KR20160061153A - Display device using semiconductor light emitting device - Google Patents

Abstract

The present invention relates to a display device. The display device comprises: a wiring board including a plurality of electrode lines; a conductive bonding layer connected with the wiring board; a plurality of semiconductor light-emitting devices electrically connected with the electrode lines, and coupled to the conductive bonding layer; a red luminescent material disposed along one of the electrode lines, and converting light emitted from the semiconductor light emitting devices arranged along the one line to red; and a green luminescent material disposed along another one of the electrode lines, and converting light emitted from the semiconductor light emitting devices arranged along the another one line to green. Luminescent areas included in the red and green luminescent materials are separately disposed with a separation unit interposed therebetween.

Description

Technical Field [0001] The present invention relates to a display device using a semiconductor light-

The present invention relates to a display device, and more particularly, to a display device using a semiconductor light emitting device.

 In recent years, display devices having excellent characteristics such as a thin shape and a flexible shape in the field of display technology have been developed. On the other hand, major displays that are commercialized today are represented by LCD (Liguid Crystal Display) and AMOLED (Active Matrix Organic Light Emitting Diodes).

On the other hand, in such a display device, the visibility is changed according to the surrounding brightness, and the outdoor display device usually requires higher luminance than the indoor display device.

An object of the present invention is to provide a display device capable of ensuring visibility in response to a change in ambient brightness.

Another object of the present invention is to provide a driving circuit for changing the brightness of a display device and a method thereof for improving the visibility of the display device in various ambient light environments such as night, indoor, and outdoor.

A display device according to the present invention includes a data electrode line, a semiconductor light emitting element electrically connected to the data electrode line, and supplied with a current supplied through the data electrode line, a semiconductor light emitting element electrically connected to the data electrode line, And the current mirror unit is controlled so that an amount of a current supplied to the semiconductor light emitting device is changed based on a current mirror unit and an ambient illuminance that adjust the amount of current supplied to the semiconductor light emitting device through the data electrode line, And a control unit for controlling the display unit.

In one embodiment of the present invention, the control unit drives the current mirror unit in one of the first operation mode and the second operation mode based on the ambient illuminance, And the amount of the supplied current is larger than the amount of the current supplied to the semiconductor light emitting element in the second operation mode.

In an embodiment, the ambient illuminance corresponding to the first operation mode is larger than the ambient illuminance corresponding to the second operation mode.

In an embodiment, the control unit controls a current supplied to the data electrode line by a PWM (Pulse Width Modulation) method, and the pulse voltage in the first operation mode and the pulse voltage in the second operation mode are different from each other do.

In an embodiment, the pulse voltage in the first operation mode is larger than the pulse voltage in the second operation mode.

In an embodiment, the amount of current supplied to the semiconductor light emitting element in the first operation mode is larger than the amount of current supplied to the semiconductor light emitting element in the second operation mode, and the pulse voltage Is larger than the pulse voltage in the second operation mode.

The semiconductor light emitting device may further include an illuminance sensor unit for sensing the ambient illuminance, and the control unit controls the amount of current supplied to the semiconductor light emitting unit using the sensing result of the illuminance sensor unit .

In one embodiment of the present invention, the control unit controls the current mirror unit to increase the amount of current supplied to the semiconductor light emitting device when the sensing result and the ambient illuminance are greater than a preset reference, The amount of current supplied to the semiconductor light emitting device is reduced by controlling the current mirror unit.

A display device including a semiconductor light emitting device that receives an electric current through an electrical connection with a data electrode line according to the present invention includes a step of sensing an ambient illuminance, and a step of, when the sensed ambient illuminance is greater than a reference illuminance, And controlling the current mirror unit electrically connected to the data electrode line and the semiconductor light emitting device so that the amount of current supplied to the device increases.

In one embodiment, the current supplied to the data electrode line is controlled by a PWM (Pulse Width Modulation) method, and the pulse voltage increases when the sensed ambient illuminance is greater than the reference illuminance.

According to the present invention, visibility of the display device can be ensured by changing the amount of current supplied to the display device in accordance with the change in ambient illuminance. Accordingly, it is possible to provide a display device regardless of various ambient light environments such as night, indoor, and outdoor.

