using a low molecular type EL material, and further provides the electron transport layer 62 and the hole transport layer 64 on both surfaces of the light emitting layer 63. . However, the electron transport layer 62 and the hole transport layer 64 do not necessarily need to be provided. However, in the light emitting layer 63 using the low molecular type EL material, the electron transport layer 62 and the hole transport layer 64 provide light emission. It is preferable from a viewpoint of efficiency.

In the display device 50 of the present embodiment, a conductive contact layer 66 as a convex portion is provided between the pixel electrode 25 and the organic EL element 60 in the TFT substrate 51. As a result, the organic EL element 60, the pixel electrode 25, and the EL TFT element 42 are electrically connected to each other. This conductive contact layer 66 is provided for height adjustment.

Next, the manufacturing method of the display device 50 provided with the organic electroluminescent element 60 which consists of the light emitting layer 63 of the said low molecular weight EL material is demonstrated. First, the case where the counter substrate 52 is formed will be described.

In the light emitting layer 63 of the low molecular type EL material, the organic EL element 60 is generally formed using mask deposition. Therefore, when forming the counter substrate 52, as shown in Fig. 4A, first, the mask 55 is set at a predetermined position on the counter electrode 27 and the anode 65 side of the counter substrate 52. . In the present embodiment, as described later, the method in which the liquid crystal display element 20 and the organic EL element 60 share and drive the signal lines is adopted. Therefore, in view of the structure, a groove is formed between the counter electrode 27 and the anode 65 and is not conductive. However, when driving the liquid crystal display element 20 and the organic EL element 60 independently, the counter electrode 27 and the anode 65 may be turned on.

4B and 4C, the hole transport layer 64, the light emitting layer 63, the electron transport layer 62, and the cathode 61 are sequentially formed through the window 55a of the mask 55. As shown in FIG.

On the other hand, when forming the TFT substrate 51, as shown in Figs. 5A and 5B, the TFT substrate 51 on which the liquid crystal TFT element 22, the EL TFT element 42, and the pixel electrode 25 are formed. After the photosensitive conductive resin is applied onto the mask, mask exposure is performed to leave the conductive resin only in the conductive contact layer 66. Here, in the present embodiment, the pixel electrode 25 is also provided in the region where the organic EL element 60 is disposed. The pixel electrode 25 is made of a conductive film having a reflectivity such as aluminum (Al). However, since the organic EL element 60 emits light only on the display surface side opposite to the pixel electrode 25, the pixel electrode 25 Does not become a problem of light transmission. In addition, since it is not necessary to separately form the reflecting plate on the back surface of the organic EL element 60, the number of steps can be reduced publicly.

In addition, although the said cathode 61 is generally formed with a metal, it is not necessarily limited to this, For example, conductive resin can be used. The conductive resin may be further formed after the cathode 61 is formed of metal or conductive resin. In addition, you may apply | coat an electroconductive resin using an inkjet.

In addition, in this embodiment, since the light emitted from the organic EL element 60 is emitted to the counter substrate 52 side, it is necessary to flow a current from the counter substrate 52 side to the TFT substrate 51 side. Therefore, when the resistance value of the transparent anode 65 formed on the counter substrate 52 side is high, it is also considered to lower the luminous efficiency. Therefore, to solve this problem, for example, as shown in Fig. 6, the metal electrode 65a can be formed along the transparent anode 65 of the organic EL element 60 to reduce the resistance value. As a material which can be used as this metal electrode 65a, low reflectance, for example, titanium (Ti), tantalum (Ta), etc. are preferable. Further, in order to further lower the resistance, for example, as shown in Fig. 7, a metal electrode 65b made of a low resistance metal such as aluminum (Al) and low reflectance such as titanium (Ti) or tantalum (Ta) is used. The metal electrodes 65c may be formed along the black matrix 33 with a layer structure. The low reflection metal is used here because the external light is reflected by the metal electrodes 65a and 65b and the contrast is not lowered. In addition, a metal electrode of the same purpose may be formed along the black matrix 33. In this case, since it does not directly exit to the display surface side shielded from the black matrix 33, it is not limited to the material with low reflectance. 7 shows an organic EL element 70 having a light emitting layer 73 made of a polymer EL material, the method of using the low reflective metal is employed in any of the organic EL elements 60 · 70. can do.

In the present embodiment, however, nothing is particularly provided at the boundary between the organic EL element 60 and the liquid crystal layer 26, but the present invention is not necessarily limited thereto. For example, the organic EL element 70 described in Embodiment 2 described later will be described. It is also possible to provide the same light shielding layer as). When forming the light shielding layer in the organic electroluminescent element 60 of a present Example, what is necessary is just to form the organic electroluminescent element 60 in layer shape, and to apply a light shielding material to a wall surface.

Next, as shown in Figs. 8A and 8B, the counter substrate 52 and the TFT substrate 51 on which the organic EL elements 60 are formed are aligned with each other, bonded and fixed. Here, the organic EL element 60 is electrically connected to the TFT substrate 51 by the conductive contact layer 66, but is preferably conductive to both of the TFT substrate 51 and the counter substrate 52 in advance. It is preferable to form a resin and make electrical contacts to the conductive resins. This is because contact failure due to an oxide film or the like on the metal surface can be prevented, and a contact can be easily taken using the elasticity of the resin.

Thereafter, liquid crystal is injected. Injection can be performed by bonding the TFT substrate 51 and the counter substrate 52 and then vacuum injection.

Next, the material etc. of each member used for the organic EL element 60 are demonstrated.

First, the organic EL element 60 can use the color filter layer 28 used for the display on the liquid crystal display element 20 as it is, using the light emitting layer 63 which emits white light. In addition, it is not necessarily limited to this, It is also possible to use the light emitting layer 63 which emits any color among red (R), green (G), and blue (B). At this time, a part of the color filter layer 28 may be made transparent.

That is, in the light emission of the light emitting layer 63, the time deterioration of the light emission luminance is not the same depending on the colors of red (R), green (G), and blue (B). For this reason, when the light emitting layer 63 is used for a display element, color balance will fall with time. At this time, when the light emitting layer 63 which emits white light is used, such temporal color balance deterioration can be prevented. On the other hand, when the color filter layer 28 of each color is used while using the light emitting layer 63 which emits white light, since the transmittance | permeability becomes 1/3 by the color filter layer 28 of each color, light utilization efficiency is reduced. Done.

Therefore, in either case, the light emission color of each of red (R), green (G), and blue (B) is used in a display that is considered to have a relatively short period of use and a display where brightness is more important than an accurate color balance. It is preferable to use the light emitting layer 63. On the other hand, it is preferable to use the light emitting layer 63 which emits white light for applications, such as a television which requires the color balance performance for a long time.

Next, as a material which can be used as the light emitting layer 63 which consists of a low molecular type light emitting material which emits each color, for example, naphthalene, anthracene, phenanthrene, pyrene, tetracene, fluorescein, perylene, phthaloperylene, Naphthaloperylene, perinone, phthaloperinone, naphthaloperinone, diphenylbutadiene, tetraphenylbutadiene, coumarin, quinoline metal complex, imine, diphenylanthracene, diaminocarbazole, quinacridone, ruburan, etc. Can be mentioned.

On the other hand, as a material of the light emitting layer 63 which emits white light, those using a blue metal complex (Znbox2: zinc-benzoxazole 2) and a yellow metal complex (Znsq2: zinc-styrylquinoline 2) can be mentioned. The doped with fluorescent dye perylene or DCM1 (4- (dicyanomethylene) -2-methyl-6- (4-dimethylaminostyryl) -4H-pyran) can also be used. Further, PBD (2- (4-biphenylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole) was dispersed in a laminate of a polymer material or polyvinylcarbazole. A single layer material can also be used.

Examples of the material for the hole transport layer 64 include a phthalocyanine compound, a naphthalocyanine compound, porphyrins, oxadiazoles, triazoles, imidazoles, tetrahydroimidazoles, oxazoles, stilbenes, and the like.

In addition, examples of the material of the electron transport layer 62 include fluorenone, anthraquinodimethane, diphenylquinone, thiopyran dioxide, oxadiazole, thiadiazole, tetrazole, and perylenetetracarboxylic acid.

Examples of the electrode material of the cathode 61 include metals such as aluminum (Al), magnesium (Mg), and silver (Ag). Moreover, you may laminate | stack a metal material, such as nickel (Ni), titanium (Ti), tantalum (Ta), and gold (Au), and may improve contact property.

As the conductive resin of the conductive contact layer 66 for connecting the TFT substrate 51 and the counter substrate 52, for example, a photosensitive resin in which conductive particles described in Japanese Patent Application Laid-Open No. 99-249299 is dispersed (Fuji) The photosensitive conductive polymer using the polypyrrole as described in "Film Corporation" and "CHEMISTRY LETTERS, pp. 469-472,1986" of the magazine "1986 The Chemical Society of Japan" can be used. In detail, Japanese Patent Application Laid-Open No. 99-249299 discloses a technique relating to a photosensitive component product and a photosensitive sheet in which conductive particles such as carbon black are dispersed, and that a pattern can be formed by exposure and development. Is disclosed. In addition, "CHEMISTRY LETTERS, pp. 469-472, 1986" discloses photochemical polymerization of pyrrole monomers to give conductivity and formation of polypyrrole, and the use of patterning as an electrode material is also disclosed.

Next, the characteristics of the retardation plate 31 and the polarizing plate 32 formed on the counter substrate 52 will be described. These retardation plates 31 and polarizing plates 32 need to exclude a specific liquid crystal mode in order to form a reflective liquid crystal display device excluding a specific liquid crystal mode in the liquid crystal display element 20, and the phase difference in that case. The plate 31 is generally 1 / 4λ. In this embodiment, a metal such as aluminum (Al) is used for the cathode 61 of the organic EL element 60 in order to enhance the reflection effect. Therefore, when the organic EL element 60 does not emit light, the contrast decreases due to the light reflection by the cathode 61. Therefore, in order to prevent reflection, the polarizing plate 32 and the phase difference plate 31 of 1/4 (lambda) are needed on the display surface side of the organic electroluminescent element 60 normally. At this time, in the present embodiment, since the reflective liquid crystal display element 20 includes the polarizing plate 32 and the retardation plate 31 having the same configuration in advance, they can be shared without having to be newly provided.

Next, a driving circuit of the display device 50 having the above configuration will be described with reference to FIG. In this driving circuit, the signal lines and the scan signal lines are used for driving the liquid crystal display element 20 and the organic EL element 60 in order to actively drive each display pixel 10... As a display region formed in a matrix form. The gate bus line 3 ... and the source bus line 2a ... that is a signal line and a data signal line are shared. However, in the present invention, the present invention is not necessarily limited thereto, and may be applied to a simple matrix. In addition, the detailed description of the drive circuit is described in the seventh embodiment.

As shown in the figure, the circuit configuration of one pixel in the display device 50 is that the gate electrode of the liquid crystal TFT element 22 is connected to the gate bus line 3, and the source bus line 2a is connected. It is connected to the source electrode of the liquid crystal TFT element 22. The drain electrode 22a of the liquid crystal TFT element 22 is connected to the liquid crystal display element 20, the liquid crystal storage capacitor 35, and the gate electrode of the EL TFT element 42. The source electrode of the EL TFT element 42 is connected to the current supply line 2b, and the drain electrode of the EL TFT element 42 is connected to the cathode 61 of the organic EL element 60. In the above structure, the organic EL element 60 is provided on the drain side of the TFT element 42 for EL, but is not necessarily limited thereto. For example, as shown in FIG. 10, the EL TFT element 42 is shown. It may be provided on the source side of.

In the driving circuit of the display device 50 configured as described above, the liquid crystal TFT element 22 is turned ON / OFF by the scan line signal Vg input to the gate bus line 3..., The source bus line 2a. Data line signal Vs is input to the liquid crystal display element 20. The lighting state of the liquid crystal display element 20 is ensured by the liquid crystal storage capacitor 35. In the present embodiment, the EL threshold voltage Vth (OLED) of the EL TFT element 42 is set higher than the operating range voltage of the liquid crystal display element 20. That is, when the voltage of the data line signal Vs of the source bus line 2a ... exceeds the driving voltage range of the liquid crystal display element 20, the liquid crystal display element 20 is saturated, while the EL TFT element 42 Is turned on, and the organic EL element 60 emits light.

On the other hand, the liquid crystal display element 20 is normally set to white and becomes black in saturation. For this reason, in the voltage range in which the organic EL element 60 emits light, the liquid crystal display element 20 becomes the black matrix of the organic EL element 60, and the contrast decrease by the liquid crystal display element 20 does not occur.

In the voltage range in which only the liquid crystal display element 20 is operating, the light emitting region 12a does not emit light and becomes black due to the polarizing plate 32 and the retardation plate 31 provided on the panel display surface. Thereby, the contrast fall of the liquid crystal display element 20 by the organic electroluminescent element 60 does not occur.

Specifically, as shown in Fig. 11, when the data line signal Vs is less than the EL threshold voltage Vth (OLED) of the EL TFT element 42, the organic EL element 60 does not emit light and the liquid crystal display element 20 ) Reacts to dark display, i.e. black display. When the data line signal Vs is equal to or higher than the EL threshold voltage Vth (OLED) of the EL TFT element 42, the liquid crystal display element 20 performs dark display, but the EL TFT element is caused by the data line signal Vs. The drain current of (42) changes, and the light emission type of the organic EL element 60 is adjusted to perform light emission display. In addition, adjustment of the light emission amount of the organic EL element 60 can also be performed by adjusting supply voltage Vdd. The display device 50 of the present embodiment is not limited to this driving method and may be any other driving method. However, the driving method shown in Fig. 11 is suitable because the driving circuit is common.

On the other hand, different from the driving method described above, when the display of both the organic EL element 60 and the liquid crystal display element 20 is not integrated, the driving circuits can be provided so that independent driving is possible. It is preferable that the liquid crystal display element 20 at this time sets normally black so that the liquid crystal display element 20 may turn black in an OFF state. This is to increase display contrast without wasting power on the liquid crystal display device 20 when the liquid crystal display device 20 does not operate.

