KR101768472B1 - Display Panel and Method for Manufacturing the Same - Google Patents

Abstract

The present invention relates to a display panel that controls an optical field to modulate and emit light emitted from a light source so as to have a high optical efficiency and a fast response speed, and a method of manufacturing the same. The display panel of the present invention includes a plurality of pixels A non-display area defined on an outer periphery of the pixel; a light coupler formed on a non-display area of the substrate and adapted to receive light incident from the outside and enter the substrate; A plurality of pixel elements formed on each of the pixels on the substrate and adapted to emit light by modulating an optical field; And an optical switch array connected to the optical coupler and receiving the incident light to switch the light to the pixel device side and transmit the switched light.

Description

DISPLAY PANEL AND METHOD FOR MANUFACTURING THE SAME

The present invention relates to a display panel, and more particularly, to a display panel that controls an optical field to modulate and emit light emitted from a light source so as to have a high light efficiency and a fast response speed, and a method of manufacturing the same.

In the information society, display has become more important as a visual information delivery medium, and it is necessary to meet requirements such as low power consumption, thinning, light weight, and high image quality in order to take a major position in the future.

Such a display may include a cathode ray tube (CRT), an electroluminescence (EL), a light emitting diode (LED), a vacuum fluorescent display (VFD) A light emitting type such as a field emission display (FED), a plasma display panel (PDP) or the like, and a non-light emitting type such as a liquid crystal display (LCD) .

In recent years, the display has not been limited to the above-described method, but research of a new display has been actively pursued for higher image quality and faster response speed as the user's desire increases.

For example, a typical display device will be described as follows.

2. Description of the Related Art A general liquid crystal display (LCD) device is a display device capable of displaying a desired image by individually supplying image signals to pixels arranged in a matrix form and controlling light transmittance of the pixels. To this end, the liquid crystal display device has a structure in which a lower substrate on which thin film transistors are arranged and an upper substrate on which color filters are formed are bonded together with the liquid crystal layer interposed therebetween. In addition, a polarizing plate is formed on the surfaces of the lower substrate and the upper substrate, respectively, to control blocking or transmission along the transmission direction. The liquid crystal display device has a backlight unit at a lower portion thereof, and the light emitted from the backlight unit is emitted from the liquid crystal layer in accordance with application of an electric field by the thin film transistor.

Such a liquid crystal display device has a color filter for displaying hue, and has a low light transmittance and a low efficiency of about 5%. Particularly, as the white light passing through the backlight unit passes through the R, G, and B color filters transmitting only one color, the light efficiency thereof is reduced by about 66%, and the efficiency by 50% , Which is a major cause of decreasing the light efficiency of the entire display.

Further, the response speed is determined according to the orientation change of the liquid crystal depending on the application of the electric field, and has a relatively low response speed in comparison with other displays.

Further, by using the light of the backlight unit, it has a relatively low contrast ratio in comparison with the self-luminous display.

Further, as shown in the figure, since it is provided with various components such as a thin film transistor, a color filter, a liquid crystal layer, and a polarizing plate, it has a complicated structure and has to be subjected to various manufacturing steps, which complicates the process.

A general organic light emitting device includes a light emitting layer for emitting light between the anode and the cathode, an anode and a cathode opposed to each other on the substrate, a hole injection layer, a hole transport layer, And an electron transport layer and an electron injection layer sequentially formed between the light emitting layer and the cathode.

Such an organic light emitting element is made of an organic material which is liable to be deteriorated by moisture and has a difficulty in complete sealing and the like. In addition, in the shadow mask process used for forming a light emitting layer for each pixel, problems such as clogging, It is difficult to form a large-area panel.

Further, since the luminescent characteristics vary depending on the conditions of the light emitting layer and its surrounding layers, there is a limitation in selecting the material thereof, and there is a problem that the manufacturing cost of the display of the same size is high.

Further, the degradation rates of the light emitting materials forming the light emitting layers of different colors are different, and there is a problem that the color change occurs during the long driving.

In addition, it is necessary to match the HOMO and LUMO energy levels of the electrodes and the surrounding layers and the light emitting layers to the adjacent layers, and electrode materials having a work function suited to each energy level are required.

The organic electroluminescent device and the liquid crystal display device, which have recently been spotlighted, suffer from the following problems.