1 is a conceptual diagram showing an embodiment of a display device using the semiconductor light emitting device of the present invention.
Fig. 2 is a partially enlarged view of part A of Fig. 1, and Figs. 3a and 3b are cross-sectional views taken along line BB and CC of Fig.
4 is a conceptual diagram showing a flip chip type semiconductor light emitting device of FIG. 3A.
FIGS. 5A to 5C are conceptual diagrams showing various forms of implementing a color in relation to a flip chip type semiconductor light emitting device.
6 is a cross-sectional view illustrating a method of manufacturing a display device using the semiconductor light emitting device of the present invention.
7 is a perspective view showing another embodiment of a display device using the semiconductor light emitting device of the present invention.
8 is a cross-sectional view taken along the line CC of Fig.
9 is a conceptual diagram showing a vertical semiconductor light emitting device of FIG.
10 is a block diagram illustrating a method of supplying current to a display device according to the present invention.
11 is a flowchart for explaining a method of supplying current to a display device according to the present invention.
FIG. 12 is a conceptual diagram for explaining the current supplying method shown in FIGS. 10 and 11. FIG.
13 is a conceptual diagram for explaining a plurality of modes in which the amounts of current supply are different from each other.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals are used to designate identical or similar elements, and redundant description thereof will be omitted. The suffix "module" and " part "for the components used in the following description are given or mixed in consideration of ease of specification, and do not have their own meaning or role. In the following description of the embodiments of the present invention, a detailed description of related arts will be omitted when it is determined that the gist of the embodiments disclosed herein may be blurred. In addition, it should be noted that the attached drawings are only for easy understanding of the embodiments disclosed in the present specification, and should not be construed as limiting the technical idea disclosed in the present specification by the attached drawings.

It is also to be understood that when an element such as a layer, region or substrate is referred to as being present on another element "on," it is understood that it may be directly on the other element or there may be an intermediate element in between There will be.

The display device described in this specification includes a mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation device, a slate PC, , A Tablet PC, an Ultra Book, a digital TV, a desktop computer, and the like. However, it will be readily apparent to those skilled in the art that the configuration according to the embodiments described herein may be applied to a device capable of being displayed, even in the form of a new product to be developed in the future.

1 is a conceptual diagram showing an embodiment of a display device using the semiconductor light emitting device of the present invention.

According to the illustrated example, the information processed in the control unit of the display device 100 may be displayed using a flexible display.

The flexible display includes a display that can be bent, twistable, collapsible, and curlable, which can be bent by an external force. For example, a flexible display can be a display made on a thin, flexible substrate that can be bent, bent, folded or rolled like paper while maintaining the display characteristics of conventional flat panel displays.

In a state where the flexible display is not bent (for example, a state having an infinite radius of curvature, hereinafter referred to as a first state), the display area of the flexible display is flat. In the first state, the display area may be a curved surface in a state of being bent by an external force (for example, a state having a finite radius of curvature, hereinafter referred to as a second state). As shown in the figure, the information displayed in the second state may be time information output on the curved surface. Such visual information is realized by independently controlling the emission of a sub-pixel arranged in a matrix form. The unit pixel means a minimum unit for implementing one color formed by a combination of R, G, and B.

The unit pixel of the flexible display may be implemented by a semiconductor light emitting device. In the present invention, a light emitting diode (LED) is exemplified as one type of semiconductor light emitting device for converting a current into light. The light emitting diode is formed in a small size, so that it can serve as a unit pixel even in the second state.

Hereinafter, a flexible display implemented using the light emitting diode will be described in detail with reference to the drawings.

3 is a cross-sectional view taken along line BB in Fig. 2, Fig. 4 is a conceptual view showing a flip chip type semiconductor light emitting device in Fig. 3, and Figs. 5A to 5C Are conceptual diagrams showing various forms of implementing a color in relation to a flip chip type semiconductor light emitting device.

Referring to FIGS. 2, 3A and 3B, a display device 100 using a passive matrix (PM) semiconductor light emitting device as a display device 100 using a semiconductor light emitting device is illustrated. However, the example described below is also applicable to an active matrix (AM) semiconductor light emitting device.