In addition, the conventional liquid crystal display device combining the transmissive liquid crystal display element and the reflective liquid crystal display element requires a light source for the transmissive display and a power source for the same, but the organic EL element 60 and the reflective liquid crystal display element 20 In the display device 50 of the present embodiment in which? Is inserted into the same panel, luminance modulation can also be performed by supplying power to the driver driver in advance.

Therefore, since the display device 50 of this embodiment does not require a power source for the light source, it is possible to reduce the cost, reduce the number of parts and reduce the size. In addition, in the case where the light emitting display element and the non-light emitting display element displayed by using external light are changed by the voltage applied to the signal wiring in common with the signal wiring, as shown in FIG. Corresponds to falling from point W to zero.

As described above, in the display device 50 of the present embodiment, in each display pixel 10.., The reflective region 11 made of a non-light emitting display element in which the liquid crystal display element 20 reflects external light and displays the light; And a light emitting region 12a composed of a light emitting display element in which the organic EL element 60 directly modulates and displays.

Therefore, since the liquid crystal display element 20 and the organic EL element 60 are arranged between the pair of insulating substrates 21 and 29, the thickness of the display device can be reduced.

Therefore, since the organic EL element 60 is directed toward the display surface and emits light by itself, the organic EL element 60 is not used as the backlight or the front light as in the related art. Therefore, this also increases the utilization efficiency of the light from the organic EL element 60 and at the same time reduces the thickness of the display device. That is, since the thickness of the backlight and the front light is usually about 3 to 6 millimeters, the advantage of the thickness reduction due to the need for the backlight is very large. In addition, the need for the backlight means that the polarizer, the retardation plate and the glass substrate on the back side, which are conventionally provided between the back panel and the backlight of the liquid crystal panel, also become unnecessary. Therefore, the thickness of the display device can be made thinner even when these polarizing plates, retardation plates, and glass substrates on the back side become unnecessary.

In addition, the advantage that the backlight, the polarizing plate and the retardation plate on the back side are not necessary is not merely the thickness of the entire display device. In other words, the reduction of the member scores can reduce not only the material cost but also the number of assembly steps and the cost required for inspection of each member, thereby lowering the manufacturing cost of the entire display device.

Therefore, the display device 50 excellent in visibility from the outdoors to the indoors can be provided while miniaturizing and reducing the cost.

In addition, in the display device 50 of this embodiment, the insulating substrate 21 and the insulating substrate 29 which face each other are provided, and the liquid crystal display element 20 and the organic EL element 60 are both insulating substrates. 21) and the insulating substrate 29 are provided. For this reason, since both the liquid crystal display element 20 and the organic electroluminescent element 60 are accommodated between the insulating board 21 and the insulating board 29, the thickness of the display device 50 can be reliably thinned. .

In the display device 50 of the present embodiment, the liquid crystal layer 26 of the liquid crystal display element 20 does not exist in the light emitting region 12a. That is, the liquid crystal layer 26 of the liquid crystal display element 20 does not exist on the display surface side of the light emitting layer 63 of the organic EL element 60. That is, it means that light emitted from the organic EL element 60 in the display surface direction does not pass through the liquid crystal layer 26 but exits the display device 50. The liquid crystal layer 26 does not exist on the display surface side of the light emitting layer 63. Except for the present embodiment, as shown in Example 3, for example, the end surface on the display surface side of the liquid crystal layer 26 is the light emitting layer ( Although it exists in the display surface side rather than the end surface of the display surface side of 63, the liquid crystal layer 26 of the display surface side of the light emitting layer 63, ie, the light emitting area 12a, is excluded by presence of an insulating layer, such as the insulating convex part 81, etc. There is a case. In addition, as a structure other than that, the form in which the light emitting layer 63 exists in the display surface side of the liquid crystal display element 20 is considered.

As a result, since the emitted light of the organic EL element 60 is not scattered or absorbed by the liquid crystal layer 26 of the liquid crystal display element 20, the luminance decrease hardly occurs. Therefore, the display quality by the organic EL element 60 can be improved.

In the display device 50 of the present embodiment, the liquid crystal layer 26 of the liquid crystal display element 20 and the light emitting layer 63 of the organic EL element 60 are provided in the same layer. The copper layer is not necessarily the same level, but includes a state in which the light emitting layer 63 of the organic EL element 60 is included in the liquid crystal layer 26 of the liquid crystal display element 20.

For this reason, the organic EL element 60 can be accommodated in the range of the thickness of the non-light emitting display element which consists of the conventional liquid crystal display element 20. As shown in FIG. As a result, the thickness of the display device 50 can be made sure.

In the display device 50 of the present embodiment, drive elements such as the liquid crystal TFT element 22 and the EL TFT element 42 which drive the organic EL element 60 and the liquid crystal display element 20 are one-sided. The organic EL element 60 is formed on the side of the TFT substrate 51 and on the side of the counter substrate 52 facing the TFT substrate 51.

For this reason, when manufacturing the display apparatus 50, drive elements, such as the organic electroluminescent element 60, the liquid crystal TFT element 22, and the EL TFT element 42, can be formed separately. Therefore, when forming the organic EL element 60, it is possible to avoid the influence of the process temperature, chemicals, gas, etc. at the time of forming the driving elements such as the liquid crystal TFT element 22 and the EL TFT element 42. Can be.

Further, since the light emitted from the organic EL element 60 is emitted to the counter substrate 52 side, the light is not blocked by the EL TFT element 42 driving the organic EL element 60, and light is effectively used. Can be. In addition, since the light emitting layer 63 can be formed from the transparent conductive layer which is the anode 65, the light emitting layer 63 can be formed with the same structure as before.

However, in the case where the organic EL element 60 is provided in the same layer as the liquid crystal layer 26 of the liquid crystal display element 20, the formation height of the organic EL element 60 and the liquid crystal layer 26 of the liquid crystal display element 20. Is not limited to the same thickness.

At this time, in the present embodiment, the TFT substrate 51 is provided with a conductive contact layer 66 for height adjustment, and an organic EL element 60 is formed on the conductive contact layer 66.

Therefore, the organic EL element 60 can be reliably provided in the same layer as the liquid crystal layer 26 of the liquid crystal display element 20.

In the display device 50 of this embodiment, the conductive contact layer 66 is made of a conductive resin. Therefore, by forming the conductive contact layer 66 made of the conductive resin from the TFT substrate 51, the height can be easily adjusted on the TFT substrate 51 side.

In the display device 50 of the present embodiment, a conductive material such as conductive paste or conductive resin is provided on the bonding surface between the cathode 61 of the organic EL element 60 and the TFT substrate 51 side.

In general, the conductive paste or the conductive resin is flexible, even when cured. Therefore, it is possible to ensure electrical bonding between the cathode 61 of the organic EL element 60 and the TFT substrate 51 side.

In the display device 50 of this embodiment, the organic EL element 60 and the liquid crystal display element 20 are driven by sharing the source bus line 2a ... and the gate bus line 3 ... .

For this reason, the display device which can prevent the structure of the drive circuit of the organic electroluminescent element 60 and the liquid crystal display element 20 from becoming complicated, and can surely reduce the thickness of a display apparatus, and can reduce the member cost ( 50).

In the display device 50 of the present embodiment, the organic EL element 60 and the liquid crystal display element 20 may be driven independently of each other. For this reason, it becomes possible to drive the organic electroluminescent element 60 and the liquid crystal display element 20 separately. Moreover, as a structure for driving the organic EL element 60 and the liquid crystal display element 20 independently from each other, for example, each of the organic EL element 60 and the liquid crystal display element 20 is a source bus line 2a ... ) And a gate bus line 3... Or a source bus line 2 a..., But may share a gate bus line 3.

In the display device 50 according to the present embodiment, the TFT substrate 42 for driving the organic EL element 60 and the liquid crystal display element 20 and the liquid crystal TFT element 22 is a TFT substrate. It is formed at 51. Therefore, by forming the EL TFT element 42 and the liquid crystal TFT element 22 on the TFT substrate 51, the manufacturing of the display device 50 can be made easier, and the configuration can be prevented from becoming complicated. Can be.

In the display device 50 of the present embodiment, the light modulation element is the reflective liquid crystal display element 20, and the light emitting element is the organic EL element 60.

Therefore, by using the reflective liquid crystal display element 20 as an optical modulation element, the liquid crystal display element 20 and the organic EL element 60 can be easily arranged in each display pixel 10...

In the display device 50 of the present embodiment, the counter electrode 27 of the liquid crystal display element 20 and the anode 65 of the organic EL element 60 are formed in the same layer by the same material. As a result, the manufacturing process can be shared, and the manufacturing process can be simplified.

In the manufacturing method of the display device 50 of the present embodiment, the liquid crystal TFT element 22 and the EL TFT element 42 are formed on the TFT substrate 51 as one substrate, and the counter substrate as the other substrate. After the organic EL element 60 is formed at 52, these TFT substrates 51 and the counter substrate 52 are joined together to integrate.

For this reason, when manufacturing the display apparatus 50, the organic electroluminescent element 60, the liquid crystal TFT element 22, and the EL TFT element 42 can be formed separately. Therefore, when forming the organic EL element 60, it is possible to prevent the influence of the process temperature, the chemicals, the gas, and the like when the liquid crystal TFT element 22 and the EL TFT element 42 are formed.

As a result, it is possible to provide a manufacturing method of the display device 50 excellent in visibility from outdoors to indoors while miniaturizing and reducing costs.

In the manufacturing method of the display device 50 of the present embodiment, the organic EL element 60 and the core portion 77 · 77 may be formed first. For this reason, it is possible to give priority to the process in which the formation of the organic electroluminescent element 60 and the core part 77 * 77 can be easily formed in any one.

In the display device 50 of the present embodiment, after the conductive paste or the conductive resin is provided on the bonding surface between the cathode 61 of the organic EL element 60 and the TFT substrate 51 side, the TFT substrate 51 is provided. ) And the opposing substrate 52 may be bonded to each other.

Therefore, the contact surface between the cathode 61 of the organic EL element 60 and the TFT substrate 51 side is made of resins or resins and pastes to improve contact performance by elasticity of the resins and pastes. Can be planned.

(Example 2)

Another embodiment of the present invention will be described below with reference to FIGS. 12 to 15. In addition, for the convenience of description, the same code | symbol is attached | subjected about the member which has the same function as the member shown by the drawing of the said Example 1, and the description is abbreviate | omitted.

In this embodiment, a case of forming an organic EL element with a polymer type EL material will be described.

In the organic EL element 70 of this embodiment, as shown in Fig. 12, the light emitting layer 73 is made of a polymer type EL material, and the cathode 61 and the anode 65 are directly above and below the light emitting layer 73. Is joined. That is, in the organic EL element 70 of the present embodiment, the hole transport layer 64 and the electron transport layer 62 existing in the organic EL element 60 of the first embodiment are omitted. However, also in this embodiment, it is possible to provide these hole transport layers 64 and electron transport layers 62.

  In this embodiment, the core portions 77 · 77 are formed on both sides of the light emitting layer 73 as protective layers for insulating the liquid crystal layer 26. When forming the light emitting layer 73, the core portion 77 · 77 can be formed first, and the light emitting layer 73 can be formed by inkjet coating or printing the EL material therein.

The core portion 77 · 77 can be made of a material called a resist or polyimide. The core portion 77 · 77 is preferably a light shielding material. This is because light leakage in the lateral direction of light emitted from the light emitting layer 73 enters the liquid crystal layer 26 and becomes stray light, resulting in a decrease in contrast.

The manufacturing method of the said organic electroluminescent element 70 is demonstrated.

First, as shown in FIG. 13A, core portions 77 占 are formed on the counter electrode 27 and the anode 65 side of the counter substrate 52. As shown in FIG. It is formed by a photolithography process or an ink jet coating method using a resist or polyimide.

Then, as shown in Fig. 13B, a light emitting layer 73 made of a polymer EL material is formed in this portion by, for example, an ink jet coating method. Examples of the polymer EL material include polyphenylene vinylene, polyfluorene, polythiophene, polyvinylcarbazole and the like.

Finally, as shown in Fig. 13C, for example, a conductive polymer material may be applied thereon to form the cathode 61. In addition, after forming a metal material such as aluminum (AL), magnesium (Mg), aluminum (AL) -magnesium (Mg) alloy, and a metal paste, a conductive polymer material may be applied to form the cathode 61. good.

On the other hand, as shown in Fig. 14, the TFT substrate 51 side has a photosensitive conductive resin on the TFT substrate 51 on which the liquid crystal TFT element 22, the EL TFT element 42 and the pixel electrode 25 are formed. The conductive contact layer 66 can be formed by applying the jet coating method.

Subsequently, as shown in Figs. 5A and 15B, the counter substrate 52 on which the organic EL element 70 is formed and the TFT substrate 51 are matched with each other and adhesively fixed in the same manner as in the first embodiment.

Thereafter, the liquid crystal is injected and sealed. At this time, when the formed core portion 77 · 77 is formed over the display panel width in the scanning line direction, vacuum injection can be performed from the end of the display panel along the scanning line.

In addition, since the other structure, the drive operation | movement, the display method, etc. of this organic EL element 70 are the same as that of Example 1, the description is abbreviate | omitted.

As described above, in the organic EL element 70 of the present embodiment, at least the light emitting layer 73 and the cathode 61 and the anode 65 formed on both sides of the light emitting layer 73 are formed.

For this reason, when forming the light emitting layer 73 which consists of polymeric EL materials, for example, the organic electroluminescent element 70 can be formed from the minimum components.

By the way, in the display device 50, since the organic EL element 70 is disposed on the same layer as the liquid crystal layer 26 of the liquid crystal display element 20, the liquid crystal layer 26 of the liquid crystal display element 20 There is a fear that the organic EL elements 60 influence each other. For example, when the organic EL element 70 is in contact with the liquid crystal layer 26 such as liquid crystal of the liquid crystal display element 20 and the organic EL element 70, the performance of both may be degraded or the material may be degraded. . In addition, the organic EL element 70 may deteriorate due to contact with air or moisture.

However, in the present embodiment, the light emitting layer 73 of the organic EL element 70 and the liquid crystal layer 26 of the liquid crystal display element 20 are adjacent via the core portions 77 · 77.