That is, the organic light emitting element can not avoid the problem of element deterioration and can not be driven for a long time according to the use of organic materials. Further, in the process of depositing a light emitting layer using a shadow mask, there are problems such as clogging and shattering of a shadow, and it is difficult to manufacture a large-sized panel. Further, electrons or holes can be transported depending on the HOMO and LUMO energies in the luminescent material and its surrounding layer, or the transportation efficiency is high, which makes it difficult to select materials.

In other liquid crystal display devices, a color filter is used for color implementation, and the aperture ratio is lowered due to formation of thin film transistors and other wirings by electric field driving of the liquid crystal, and the light efficiency is as low as about 5%. In addition, since the response speed of the liquid crystal is slow, it is difficult to obtain a fast response speed. Further, depending on the provision of the thin-film transistor, the color filter, the liquid crystal layer, and the polarizing plate, the process is complicated.

Disclosure of Invention Technical Problem [8] The present invention has been devised to solve the above-mentioned problems, and it is an object of the present invention to provide a display panel in which light emitted from a light source is modulated by controlling an optical field so as to have a high light effect and a fast response speed It has its purpose.

According to an aspect of the present invention, there is provided a display panel including a substrate having a plurality of pixels defined in a matrix at a center thereof and defining a non-display region on an outer periphery of the pixel; A plurality of pixel elements formed on each of the plurality of pixels and adapted to emit light by modulating an optical field on the substrate; And an optical switch array connected to the optical coupler and receiving the incident light to switch the light to the pixel device side and transmit the switched light.

The optical switch array includes a backbone waveguide connected to the optocoupler in the non-display area, the backbone waveguide having the incident light traveling in one direction, A plurality of pixel line waveguides arranged in a direction intersecting with the base light waveguide; and a plurality of pixel line optical waveguides formed between the base optical waveguide and the pixel line optical waveguides, And an optical switch for outputting the output signal.

A first optical waveguide formed on the common electrode and extending from the pixel line optical waveguide to pass the pixels; and a second optical waveguide formed on the second optical waveguide, A gate electrode formed on the refractive index variable layer in a row direction; And a color conversion material formed for each pixel on the gate electrode.

The light source may further include a light source for introducing light into the optical coupler.

The optical coupler is a second optical waveguide that receives the incident light and transmits the received light to the base optical waveguide.

The optical coupler may be implemented by forming a grating on the surface of the second optical waveguide through which the incident light enters. Alternatively, the optical coupler may be implemented by providing a prism on the surface of the second optical waveguide through which the incident light enters. Alternatively, in the optical coupler, the second optical waveguide through which the incident light enters may be implemented by attaching a taper having a shape narrowing to the base optical waveguide from the incident portion of the incident light.

In addition, a data driver may be further provided in a non-display area of the substrate adjacent to the optical switches. Here, the data driver is connected to a data connection wiring formed on the optical switch. In this case, the amount of light applied to the connected pixel line optical waveguide can be adjusted according to the voltage value applied to the data connection wiring formed on the optical switch.

And a gate driver connected to the gate electrode on the other side of the non-display region on the substrate.

The common electrode and the gate electrode are transparent electrodes.

Here, 0V or a constant voltage is applied to the common electrode, and the same gate-on voltage is sequentially applied from the upper side to the lower side or from the lower side to the upper side to the gate electrode sequentially.

On the other hand, the color conversion material is a light-emitting layer of a down-conversion material. The downconversion material is a photo-luminescence material. For example, the downconversion material may be a fluorescent material or a phosphorescent material.

In addition, the refractive index-variable layer has a refractive index that varies electro-optically.

The first optical waveguide, the second optical waveguide, the base optical waveguide, and the pixel line optical waveguide may include a cladding layer and a core layer, respectively. Here, the first optical waveguide, the second optical waveguide, the base optical waveguide, and the pixel line optical waveguide may share the cladding layers, and the respective core layers may be separately patterned.

The refractive index of each core layer is larger than the refractive index of each of the clad layers.

Meanwhile, the optical switch may be a directional coupler device or a multimode interference (MMI) device.

When the electric field is formed between the common electrode and the gate electrode, the pixel elements change the refractive index of the refractive index variable layer to modulate the optical field of the light transmitted to the pixel line optical waveguide, So that the tail is transferred to the color conversion material.

According to another aspect of the present invention, there is provided a method of manufacturing a display panel, including: preparing a substrate having a plurality of pixels defined in a matrix at a center thereof and defining a non- Forming a common electrode and a cladding layer on a substrate; forming a common electrode and a cladding layer on the substrate; forming a common electrode and a cladding layer on the substrate; Forming a first core layer on the pixels, the first core layer extending in a direction in which the pixel line core layer and the pixel line core layer extend in an intersecting direction; Forming a refractive index variable layer on the cladding layer including the first core layer; forming a gate electrode on the refractive index variable layer so as to pass through pixels in the horizontal direction; And forming a color conversion material corresponding to each pixel on the gate electrode.