The display device 100 includes a substrate 110, a first electrode 120, a conductive adhesive layer 130, a second electrode 140, and a plurality of semiconductor light emitting devices 150.

The substrate 110 may be a flexible substrate. For example, to implement a flexible display device, the substrate 110 may comprise glass or polyimide (PI). In addition, any insulating material such as PEN (polyethylene naphthalate) and PET (polyethylene terephthalate) may be used as long as it is insulating and flexible. In addition, the substrate 110 may be either a transparent material or an opaque material.

The substrate 110 may be a wiring substrate on which the first electrode 120 is disposed, so that the first electrode 120 may be positioned on the substrate 110.

The insulating layer 160 may be disposed on the substrate 110 on which the first electrode 120 is located and the auxiliary electrode 170 may be disposed on the insulating layer 160. In this case, a state in which the insulating layer 160 is laminated on the substrate 110 may be one wiring substrate. More specifically, the insulating layer 160 is formed of a flexible material such as polyimide (PI), polyimide (PET), or PEN, and is integrally formed with the substrate 110 to form a single substrate.

The auxiliary electrode 170 is an electrode that electrically connects the first electrode 120 and the semiconductor light emitting device 150 and is disposed on the insulating layer 160 and corresponds to the position of the first electrode 120. For example, the auxiliary electrode 170 may be in the form of a dot and may be electrically connected to the first electrode 120 by an electrode hole 171 passing through the insulating layer 160. The electrode hole 171 may be formed by filling a via hole with a conductive material.

Referring to these drawings, the conductive adhesive layer 130 is formed on one surface of the insulating layer 160, but the present invention is not limited thereto. For example, a layer having a specific function may be formed between the insulating layer 160 and the conductive adhesive layer 130, or a structure in which the conductive adhesive layer 130 is disposed on the substrate 110 without the insulating layer 160 It is also possible. In the structure in which the conductive adhesive layer 130 is disposed on the substrate 110, the conductive adhesive layer 130 may serve as an insulating layer.

The conductive adhesive layer 130 may be a layer having adhesiveness and conductivity. To this end, the conductive adhesive layer 130 may be mixed with a substance having conductivity and a substance having adhesiveness. Also, the conductive adhesive layer 130 has ductility, thereby enabling the flexible function in the display device.

As an example, the conductive adhesive layer 130 may be an anisotropic conductive film (ACF), an anisotropic conductive paste, a solution containing conductive particles, or the like. The conductive adhesive layer 130 may be formed as a layer having electrical insulation in the horizontal X-Y direction while permitting electrical interconnection in the Z direction passing through the thickness. Accordingly, the conductive adhesive layer 130 may be referred to as a Z-axis conductive layer (hereinafter, referred to as a conductive adhesive layer).

The anisotropic conductive film is a film in which an anisotropic conductive medium is mixed with an insulating base member. When heat and pressure are applied, only a specific part of the anisotropic conductive film has conductivity due to the anisotropic conductive medium. Hereinafter, the anisotropic conductive film is described as being subjected to heat and pressure, but other methods may be used to partially conduct the anisotropic conductive film. In this method, for example, either the heat or the pressure may be applied, or UV curing may be performed.

In addition, the anisotropic conduction medium can be, for example, a conductive ball or a conductive particle. According to the example, in the present example, the anisotropic conductive film is a film in which conductive balls are mixed with an insulating base member. When heat and pressure are applied, only specific portions are conductive by the conductive balls. The anisotropic conductive film may be a state in which a plurality of particles coated with an insulating film made of a polymer material are contained in the core of the conductive material. In this case, the insulating film is broken by heat and pressure, . At this time, the shape of the core may be deformed to form a layer in contact with each other in the thickness direction of the film. As a more specific example, heat and pressure are applied to the anisotropic conductive film as a whole, and the electrical connection in the Z-axis direction is partially formed by the height difference of the mating member adhered by the anisotropic conductive film.

As another example, the anisotropic conductive film may be in a state in which a plurality of particles coated with a conductive material are contained in the insulating core. In this case, the conductive material is deformed (pressed) to the portion where the heat and the pressure are applied, so that the conductive material becomes conductive in the thickness direction of the film. As another example, it is possible that the conductive material penetrates the insulating base member in the Z-axis direction and has conductivity in the thickness direction of the film. In this case, the conductive material may have a pointed end.