Therefore, it is possible to prevent the light emitting layer 73 of the organic EL element 70 and the liquid crystal layer 26 of the liquid crystal display element 20 from affecting each other. That is, after arrange | positioning the organic electroluminescent element 70 to the same layer as the liquid crystal layer 26 of the liquid crystal display element 20, performance of both can be prevented or material deterioration can be prevented. In the manufacturing process of the display device 50, for example, when the organic EL element 70 is formed on the opposite substrate 52 side, the light emitting layer 73 serves as the core portion 77 · 77 and the cathode 61. By protecting, the light emitting layer 73 can be prevented from deteriorating in contact with air or moisture.

By the way, it is also conceivable that the light emitted by the organic EL element 70 leaks to the adjacent liquid crystal display element 20.

In this regard, in the display device 50 of the present embodiment, since the core portions 77 and 77 have a light shielding function, the light emitted by the organic EL element 70 is emitted from the liquid crystal layer 26 of the liquid crystal display element 20. To prevent leakage.

(Example 3)

Another embodiment of the present invention will be described with reference to FIGS. 16 to 19 as follows. In addition, for the convenience of description, the same code | symbol is attached | subjected about the member which has the same function as the member shown in the drawing of the said Example 1 and Example 2, and the description is abbreviate | omitted.

In the display device 50 of this embodiment, as shown in FIG. 16, an insulating iron portion 81 as a hard and transparent iron portion is disposed on the side of the opposing substrate 52, and the organic EL element 70 is TFT. It is arrange | positioned at the board | substrate 51 side. The said insulating convex part 81 is used as the thickness control pillar of the liquid crystal layer 26. As shown in FIG.

That is, the thickness of the liquid crystal layer 26 is usually set to 3 to 5 mu m. On the other hand, the thickness of the organic EL element 70 is about 0.1 to 0.5 µm. In the organic EL device 60 and the organic EL device 70 shown in Figs. 1 and 12 shown in the first and second embodiments, the difference in thickness is adjusted by the conductive contact layer 66, which is a connection resin. .

In contrast, in the present embodiment, the insulating convex portion 81 having a height in consideration of the thickness difference between the liquid crystal layer 26 and the organic EL element 70 is provided in advance. In addition, although the connection part is not specified in FIG. 16, a connection part exists.

It is necessary to use a high transmittance resin material as a material for forming the insulating iron portions 81. For example, the photosensitive spacer material and product name "Optomer NN series" by JSR Corporation can be used. This high transmittance resin material has a higher hardness after formation than the connection resin used in the conductive contact layer 66 and the connecting portion. Because of this property, the effect of keeping the distance between the counter substrate 52 and the TFT substrate 51 constant by setting the height can be expected.

Conventionally, the thickness of the liquid crystal layer 26 is controlled by the spacer beads scattered on the liquid crystal layer 26, but since the liquid crystal layer 26 is on the pixel display surface of the liquid crystal layer 26, the image quality is reduced by causing contrast reduction or scattering. have. In addition, sufficient thickness control was not performed even by the spacer beads.

However, as in this embodiment, by controlling the thickness of the liquid crystal layer 26 by the insulating convex portion 81, the thickness control accuracy of the liquid crystal layer 26 can be improved and the strength of the panel can be expected to be improved. Will be.

In addition, in this embodiment, although the insulating convex part 81 is used only for the said thickness control, it is not necessarily limited to this, The insulating convex part 81 is a light control member from the organic electroluminescent element 70, In other words, an organic electroluminescent element. It is also possible to use it as an optical element for controlling the light from 70. For this purpose, for example, as shown in Fig. 7, an insulating convex portion 82 composed of tooth-shaped convex portions 82a and 82b as convex portions having a plurality of transparent resins having different refractive indices in the form of a tooth may be used. have. By having such a structure, it becomes possible to give directivity to the light emitted from the organic EL element 70. In addition, since the directivity characteristic can be changed by changing the shape of the tooth, the same viewing angle characteristic as that of the liquid crystal display device can be obtained.

Here, when the organic EL element 70 of the present embodiment is viewed from the display surface, as shown in Fig. 18, the ranges determined by W and L correspond to one display pixel 10... (11) and the light emitting area 12a are divided. As shown in the above figure, the pixel electrode 25 and the liquid crystal TFT element 22 or the EL TFT element 42 are connected to each of the reflective region 11 and the light emitting region 12a. The through hole 25a is formed.

In addition, the divisional arrangement | positioning of the reflective area | region 1 and the light emitting area | region 12a in said display pixel 10 ... is not necessarily limited to this. For example, as shown in FIG. 19A, the reflective region 11 is shaped like a shape in which the light emitting region 12a by the organic EL element 70 is surrounded by the reflective region 11 by the liquid crystal display element 20. One of the light emitting regions 12a may be surrounded by the other. In the shape where the light emitting region 12a by the organic EL element 70 shown in the same figure is surrounded by the reflecting region 11 by the liquid crystal display element 20, the organic EL element 70 emits light when the organic EL element 70 emits light. When the reflective regions 11 of the liquid crystal display element 20 are all black, the adjacent display elements act as a black matrix, which is effective in increasing the contrast compared to the shape shown in FIG.

Further, even in the shape as shown in Fig. 19B, if the display pixel 10 is laid on the entire surface, the light emitting region 12a by the organic EL element 80 is the reflecting region by the liquid crystal display element 20. Since it is surrounded by (11), the same effect can be expected.

The area of the light emitting area 12a and the reflecting area 11 can be determined according to the use of the display device.

In addition, in the present embodiment, the organic EL element 70 of the light emitting layer 73 made of a polymer type EL material has been described. However, the present invention is not necessarily limited thereto, and the organic EL of the light emitting layer 63 made of a low molecular type EL material is described. This embodiment can also be applied to the device 60.

In addition, about other structure, since it is the same as that of Example 1-Example 2, the description is abbreviate | omitted.

  As described above, in the display device 50 of the present embodiment, the opposing substrate 52 is provided with an insulating convex portion 81 or an insulating convex portion 82 for adjusting the formation height, and the insulating convex portion 81 or the insulating concave portion 82 is provided. The organic EL element 70 is formed on ().

Therefore, when the organic EL element 70 is provided on the same layer as the liquid crystal layer 26 of the liquid crystal display element 20, the height of the organic EL element 70 and the liquid crystal layer 26 of the liquid crystal display element 20 are provided. The organic EL elements 70 can be reliably provided on the same layer as the liquid crystal layer 26 of the liquid crystal display element 20 even if the thicknesses of do not match.

In the display device 50 of this embodiment, the insulating convex portion 81 or the insulating convex portion 82 is formed of a hard insulating layer. Therefore, the height can be easily adjusted from the counter substrate 52 side by forming the insulated iron portions 81 or the insulated iron portions 82 formed of the hard insulation layer from the counter substrate 52 side. In addition, by forming the insulating convex portion 81 or the insulating convex portion 82 as a hard insulating layer, the insulating convex portion 81 or the insulating concave portion 82 can be functioned as a spacer for keeping the interval of the liquid crystal layer 26 of the liquid crystal display element 20 constant.

In addition, in this embodiment, the insulating convex portions 82 made of a hard insulating layer can be formed in two layers, and the interface can be formed into a sawtooth shape to form the saw tooth concave portions 82a and 82b. Thereby, directivity can be made with respect to the light emitted from the organic EL element 60. In this manner, the insulating convex portion 82 can also function as a light control member of the organic EL element 60.

In addition, in the pixel dividing display device 50 of the present embodiment, the ratio of the reflecting region 11 and the emitting region 12a can be arbitrarily designed to some extent. For this reason, it is common to make the ratio of the reflection area 11 which is a reflection area large when it is assumed to be used for mobile devices, such as a cellular phone and an information portable terminal (PDA), for example. For example, when 80% of the pixel area of the display pixel 10 is a reflection area, the light emitting area 12a becomes 20%. Therefore, the light emitting area of the organic EL element 60 is at most 5 minutes of the pixel area. Only one.

Therefore, it is possible to provide a display device with excellent visibility from outdoors to indoors, while miniaturizing and reducing costs.

In addition, in the display device 50 of this embodiment, when the liquid crystal display element 20 is in a bright display state, the organic EL element 70 can select a non-light emitting state. For this reason, when using in a bright environment, the organic electroluminescent element 70 is made into the no light emission state, and display is performed only by the liquid crystal display element 20, and deterioration of the organic electroluminescent element 70 is prevented and a lifetime is extended. And it can save power consumption.

In the display device 50 of this embodiment, the liquid crystal display element 20 and the organic EL element 70 are arranged in an adjacent state, and either of the liquid crystal display element 20 and the organic EL element 70 When in the light display state, the other side is in the dark display state.

Thereby, one side becomes the black matrix 33, and it does not reduce display contrast.

(Example 4)

Another embodiment of the present invention will be described below with reference to FIG. In addition, for the convenience of description, the same code | symbol is attached | subjected about the member which has the same function as the member shown in the drawing of said Example 1-Example 3, and the description is abbreviate | omitted. In addition, the various feature points described in the first to third embodiments can also be applied to the present embodiment.

In the present embodiment, the case where external light is detected by the optical sensor and the luminance of the organic EL element 60 or the organic EL element 70 is adjusted based on the detection result will be described.

That is, as shown in FIG. 20, in the display device 50, a control circuit 91 and a power supply circuit 92 as display control means are arranged, and the control circuit 91 receives an image display signal and supplies a power supply unit. In addition to generating a signal to the source driver 6 through 90, the signal is also generated to the gate driver 7. In this embodiment, an optical sensor 93 as external light detecting means is connected to the control circuit 91 via the measuring circuit 23.

The control circuit 91 controls the optical sensor 93 and controls external light measurement. The optical sensor 93 is composed of, for example, a phototransistor.

In this embodiment, since the organic EL element 60 or the organic EL element 70 is used as the light emitting element and the liquid crystal display element 20 is used as the light modulation element, the power supply unit 90 is a liquid crystal. It is a constant current or constant voltage power supply for driving the organic EL element 60 or the organic EL element 70, which requires driving capability rather than driving. Therefore, the power supply unit 90 is not used only for the liquid crystal display.

The control by the optical sensor 93 and the control of external light measurement will be described.

First, in a dark environment, the control circuit 91 recognizes that the surroundings are dark by the signal from the optical sensor 93, and thus the data line signal and gate line for driving the organic EL element 60 or the organic EL element 70. Generate a signal. At this time, when the gray scale representation of the organic EL element 60 or the organic EL element 70 is performed on the power supply unit 90 side, a signal is supplied from the control circuit 91 to the power supply unit 90.

On the other hand, in the bright environment, a data line signal and a gate line signal for driving the reflective liquid crystal display element 20 are generated based on the signal from the optical sensor 93. In this case, as described above, since the power supply unit 90 does not matter, a signal for directly controlling the power supply from the control circuit 91 is not necessarily required.

When both the organic EL element 60 or the organic EL element 70 and the liquid crystal display element 20 are displayed at the same time, the control signal 91 sends a source signal for each display. As a result, luminance can be adjusted for each display, so that an appropriate display state can be selected according to the surrounding environment.

In this manner, by measuring the external light by the optical sensor 93, the organic EL element 60 or the organic EL element 70 is automatically emitted, or the reflective display of the liquid crystal display element 20 may be performed. Not only can it be switched, but it is also possible to select a display state appropriate for the environment.

As described above, in the display device 50 of the present embodiment, the organic EL element 60 or the organic EL element 70 and the liquid crystal are based on the detection result of the external light by the optical sensor 93 by the control circuit 91. Both or either of the display elements 20 is selectively displayed.

Therefore, the display of the organic EL element 60, the organic EL element 70, or the liquid crystal display element 20 can be selected automatically in response to the ambient light, thereby ensuring an appropriate display state.

(Example 5)

Another embodiment of the present invention will be described below with reference to FIGS. 21 to 26. In addition, for the convenience of description, the same code | symbol is attached | subjected about the member which has the same function as the member shown in the drawing of said Example 1-Example 4, and the description is abbreviate | omitted. The various feature points described in the first to fourth embodiments can also be applied to the present embodiment.

As shown in Fig. 21, the display device 1 of this embodiment has a source bus line 2a as a data signal line provided in a plural number in the longitudinal direction and a gate bus line as a scan signal line in a plural direction in the lateral direction. By this, each display pixel 10... As a display area is formed in a matrix form.

In the present embodiment, the display pixel 10 is divided into a reflective region 11 which is a reflective first display region and a transmissive region 12 which is a second transparent display region. That is, as shown in FIG. 22, a pixel electrode 25 made of metal such as aluminum (Al) constituting the reflective liquid crystal display device 20, which is an optical modulation element, is formed in the reflective region 11. In this way, the external light 4 is reflected by the pixel electrode 25.

On the other hand, as shown in the same figure, the rectangular opening 25a is formed in the center part of the pixel electrode 25, and this opening 25a becomes the said transmission area | region 12. As shown in FIG. Below the opening 25a of the pixel electrode 25, that is, behind the pixel electrode 25, the organic EL element 40 which is a light emitting element is arrange | positioned through the transparent insulating layer 24, and this organic EL element is arrange | positioned. 40 directly displays by emitting the display light 5 by itself. That is, in the present embodiment, since the organic EL element 40 directly displays the organic EL element as the backlight or the front light as in the prior art, the display device 1 of the present embodiment uses the liquid crystal display element 20. It can be said that the reflection type liquid crystal display device constituted by () and the organic EL display device constituted by the organic EL element 40 are integrated displays.

Here, the organic EL element 40 can have an area substantially equal to or smaller than the area of the transmission region 12. That is, the organic EL element 40 does not necessarily need to be formed in the entire transmission region 12, but may be formed in the required area according to the required screen brightness. For this reason, the power consumption of the organic EL element 40 can be reduced by making the area of the organic EL element 40 smaller than the transmission region 12. In addition, that the organic EL element 40 is substantially the same as the area of the transmissive region 12 means that the organic EL element 40 may be slightly larger than the area of the transmissive region 12. That is, if the organic EL element 40 is only slightly larger than the area of the transmission region 12, it is considered that the irradiation efficiency of the organic EL element 40 is not impaired. In addition, even if the organic EL element 40 is slightly larger than the area of the transmissive region 12, the pixel electrode 25 acts as a black matrix, so this is not a problem.