The method may further include forming a data connection wiring on the refractive index variable layer corresponding to the gap between the adjacent base core layer and the pixel line core layer.

The method may further include forming a gate connection wiring connected to the gate electrodes in the non-display region.

The method may further include forming a data driver connected to the data connection wiring and a gate driver connected to the gate connection wiring.

The display panel of the present invention and its manufacturing method as described above have the following effects.

First, since the degree of freedom in selecting the luminescent material used for the color conversion material is high, it is possible to realize a display having a high light efficiency and a high color number depending on the selected luminescent material, a display having a high pixel response speed and a high contrast ratio Pixel implementation is possible.

Secondly, since all elements for modulating the optical field such as an optical coupler, an optical switch, and a pixel element are integrated on a single glass substrate, the panel structure is simple, and a manufacturing process can be performed with a simple process.

Third, it is possible to create various applications of transparent display using transparency of display panel.

Fourth, light emission is possible by optical field modulation or switching, and the light efficiency is not affected by the aperture ratio of the panel, and there is no absorption of light by the color filter. Further, since the energy due to the optical field modulates the refractive index, the light energy is transmitted to the light emitting layer, so there is no decrease in the light efficiency.

Fifth, a luminescent material having a low degree of deterioration by the environment can be freely selected by a photo-luminescence method. In the case of other electroluminescent devices, not only the luminescent material but also the electrode material for supplying electric charges should be selected in consideration of the electron energy level, and deterioration of the electrode material is also a factor that affects the performance of the entire luminescent device. For example, in the case of an organic electroluminescent device, since the light emitting layer and the conductive layer are composed of organic materials, deterioration of the device due to moisture becomes a big issue. In addition, in the case of a quantum dot light emitting device, However, in many cases, since the organic electrode material is used to increase the efficiency, deterioration by moisture can not be avoided.

Sixth, the display having the optical field modulated light emitting device of the present invention has a wide viewing angle because each pixel is driven by the self-luminous self-emitting light.

1 is a plan view showing a display panel according to the present invention;
Fig. 2 is a perspective view of Fig.
3 is a plan view showing the optical coupler of FIG.
Fig. 4 is a perspective view showing the light traveling direction of the optocoupler portion in Fig.
5 is a cross-sectional view showing an optical coupler according to the first embodiment of the display panel of the present invention
6 is a cross-sectional view showing an optical coupler according to a second embodiment of the display panel of the present invention
7 is a perspective view illustrating an optical coupler according to a third embodiment of the display panel of the present invention.
Fig. 8 is a plan view showing the optical switch of Fig. 2 and a graph
9 is a perspective view showing an optical switch according to another embodiment of the present invention.
10 is a perspective view showing a connection portion of the optical switch and the pixel element of the display panel of the present invention
11 is a cross-sectional view showing an optical field at the time of light emission and non-light emission of the pixel element of the present invention
Figs. 12A and 12B are graphs showing optical elements before and after optical field modulation of the pixel element of the present invention
FIG. 13 is a graph showing the abscissa field tail profile before and after optical field modulation of the pixel element of the present invention
14A to 14G are process perspective views of a display panel according to the present invention

Hereinafter, a display panel and a method of manufacturing the same according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a plan view of a display panel according to the present invention, and FIG. 2 is a perspective view of FIG.

1 and 2, a display panel according to an embodiment of the present invention includes a substrate 100 having a plurality of pixels defined in a matrix at a center thereof and a non-display area defined on an outer periphery of the pixels, A light coupler 400 formed in a non-display area for receiving and exciting light incident from the outside, and a plurality of light emitting elements (not shown) formed on the substrate 100 for emitting light by modulating the optical field And an optical switch array (300) connected to the optical coupler (400) for receiving the excited light and switching it to the pixel device side for transmission, and an optical switch array . Here, the optical coupler 400 allows external light to enter the optical waveguide (connected to the optical switch array) formed on the substrate 100.

The optical switch array 300 includes a backbone waveguide 200 connected to the optical coupler 400 and traveling in one direction to the excited light in the non-display region, A plurality of pixel line waveguides 250 disposed in a direction crossing the base optical waveguide toward the pixels and a plurality of pixel line waveguides 250 disposed between the base optical waveguide 220 and the pixel line optical waveguides And an optical switch for outputting the excited light to the pixel line optical waveguide.

