JPH11329745A - Luminescent element and laminated display element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize color display with high picture quality and high reliability by setting the area being occupied by a light reflective cathode in the specified ratio or less to the whole display area of an organic luminescent display element and forming the remaining part so as to transmit light. SOLUTION: The area being occupied by a light reflective cathode is set in 2/3 or less the whole display area of an organic luminescent display element. A transparent electrode 2 made of tin indium oxide for injecting a hole, a hole transport layer 3 uniformly formed on the substrate surface on which the cathode is formed, an organic luminescent layer 4 which is an electron transport layer, a cathode layer 5 made of an silver magnesium alloy, divided in the lateral direction for injecting electrons, and a protecting layer made of silicon oxide uniformly formed on the cathode layer 5 are formed in order on a glass substrate 1. When an electric field is applied across the transparent electrode 2 and the cathode layer 5, holes and electrons are injected into the organic luminescent layer in the region where the electrode in the lateral direction crosses with the electrode in the longitudinal direction, and electroluminescence 8 is produced. The background of a window part 6 (about 2/3 the region) other than the cathode forming part is observed as transmitted light 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a new type of display utilizing the features of an organic EL device, and overcomes the drawbacks of the conventional colorization method of an organic light-emitting device to provide a high-quality and highly reliable color display. The present invention relates to a light emitting element for realizing a display and a multilayer display element.

[0002]

2. Description of the Related Art With the development of a highly information-oriented multimedia society, the development of flat display devices with low power consumption and high image quality has been activated. Non-emissive liquid crystal display elements have established their position with the feature of low power consumption, and their applications to portable information terminals and the like have been further enhanced.

On the other hand, the organic EL display is a self-luminous type and is very easy to recognize in a room where the display is most commonly used.
Research and development have been activated with the aim of realizing large-screen display and ultra-high-definition display, which are difficult to achieve with CRTs. Already, monochrome (green, yellow) character and number display has reached a technical level close to practical use. In the future, development of a new type display utilizing the characteristics of organic EL and expectation for a color display capable of displaying moving images will be expected. Is growing.

[0004] Organic EL has attracted attention because of
In 987, Tan et al. Deposited and formed an electrode layer for hole injection, an organic hole transport layer, an organic electron transporting light emitting layer, and an electrode layer for electron injection on a substrate, so that organic light emitting at a low voltage was obtained. It is derived from the demonstration that EL becomes feasible (Reference: CWTang et al. Appl. Phys. Lett. Vol.
51, p.913 (1987)).

An outline of a conventional organic EL device proposed by Tan et al. Is shown in FIG. On a glass substrate 81, an anode 82 made of a transparent conductive thin film (ITO) having a relatively large ionization potential such as indium tin oxide (ITO) and easy to inject holes is formed. Next, a hole transport layer 83 and an electron transporting light emitting layer 84 are sequentially formed on almost the entire surface. On the surface thereof, there is formed a cathode 85 made of a metal layer having a relatively low work function such as a silver-magnesium alloy (AgMg) and easy to inject electrons.

The light-emitting layer having an electron-transporting property generally has a lower work function than a metal. However, by using a metal having a low work function such as an AgMg alloy as a cathode, electron injection and its transport can be compared. Can be easily achieved. Further, since the hole transport layer has a relatively large ionization potential, injection and transport of holes are relatively performed by using a material having a large ionization potential such as gold (Au) or indium tin oxide (ITO) as the anode. Can be easily realized.

Therefore, by applying a positive DC voltage to the anode with respect to the cathode, holes are injected from the anode (ITO) 82 into the hole transport layer, and electrons are injected from the cathode 85 to the electron transporting light emitting layer. Is injected, and furthermore, in the light emitting layer near the junction between the hole transport layer and the electron transport layer (light emitting layer), these are combined to form excitons, thereby generating green light emission 86.
This light emission is observed through the transparent electrode and the substrate.
Needless to say, light emission can also be obtained by bonding the hole transporting organic light emitting layer and the electron transporting organic layer and injecting and transporting holes and electrons.