The display device 1 has a liquid crystal TFT element 22 on an insulating substrate 21 which is a first substrate such as a glass substrate as shown in the same drawing. This liquid crystal TFT element 22 is connected to the gate bus line 3... And the source bus line 2a .. as shown in FIG. 21, and the pixel electrode 22 is connected through the drain electrode 22a. It acts as a switching element for applying a voltage to 25).

On the other hand, the drain electrode 22a of the liquid crystal display element 20 is connected to the gate electrode of the EL TFT element 42 for driving the organic EL element 40 as shown in the same figure. In addition, the current supply line 2b is connected to the source side of the EL TFT element 42, and the EL TFT element 42 is turned ON so that the current supply line V is supplied by the supply voltage Vdd described later. 2b) and a driving current flows into the organic EL layer 41 of the organic EL element 40 through the drain electrode of the EL element 42 for EL, and the organic EL layer 41 emits light. The organic EL layer 41 is composed of an electron transport layer 62, a light emitting layer 63, and a hole transport layer 64 in the organic EL device 60 having the light emitting layer 63 of the low molecular type EL material. In the organic EL element 70 having the light emitting layer 73 of the polymer type EL material, only the light emitting layer 73 is formed.

Here, in order to explain the structure of the display device 1 in more detail, the following description will be given with reference to Figs.

First, as shown in Fig. 21, a liquid crystal TFT element 22 is formed on an insulating substrate 21 such as a glass substrate. At this time, the EL TFT element 42 is also formed at the same time. Subsequently, the planarization film 23 is formed to have a thickness of, for example, 2 μm by photosensitive acrylic resin, and then the reflective anode 43 constituting the organic EL element 40 is formed to be 2000 mm thick with chromium by the sputtering method. Subsequently, silicon dioxide (SiO ₂ ) is formed to a thickness of 2000 GPa by the sputtering method, and the insulating layer 44 is formed by etching to form a predetermined shape.

Then, the organic EL layer 41 which is a light emitting layer is formed by vapor deposition. The organic EL layer 41 is formed by mask evaporation so as to correspond to the display pixels 10..., Red, green, and blue light emitting materials. Subsequently, in order to efficiently inject electrons into the organic EL layer 41, an unillustrated alloy of magnesium and silver was formed to a thickness of 100 kPa by evaporation, and then indium-zinc by sputtering as a cathode 45 having transparency. Oxide (IZO) is formed to a thickness of 2000 kPa. Subsequently, after forming the tantalum pentoxide (Ta ₂ O ₅ ) as the transparent insulating layer 24 to a thickness of 7000 kPa by the sputtering method, the reflectivity for driving the liquid crystal layer 26 constituting the liquid crystal display element 20 is shown. The pixel electrode 25 having is formed of aluminum (Al).

On the other hand, on the insulating substrate 29 as a transparent second substrate such as the other glass substrate, a counter electrode 27 made of a color filter layer 28 and an indium tin oxide (ITO) is sequentially formed.

Next, an unillustrated alignment film (trade name "JALS204 (manufactured by Japan Synthetic Rubber Co., Ltd.)) having the property of orienting the liquid crystal molecules perpendicularly to the insulating substrate 29 is applied by spin coating and then fired.

Subsequently, ultraviolet light is irradiated to the molded substrate on the side of the insulating substrate 21 through a mask (not shown) in which openings are formed so as to expose only to regions other than the portions where the organic EL elements 40 are formed. On the other hand, also when the molded substrate on the insulating substrate 29 side is bonded to the insulating substrate 21, ultraviolet light is irradiated to a region other than the portion facing the organic EL element 40. By rubbing these two molded substrates, a uniaxial orientation treatment is performed on an oriented film (not shown), and bonded through a sealing resin, followed by injecting a liquid crystal material (manufactured by Merck) having a positive dielectric anisotropy and? N of 0.06. The liquid crystal display device 20 is manufactured. In addition, the display device 1 is completed by sequentially bonding the retardation plate 31 and the polarizing plate 32 to the surface of the insulating substrate 29. In addition, the phase difference of the retardation plate 31 used was made into 1/4 with respect to the light of (lambda) = 550 nm.

When the display device 1 fabricated in this way is observed with no voltage applied under the external light 4, the portion located above the organic EL element 40 is black and the portion not forming the organic EL element 40 It is white. This is because the liquid crystal molecules were aligned in parallel with the insulating substrate 21 and the insulating substrate 29 by cutting off the functional group expressing the vertical alignment of the alignment film.

As a result, the display mode of the liquid crystal layer 26 displays white in a voltage-free state, and the reflectance gradually decreases due to application of voltage to the normally white mode of black display. Next, an example of a drive circuit for driving the display device 1 having the above configuration will be described.

As shown in Fig. 23, in the display device 1, a source driver 6 for sequentially transmitting data line signals is connected to a source bus line 2a. The gate driver 7 for selecting is connected to the gate bus line 3... In addition, the display circuit in one display pixel 10 is comprised by the liquid crystal display element 20 which is an optical modulation element, and the organic electroluminescent element 40 which is a light emitting element.

These liquid crystal display elements 20 and organic EL elements 40 are arranged in a matrix form in the display area of the display device 1, respectively, and the counter electrode 27 of the liquid crystal display element 20 and the TFT for EL element ( The current supply line 2b of 42 and the cathode 45 of the organic EL element 40 are commonly connected to each of the liquid crystal display element 20 and the organic EL element 40, respectively. That is, in this driving circuit, the driving of the liquid crystal display element 20 and the organic EL element 40 in order to actively drive each display pixel 10... As a display area formed in a matrix form is a signal line and a scanning signal line. The gate bus line 3 ... and the source bus line 2a ... that is a signal line and a data signal line are shared. However, in the present invention, the present invention is not necessarily limited thereto and may be applied to a simple matrix.

As a result, when driving this display device 1, the driving method shown in Figs. 9, 10 and 11 shown in the first embodiment is applied. The detailed description of the driving method is omitted as described above.

The display operation will be described in detail with reference to Figs. 24 to 26 show the state of light in the case where the birefringence of the liquid crystal layer 26 without the voltage of the liquid crystal layer 26, which is the condition that the reflectance is highest, is? / 4.

First, when the display device 1 is used under the external light 4, when the data line signal Vs is no voltage or the drain voltage Vd of the liquid crystal TFT element 22 is the liquid crystal threshold voltage Vth. If it is less than (LC), as shown in FIG. 24, the external light 4 exceeds the polarizing plate 32 and the retardation plate 31, becomes circularly polarized light, and enters into the liquid crystal layer 26. As shown in FIG. Subsequently, since the liquid crystal layer 26 has a phase difference of? / 4, when it reaches the reflective pixel electrode 25, it becomes a phase difference of? / 2 and reflects as linearly polarized light. After the reflection, the external light 4 becomes linearly polarized light through a path opposite to that at the time of incidence, and thus passes through the polarizing plate 32 to become white display. At this time, since the drain voltage Vd of the liquid crystal TFT element 22 is less than the EL threshold voltage Vth (OLED) at which the EL TFT element 42 operates, no current is supplied to the organic EL element 40. Become non-luminous.

Subsequently, in the case of using the display device 1 under the external light 4, the threshold voltage Vth (LC) for the liquid crystal is greater than that in the case where the drain voltage Vd of the liquid crystal TFT element 22 is applied. Black display of the liquid crystal display element 20 will be described.

As shown in FIG. 25, since the birefringence of the liquid crystal layer 26 is approximately 0, the external light 4 maintains, for example, a circularly polarized state of right circularly polarized light when it reaches the reflective pixel electrode 25. At the time of reflection, it becomes circularly polarized light of reverse rotation of left circularly polarized light, for example. For this reason, after the reflected light of the external light 4 exceeds the retardation plate 31, it becomes linearly polarized light of the angle which is orthogonal to the transmission axis of the polarizing plate 32 by 90 degrees. For this reason, the reflected light of the external light 4 cannot pass through the polarizing plate 32, and the display becomes black.

At this time, since the drain voltage Vd of the liquid crystal TFT element 22 is less than the EL threshold voltage Vth (OLED) at which the EL TFT element 42 operates, a current is applied to the organic EL element 40. Is not supplied and remains unlit.

Next, the case where the organic EL element 40 emits light when the intensity of the external light 4 is weak will be described.

In this case, as shown in Fig. 26, the drain voltage Vd of the liquid crystal TFT element 22 is equal to or higher than the EL threshold voltage Vth (OLED) at which the EL TFT element 42 operates. As a result, a current is supplied to the organic EL element 40 to emit light. At this time, as shown in FIG. 11, since the drain voltage Vd is sufficiently high and the liquid crystal layer 26 has black display, it does not affect the light emission of the organic EL element 40. FIG.

Here, in the present embodiment, the anode 43 constituting the organic EL element 40 is made of a reflective metal, and always reflects light regardless of the display signal. In the case where the organic EL display is mounted on a product having many opportunities for outdoor use such as a mobile phone, it is necessary to attach a circular polarizing plate to the observer side. In this embodiment, as shown in Fig. 26, the liquid crystal layer 26 The retardation plate 31 having a phase difference of? / 4 wavelength with the polarizing plate 32 required for display has a function of making the reflection of the external light 4 almost zero. In addition, although the liquid crystal layer 26 exists between the organic EL element 40 and the polarizing plate 32, the liquid crystal layer 26 of this portion is formed of an electrode such as the counter electrode 27 except for the insulating substrate 29 side. It is not. For this reason, the liquid crystal layer 26 is always in the OFF state regardless of the applied voltage, and does not adversely affect the reflection suppression of the external light 4.

In this embodiment, since the transparent insulating layer 24 is formed so as to cover the entire surface of the organic EL element 40, since the liquid crystal of the liquid crystal layer 26 does not penetrate the organic EL element 40, It is also possible to improve the reliability of the organic EL element 40.

As described above, in the display device 1 of the present embodiment, in each display pixel 10..., The reflection area including the non-light emitting display element in which the liquid crystal display element 20 reflects the external light 4 and displays the light ( 11) and a transmissive region 12 made of a light emitting display element which directly modulates and displays the organic EL element 40.

Therefore, similarly to the display device 50 shown in the first to fourth embodiments, the light utilization efficiency of the organic EL element 40 can be increased and the thickness of the display device can be made thin.

In addition, since the backlight, the polarizing plate and the retardation plate on the back side become unnecessary, the member score is reduced. As a result, not only the material cost but also the cost required for the number of assembly steps, inspection of each member, and the like can be reduced, thereby reducing the manufacturing cost of the entire display device.

In addition, in the pixel division display device 1 as in the present embodiment, it is possible to arbitrarily design the ratio of the reflection area 11 and the transmission area 12 to some extent. For this reason, power consumption can be reduced.

In this embodiment, the insulating substrate 21 and the insulating substrate 29 which face each other are provided, and the organic EL element 40 and the liquid crystal display element 20 are both the insulating substrate 21 and the insulating substrate ( 29) is arranged between. The organic EL element 40 and the liquid crystal layer 26 of the liquid crystal display element 20 are sequentially stacked on the insulating substrate 21 in the transmission region 12. For this reason, since both the liquid crystal display element 20 and the organic electroluminescent element 40 are accommodated between the insulating board 21 and the insulating board 29, the thickness of the display apparatus 1 can be reliably thinned. . In addition, even if the liquid crystal layer 26 is laminated on the surface side of the organic EL element 40, the organic EL element 40 is provided between the insulating substrate 21 and the insulating substrate 29, and therefore, the organic EL element. All of the display light at 40 is emitted to the transmission region 12. For this reason, the utilization efficiency of light becomes very high.

Therefore, it is possible to provide a display device 1 having excellent visibility from outdoors to indoors, while miniaturizing and reducing costs.

By the way, the organic EL element 40 does not necessarily need to be formed in the whole transmission region 12, but may be formed in the required area according to the screen brightness required. In this regard, in the display device 1 of this embodiment, the organic EL element 40 has an area substantially equal to or smaller than that of the transmission region 12. Therefore, the power consumption can be further reduced with respect to the organic EL element 40.

In the display device 1 of this embodiment, the light emitting element is made of the organic EL element 40. Therefore, the liquid crystal display element 20 and the organic EL element 40 can be easily embedded between the pair of insulating substrates 21 and 29.

In addition, since the power consumption of the light emitting element is proportional to the light emitting area by using the current-driven organic EL element 40 as the light emitting element, the power consumption of the display device 1 of the present embodiment is the organic EL element 40. Power consumption is 1/5 compared with the case of using. Therefore, it is possible to surely reduce the power consumption.

Incidentally, in the display device 1 of the present embodiment, the optical modulator is a liquid crystal display element 20. Therefore, when the liquid crystal display element 20 and the organic EL element 40 are easily formed in one pixel, the light is incident to the opening portion 25a with higher irradiation efficiency, thereby miniaturizing and reducing the cost. It is possible to provide the display device 1 excellent in visibility from the indoor to indoors.

In the display device 1 of this embodiment, the organic EL element 40 and the liquid crystal display element 20 are driven by sharing the source bus line 2a ... and the gate bus line 3 .... For this reason, the display circuit which prevents the structure of the drive circuit of the organic electroluminescent element 40 and the liquid crystal display element 20 from becoming complicated, and can surely reduce the thickness of the display apparatus 1 and the member cost can be aimed at. The device 1 can be provided.

However, in the present embodiment, when the organic EL element 40 emits light, for example, when white display is performed, when the liquid crystal display element 20 performs white display, the contrast of one display pixel 10 is lowered. do.

Thus, in the present embodiment, the liquid crystal layer 26 of the liquid crystal display element 20 is in the horizontal alignment mode in the reflective region 11 and in the vertical alignment mode in the transmissive region 12. Therefore, in the state where no voltage is applied to the liquid crystal display device 20, the reflection area 11 is white display, while when the voltage is applied to the liquid crystal display device 20, the reflectance becomes 0 and the reflection area 11 ) Becomes a black display.

Therefore, in the present embodiment, since the periphery of the transmission region 12, which is the display region of the organic EL element 40, becomes black display, it is possible to prevent the lowering of the contrast caused by driving the organic EL element 40 by light emission. .