The pixel element array 500 includes a common electrode (refer to 105 in FIG. 10) formed on the front surface of the substrate 100 and a common electrode (See FIG. 10) formed on the first optical waveguide 250a and a second optical waveguide 250b extending on the first and second optical waveguides 250a and 250b, a gate electrode 120 formed in a row direction and a color conversion material 190 formed for each pixel on the gate electrode 120.

The common electrode 105 and the gate electrode 120 are transparent electrodes and the first optical waveguide 250a and the refractive index variable layer 160 are transparent materials capable of transmitting light.

When the electric field is formed between the lower common electrode 105 and the upper gate electrode 120, the refractive index variable layer 160 has a refractive index that is electro-optically variable. Modulates the optical field of light transmitted to the first optical waveguide 250a by changing the index of refraction of the first optical waveguide 160 so that the modulated optical field tail is transmitted to the color conversion material 190.

In addition, the color conversion material 190 is a material that is photo-luminescible according to a refractive index change of the lower refractive index variable layer 160. For example, a light-emitting layer of a down-conversion material. The downconversion material is a photo-luminescence material. The downconversion material may be a fluorescent material or a phosphorescent material.

On the other hand, an electric field between the common electrode 105 and the gate electrode 120 is 0V or a constant voltage is applied to the common electrode 105 and the gate electrode 120 is applied from the upper side to the lower side And the same gate-on voltage is sequentially applied from the lower side to the upper side. At this time, the gate-on voltage and the phase voltage applied to the common electrode 105 have different values. As the difference value becomes larger, a strong electric field is formed.

The data driver 600 may further include a non-display area of the substrate adjacent to the optical switches. Here, the data driver 600 is connected to the data connection wiring 305 formed on the optical switch 300. In this case, the amount of light applied to the connected pixel line optical waveguide 250 can be adjusted according to the voltage value applied to each data connection wiring 305 formed on the optical switch 300.

The gate driver 120 may further include a gate driver 650 connected to the gate electrode 120 on the other side of the non-display region on the substrate 100 where the data driver 600 is not formed. On voltage is applied to the gate electrode 120 side via the gate connection wiring line 125. In addition,

Meanwhile, the display panel of the present invention may further include a light source that allows light to be incident on the optical coupler 400.

The optical coupler 400 is a second optical waveguide (400a, 400b, 400c in FIGS. 5 to 7) for receiving the incident light and transmitting the received light to the base optical waveguide.

The first optical waveguide 250a, the second optical waveguides 400a, 400b and 400c, the base optical waveguide 200 and the pixel line optical waveguide 250 are formed of a clad layer and a core layer ). The first optical waveguide 250a, the second optical waveguides 400a, 400b, and 400c, the base optical waveguide 200, and the pixel line optical waveguide 250 may share the clad layers for simplification of processes. And each of the core layers is patterned by being separated from each other. In this case, the cladding layer includes the substrate 100 and has a first refractive index formed on the entire surface of the substrate 100. The core layer is a material having a relatively higher refractive index than the cladding layer.

The light incident from the optical coupler 400 is transmitted from the optical coupler 400 to the base optical waveguide 200 and a predetermined amount of light of the switched portion is incident on the pixel line optical waveguide 200 250). The amount of light transmitted from the pixel line optical waveguide 250 is determined by optical field modulation of the refractive index conversion layer 160 of the pixel according to whether the voltage of the gate electrode 120 on the first optical waveguide 250a is applied And the color conversion material 190 emits light.

Hereinafter, each configuration will be described in detail with reference to the drawings.

FIG. 3 is a plan view of the optical coupler of FIG. 2, and FIG. 4 is a perspective view of the optical path of the optical coupler of FIG.

As shown in FIGS. 3 and 4, the optical coupler 400 of the display panel of the present invention is provided with projections and depressions 410 on the side where light is incident from an external light source.

Accordingly, the incident light traveling in the medium such as the air is refracted while being confronted with the unevenness 410 provided in the optical coupler 400, and is bent in the other direction to change its direction of travel to the inside of the optical coupler 400 . That is, by changing the momentum of the light wave, light is coupled to the second light waveguide.

Here, the layer having the irregularities 410 is preferably a core layer made of a material having a refractive index higher than that of the air.