This light emitting principle is similar to an inorganic light emitting diode formed of gallium arsenide or the like. By injecting electrons and holes into a PN-junction compound semiconductor, electrons and holes are regenerated near the junction. It can correspond to the light emission by the combination. The electron transport layer can be compared with an N-type compound semiconductor, and the hole transport layer can be compared with a P-type compound semiconductor.

Thereafter, organic semiconductor materials and additive materials that emit blue or red light have been developed, and some methods for realizing color displays have been proposed, and color displays have been prototyped. Organic EL
The following five methods have been proposed as methods for realizing color displays. (1) A method in which three types of organic light emitting materials that emit red, green, and blue light are alternately arranged in a plane. (2) A method of laminating three types of organic light emitting materials that emit red, green, and blue light. (3) A method of forming an organic material that emits white light (green with a wide band threshold) and three types of resonator structures. (4) A method of combining a white light-emitting organic material with three primary color filters. (5) A method in which an organic material that emits blue light and a color conversion layer that converts light into three primary colors are combined.

[0010] However, major problems remain in each method. In the first method, since it is difficult to finely process an organic material, it is very difficult to realize a high-definition display. In the second method, it is difficult to form an element having high transmittance because the cathode is made of metal, and it is necessary to laminate at least two layers, and it is extremely difficult to form a color display with good image quality. is there. In the third method, it is very difficult to realize a uniform color display over a large area because the emission color largely depends on the thickness of the thin film forming the resonator. Although the fourth and fifth methods are relatively excellent in realizing high image quality, the fourth method has no choice but to wait for the development of a highly reliable white light emitting material at present. In the fifth method, it is difficult to realize a display with low conversion efficiency of light from blue to red and high luminance.

[0011]

As described above, it has been difficult to realize a practical high-quality color display with the conventional organic light-emitting device.

The present invention provides a new type of display utilizing the features of the organic EL, and also overcomes the drawbacks of the conventional method of colorizing an organic light emitting device to realize a color display with high image quality and high reliability. Things.

[0013]

The present invention provides an organic light-emitting display device comprising a transparent substrate, a transparent electrode, an organic semiconductor layer including a light-emitting layer, and a light-reflective cathode, which are sequentially formed on a transparent substrate. Light-emitting element, wherein the area occupied by is less than two-thirds of the total display area of the organic light-emitting display element, and the remaining one-third or more is light-transmitting,
And a transparent electrode, an organic semiconductor layer including a light-emitting layer, and a light-reflective cathode are sequentially formed on a transparent substrate, and the area occupied by the light-reflective cathode is the entire area of the organic light-emitting display element. A multi-layer display element comprising at least one organic light-emitting element having a display area of two-thirds or less.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention relates to an organic light emitting display device comprising a transparent substrate, a transparent electrode, an organic semiconductor layer including a light emitting layer, and a light reflective cathode formed in this order. The area occupied by the light-reflective cathode is not more than two-thirds of the total display area of the organic light-emitting display element, and the remaining one-third or more is light-transmissive. This is a light-emitting element, and has an effect that high-quality illumination light can be obtained.

According to a second aspect of the present invention, there is provided an organic light-emitting display device comprising a transparent substrate, a transparent electrode, an organic semiconductor layer including a light-emitting layer, and a light-reflective cathode formed in this order. The occupied area is a stacked display element including at least one organic light-emitting element, characterized in that the area is not more than two-thirds of the total display area of the organic light-emitting display element. Has the effect of high quality.

According to a third aspect of the present invention, the organic light emitting device is disposed on a different light emitting device, and display by the organic light emitting device and display by a different light emitting device are simultaneously observed. 2. The stacked display element according to item 2, which has a color, high-quality, and high-quality action.

According to a fourth aspect of the present invention, the organic light-emitting device is disposed on a reflective display medium, and the display on the reflective display medium is observed by light illuminated by the organic light-emitting device. A multi-layer display element according to claim 2, wherein the multi-layer display element has the function of high quality and high quality in color.

According to a fifth aspect of the present invention, there is provided the multilayer display device according to the second aspect, wherein the different light emitting elements are organic light emitting elements that emit different colors. It has the effect of high image quality and high quality.