Further, when the transmissive region 12 in which the organic EL element 40 displays in the liquid crystal layer 26 of the liquid crystal display element 20 is horizontally aligned, the pixel electrode for driving the liquid crystal display element 20 ( Since 25) is not formed, the parallel orientation of the initial orientation is maintained. Therefore, especially when the display device 1 is used in a place with a lot of external light 4 such as outdoors, the reflected light by the external light 4 increases in the transmissive region 12 which maintains the horizontal alignment. In other words, the external light 4 passes through the liquid crystal display element 20 and is reflected by the organic EL element 40.

In this respect, in this embodiment, the alignment of the liquid crystal layer 26 stacked on the organic EL element 40 is vertically aligned, and the alignment of the liquid crystal layer 26 of the reflective region 11 is horizontally aligned. Therefore, when only the organic EL element 40 emits light without driving the liquid crystal display element 20, the contrast and the display quality of the contrast due to the overlap of the reflected light of the external light 4 in the transmission region 12 The bad influence can be prevented.

In addition, in the present embodiment, the color filter layer 28 formed on the insulating substrate 29 is formed in all portions facing the reflective region 11 and the transparent region 12, but is not necessarily limited thereto. It is not necessary to form the color filter layer 28 in the part which opposes (12), in other words, the area | region which opposes the organic electroluminescent element 40. FIG. As a result, light emitted from the organic EL layer 41 is not absorbed by the color filter layer 28, so that brighter display is possible. In addition, since the color purity of the organic EL layer 41 is usually superior to the color purity of the color filter layer 28, a clearer display is possible.

In addition, in the present embodiment, the display device in which the liquid crystal display element 20 and the organic EL element 40 are combined has been described. However, the present invention is not necessarily limited thereto, and the organic EL element 40 may include the aforementioned organic EL element ( 60, 70, 80).

(Example 6)

Another embodiment of the present invention will be described below with reference to Figs. In addition, for the convenience of description, the same code | symbol is attached | subjected about the member which has the same function as the member shown in the drawing of said Example 1-Example 5, and the description is abbreviate | omitted. The various feature points shown in the first to fifth embodiments can also be applied to the present embodiment.

In this embodiment, the case where the liquid crystal display element 20 and the organic EL element 40 are simultaneously driven will be described. Note that the driving here does not refer to a state in which only a voltage is applied to the liquid crystal display element 20 or a current only flows in the organic EL element 40, but is controlled according to the information displayed by the voltage or current, It refers to a state in which the reflected light intensity or the light emission intensity of the light emitting element is changed to display.

In the present embodiment, when the display device 1 is manufactured, as shown in Fig. 22, an unillustrated alignment film (trade name "JALS204 (Japanese synthetic rubber) having a property of vertically aligning liquid crystal molecules with respect to the insulating substrate 29 is employed. Made) "), and then subjected to non-fragrance treatment by rubbing, and then forming two sheets of the molded substrate on the insulating substrate 29 side and the molded substrate on the insulating substrate 21 side through a sealing resin (not shown). The substrate is brought into contact with each other, and a liquid crystal material having a negative dielectric anisotropy (trade name "MLC6608 (manufactured by Merck Co., Ltd.)") is injected as the liquid crystal layer 26 to form a liquid crystal display element 20. In addition, the display device 1 is completed by sequentially attaching the retardation plate 31 and the polarizing plate 32 to the surface of the insulating substrate 29. In addition, also in this embodiment, the phase difference of the phase difference plate 31 used was made into 1/4 with respect to the light of (lambda) = 550 nm.

In this embodiment, a drive circuit different from that in the fifth embodiment is used for the drive circuit. That is, in the present embodiment, the liquid crystal display element 20 and the organic EL element 40 are driven independently of each other.

A specific display operation of the display device 1 having the above configuration will be described with reference to FIGS. 27 to 29. FIG.

First, as shown in FIG. 27, the display mode of the liquid crystal layer 26 uses a liquid crystal layer 26 made of a liquid crystal material with negative dielectric anisotropy and a non-aligned alignment film of vertical alignment as described above. While black is displayed in a state where no voltage is applied, as shown in Fig. 28, the reflectance gradually increases due to the application of voltage, and the normal black mode is displayed, which performs white display.

That is, when the display device 1 is used under the external light 4, when no voltage is applied or when the drain voltage Vd is less than the common threshold voltage Vth, as shown in FIG. 27, the external light 4 is a polarizing plate ( 32) and after passing through the retardation plate 31, becomes circularly polarized light and is incident on the liquid crystal layer 26. When the drain voltage Vd of less than the common threshold voltage Vth is applied to the liquid crystal layer 26 by the liquid crystal TFT element 22, since the birefringence of the liquid crystal layer 26 is zero, the reflective pixel electrode At the point of reaching (25), for example, the circularly polarized state of the right circularly polarized light is maintained, but at the time of being reflected from the pixel electrode 25, the circularly polarized light of the reverse rotation of the left circularly polarized light is obtained. For this reason, after the reflected light passes through the retardation plate 31, it becomes linearly polarized light of an angle orthogonal to 90 degrees of the transmission axis of the polarizing plate 32. As shown in FIG. As a result, the reflected light of the external light 4 cannot pass through the polarizing plate 32, and the display becomes black. Therefore, as shown in Fig. 29A, the luminance of the liquid crystal display element 20 is about zero. At this time, as shown in Fig. 29B, the organic EL element 40 is also in an OFF state because it is less than the common threshold voltage Vth, and no current is supplied to the organic EL layer 41 in a non-light-emitting state. do.

Next, a case where white display is applied by applying a voltage will be described based on FIG. In addition, in the same figure, the optical state whose birefringence of the liquid crystal layer 26 which is a condition which reflectance is the highest is (lambda) / 4 is described.

As shown in Fig. 28, when the drain voltage Vd equal to or greater than the common threshold voltage Vth is applied to the liquid crystal layer 26, the liquid crystal layer 26 has birefringence and thus cannot maintain the circularly polarized state. Therefore, the reflected light of the external light 4 from the reflective pixel electrode 25 passes through the polarizing plate 32, and as shown in Fig. 29A, the luminance display of the liquid crystal display element 20 is white.

At this time, as shown in FIG. 28, since the EL TFT element 42 is also in an ON state, the organic EL element 40 as shown in FIG. 29B by the current supplied from the current supply line 2b. Becomes the light emitting state.

As shown in Fig. 22, the anode 43 constituting the organic EL element 40 is made of a reflective metal, and always reflects light regardless of the display signal. When mounting an organic EL display on a product having many opportunities for outdoor use such as a mobile phone, it is necessary to attach a circular polarizing plate to the observer side, but in this embodiment, the polarizing plate 32 necessary for the display of the liquid crystal layer 26 and The retardation plate 31 having a phase difference of λ / 4 wavelength has a function of making the reflection of the external light 4 almost zero.

In addition, although the liquid crystal layer 26 exists between the organic EL element 40 and the polarizing plate 32, the electrode is an insulating substrate like the counter electrode 27 in the portion of the liquid crystal layer 26 of the transmission region 12. It is not formed other than the (29) side. For this reason, as shown in Figs. 27 and 28, the liquid crystal layer 26 is always in the OFF state regardless of the applied voltage and maintains vertical alignment, and thus does not adversely affect the suppression of reflection of the external light 4.

In this embodiment, the liquid crystal layer 26 and the organic EL element 40 are simultaneously driven, but when the external light 4 is strong, the liquid crystal is turned off by cutting off the current supply to the organic EL element 40. It is possible to reduce the power consumption by displaying only on the layer 26.

Also in this embodiment, since the transparent insulating layer 24 is formed so as to cover the entire surface of the organic EL element 40 as in the fifth embodiment, the liquid crystal of the liquid crystal layer 26 is the organic EL element 40. ), It is possible to improve the reliability of the organic EL element 40.

As described above, in the display device 1 of the present embodiment, the organic EL element 40 and the liquid crystal display element 20 are driven independently of each other. For this reason, it becomes possible to drive the organic EL element 40 and the liquid crystal display element 20 separately. Moreover, as a structure for driving the organic EL element 40 and the liquid crystal display element 20 independently from each other, for example, each of the organic EL element 40 and the liquid crystal display element 20 is a source bus line 2a ... And a gate bus line 3..., Or a source bus line 2 a..., But a gate bus line 3.

In the display device 1 of the present embodiment, the liquid crystal display element 20 is normally black. Therefore, when driving the organic EL element 40 without driving the liquid crystal display element 20 when driving the liquid crystal display element 20 and the organic EL element 40 independently, the organic EL element 40 The periphery of the transmission area 12, which is the display area of, becomes black display which does not reflect light.

Therefore, the fall of contrast when the organic EL element 40 only drives light emission can be prevented.

  In addition, in the present embodiment, the liquid crystal display device 20 has the same structure and function as those of the first embodiment except for the structure of normally black.

In addition, although the display device which combined the liquid crystal display element 20 and the organic electroluminescent element 40 was demonstrated in this embodiment, it is not necessarily limited to this, The organic electroluminescent element 40 is the organic electroluminescent element mentioned above. (60, 70, 80) can be substituted.

(Example 7)

Another embodiment of the present invention will be described with reference to FIGS. 30 and 31 as follows. In addition, for the convenience of description, the same code | symbol is attached | subjected about the member which has the same function as the member shown in the drawing of said Example 1-Example 6, and the description is abbreviate | omitted. The various feature points shown in the first to sixth embodiments can also be applied to the present embodiment.

As described above, the liquid crystal display device and the organic EL display device have thin and light characteristics, respectively, and in the bright place, the reflective liquid crystal display device is effective for power consumption, while in the dark place, the organic EL can be obtained from the light utilization efficiency and shape. The display is valid. Therefore, it is considered that by forming the liquid crystal display element and the organic EL display element on one substrate, it is possible to compensate for the respective defects and to perform appropriate display under various environments.

However, in the display device 1, simply forming the liquid crystal display element and the organic EL display element on one substrate complicates the wiring and the driving circuit in the substrate, resulting in problems in manufacturing yield and cost. .

Thus, in the display device 1, the configuration of Fig. 23 according to the fifth embodiment is used to drive the liquid crystal display element 20 and the organic EL element 40. The gate bus line 3 which is a signal line and a scan signal line is used. This problem is solved by sharing the source bus line 2a, which is a signal line and a data signal line.

In the present embodiment, the driving method according to the driving circuit of the display device 1 will be described in detail.

As shown in Fig. 30, the scan line signal Vg from the gate bus line 3 ... has a high voltage at the time of selection, thereby turning on the liquid crystal TFT element 22, while a voltage at the time of non-selection. By lowering the state, the liquid crystal TFT element 22 is turned OFF. The data line signal Vs from the source bus line 2a is inverted with respect to the COM signal Vcom when the display is reflective, and the amount of reflected light due to the signal difference from the C0M signal Vcom is reduced. To adjust the display.

At this time, since the data line signal Vs from the source bus line 2a ... does not exceed the EL threshold voltage Vth (OLED) of the EL TFT element 42, the organic EL element 40 has no effect. No current flows and no light emission display is performed. On the other hand, when the data line signal Vs from the source bus line 2a ... exceeds the EL threshold voltage Vth (OLED) of the EL TFT element 42, a current flows in the organic EL element 40. Light emission is performed.

In the case of the light-emitting display, since the light emission amount is controlled by the signal value for GND, the data line signal Vs from the source bus line 2a ... is not inverted.

In the present embodiment, the liquid crystal display device 20 uses a normally white liquid crystal. For this reason, when the difference between the COM signal Vcom and the data line signal Vs from the source bus line 2a ... is large, dark display is performed. The light emitting display can be performed without reflection.

In this embodiment, the COM signal Vcom serving as the counter electrode 27 is AC driven with respect to the liquid crystal display element 20 even when the light emitting display is performed to prevent burn-in of the liquid crystal display element 20. The seizure is prevented by performing

In addition, in this embodiment, although it is comprised by one EL TFT element 42 as voltage-current conversion means, it is not necessarily limited to this. That is, as shown in Fig. 31, two or more elements may be used in order to suppress in-plane unevenness of the display device 1, and the operation voltage may be changed by the data line signal Vs from the source bus line 2a. What is necessary is just a structure with which threshold control and light emission amount can be suppressed.

As described above, in the present embodiment, the source bus lines 2a for driving the respective display pixels 10... Arranged in a matrix form by the liquid crystal display element 20 and the organic EL element 40. ) And the gate bus line 3 ... are shared with each other.

In the display device 1 of the present embodiment, the organic EL element 40 is applied by applying driving signals to the source bus line 2a ... and the gate bus line 3 ... to the liquid crystal display element 20. ) Can be driven. Therefore, the organic EL element 40 can be driven by the source bus line 2a ... and the gate bus line 3 ... for driving the liquid crystal display element 20. This may be achieved by commonizing each driver such as the source driver 6 and the gate driver 7. As a result, each display of the liquid crystal display element 20 and the organic EL element 40 can be performed without increasing the source bus line 2a ... and the gate bus line 3 ....

In this embodiment, the characteristics of the liquid crystal display element 20 are normally white. This is because when the voltage is not applied to the liquid crystal display device 20, the reflection area 11 is a white display, whereas when the voltage is applied to the liquid crystal display device 20, the reflectance becomes zero, and the reflection area 11 is It is displayed in black. In addition, as the voltage applied from the source bus line 2a to the liquid crystal display element 20 increases, black display is performed. Therefore, when driving the organic EL element 40, as described above, the liquid crystal display element 20 is in a driving state, and furthermore, the display is black.

As a result, since the circumference | surroundings of the transmission area | region 12 which is the display area of the organic electroluminescent element 40 turns into black display, the fall of contrast by the light emission drive of the organic electroluminescent element 40 can be prevented.

In the display device 1 of the present embodiment, the optical modulation device is composed of a liquid crystal display device 20. As a result, by forming the liquid crystal display element 20 and the organic EL element 40 in one display pixel 10, the low power consumption which is an advantage of the liquid crystal display element 20 and the high light which is an advantage of the organic EL element 40 are achieved. It is possible to provide the display device 1 in which utilization efficiency can be improved.