Here, the incident portion through which the incident light enters is not limited to the above-described concave and convex, but may be a structure having a triangular prism or a taper attached thereto. The core layer is patterned in such a manner that the side where the excited light is incident from the incident portion becomes narrower, and the side having a narrow width is brought into contact with the base optical waveguide 200.

5 is a cross-sectional view illustrating an optical coupler according to a first embodiment of the display panel of the present invention.

5, a grating type waveguide light coupler 400a according to a first embodiment of the present invention is a grating type waveguide light coupler 400a having a refractive index higher than that of the substrate 100 on a substrate 100 The optical waveguide is formed in the laminated structure of the core layer 1110 in the form of a waveguide (the second optical waveguide described above) with a structure having the projections and depressions 410 corresponding to the incident side of the incident light.

Here, the substrate 100 is used as a clad layer, and a separate clad layer may be further provided between the substrate 100 and the core layer 1110. In any case, the refractive index of the core layer 1110 is made larger than that of the clad layer.

6 is a cross-sectional view illustrating an optical coupler according to a second embodiment of the display panel of the present invention.

6, the optical coupler 400b according to the second embodiment of the display panel of the present invention is a prism-type optical waveguide coupler, in which a core layer 1112 is formed on a substrate 100, And a prism 425 is further provided.

Here, the substrate 100 is used as a clad layer, and a separate clad layer may be further provided between the substrate 100 and the core layer 1112.

In this case, the prism 425 may further include an adhesive layer (not shown) on the light incidence side of the surface of the core layer 1112. For example, the spacing distance between the core layer 1112 and the prism 425 in the illustrated drawing may be the thickness of the adhesive layer.

Here, the refractive index of the prism 425 is higher than that of the core layer 1112. Then, incident light enters the hypotenuse of the prism 425 in a vertical direction.

7 is a perspective view illustrating an optical coupler according to a third embodiment of the display panel of the present invention.

7, the optical coupler according to the third embodiment of the display panel of the present invention is a tapered optical waveguide coupler 400c, and a core layer 1112 is formed on a substrate (not shown, A taper 1113 having a shape gradually narrowing from an incident portion to a connecting portion of the base waveguide at an incident side and a triangular column 1114 having a shape for converging incident light on the upper side of the taper 1113. That is, the core layer 1112 is patterned on the substrate. Similarly, in the case of the third embodiment, a separate clad layer may be further provided between the substrate 100 and the core layer 1112, or the substrate 100 may be used as a clad layer.

Fig. 8 is a top view of the optical switch of Fig. 2 and a graph showing the optical field movement thereof. Fig.

As shown in Fig. 8, the optical switch 300 of the display panel of the present invention is defined, for example, as a directional coupler type between two adjacent optical waveguides. That is, the optical waveguide 200 includes a base optical waveguide 200 that advances in one direction, and a pixel line optical waveguide 250 that is adjacent to the base optical waveguide 200 in a predetermined region and that travels in a direction intersecting the base optical waveguide 200.

Although not shown, a common electrode (see 105 in FIG. 10) is further provided below the base optical waveguide 200 and the pixel line optical waveguide 250. The base waveguide 200 and the pixel line optical waveguide 250, a refractive index variable layer and a data connection wiring (see 305 in FIG. 2) are further provided. Accordingly, when the refractive index of the variable-refractive-index layer changes during the formation of an electric field between the data connection wiring 305 and the common electrode 105, the refractive index of the variable-refractive-index layer is changed between the optical waveguide 200 and the pixel- The phenomenon that the optical field is transferred occurs. That is, as shown in FIG. 8, light incident on the base light pipe 200 is transferred to the pixel line light pipe 250, and as a result, light can be transmitted to the pixel through the pixel line light pipe 250 It is. Here, the amount of light to be switched by the optical switch 300 is adjusted by adjusting the electric field strength between the data connection wiring 305 and the common electrode 105.

The optical path of the light incident on the optical switch 300 through the input port of the optical switch 300 is determined according to the conditions of the refractive index variable layer and the data connection wiring 305 on the optical switch 300 .

Here, the optical switch 300 has three ports, one of which is an input port of one side of the base optical waveguide 200, and the other is an input port of the base waveguide 200 The output port to the next optical switch on the other side, and the output port to pixel.

The cores of the adjacent base light waveguide 200 and the pixel line light waveguide 250 are designed to advance an eigen mode having wave vectors of similar size, To be switched to the core.

9 is a perspective view showing an optical switch according to another embodiment of the present invention.