According to a sixth aspect of the present invention, there is provided the multilayer display device according to the second aspect, wherein the organic light emitting element is an organic light emitting element that emits at least two colors. It has the effect of high image quality and high quality in color.

According to a seventh aspect of the present invention, there is provided an organic light-emitting display device comprising a transparent substrate, an organic semiconductor layer including a light-emitting layer, and a light-reflective cathode formed in this order on a transparent substrate. The occupied area is not more than two-thirds of the total display area of the organic light-emitting display element. It has the effect of high quality.

The invention according to claim 8 is characterized in that the two-layer stacked organic light-emitting device is arranged on different light-emitting devices, and display by the organic light-emitting device and display by a different light-emitting device are simultaneously observed. In this case, the display device has a color image quality and a high quality.

According to a ninth aspect of the present invention, there is provided the multi-layer display device according to the eighth aspect, wherein the different light emitting elements are organic light emitting elements, and each light emitting color is different. It has the effect of high image quality and high quality in color.

According to a tenth aspect of the present invention, the different light emitting element is a light emitting element other than the organic light emitting element, and each of the light emitting elements has a different emission color. Color, high quality in color,
Has the effect of high quality.

[0024]

Next, specific examples of the present invention will be described.

Example 1 Hereinafter, a light emitting device according to a first embodiment of the present invention will be described with reference to FIG.

In FIG. 1, reference numeral 1 denotes a glass substrate. On the surface thereof, a transparent anode 2 composed of indium tin oxide for injecting holes and a triphenyldiamine (triphenyldiamine) formed uniformly on the substrate surface on which the anode is formed TPD [N, N'-bis (3-methylphenyl)-(1,1'-b
iphenyl) -4,4'-diamine]), and a uniformly formed aluminum quinolinol complex (A
an electron-transporting organic light-emitting layer 4 made of lq [tris (8-hydroxyquino) aluminum]), and a width of 330 μm made of a laterally divided silver-magnesium alloy for injecting electrons.
A cathode layer 5 having a pitch of 1 mm and a thickness of 1 mm, and a silicon oxide layer 7 as a protective layer are formed on the surface of the cathode layer 5 in order. When an electric field is applied between the anode 2 and the cathode 5, holes and electrons are injected into the organic light emitting layer in a region where the horizontal and vertical electrodes intersect, and electroluminescence 8 is generated.

In this display, the windows 6 other than the cathode forming portion are almost light-transmitting, and most of the windows 6 (about 2/3 of the area) where the cathode is not formed transmit light 9 through the background. It is possible to exhibit a new function that can be observed as.

In this embodiment, a matrix type display is shown. However, the present invention is not limited to this. A metal electrode serving as a cathode is formed only in a segment for display as in the case of displaying characters and numerals. You should keep it. In this case, the portion where the numbers and characters are not displayed transmits light, so that the background can be similarly observed.

(Example 2) A light emitting device according to a second embodiment of the present invention will be described with reference to FIG.

In FIG. 2, reference numeral 21 denotes a glass substrate.
On its surface, a transparent anode 2 made of indium tin oxide for injecting holes, and triphenyldiamine (TP
D), a hole-transporting layer 23 composed of an aluminum quinolinol complex (Alq) and an organic light-emitting layer 24 having an electron-transporting property are uniformly formed, and furthermore, stripe-shaped silver divided in one direction for injecting electrons. 100μ width made of magnesium alloy
A cathode layer 25 having a pitch of 1 mm and a pitch of 1 mm, and a silicon oxide layer 27 as a protective layer are formed on the surface of the cathode layer 25 in order.

Reference numeral 28 denotes a printed normal paper surface. When an electric field is applied between the anode 22 and the cathode 25, illumination light 29 is radiated from a linear region in contact with the metal electrode of the light emitting layer, and reflected light 30 reflected on the surface of the paper forms a window on which no electrode is formed. Section, it is possible to observe information on the paper.