In this case, the liquid crystal display element 20 needs to be inverted in driving with respect to the potential of the counter electrode 27 due to the characteristics of the liquid crystal TFT element 22. On the other hand, as described above, it is sufficient for the organic EL element 40 to drive the non-inverting drive by current, that is, the direct current.

In this regard, in the display device 1 according to the present embodiment, a pixel electrode 25 having external light reflectivity is provided, and the counter electrode 27 facing the pixel electrode 25 is formed of the display pixel 10 on the opposite substrate side. It is placed on the front. In addition, when the display is performed by the liquid crystal display element 20, the driving is reversed with respect to the potential of the counter electrode 27, while when the display is performed by the organic EL element 40, the potential of the cathode 45, that is, GND. It is driven non-inverted with respect to the potential.

Therefore, when the liquid crystal display element 20 is used as the optical modulator, the liquid crystal display element 20 and the organic EL element 40 can be driven reliably and appropriately.

In the display device 1 of this embodiment, the organic EL element 40 is disposed behind the pixel electrode 25 having external light reflectivity. When the organic EL element 40 emits light forwardly, the display is performed only in the transmission region 12 so that the light is non-transmissive in the reflection region 11 where the pixel electrode 25 is present.

Therefore, when driving the organic EL element 40, the pixel electrode 25 of the liquid crystal display element 20 serves as a black matrix. Therefore, the contrast of the organic EL element 40 can be maintained.

In the present embodiment, the driving circuit for the case where the organic EL element 40 is disposed behind the pixel electrode 25 has been described, but the present invention is not necessarily limited thereto. The drive circuit described in this embodiment is also applicable to the case where the EL element 40 is disposed on the same layer as the liquid crystal layer 26.

In addition, although the display device in which the liquid crystal display device 20 and the organic EL device 40 are combined has been described in the present embodiment, the present invention is not limited thereto, and the organic EL device 40 may include the organic EL device 60 described above. 70, 80).

In addition, although the reflective liquid crystal display device 20 is used as the optical modulation device in the first to seventh embodiments, the present invention is not limited thereto. For example, the reflection amount of the light may be changed by using a mirror or the like. A display element may be used. It is also possible to use optical modulators such as electrophoretic displays, twisted ball displays, reflective displays using fine prism films, and digital mirror devices.

In addition, although the organic EL elements 40, 60, 70, and 80 were used in Examples 1 to 7 as the light emitting elements, they are not necessarily limited thereto. For example, light emission such as inorganic EL elements, LEDs (Light Emitting Diodes), etc. Applicable if the luminance is a variable element. It is also possible to use light emitting elements such as a field emission display (FED) and a plasma display.

In addition, the insulating board 29 as described in Example 1 thru | or 7 is not necessarily hard, but may be a film form.

In addition, although the liquid crystal TFT device 22 is used as the switching device for driving the liquid crystal display device 20 in the first to seventh embodiments, the present invention is not limited thereto, and for example, liquid crystal metal (MIM) for liquid crystal. It is also possible to use elements.

Example 8

Another embodiment of the present invention will be described with reference to FIG. In addition, for the convenience of description, the members having the same functions as the members shown in the drawings of the first to seventh embodiments are denoted by the same reference numerals, and description thereof will be omitted. In addition, the various feature points described in the first to seventh embodiments can also be applied to the present embodiment.

As described above, the liquid crystal display device and the organic EL display device have characteristics of thin and light, respectively, and the reflective liquid crystal display device is effective in power consumption in a bright place, while in a dark place, it is organic in light utilization efficiency and shape. The EL display device is effective. Therefore, by forming a liquid crystal display element and an organic EL display element on one substrate, it is possible to compensate for the respective drawbacks and to perform optimal display under various environments.

However, in the display device 1, simply forming a liquid crystal display element and an organic EL display element on one substrate complicates the wiring and the driving circuit in the substrate, resulting in problems such as yield or cost during manufacturing. do.

Therefore, in the display device 1, the configuration of Fig. 23 in Embodiment 5 makes the gate bus line the signal line and the scan signal line for driving the liquid crystal display element 20 and the organic EL element 40. The above problem is solved by sharing (3 ...) and the source bus line 2a ... which is a signal line and a data signal line.

In the present embodiment, a method different from that of the fifth embodiment will be described in detail with respect to the driving method of the drive circuit of the display device 1. The driving circuit is the same as that shown in FIG.

First, one field, which is the unit time of a video signal in one display pixel 10, is displayed as 1T as shown in FIG. 32A.

In the present embodiment, as shown in Figs. 32B and 32C, the scanning line signal Vg from the gate bus line 3... Is the voltage at the time of selection so that the voltage of the liquid crystal TFT element 22 shown in Fig. 23 is high. ) Is turned ON, and when not selected, the liquid crystal TFT element 22 is turned OFF by lowering the voltage.

Further, the scan line signal Vg is selected plural times between one field T to be in an ON state. Note that the time intervals for selecting the scan line signals Vg are not equal intervals but are a power of two powers. That is, in FIG. 32B, one field T is divided into 2 ⁰ : 2 ¹ : 2 ² . As a result, one field T has intervals of (1/7) T, (2/7) T, and (4/7) T. Although there is no problem in driving even if the time intervals are equal intervals, the number of gray scales can be increased by reducing the number of selections of the scan line signal Vg by setting the power of two powers. In other words, by dividing one field T into 2 ⁰ : 2 ¹ : 2 ² and putting each divided part individually, the eight lighting types are considered in consideration of the total lighting time in one field T. Gradation can be displayed.

In this embodiment, eight types of gradations are represented by turning ON three scan line signals Vg, for example, between one field T. However, the present invention is not limited to this, and the number of times is increased. By making it possible, the number of gradations on the display can be further increased. That is, in general, when dividing a plurality of one field T which is a unit time of a video signal into a plurality, each division width is 1 (= 2 ⁰ ): 2 ¹ : 2 ² : ...: 2 ⁿ (n is a positive integer) This can be divided so as to be at intervals of. Thereby, 2 ^{n + 1} grayscales can be displayed. In addition, the number of gradations can be increased by reducing the number of selections of the scan line signal Vg.

Specific driving methods of the reflective display and the light emitting display will be described below.

First, in the case of reflective display, as shown in FIG. 32B, the data line signal Vs from the source bus line 2a ... shown in FIG. 23 performs inversion driving with respect to the COM signal Vcom. The amount of reflected light is changed by a binary signal from the COM signal Vcom. In addition, ON and OFF are performed in three scan line signals Vg, and the amount of reflected light is adjusted in time to display. That is, the amount of reflected light is adjusted by increasing or decreasing the reflection time.

In addition, since the liquid crystal display element 20 uses a normally white liquid crystal in this embodiment, in the driving signal shown in Fig. 32B, when the period (4/7) T and the period (1/7) T, On the other hand, in the period (2/7) T, it is in the dark state, and both of the first field and the second field are displaying the fifth gradation. That is, in the period (2/7) T, for example, the COM signal Vcom is in the ON state, while the data line signal Vs is in the OFF state. As a result, since the voltage is applied to the liquid crystal display element 20, it is in the dark state in the period (2/7) T.

At this time, the data line signal Vs from the source bus line 2a ... does not exceed the EL threshold voltage Vth (OLED) of the EL TFT element 42 shown in Fig. 23, No current flows through the organic EL element 40, and no light emission display is performed.

On the other hand, when performing light emission display, as shown in Fig. 32C, the data line signal Vs from the source bus line 2a ... is the EL threshold voltage Vth of the EL TFT element 42. By exceeding the OLED, a current flows through the organic EL element 40 to perform light emission display. Further, when the EL TFT element 42 is smaller than the EL threshold voltage Vth (OLED), light emission is not performed.

In this embodiment, the scan line signal Vg is turned ON three times between one field T, and the organic EL element 40 is turned ON and OFF within the scan line signal Vg three times. As in (20), display is performed by adjusting the amount of emitted light in time. Specifically, as shown in Fig. 32C, it is in the ON state during the periods (4/7) T and (1/7) T, while in the period (2/7) T, the state is turned off, and the first field is shown. And any of the second fields indicate the fifth gray scale.

In the light emitting display, since the ON and OFF of the light emission are controlled by the signal for GND, the COM signal Vcom becomes constant and the data line signal Vs from the source bus line 2a ... is inverted. Do not drive. In the present embodiment, the liquid crystal display device 20 uses a normally white liquid crystal as described above. Therefore, since the difference between the COM signal Vcom and the data line signal Vs from the source bus line 2a is always a large value, the liquid crystal is always dark display and the reflective display portion. Can perform light emission display without reflecting the external light 4.

In the present embodiment, when the light emission display is performed, the data line signal Vs from the source bus line 2a ... is changed by making the C0M signal Vcom constant. Therefore, by turning the organic EL element 40 ON and OFF, AC driving is performed on the liquid crystal display element 20 with respect to the COM signal Vcom, thereby preventing burning.

In addition, in this embodiment, although it is comprised by one EL TFT element 42 as voltage-current conversion means, it is not necessarily limited to this. That is, as shown in Fig. 31, two or more elements may be used in order to suppress in-plane unevenness of the display device 1, and the operation voltage is changed by the data line signal Vs from the source bus line 2a. What is necessary is just a structure with which threshold control is possible.

As described above, in the present embodiment, the source bus lines 2a for driving the respective display pixels 10... Arranged in a matrix form with the liquid crystal display element 20 and the organic EL element 40 are provided. ) And the gate bus line 3 are shared with each other.

In addition, in the display device 1 of the present embodiment, the organic EL device is applied by applying driving signals to the source bus line 2a ... and the gate bus line 3 ... to the liquid crystal display element 20. 40 can be driven. Therefore, the organic EL element 40 can be driven by the source bus line 2a ... and the gate bus line 3 ... for driving the liquid crystal display element 20. This may be the case where each driver such as the source driver 6 and the gate driver 7 is common. As a result, each display of the liquid crystal display element 20 and the organic EL element 40 can be performed without increasing the source bus line 2a... And the gate bus line 3...

In this embodiment, the characteristics of the liquid crystal display device 20 are normally white. This is because in the state where no voltage is applied to the liquid crystal display device 20, the reflection area 11 is white display, while when the voltage is applied to the liquid crystal display device 20, the reflectance becomes zero and the reflection area 11 ) Becomes a black display. In addition, as the voltage applied from the source bus line 2a to the liquid crystal display element 20 increases, black display is performed.

Therefore, when driving the organic EL element 40, as described above, the liquid crystal display element 20 is in a driving state, and furthermore, the display is black.

As a result, since the circumference | surroundings of the transmission area | region 12 which is a display area of the organic electroluminescent element 40 turns into black display, the fall of contrast by driving light emission of the organic electroluminescent element 40 can be prevented.

In addition, in the display device 1 of the present embodiment, the optical modulation element is composed of a liquid crystal display element 20. As a result, by forming the liquid crystal display element 20 and the organic EL element 40 in one display pixel 10, the low power consumption which is the advantage of the liquid crystal display element 20 and the high which is the advantage of the organic EL element 40 are high. The display device 1 in which light utilization efficiency can be provided can be provided.

In this case, the liquid crystal display element 20 should be inverted and, in other words, alternating current driven with respect to the potential of the counter electrode 27 due to the characteristics of the liquid crystal TFT element 22. On the other hand, as described above, the organic EL element 40 is sufficient to be driven by non-inverting driving by current, that is, by direct current driving.

In this regard, in the display device 1 of the present embodiment, the pixel electrode 25 having the external light reflectivity is provided, and the counter electrode 27 facing the pixel electrode 25 has the display pixel 10 on the opposite substrate side. Is provided on the front. In addition, when the display is performed by the liquid crystal display element 20, the driving is reversed with respect to the potential of the counter electrode 27, while when the display is performed by the organic EL element 40, the potential of the cathode 45, that is, GND. It is driven non-inverted with respect to the potential.

Therefore, when the liquid crystal display element 20 is used as the optical modulation element, the liquid crystal display element 20 and the organic EL element 40 can be driven reliably and appropriately.

In addition, in the display device 1 of this embodiment, the organic EL element 40 is provided on the rear side of the pixel electrode 25 having external light reflectivity. When the organic EL element 40 emits light forwardly, the display is performed only in the transmissive region 12, and the light becomes non-transmissive in the reflective region 11 where the pixel electrode 25 is present.

Therefore, when driving the organic EL element 40, the pixel electrode 25 of the liquid crystal display element 20 serves as a black matrix. Therefore, the maintenance of the contrast of the organic EL element 40 can be realized.

In addition, in the driving method of the display device 1 according to the present embodiment, one field T which is a unit time of a video signal in each display area 10 is divided into a plurality, and the liquid crystal display element 20 or organic light is divided for each division period. The EL element 40 is turned ON and OFF.

Therefore, it is possible to control the total ON time of the liquid crystal display element 20 or the organic EL element 40 in one field T, and also to increase the kind of lighting patterns thereof and to drive them efficiently. .

In addition, by controlling the ON time of the liquid crystal display element 20 or the organic EL element 40 in this manner, the gray scale of the video signal can be displayed.

Therefore, when the liquid crystal display element 20 and the organic EL element 40, which are two display elements, are formed in the display area 10, the circuit configuration is prevented from being complicated, and the yield and cost at the time of manufacture are realized. In addition, a method of driving the display device 1 capable of performing gray scale display with high efficiency can be provided.

Further, in the driving method of the display device 1 of the present embodiment, when dividing one field, which is the unit time of the video signal in each display area 10 into plural, each division width is 1 (= 2 °): 2 ¹ : 2 ² : Split at intervals of 2 ⁿ (n is a positive integer).

That is, one field T is divided by a power of two, and the liquid crystal display device 20 or organic light is divided for each division period, that is, period (4/7) T, period (2/7) T, and period (1/7) T. By turning on the EL element 40, the total ON time of the liquid crystal display element 20 or the organic EL element 40 in one field T can be controlled, and the type of the lighting pattern is increased. These can be driven efficiently.

As a result, by using this division method, 2 ^{n + 1} gray scales can be displayed, and the number of gray scales can be increased by reducing the number of selections of the scan line signal.

In this embodiment, the driving circuit for the case where the organic EL element 40 is disposed behind the pixel electrode 25 has been described. However, the present invention is not necessarily limited thereto, and the organic EL element 40 is a liquid crystal. Also in the case where the layer 26 is provided on the same layer, the driving circuit described in this embodiment is applicable.