9, an optical switch according to another embodiment of the present invention includes a first core layer 820 formed on a substrate 100 in a MMI (Multimode Interference) type, a first core layer 820 formed on the first core layer 820, A switching area patterned in a large area with a length L and a width W on the layer, an output port to the next optical switch, an output port to the pixel to pixel of the second core layer 821 protruding from the switching region. Here, the first core layer 820 and the second core layer 821 are integrally formed and made of the same material.

Compared with the directional optical switch described above with reference to Fig. 8, the MMI type optical switch has a structure in which light travels in the direction of the light diffracted at the patterned edge or port of the core layer, . Accordingly, the traveling direction of the light can be determined according to the shape of the second core layer 821. In addition, like the directional optical switch described above, the amount of light can be adjusted on the basis of conditions of the refractive index variable layer and the data connection wiring.

As described above, the ratio of light energy can be continuously distributed to 0 to 100% and transmitted according to the pattern shape of the optical switch, the refractive index variable layer on the optical switch, and the conditions of the data connection wiring.

10 is a perspective view showing a connection portion of an optical switch and a pixel element of a display panel of the present invention.

The connection of the optical switch and the pixel element of the display panel of the present invention will be described below in a layered form.

That is, a common electrode 105 formed on the front surface of the substrate 100, a common electrode 105 formed on the common electrode 105, extending from the pixel line optical waveguide 250, passing through the pixels, A refractive index variable layer 160 formed on the first optical waveguide 250a and a refractive index variable layer 160 formed on the refractive index variable layer 160. The first optical waveguide 250a, And a color conversion material 190 formed for each pixel on the gate electrode 120 and the gate electrode 120.

A pixel line optical waveguide 250 connected to the first optical waveguide 250a and a pixel line optical waveguide 250 adjacent to the pixel line optical waveguide 250 are formed on the same layer as the first optical waveguide 250a, A base optical waveguide 200 and an optical coupler 400 connected to one side of the optical waveguide 200 are formed together.

The first optical waveguide 250a, the base optical waveguide 200, the pixel line optical waveguide 250 and the optical coupler 400 each have a cladding layer 110 formed on the entire surface of the common electrode 105, And a core layer 130 on which an upper part of the surface is partially patterned.

11 is a cross-sectional view showing an optical field in a pixel element of the present invention at the time of light emission and non-light emission.

Referring to Fig. 11, the optical field in the light emission and non-light emission of the pixel element of the present invention will be described.

No electric field is formed between the common electrode 105 and the gate electrode 120 and no energy is transferred from the refractive index variable layer 160 to the color conversion material 190. Accordingly, the light continues to travel in the traveling direction of the pixel line optical waveguide without movement of the optical field traveling in the pixel line optical waveguide 250 (including 110 and 130).

At the time of light emission, an electric field is formed between the common electrode 105 and the gate electrode 120, and the refractive index value of the refractive index variable layer 160 is determined according to the electric field, and the refractive index becomes larger than a certain value. As the refractive index increases, the energy from the refractive index variable layer 160 to the color conversion material 190 is transferred to the optical field, and the color conversion material 190 is excited to emit light do.

12A and 12B are graphs showing the optical element before and after optical field modulation of the pixel element of the present invention.

Referring to FIG. 12B, when no voltage is applied or when a voltage to be applied is low, the center of the optical field is maintained in the core through which the light of the emitted light source is guided, The refractive index of the refractive index variable layer 160 on the core layer 130 of the optical waveguide is increased so that the center of the optical field moves upward and the optical tail gradually expands, (190). ≪ / RTI >

FIG. 13 is a graph showing an EEV field tail profile before and after optical field modulation of a pixel element of the present invention. FIG.

As shown in Fig. 13, the profile of the optical mode of the optical field modulated light emitting device of the present invention is shown. The graph represented by the rectangular points shows a state in which the refractive index of the refractive index variable layer has a low refractive index. And the variable layers are converted to show a high refractive index. The upper and lower electric field off and on states of the optical waveguide are shown, respectively.

It can be seen that the width of the optical field tail of the optical field is extended when the refractive index of the refractive index variable layer on the upper side of the optical waveguide is adjusted through the common electrode under the optical waveguide and the gate electrode on the upper side or the data connection wiring And it can be seen that the light emitting layer adjacent to the refractive index variable layer can emit light.

In this case, from the simulation results, it can be seen that the contrast ratio is 2,000,000: 1 when forming the display using the optical field modulated light emitting device of the present invention, and is considerably higher than other displays.