(Embodiment 3) In the above-described display, the configuration using the organic EL as the illumination light source for the printed matter has been described. However, the display is not necessarily limited to the printed matter, and may be a reflective display such as a liquid crystal display. An embodiment in this case will be described with reference to FIG. A light emitting device according to a third embodiment of the present invention will be described with reference to FIG. FIG.
In the figure, 31 is a glass substrate. On its surface, a transparent anode 3 made of indium tin oxide for injecting holes.
2. The organic layer 33, which is a hole transport layer and an electron transporting light emitting layer, is uniformly formed, and is made of a silver-magnesium alloy in a stripe shape divided in one direction for injecting electrons. , A cathode layer 35 having a pitch of 1 mm, a silicon oxide layer 27 as a protective layer uniformly over the surface thereof, and a resin layer are sequentially formed.

On the other hand, the transparent electrode 3
2 'is formed, and a liquid crystal layer 38 is inserted between the second glass substrate 31 on which the reflective electrode 39 is formed. The liquid crystal is displayed by applying an electric field to the liquid crystal. When an electric field is applied between the transparent anode 32 and the cathode 35, the illumination light 4
0 is emitted, and the light reflected by the front liquid crystal layer passes through a region where no electrode is formed as transmitted light 40 ', so that image information and the like formed on the liquid crystal element can be observed.

(Embodiment 4) In the above invention, a display having a new function has been described by making a part of a transmissive type by utilizing the features of the organic EL, but the light emitting element has a laminated structure. Accordingly, a full-color display can be formed.

Hereinafter, the light emitting device according to the first embodiment of the present invention will be described with reference to FIG.

In FIG. 4, reference numeral 411 denotes a first glass substrate. A transparent first anode 412 made of indium tin oxide for injecting holes and a hole uniformly formed on the surface of the substrate on which the anode is formed are linearly divided on the surface thereof. A first organic layer 413, which is a transport layer and an organic light emitting layer which emits green light which is also uniformly formed, and further has a width of 300 μm, a pitch of 1 mm, which is made of a vertically divided silver-magnesium alloy for injecting electrons. A cathode layer 414 and a silicon oxide layer 415 as a protective layer are further formed sequentially on the surface thereof.

Reference numeral 421 is a second glass substrate.
On its surface, a transparent second anode 422, which is divided linearly in the horizontal direction and is made of indium tin oxide for injecting holes.
And a second organic layer 423 comprising a hole transport layer and an organic light emitting layer which emits blue light which is uniformly formed on the substrate surface on which the anode is formed, and a second organic layer 423 for further injecting electrons. Width 3 made of silver-magnesium alloy divided vertically
A cathode layer 424 having a thickness of 00 μm and a pitch of 1 mm, and further a silicon oxide layer 425 as a protective layer are formed sequentially on the surface thereof.

Further, reference numeral 431 denotes a third glass substrate.
On its surface, a transparent third anode 432 divided in a lateral direction and made of indium tin oxide for injecting holes.
And a second organic layer 433, which is uniformly formed on the substrate surface on which the anode is formed, and is composed of a hole transport layer and an organic light emitting layer which emits blue light which is also uniformly formed, and further for injecting electrons. Width 33 made of silver-magnesium alloy divided vertically
A cathode layer 434 having a thickness of 0 μm and a pitch of 1 mm, and further a silicon oxide layer 435 as a protective layer are formed sequentially on the surface thereof.

The above three-layer light-emitting elements are arranged such that the area of the cathode portion is about 1/3 of the whole element and that they do not overlap.

When an electric field is applied between the first anode 412 and the first cathode 414, holes and electrons are injected into the organic light emitting layer in the region where the horizontal and vertical electrodes intersect, and green light is emitted. 441 occur and can be observed through the first transparent substrate 411.

The second anode 422 and the first cathode 424
When an electric field is applied between the electrodes, holes and electrons are injected into the organic light emitting layer in the region where the vertical and horizontal electrodes intersect, blue light emission 442 is generated, the second transparent substrate 421 and the green light emitting element Observable through.

The third anode 432 and the first cathode 434
When an electric field is applied between the electrodes, holes and electrons are injected into the organic light emitting layer in a region where the vertical and horizontal electrodes intersect, red light emission 443 is generated, the third transparent substrate 431 and blue light emission Observable through the device and the green light emitting device.