In addition, although the reflective liquid crystal display device 20 is used as the optical modulation device in the above-described embodiment, the present invention is not necessarily limited thereto. For example, a display that can be displayed by turning the reflection amount of light on and off using a mirror or the like can be displayed. You may use an element. It is also possible to use optical modulators such as electrophoretic displays, twisted ball displays, reflective displays using fine prism films, and digital mirror devices.

In addition, although the organic EL element 40 is used as the light emitting element, the organic EL element 40 is not necessarily limited thereto. For example, the organic EL element 60, 70, 80 can be used, and the inorganic EL element and LED (Light Emitting) can be used. Applicable as long as it is an element capable of controlling ON and OFF light emission such as a diode). In addition, a light emitting device such as a field emission display (FED) or a plasma display may be used.

Note that the insulating substrate 29 described in the above embodiment is not necessarily hard but may be a film.

In the above embodiment, the liquid crystal TFT element 22 is used as the switching element for driving the liquid crystal display element 20. However, the liquid crystal TFT element 22 is not necessarily limited thereto. For example, a liquid crystal metal insulator metal (MIM) element is used. It is also possible.

(Example 9)

Another embodiment of the present invention will be described below with reference to FIGS. 33 to 40. In addition, for the convenience of description, the same code | symbol is attached | subjected about the member which has the same function as the member shown in the drawing of said Example 1-Example 8, and the description is abbreviate | omitted. The various features described in the first to eighth embodiments can also be applied to the present embodiment.

In this embodiment, a case of manufacturing an organic EL display device which is a single light emitting element will be described.

First, in the organic EL display device 100 of this embodiment, as shown in Fig. 33, a TFT driving circuit portion and an EL layer are formed between two first substrates and an insulating substrate l21 · 129 serving as a second substrate.

A TFT circuit 142 is formed on one insulating substrate 121, and an insulating planarization film 123 serving as a protective film is formed on the TFT circuit 142, and the pixel electrode 125 is formed on the planarization film 123. Is formed. The pixel electrode 125 is connected to the TFT circuit 142 through a through hole disposed in the planarization film 123. The planarization film 123 serves to prevent intrusion of moisture or the like into the TFT circuit 142 and to planarize the top surface of the TFT circuit 142. The insulating substrate 12l, the TFT circuit 142, the planarization film 123, and the pixel electrode 125 form a TFT circuit side substrate 151.

On the other hand, on the other insulating substrate 129 disposed at the position opposite to the TFT circuit side substrate 151, a black matrix 133 is disposed to hide the gap between the elements and block light from the transverse direction of the light emitting layer. In addition, on the black matrix 133, an electrode line 165a for supplying power to the EL layer is formed along the black matrix 133. Further, an anode electrode 165 made of a transparent conductive film serving as an anode of the EL layer is formed on these.

The anode electrode (anode) 165 is usually formed of an oxide of ITO, but a conductor such as an oxide has a higher resistance value than that of a metal. For this reason, the power loss by the anode electrode (anode) 165 which becomes a transparent conductive film cannot be neglected depending on the distance from the end surface of a board | substrate used as a power supply source. For the above reason, in the present embodiment, the electrode line 165a as the power supply electrode made of the metal electrode in the shape along the black matrix 133 is formed.

The organic EL layer 166 is formed on the anode electrode (anode) 165, and the organic EL layer 166 is composed of a hole transport layer 164, a light emitting layer 163, and an electron transport layer 162 here. Take A cathode electrode (cathode) 161 is formed on the electron transport layer 162. The structure of the EL is completed from the insulating substrate 129 to this cathode electrode (cathode) 161. The organic EL element 160 is composed of an anode electrode (anode) 165, a hole transport layer 164, a light emitting layer 163, an electron transport layer 162, and a cathode electrode (cathode) 161.

In this embodiment, a cathode protective electrode material 167 that protects the cathode electrode (cathode) 161 is formed next to the cathode electrode (cathode) 161. This is because the cathode electrode (cathode) 161 is easily oxidized by oxygen and moisture, and is formed on the cathode electrode (cathode) 161 to protect the cathode electrode (cathode) 161 and the TFT circuit. It is arrange | positioned in order to make connection with the side board | substrate 151 easy. In other words, it is preferable to form the cathode protective electrode material 167 continuously with the cathode electrode (cathode) 161 in view of reliability.

  Further, the TFT circuit side plate 151 and the insulating substrate 129 on which the organic EL element 160 is formed are connected by the connection electrode 168. The connection electrode 168 is formed of a conductive paste and a conductive resin. After forming these in the both board | substrate side, you may adhere | attach them, and you may form only in one board | substrate. In addition, a plurality of these materials may be used to form a layer and may be connected.

In FIG. 33, the organic EL layer 166 is composed of a hole transport layer 164, a light emitting layer 163, and an electron transport layer 162. However, the configuration is not limited thereto. As shown, it is possible to apply the polymer EL material 173 to the organic EL layer and to apply the polymer EL material 173 with an ink jet coating apparatus at the time of formation. In the case of applying the ink jet coating apparatus in this manner, the guide 174 is provided below the black matrix 133 in order to prevent the polymer EL material 173 from flowing around. That is, the guide 174 is formed in advance on the rectangular frame, and the polymer EL material 173 is applied to the inside of the guide 174 by ink jet coating. In addition, although the organic EL layer 166 is made of one layer, as described above, a plurality of polymer EL materials 173...

Next, a manufacturing method of the organic EL display device 100 will be described with reference to Figs.

First, as shown in FIG. 35A, the black matrix 133 is formed on the insulating substrate 129 using a light shielding material composed of chromium oxide or fine particles of TiN or TiO. The thickness of the black matrix 133 may be about 1000 to 2000 micrometers. Chromium oxide can be formed using a vacuum film formation by sputtering or vapor deposition. Further, the fine particles of TiN and TiO may be dispersed and applied to a resist, followed by mask exposure, development and baking to form a pattern.

Next, an electrode line 165a for power supply is formed, but this is formed as follows. That is, aluminum (Al) and titanium (Ti) are sequentially sputtered on the entire surface in this order, followed by pattern formation using a resist, followed by dry etching to form an electrode pattern. Aluminum (Al) is, for example, 3000 kPa and titanium (Ti) is 800 kPa. And ITO is formed into a film by this 1000 micrometers sputtering method, and it is set as the anode electrode (anode) 165 on this. The same drawings (a) to (c) show a method of forming the organic EL layer 166 on the insulating substrate 129 thus formed by the mask deposition method.

First, as shown in FIG. 35A, the shadow mask 155 is disposed on the substrate upper surface, and a material which becomes the organic EL layer 166 is formed in order through the gap between the shadow mask 155. FIG. Specifically, as shown in Figs. 35A and 35B, the hole transport layer 164, the light emitting layer 163, and the electron transport layer 162 are stacked in this order.

Examples of the material for the hole transport layer 164 include a phthalocyanine compound, a naphthalocyanine compound, porphyrins, oxadiazoles, triazoles, imidazoles, tetrahydroimidazoles, oxazoles, stilbenes, and the like.

Subsequently, examples of materials that can be used as the light emitting layer 163 composed of low molecular weight light emitting materials that emit respective colors include, for example, naphthalin, anthracene, phenanthrene, pyrene, tetracene, fluorescein, perylene, phthaloperylene, Naphthaloperylene, perinone, phthaloperinone, naphthaloperinone, diphenylbutadiene, tetraphenylbutadiene, coumarin, quinoline metal complex, imine, diphenylanthracene, diaminocarbazole, quinacridone, ruburan, etc. Can be mentioned.

Examples of the material of the electron transport layer 162 include fluorenone, anthraquinodimethane, diphenylquinone, thiopyran dioxide, oxadiazole, thiadiazole, tetrazole and perylenetetracarboxylic acid.

35C, an electrode material having a small work function value is formed as the cathode electrode (cathode) l 61 on the organic EL layer 166. As shown in FIG. In addition, the work function refers to the minimum energy required to pick up electrons from the solids such as conductors and semiconductors to the outside world.

As the cathode electrode (cathode) 161, materials such as magnesium (Mg), calcium (Ca), lithium (Li), MgAg alloy, and LiA1 alloy can be used.

As the cathode protective electrode material 167, metals such as aluminum (Al), nickel (Ni), titanium (Ti), tantalum (Ta), and gold (Au) can be used. Here, 500 to 800 Li of LiA1 alloy was formed as the cathode electrode (cathode) 161, and 1000 금 of gold (Au) was formed as the cathode protective electrode material 167.

  In this way, the board | substrate of the side which has the organic EL layer 166 is formed. Then, the shadow mask 155 is moved to the next pixel to form the same thing. As a result, as shown in Fig. 33, a gap is formed between the organic EL layer 166 of the predetermined pixel and the organic EL layer 166 of the pixel adjacent thereto.

Next, referring to Figs. 36A and 36B, a step of forming a connection electrode 168 as a contact layer for making a connection with a substrate on the organic EL element 160 side in the TFT circuit side substrate 151 is made. Explain.

36A, in the TFT circuit side substrate 151, a connecting electrode 168 is formed over the pixel electrode 125. As shown in FIG.

Conductive paste, conductive resin, or the like may be used for the material of the connection electrode 168. In particular, when a particulate metal having a particle size of nanoscale is used as the conductive paste, the particle metal has a small particle diameter, so that there is a high probability of connecting the particles between the particles and the electrodes, which makes it possible to reliably perform electrical bonding.

As the conductive resin, for example, photosensitive resin in which the conductive particles described in Japanese Patent Application Laid-Open No. Hei 11-249299 are dispersed (manufactured by Fujifilm Co., Ltd.) or the magazine "1986 The Chemical Society of Japan", "CHEMISTRY LETTERS, pp. 469-472," 1986 "and the like, and the photosensitive conductive polymer using the polypyrrole can be used. In detail, Japanese Patent Application Laid-Open No. 11-249299 discloses a technique related to a photosensitive dispersion in which conductive particles such as carbon black are dispersed and a photosensitive sheet, and that a pattern can be formed by exposure and development. In addition, "CHEMISTRY LETTERS, pp. 469-472, 1986" discloses that polypyrrole provided with conductivity can be formed by photochemically polymerizing a pyrrole monomer, and it is also disclosed that it is patterned and used as an electrode material.

Here, as shown in Fig. 36A, for example, a photosensitive conductive material in which carbon black is dispersed in a resist is applied onto the TFT circuit side substrate 151, and then exposed and developed using a shadow mask 155. As shown in Fig. 36B, the process was performed so that the connection electrode 168 remained only in each pixel portion.

37A and 37B, the TFT circuit side substrate 151 and the counter substrate 152 on the organic EL element 160 side are matched with each other and fixed. Here, the organic EL element 160 is electrically connected to the TFT circuit side substrate 151 by the connecting electrode 168, but preferably both of these TFT circuit side substrates 151 and the counter substrate 152 in advance. It is better to form a conductive resin and to make electrical contact with conductive resins. This is because contact failure due to an oxide film or the like on the metal surface can be prevented, and a contact can be easily taken by using the elasticity of the resin.

Next, the case where the organic EL layer 166 is formed using the polymer EL material 173 will be described.

As shown in FIG. 38A, a guide 174 is formed on the anode electrode (anode) 165 of the counter substrate 152. As shown in FIG. This guide l74 is formed by a photolithography process or ink jet application using a resist or polyimide. FIG. 38B shows a case where an organic EL layer made of the polymer EL material 173 is formed in the guide 174 by ink jet application. Examples of the polymer EL material 173 include polyphenylene vinylene, polyfluorene, polythiophene, polyvinylcarbazole, and the like.

Next, as shown in FIG. 38C, the cathode electrode (cathode) 161 and the cathode protective electrode material 167 are formed, and then a conductive polymer material as the contact electrode 168 as a contact layer is applied. As the cathode electrode (cathode) 161, as described above, aluminum (Al), magnesium (Mg), AlMg, AlLi material, or the like can be used. Here, AlLi metal material was formed about 1000 kPa by the vapor deposition method. Further, a conductive polymer material is formed thereon as the connection electrode 168. On the other hand, as shown in Fig. 39, the TFT circuit side substrate 151 is formed by applying, for example, a connecting electrode 168 of a photosensitive conductive resin with an ink jet apparatus.

40A and 40B, the TFT circuit side substrate 151 and the counter substrate 152 are bonded together. That is, the TFT circuit side substrate 151 and the counter substrate 152 on the side of the organic EL element 160 are matched with each other and adhesively fixed. Here, the organic EL element 160 is electrically connected to the TFT circuit side substrate 151 by the connection electrode 168, but preferably in advance to both of these TFT circuit side substrates 151 and the counter substrate 152. It is better to form a conductive resin and to make electrical contact with each other. This is because contact failure due to an oxide film or the like on the metal surface can be prevented, and a contact can be easily taken using the elasticity of the resin.

In addition, the connecting electrode 168 as an adhesive layer may be coated with an epoxy resin or the like on the outer circumference of the adhesive surface of the TFT circuit side substrate 151 and the opposing substrate 152 to be adhered, and may be hardly bonded during bonding. Moreover, you may apply an adhesive agent to the part covered by the black matrix 133 between pixels.

As described above, the organic EL display device 100 and the manufacturing method thereof according to the present embodiment are made of a light emitting display element alone, and the counter substrate 152 forming the organic EL element 160 as a light emitting element is an organic EL element 160. ) Is formed up to the cathode electrode (cathode) 161, which is a light emitting element electrode, and then adhered to the TFT circuit-side substrate 151.

As a result, the light emitted from the organic EL element 160 is not the TFT circuit side substrate 151 on which the driving circuit for driving the organic EL element 160 is formed, but from the counter substrate 152 set opposite thereto. It is possible to exit. For this reason, since the light output direction is the same as the prior art, the following basic merits are the same as compared with the structure emitted to the TFT circuit side substrate 151 side.

First, the TFT circuit side substrate 151 on which the driving circuit is disposed and the organic EL element 160 can be formed separately. For this reason, since a manufacturing process can be independently organized, reliability is improved, without being influenced by temperature, a gas, a chemical | medical agent, etc.