According to the present invention, the anisotropic conductive film may be a fixed array anisotropic conductive film (ACF) in which conductive balls are inserted into one surface of an insulating base member. More specifically, the insulating base member is formed of a material having adhesiveness, and the conductive ball is concentrated on the bottom portion of the insulating base member, and is deformed together with the conductive ball when heat and pressure are applied to the base member So that they have conductivity in the vertical direction.

However, the present invention is not limited thereto. The anisotropic conductive film may be formed by randomly mixing conductive balls into an insulating base member or by forming a plurality of layers in which a conductive ball is placed in a double- ACF) are all available.

The anisotropic conductive paste is a combination of a paste and a conductive ball, and may be a paste in which a conductive ball is mixed with an insulating and adhesive base material. In addition, solutions containing conductive particles can be solutions in the form of conductive particles or nanoparticles.

Referring again to FIG. 5, the second electrode 140 is located in the insulating layer 160, away from the auxiliary electrode 170. That is, the conductive adhesive layer 130 is disposed on the insulating layer 160 on which the auxiliary electrode 170 and the second electrode 140 are disposed.

After the conductive adhesive layer 130 is formed in a state where the auxiliary electrode 170 and the second electrode 140 are positioned in the insulating layer 160, the semiconductor light emitting device 150 is connected to the semiconductor light emitting device 150 in a flip chip form The semiconductor light emitting device 150 is electrically connected to the first electrode 120 and the second electrode 140.

Referring to FIG. 4, the semiconductor light emitting device may be a flip chip type light emitting device.

For example, the semiconductor light emitting device includes a p-type semiconductor layer 155 in which a p-type electrode 156, a p-type electrode 156 are formed, an active layer 154 formed on the p-type semiconductor layer 155, And an n-type electrode 152 disposed on the n-type semiconductor layer 153 and the p-type electrode 156 on the n-type semiconductor layer 153 and 154 in the horizontal direction. In this case, the p-type electrode 156 may be electrically connected to the auxiliary electrode 170 by the conductive adhesive layer 130, and the n-type electrode 152 may be electrically connected to the second electrode 140.

Referring again to FIGS. 2, 3A and 3B, the auxiliary electrode 170 is elongated in one direction, and one auxiliary electrode may be electrically connected to the plurality of semiconductor light emitting devices 150. For example, the p-type electrodes of the right and left semiconductor light emitting elements may be electrically connected to one auxiliary electrode around the auxiliary electrode.

More specifically, the semiconductor light emitting device 150 is inserted into the conductive adhesive layer 130 by heat and pressure, and the semiconductor light emitting device 150 is inserted into the conductive adhesive layer 130 through the p- And only the portion between the n-type electrode 152 and the second electrode 140 of the semiconductor light emitting device 150 has conductivity and the semiconductor light emitting device does not have a conductive property because the semiconductor light emitting device is not press- The conductive adhesive layer 130 not only couples the semiconductor light emitting device 150 and the auxiliary electrode 170 and the semiconductor light emitting device 150 and the second electrode 140 but also forms an electrical connection.

In addition, the plurality of semiconductor light emitting devices 150 constitute a light emitting element array, and the phosphor layer 180 is formed in the light emitting element array.

The light emitting element array may include a plurality of semiconductor light emitting elements having different brightness values. Each of the semiconductor light emitting devices 150 is combined (or grouped) to form a unit pixel, and is electrically connected to the first electrode 120. For example, the first electrodes 120 may be a plurality of semiconductor light emitting devices, and the semiconductor light emitting devices may be electrically connected to any one of the plurality of first electrodes.

Also, since the semiconductor light emitting devices are connected in a flip chip form, the semiconductor light emitting devices grown on the transparent dielectric substrate can be used. The semiconductor light emitting devices may be, for example, a nitride semiconductor light emitting device. Since the semiconductor light emitting device 150 has excellent brightness, individual unit pixels can be formed with a small size.

According to the structure, the barrier ribs 190 may be formed between the semiconductor light emitting devices 150. In this case, the barrier ribs 190 may separate the semiconductor light emitting devices from each other, and may be integrally formed with the conductive adhesive layer 130. For example, by inserting the semiconductor light emitting device 150 into the anisotropic conductive film, the base member of the anisotropic conductive film can form the partition.