As described above, by causing each element to emit light independently, it is possible to independently control and emit green, blue and red light, and to obtain a color display.

In the above invention, the cathode portions of the three-layer organic EL element are each about 1/3, but if they do not overlap each other, the area of the cathode portions of the second and third layers is at most large. I can't tell.

(Embodiment 5) In the above invention, a three-layer organic EL element was used.
It is not necessary to use an L element, and a different light emitting element can be used as the lowermost layer. FIG. 5 shows a configuration of a color display using a red light emitting diode.

Hereinafter, a light emitting device according to a fifth embodiment of the present invention will be described with reference to FIG.

In FIG. 5, reference numeral 511 denotes a first glass substrate. A transparent first anode 512 made of indium tin oxide for injecting holes and a hole uniformly formed on the surface of the substrate on which the anode is formed are linearly divided on the surface thereof. A first organic layer 513 comprising a transport layer and an organic light emitting layer which emits green light which is also uniformly formed, and a width of 330 μm and a pitch of 1 mm comprising a vertically divided silver-magnesium alloy for injecting electrons. A cathode layer 514 and a silicon oxide layer 515 as a protective layer are further formed sequentially on the surface thereof.

521 is a second glass substrate.
On its surface, a transparent second anode 522, which is divided into horizontal lines and is made of indium tin oxide for injecting holes.
A second organic layer 523 composed of a hole transport layer and a similarly uniform organic light emitting layer emitting blue light, which are uniformly formed on the surface of the substrate on which the anode is formed, and further for injecting electrons. Width 3 made of silver-magnesium alloy divided vertically
A second cathode layer 524 having a thickness of 30 μm and a pitch of 1 mm, and a silicon oxide layer 525 as a second protective layer are formed sequentially on the surface thereof uniformly.

On the other hand, reference numeral 533 denotes a gallium arsenide substrate on which a PN junction is formed in the vertical direction by a gallium aluminum layer, and the surface is further covered with a protective film 531.

When an electric field is applied between the first anode 512 and the first cathode 514, holes and electrons are injected into the organic light emitting layer in the region where the horizontal and vertical electrodes intersect, and green light is emitted. 541 occur and can be observed through the first transparent substrate 511.

The second anode 522 and the first cathode 524
When an electric field is applied between the electrodes, holes and electrons are injected into the organic light emitting layer in the region where the vertical and horizontal electrodes intersect, blue light emission 542 is generated, and the second transparent substrate 521 and the green light emitting element Observable through.

When a current is injected into the third light emitting portion 532 formed on the third substrate, the red light emission 54
3, the third transparent substrate 431 and the blue light emitting element,
Observable through the green light emitting element.

By causing each element to emit light independently in this way, it is possible to independently control and emit green, blue and red light, and to obtain a color display.

By these methods, a full-color display can be realized by a new structure in which an organic EL that emits normal blue and green light and a red light-emitting diode array are stacked. A display that normally emits red light has a short operating life, which determines the reliability of the entire device. Therefore, a very reliable color display can be realized by this method.

(Embodiment 6) In the above embodiment, three layers of light emitting elements corresponding to each color are used, but it is not always necessary to use three layers. If it is possible to obtain two colors by one layer, it is also possible to display a full-color image with two layers of light emitting elements.

Hereinafter, a light emitting device according to a sixth embodiment of the present invention will be described with reference to FIG.

In FIG. 6, reference numeral 611 denotes a first glass substrate. The surface is divided vertically to a width of 330 μm,
A color conversion layer 616 having a shape with a pitch of 1 mm and converting green to red is formed. Further, a transparent first anode 612 made of indium tin oxide for injecting holes and a hole uniformly formed on the surface of the substrate on which the anode is formed is further divided into linear lines in the vertical direction on the surface thereof. A first organic layer 613 composed of a transport layer and an organic light-emitting layer uniformly emitting blue light similarly formed, and a width of 330 μm and a pitch of 1 m composed of a vertically divided silver-magnesium alloy for injecting electrons.
The m-type cathode layer 614 and a silicon oxide layer 615 as a protective layer are further formed on the surface thereof uniformly. Here, the color conversion layer 616 is arranged so as not to overlap the first cathode.