In addition, light can be emitted to the counter substrate 152 on which the organic EL element 160 is formed by the above configuration. As a result, the light emitting area can be set wide without being influenced by the opening ratio of the driving circuit side, whereby high luminance can be achieved. In addition, since the light emitting area is wide, the amount of current per unit area for obtaining the same brightness can be suppressed, so that the power consumption can be realized by extending the life and improving the luminous efficiency.

In addition, since light is not emitted to the TFT circuit side substrate 151 on which the drive circuit is formed, the TFT circuit side substrate 151 can form a drive circuit on the entire surface. Therefore, since the size of the TFT (Thin Film Transistor) of the driving circuit can be freely set or there is a margin in the TFT formation region, a circuit for fine control can be formed. In addition, since a margin is also provided in the wiring width, the reliability of the driving circuit can be improved, and the yield is improved.

By the way, as the organic EL display device 100, the cathode electrode (cathode) 161 of the organic EL element 160 needs to use a material having a small work function. Examples of such materials include magnesium (Mg), calcium (Ca), calcium (Ca), lithium (Li), and the like, but these are unstable materials and are likely to deteriorate due to moisture or oxygen in the atmosphere. In addition, some of the materials to be contacted may deprive oxygen of the material and cause a chemical reaction. Therefore, it is preferable to coat with a stable metal so as to protect immediately after formation. However, none of the above prior art configurations can be taken to protect the cathode electrode (cathode) 161.

On the other hand, in this embodiment, the counter substrate 152 which forms up to the cathode electrode (cathode) 161 in the organic EL element 160 has the cathode electrode (cathode) on the cathode electrode (cathode) 161. After forming the cathode protective electrode material 167 as a protective electrode for protecting the 161, it is bonded to the TFT circuit side substrate 151.

That is, when the opposing substrate 152 forming up to the cathode electrode (cathode) 161 is bonded to the TFT circuit-side substrate 151, the cathode protection electrode material 167 protecting the cathode electrode (cathode) 161. By arranging, the performance deterioration of the cathode electrode (cathode) 161 due to exposure to moisture or oxygen in the atmosphere during bonding can be prevented.

Further, preferably, the cathode electrode (cathode) 161 and the cathode protection electrode material 167 for protecting the same are continuously formed in the same process, whereby deterioration of the cathode electrode (cathode) 161 can be prevented. At this time, the formation thickness of the cathode protective electrode material 167 can be set freely, so that the cathode electrode (cathode) 161 can be configured to have a sufficient thickness so as not to contain components that cause deterioration such as oxygen. .

In addition, in the organic EL display device 100 and the manufacturing method of the present embodiment, the counter substrate 152 which forms up to the cathode electrode (cathode) 161 in the organic EL element 160 is a TFT circuit-side substrate ( A contact layer such as a conductive paste or a conductive resin is formed on the contact surface with the pixel electrode 125, which is the driving circuit electrode of the 151, and then bonded to the pixel electrode 125 of the TFT circuit side substrate 151.

As a result, since electrical contact at the time of adhesion can be taken more reliably, there is no disconnection or point contact at a joining surface, and the image quality improvement without luminance unevenness can be aimed at.

By the way, in the organic EL display device 100 and its manufacturing method of the present embodiment, when the opposing substrate 152 formed up to the cathode electrode (cathode) 161 is bonded to the TFT circuit side substrate 151, The cathode electrode (cathode) 161 on the opposite side faces the TFT circuit side substrate 151.

By the way, since a transparent electrode is a conductor normally using an oxide, resistance is high compared with a metal. Therefore, in a display panel having many pixels, there is a possibility that a voltage drop occurs first in the transparent electrode in the case where the telephone station simultaneously emits light. In the case of the prior art in which the TFT circuit side substrate 151 is used as the anode electrode, power supply to the TFT of the driving circuit is not a problem because it is a metal wiring, but a transparent conductor having a specific resistance higher than that of a metal having about two units is used. In this case, luminance unevenness due to voltage drop cannot be ignored.

Therefore, in the present embodiment, an anode electrode (anode) 165 made of a transparent electrode of the organic EL element 160 is disposed on the side of the outgoing light on the counter substrate 152, and the anode electrode (anode) 165 is disposed. An electrode line 165a as a power supply electrode is provided in parallel.

Therefore, the voltage drop can be suppressed, for example, by providing the electrode line 165a made of metal wiring along the black matrix 133 on the emission side, so that no luminance stain occurs.

In addition, in the present embodiment, the features of the organic EL display device 100 made of the light emitting display element alone are described, but this feature is provided by the non-light emitting display element and the light emitting display element described in the first to eighth embodiments. It can be applied also to what is, and has the same effect.

As described above, according to the display device of the present invention, in a bright environment, the power consumption can be lower than that of the display device in which the transmissive non-light emitting display element and the reflective non-emitting display element are incorporated, and the luminance is lowered so that the display life can be extended. And improved reliability. In addition, since the display device of the present invention does not need to provide a backlight separately, the display device can be made thinner and smaller in size, and power supply means and control are unnecessary as compared to the conventional liquid crystal display device. have.

In addition, according to the display device of the present invention, it is possible to set the maximum luminance lower than that of only the light emitting display element, thereby realizing longer life and improved reliability.

Claims (56)

In the display area, a first display area comprising a non-light emitting display element in which an optical modulator including a liquid crystal display element having a pixel electrode reflects external light and displaying the light, and a light emitting display element in which the light emitting element directly modulates and displays the light. A second display area comprising: a first display area and a second display area; And a liquid crystal layer of the optical modulator in the second display area. The display device according to claim 1, further comprising a first substrate and a second substrate facing each other, wherein both the optical modulator and the light emitting element are provided between the first substrate and the second substrate. delete The display device according to claim 1, wherein the liquid crystal layer of the optical modulation element and the light emitting layer of the light emitting element are provided in the same layer. The display device according to claim 2, wherein a driving element for driving the light emitting element and a driving element for driving the light modulation element are formed on the first substrate side, while the light emitting element is formed on the second substrate side. . The display device according to claim 2, further comprising an iron portion provided for height adjustment on either one of the first substrate side and the second substrate side, wherein the light emitting element is formed on the iron portion. The display device of claim 6, wherein the convex portion is formed of a conductive resin. The display device of claim 6, wherein the convex portion comprises an insulating layer. The display device according to claim 6, further comprising a conductive material on a bonding surface of the light emitting element electrode of the light emitting element and the first substrate side or the second substrate side. The display device according to claim 1, wherein the light emitting layer of the light emitting element and the liquid crystal layer of the light modulation element are adjacent to each other via a protective layer. The display device of claim 10, wherein the protective layer has a light blocking function. The display device of claim 1, wherein the light emitting device and the light modulation device are driven independently of each other. The display device of claim 1, wherein the light emitting device and the light modulation device are driven by sharing a signal line. The display device according to claim 2, further comprising a driving element for driving the light emitting element and the optical modulation element, wherein the driving element is formed on either the first substrate side or the second substrate side. The display control means according to claim 1, further comprising an external light detecting means for detecting external light, wherein the display control means for selectively displaying both or one of the light emitting element and the optical modulation element based on the detection result of the external light by the external light detecting means. Display device further comprising. The display device according to claim 1, wherein the light modulator is a reflective liquid crystal display and the light emitting element is an organic electroluminescent element. The display device according to claim 1, wherein the display surface side electrode of the optical modulation element and the display surface side electrode of the light emitting element are formed on the same layer by the same material. The display device according to claim 1, wherein the light emitting element is selectable when the light modulator is in a bright display state. The display device according to claim 1, wherein the optical modulator and the light emitting element are arranged in an adjoining state, and when the one of the optical modulator and the light emitting element is in a bright display state, the other becomes a dark display state. In the manufacturing of the display device according to claim 2, after the driving circuit is formed on the first substrate and the light emitting element is formed on the second substrate, the first substrate side and the driving circuit are formed. A method of manufacturing a display device, wherein the display device is integrated by joining the second substrate side on which the light emitting element is formed. A display device according to claim 20, wherein the light emitting layer of the light emitting element and the liquid crystal layer of the optical modulator are provided adjacent to each other via a protective layer, and the light emitting element and the protective layer may be formed first. Way. 21. The method according to claim 20, wherein after the conductive material is provided on the bonding surface between the light emitting element electrode of the light emitting element and the first substrate side or the second substrate side, the first substrate side and the second substrate side Method of manufacturing a display device to be bonded. 21. The light emitting device according to claim 20, wherein a light emitting element is formed on the second substrate up to two electrodes for light emitting elements, and then the first substrate side on which the driving circuit is formed and the second substrate side on which the light emitting element are formed are joined. Method for manufacturing a display device. The method of claim 20, wherein the light emitting device is made of an organic electroluminescent device, A second substrate side for forming the organic electroluminescent element is formed up to the cathode electrode in the organic electroluminescent element, and then bonded to the first substrate side. The first substrate side according to claim 24, wherein the second substrate side on which the cathode electrode in the organic electroluminescent element is formed is formed on the cathode electrode again after forming a protective electrode to protect the cathode electrode. Method of manufacturing a display device bonded to the. A driving circuit electrode is provided on a joining surface of the first substrate side to the second substrate side. On the second substrate side on which the cathode electrode in the organic electroluminescent element is formed, after providing the conductive material to the contact surface with the driving circuit electrode on the first substrate side, the driving circuit electrode on the first substrate side Method of manufacturing a display device bonded to the. The anode according to claim 24, wherein an anode electrode made of a transparent electrode in an organic electroluminescent element is provided on the emission light side on the second substrate side. The anode electrode is provided with a power supply electrode in parallel. In the display area, a first display area comprising a non-light emitting display element in which an optical modulator including a liquid crystal display element having a pixel electrode reflects external light and displays the light, and a light emitting display element in which the light emitting element directly modulates and displays the light. And a second display region comprising a first display region and a second display region, Further comprising a first substrate and a second substrate facing each other, wherein the optical modulator and the light emitting element are both provided between the first substrate and the second substrate, In the second display area, the liquid crystal layers of the light emitting device and the optical modulation device are sequentially stacked on the first substrate, And the optical modulator is a liquid crystal display. 29. The display device according to claim 28, wherein the light emitting element has an area substantially equal to or smaller than that of the second display area. 29. The display device according to claim 28, wherein the light emitting element is made of an organic electroluminescent element. delete 29. The display device according to claim 28, wherein the light emitting element and the light modulation element are driven independently of each other. The display device of claim 28, wherein the light emitting device and the light modulation device are driven by sharing a signal line. The display device according to claim 33, wherein the liquid crystal layer, which is an optical modulation layer of the liquid crystal display element, is in a horizontal alignment mode in the first display area and in a vertical alignment mode in the second display area. In the display area, a first display area for displaying by reflecting external light by a first electro-optical device including a liquid crystal display device having a pixel electrode, and a second display area for displaying by a second electro-optical device. Including the first display area and the second display area, Further comprising a first substrate and a second substrate facing each other, wherein the first electro-optic device and the second electro-optical device are both provided between the first substrate and the second substrate, Each data signal line and each scan signal line for driving each of the display regions arranged in a matrix form with the first electro-optic element and the second electro-optic element are shared with each other, And a liquid crystal layer of the optical modulator in the second display area. In the display area, a first display area comprising a non-light emitting display element in which an optical modulator including a liquid crystal display element having a pixel electrode reflects external light and displaying the light, and a light emitting display element in which the light emitting element directly modulates and displays the light. A second display area comprising a first display area and a second display area; Further comprising a first substrate and a second substrate facing each other, wherein both the optical modulator and the light emitting element is provided between the first substrate and the second substrate, Each data signal line and each scan signal line for driving each display area arranged in a matrix form with the optical modulation device and the light emitting device are shared with each other, And a liquid crystal layer of the optical modulator in the second display area. In the display area, a first display area comprising a non-light emitting display element in which an optical modulator including a liquid crystal display element having a pixel electrode reflects external light and displaying the light, and a light emitting display element in which the light emitting element directly modulates and displays the light. A second display area comprising a first display area and a second display area; Further comprising a first substrate and a second substrate facing each other, wherein both the optical modulator and the light emitting element is provided between the first substrate and the second substrate, By applying a drive signal to each data signal line and each scan signal line for driving each display area arranged in a matrix form with the optical modulation device, the light emitting device can be driven. And a liquid crystal layer of the optical modulator in the second display area. 37. The apparatus of claim 36, further comprising: voltage and current conversion means for converting a voltage into a current to drive the light emitting element, And a drain electrode of an optical modulation element transistor, which is a switching element for driving the optical modulation element, connected to the voltage and current converting means. The method of claim 38, wherein the voltage and current conversion means is made of a light emitting element transistor, And a threshold voltage of the light emitting element transistor for driving the light emitting element is larger than a driving voltage of the light modulation element. The method of claim 38, wherein the voltage and current conversion means is made of a light emitting element transistor, And an ON operating region of the light emitting element transistor and an ON operating region of the optical modulation element transistor for driving the optical modulation element are divided by a threshold voltage. The display device according to claim 38, wherein the characteristics of the optical modulation element are normally white. delete 39. The display device according to claim 38, further comprising a pixel electrode having external light reflectivity, and a counter electrode facing the pixel electrode is provided on the entire surface of the display area on the second substrate side. A display device which is driven with respect to the potential of the counter electrode when displaying by the optical modulator, while being driven by the potential of the reference electrode when displaying by the light emitting element. 37. The display device according to claim 36, wherein the light emitting element is provided on the rear side of the pixel electrode having the external light reflectivity, and when the light emitting element emits itself toward the display surface in front, the display is performed only in the second display area. And light is non-transmissive in the first display area in which the pixel electrode is present. In the driving method of the display device according to claim 36, A method of driving a display device in which one field, which is a unit time of a video signal in each display area, is divided into a plurality, and the optical modulation element or the light emitting element is turned on / off at each division period. 46. The method of claim 45, wherein when dividing one field, which is a unit time of a video signal in each display area, into a plurality of fields, each division width is 1: 2 ¹ : 2 ² : ...: 2 ⁿ A method of driving a display device, which is divided so as to be a positive integer interval. delete delete delete delete delete delete delete delete delete delete

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