Hereinafter, the process of the display panel of the present invention will be described with reference to the drawings.

14A to 14G are process perspective views of a display panel according to the present invention.

In the method of manufacturing a display panel of the present invention, a plurality of pixels are defined as a matrix at the center and a non-display area is defined at the outer periphery of the pixel, as shown in FIG. 14A.

Next, a transparent common electrode 105 and a cladding layer 110 are formed on the entire surface of the substrate 100.

14B, a front core layer 130 is formed in a non-display region of the substrate, and a part of the surface of the front core layer 130 is patterned to form an optical coupler core layer 130a and the optical coupler core layer 130a. And extends in the direction in which the pixel line core layer 130c and the pixel line core layer 130c extend in a direction that is adjacent to and intersects with the base core layer 130b A first core layer 130d is formed on the pixels to form an optical coupler 400, a base optical waveguide 200, a pixel line optical waveguide 250, and a first optical waveguide 250a.

14c, a refractive index-variable layer (refractive index-variable layer) 210 is formed on the clad layer 110 including the optical coupler 400, the base light waveguide 200, the pixel line optical waveguide 250 and the first optical waveguide 250a 160 are formed.

14D, the transparent electrode is patterned on the refractive index variable layer 160 to form the gate electrode 120 so as to pass through the pixels in the horizontal direction.

Next, as shown in FIG. 14E, a color conversion material 190 is formed corresponding to each pixel on the gate electrode 120.

The data connection wiring 305 and the gate electrodes 120 are connected to the refractive index variable layer 160 between the adjacent base optical waveguide 200 and the pixel line optical waveguide 250, A gate connection wiring 205 is formed in the non-display region.

14F, a data driver 600 connected to the data connection wiring 305 and a gate driver 650 connected to the gate connection wiring 205 are formed.

As described above, the main components of the display panel of the present invention are an optical coupler (light coupler), an optical switch element, and a pixel element, which are integrated on a single substrate.

The structure of such a display panel is divided into a backbone waveguide connected to a light coupler, an optical switch array connected to the base optical waveguide and a respective optical switch, Outgoing pixel line optical waveguide. The pixel elements are formed in a matrix shape along the pixel line optical waveguide.

The operation of the display panel starts with the light from the light source outside the substrate entering the base optical waveguide through a light coupler, and the light incident through the optical coupler passes through the base optical waveguide And proceeds to the pixel line optical waveguide to which the pixel to be emitted by the optical switch belongs. Accordingly, when a voltage is applied to the pixel, the pixel emits light.

The driver required for this operation consists of a data driver and a gate driver.

Here, the data driver controls the amount of light that is transferred to the pixel line optical waveguide by applying a voltage to the optical switch.

The gate driver applies a voltage to a corresponding pixel row to cause the corresponding pixel to emit light using light falling along the pixel line optical waveguide.

The gradation representation of the pixel is determined by the intensity of the excitation light traveling to the corresponding pixel line optical waveguide and the intensity of the excitation light traveling to the pixel line optical waveguide is determined by the intensity change of the excitation light to the pixel , Or by modulating the intensity of external light incident on the optical coupler.

Since the display panel according to the present invention has a high degree of freedom in selecting a light emitting material, it is possible to realize a display having a high light efficiency and a high color number according to a selected light emitting material, and has a high pixel response speed and a high contrast ratio Display pixel implementation is possible.

Since all the elements are integrated on one glass substrate, the panel structure is simple, and a simple manufacturing process is possible.

In addition, it is possible to create various applications of the transparent display using the transparency of the display panel.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Will be apparent to those of ordinary skill in the art.

100: substrate 105: common electrode
110: cladding layer 120: gate electrode
125: gate connection wiring 130: core layer
160: refractive index variable layer 190: color conversion material
200: base light waveguide 250: pixel line light waveguide
250a: first optical waveguide 300: optical switch
400: Optocoupler 500: Pixel element array
300A: Optical Switch Array

Claims (27)