Reference numeral 621 denotes a second glass substrate.
A transparent second anode 622 made of indium tin oxide for injecting holes is formed on the surface thereof in a laterally linear manner.
A second organic layer 623 composed of a hole transport layer and an organic light emitting layer which emits green light which is uniformly formed on the surface of the substrate on which the anode and the anode are formed, and further for injecting electrons. Width 3 made of silver-magnesium alloy divided vertically
A second cathode layer 624 having a thickness of 30 μm and a pitch of 1 mm, and a third cathode layer 625 having a similar shape are formed adjacent thereto. Further, a silicon oxide layer 626 as a second protective layer is sequentially formed on the entire surface.

When an electric field is applied between the first anode 612 and the first cathode 614, holes and electrons are injected into the organic light emitting layer in the region where the horizontal and vertical electrodes intersect, and blue light is emitted. 641 occur and can be observed through the first transparent substrate 611.

The second anode 622 and the second cathode 624
When an electric field is applied between the electrodes, holes and electrons are injected into the organic light emitting layer in the region where the horizontal and vertical electrodes intersect, and green light is emitted, which is further converted to red by the color conversion element. Observed. Also, the second anode 622 and the third
When an electric field is applied between the negative and positive electrodes 624, holes and electrons are injected into the organic light emitting layer in the region where the vertical and horizontal electrodes intersect, green light is emitted and passes through the first light emitting element. Observed.

(Example 7) Hereinafter, a light emitting device according to a seventh embodiment of the present invention will be described with reference to FIG.

In FIG. 7, reference numeral 711 denotes a first glass substrate. The surface is divided vertically to a width of 330 μm,
A color conversion layer 716 having a 1 mm pitch and converting blue to green is formed. Further, a transparent first anode 712 made of indium tin oxide for injecting holes and a hole uniformly formed on the surface of the substrate on which the anode is formed are further divided into linear lines in the lateral direction on the surface thereof. A first organic layer 713 comprising a transport layer and an organic light emitting layer which emits blue light which is also uniformly formed, and a width 330 μm and a pitch 1 m comprising a vertically divided silver-magnesium alloy for injecting electrons.
m first cathode layer 714 and a second cathode layer 715 having a similar shape are formed adjacent thereto. Further, a silicon oxide layer 716 as a protective layer is sequentially formed on the entire surface. Here, the color conversion layer 616 is arranged so as not to overlap the first cathode. On the other hand, 723
Is a gallium arsenide substrate, on the surface of which a gallium aluminum layer forms a light emitting portion 722 with a PN junction in the lateral direction, and the surface is further covered with a protective film 721.

When an electric field is applied between the first anode 712 and the first cathode 714, holes and electrons are injected into the organic light emitting layer in the region where the vertical and horizontal electrodes intersect, and blue light is emitted. 741, which can be observed through the first transparent substrate 711, which is converted to green by the color conversion element and observed. A first anode 712 and a second cathode 715
When an electric field is applied between the electrodes, holes and electrons are injected into the organic light emitting layer in the region where the vertical and horizontal electrodes intersect, and blue light is emitted.

Further, when a current is injected into the third light emitting portion 722 formed on the third substrate, the red light emission 74
2, and red can be observed through the first transparent substrate 711. By causing each element to emit light independently in this manner, green, blue, and red light can be controlled and emitted independently, and a color display can be obtained.

By these methods, a full-color display can be realized by a new configuration in which an organic EL that emits normal blue and green light and a red light-emitting diode array are stacked. A display that normally emits red light has a short operating life, which determines the reliability of the entire device. Therefore, a very reliable color display can be realized by this method.

[0066]

As described above with reference to the embodiments, in the present invention, a light emitting device and a color device having a relatively simple device structure and high reliability can be obtained without taking complicated structures and processes as in the prior art. It is possible to realize a display element.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a light emitting device according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a light emitting device according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view of a light emitting device according to a third embodiment of the present invention.

FIG. 4 is a sectional view of a light emitting device according to a fourth embodiment of the present invention.

FIG. 5 is a sectional view of a light emitting device according to a fifth embodiment of the present invention.

FIG. 6 is a sectional view of a light emitting device according to a sixth embodiment of the present invention.

FIG. 7 is a sectional view of a light emitting device according to a seventh embodiment of the present invention.

FIG. 8 is a schematic structural diagram of a conventional organic light emitting device.

[Explanation of symbols]

 1, 21, 31, 31 ′ Glass substrate 2, 22, 32, 32 ′ Transparent electrode 3, 23, Hole transport layer 4, 24 Light emitting layer 5, 25, 35 Cathode layer 6, 26, 36 Window 7, 27 , 37 Protective layer 8, 29, 40 Electroluminescence 9, 30, 40 'Transmitted light 28 Paper surface 33 Organic layer 38 Liquid crystal layer 39 Reflective electrode 411, 511 First transparent substrate 412, 512 First transparent electrode 413, 513 First organic Layer 414, 514 First cathode 415, 515 First protective layer 421, 521 Second transparent substrate 422, 522 Second transparent electrode 423, 523 Second organic layer 424, 524 Second cathode 425, 525 Second protective layer 431, 531 Third transparent substrate 432, 532 Third transparent electrode 433, 533 Third organic layer 434, 534 Third cathode 435, 535 Third protective layer 441, 541 Green light emission 4 42, 542 Blue light emission 443, 543 Red light emission 611 First transparent substrate 612 First transparent electrode 613 First organic layer 614 First cathode 615 First protective layer 616 Color conversion layer 621 Second transparent substrate 622 Second transparent electrode 623 2 organic layers 624 2nd cathode 625 3rd cathode 626 2nd protective layer 641 blue luminescence 642 green luminescence 643 red luminescence 711 1st transparent substrate 712 1st transparent electrode 713 1st organic layer 714 1st cathode 715 2nd cathode 716 1 protective layer 721 second protective layer 722 third light emitting layer 723 semiconductor substrate 741 blue light emitting layer 742 red light emitting layer 743 green light emitting layer

Claims (10)

[Claims] 1. An organic light-emitting display device comprising a transparent electrode, an organic semiconductor layer including a light-emitting layer, and a light-reflecting cathode formed in this order on a transparent substrate. A light-emitting element which is less than two-thirds of the total display area of the display element, and the remaining one-third or more is light-transmitting. 2. An organic light-emitting display device comprising a transparent substrate, a transparent electrode, an organic semiconductor layer including a light-emitting layer, and a light-reflecting cathode, which are sequentially formed on a transparent substrate. A multi-layer display element comprising at least one organic light-emitting element, wherein the display element is two-thirds or less of the total display area of the display element. 3. The multi-layer display device according to claim 2, wherein the organic light-emitting elements are arranged on different light-emitting elements, and display by the organic light-emitting elements and display by different light-emitting elements are simultaneously observed. 4. An organic light-emitting device is disposed on a reflective display medium, and is illuminated by the organic light-emitting device.
3. The multi-layer display device according to claim 2, wherein a display of the reflective display medium is observed. 5. The multi-layer display device according to claim 2, wherein the different light emitting elements are organic light emitting elements that emit different colors. 6. The multi-layer display device according to claim 2, wherein the organic light emitting device is an organic light emitting device that emits at least two colors. 7. An organic light-emitting display device comprising a transparent substrate, a transparent electrode, an organic semiconductor layer including a light-emitting layer, and a light-reflecting cathode, which are sequentially formed on a transparent substrate. A multilayer display element comprising at least two organic light-emitting elements, wherein the total display area of the display element is two-thirds or less. 8. The organic light-emitting device according to claim 7, wherein two stacked organic light-emitting devices are arranged on different light-emitting devices, and display by the organic light-emitting device and display by a different light-emitting device are simultaneously observed. Multilayer display element. 9. The different light emitting device is an organic light emitting device.
9. The multi-layer display device according to claim 8, wherein the light emission colors are different from each other. 10. The multi-layer display element according to claim 8, wherein the different light-emitting elements are light-emitting elements other than the organic light-emitting element, and have different emission colors.