A substrate having a plurality of pixels defined in a matrix at a center thereof and a non-display area defined on an outer periphery of the pixel;
A light coupler formed in a non-display area of the substrate and adapted to receive light incident from the outside and enter the substrate;
A plurality of pixel elements formed on each of the pixels and adapted to emit light by modulating an optical field; And
And an optical switch array connected to the optical coupler for receiving the incident light and switching the light to the pixel device side for transmission. The method according to claim 1,
The optical switch array includes:
A backbone waveguide connected to the optical coupler in the non-display area, the incident light traveling in one direction;
A plurality of pixel line waveguides disposed in the non-display region in a direction crossing the base light pipe toward the pixel;
And an optical switch formed between the base optical waveguide and the pixel line optical waveguides and outputting the incident light to the pixel line optical waveguide. 3. The method of claim 2,
The pixel elements are arranged in a matrix,
A common electrode formed on the entire surface of the substrate;
A first optical waveguide formed on the common electrode, the first optical waveguide extending from the pixel line optical waveguide and passing the pixels;
A refractive index variable layer formed on the first optical waveguide;
A gate electrode formed on the refractive index variable layer in a row direction; And
And a color conversion material formed for each pixel on the gate electrode. The method according to claim 1,
Further comprising a light source for allowing light to enter the optical coupler. The method of claim 3,
Wherein the optical coupler is a second optical waveguide that receives the incident light and transmits the received light to the base optical waveguide. 6. The method of claim 5,
Wherein the optical coupler further comprises a grating on the surface of the second optical waveguide through which the incident light enters. 6. The method of claim 5,
Wherein the optical coupler further comprises a prism on a surface of the second optical waveguide through which the incident light is incident. 6. The method of claim 5,
Wherein the second optical waveguide through which the incident light enters further comprises a taper having a shape that narrows toward the base optical waveguide from the incident portion of the incident light. The method of claim 3,
And a data driver in the non-display area of the substrate adjacent to the optical switches. 10. The method of claim 9,
Wherein the data driver is connected to a data connection wiring formed on the optical switch. 11. The method of claim 10,
And the amount of light applied to the connected pixel line optical waveguide is adjusted according to a voltage value applied to the data connection wiring formed on the optical switch. 10. The method of claim 9,
Further comprising a gate driver connected to the gate electrode in an area of the non-display area on the substrate where the data driver is not formed. The method of claim 3,
Wherein the common electrode and the gate electrode are transparent electrodes. 14. The method of claim 13,
A gate voltage of 0V or a constant voltage is applied to the common electrode, and a gate-on voltage is sequentially applied to the gate electrode sequentially from the upper side to the lower side or from the lower side to the upper side. The method of claim 3,
Wherein the color conversion material is a light-emitting layer of a down-conversion material. 16. The method of claim 15,
Wherein the down-conversion material is a photo-luminescence material. 17. The method of claim 16,
Wherein the down conversion material is a fluorescent material or a phosphorescent material. The method of claim 3,
Wherein the refractive index-variable layer has a refractive index that varies electro-optically. The method of claim 3,
Wherein the first optical waveguide, the second optical waveguide, the base optical waveguide, and the pixel line optical waveguide each include a cladding layer and a core layer. 20. The method of claim 19,
The first optical waveguide, the second optical waveguide, the base optical waveguide, and the pixel line optical waveguide,
The clad layers are shared with each other,
And each of the core layers is separately patterned. 21. The method of claim 20,
Wherein a refractive index of each of the core layers is larger than a refractive index of each of the clad layers. 3. The method of claim 2,
Wherein the optical switch is a directional coupler element or a multimode interference (MMI) element. 21. The method of claim 20,
When the electric field is formed between the common electrode and the gate electrode,
Wherein the refractive index of the refractive index variable layer is changed to modulate the optical field of light transmitted to the first optical waveguide so that the modulated optical field tail is transmitted to the color conversion material. Preparing a substrate in which a plurality of pixels are defined in a matrix at a center, and a non-display area is defined in an outline of the pixel;
Forming a common electrode and a clad layer on the entire surface of the substrate;
A pixel core layer disposed adjacent to the base core layer in a direction intersecting with the base core layer; and a light emitting diode Forming a first core layer on the pixels extending in a traveling direction of the pixel line core layer;
Forming a refractive index variable layer on the clad layer including the optical coupler core layer, the base core layer, the pixel line core layer, and the first core layer;
Forming a gate electrode on the refractive index variable layer so as to pass through pixels in the horizontal direction; And
And forming a color conversion material corresponding to each pixel on the gate electrode. 25. The method of claim 24,
Further comprising forming a data connection wiring on the refractive index variable layer located between the adjacent base core layer and the pixel line core layer. 26. The method of claim 25,
And forming a gate connection wiring connected to each of the gate electrodes in the non-display region. 27. The method of claim 26,
A data driver connected to the data connection wiring, and a gate driver connected to the gate connection wiring.

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