Also, if the base member of the anisotropic conductive film is black, the barrier 190 may have a reflection characteristic and a contrast may be increased without a separate black insulator.

As another example, the barrier ribs 190 may be provided separately from the reflective barrier ribs. In this case, the barrier rib 190 may include a black or white insulation depending on the purpose of the display device. When a barrier of a white insulator is used, an effect of enhancing reflectivity may be obtained. When a barrier of a black insulator is used, a contrast characteristic may be increased while having a reflection characteristic.

The phosphor layer 180 may be located on the outer surface of the semiconductor light emitting device 150. For example, the semiconductor light emitting device 150 is a blue semiconductor light emitting device that emits blue (B) light, and the phosphor layer 180 converts the blue (B) light into the color of a unit pixel. The phosphor layer 180 may be a red phosphor 181 or a green phosphor 182 constituting an individual pixel.

That is, a red phosphor 181 capable of converting blue light into red (R) light can be laminated on the blue semiconductor light emitting element 151 at a position forming a red unit pixel, A green phosphor 182 capable of converting blue light into green (G) light may be laminated on the blue semiconductor light emitting element 151. [ In addition, only the blue semiconductor light emitting element 151 can be used alone in a portion constituting a blue unit pixel. In this case, the unit pixels of red (R), green (G), and blue (B) can form one pixel. More specifically, phosphors of one color may be stacked along each line of the first electrode 120. Accordingly, one line in the first electrode 120 may be an electrode for controlling one color. In other words, red (R), green (G), and blue (B) may be arranged in order along the second electrode 140, thereby realizing a unit pixel.

However, the present invention is not limited thereto. Instead, the semiconductor light emitting device 150 and the quantum dot QD may be combined to form a unit pixel emitting red (R), green (G), and blue (B) Can be implemented.

In addition, a black matrix 191 may be disposed between each of the phosphor layers to improve contrast. That is, the black matrix 191 can improve the contrast of light and dark.

However, the present invention is not limited thereto, and other structures for implementing blue, red, and green may be applied.

5A, each of the semiconductor light emitting devices 150 includes gallium nitride (GaN), indium (In) and / or aluminum (Al) are added together to form a high output light Device.

In this case, the semiconductor light emitting device 150 may be a red, green, and blue semiconductor light emitting device to form a unit pixel (sub-pixel), respectively. For example, red, green, and blue semiconductor light emitting elements R, G, and B are alternately arranged, and red, green, and blue unit pixels Form a single pixel, through which a full color display can be implemented.

Referring to FIG. 5B, the semiconductor light emitting device may include a white light emitting device W having a yellow phosphor layer for each individual device. In this case, a red phosphor layer 181, a green phosphor layer 183, and a blue phosphor layer 183 may be provided on the white light emitting element W to form a unit pixel. Further, a unit pixel can be formed by using a color filter in which red, green, and blue are repeated on the white light emitting element W.

Referring to FIG. 5C, a red phosphor layer 181, a green phosphor layer 182, and a blue phosphor layer 183 may be provided on the ultraviolet light emitting element UV. As described above, the semiconductor light emitting device can be used not only for visible light but also for ultraviolet (UV), and can be extended to a form of a semiconductor light emitting device in which ultraviolet (UV) can be used as an excitation source of the upper phosphor .

The semiconductor light emitting device 150 is disposed on the conductive adhesive layer 130 and constitutes a unit pixel in the display device. Since the semiconductor light emitting device 150 has excellent brightness, individual unit pixels can be formed with a small size. The size of the individual semiconductor light emitting device 150 may be 80 mu m or less on one side and may be a rectangular or square device. In the case of a rectangle, the size may be 20 X 80 μm or less.

Also, even if a square semiconductor light emitting device 150 having a length of 10 m on one side is used as a unit pixel, sufficient brightness for forming a display device appears. Accordingly, when the unit pixel is a rectangular pixel having a side of 600 mu m and the other side of 300 mu m as an example, the distance of the semiconductor light emitting element becomes relatively large. Accordingly, in such a case, it becomes possible to implement a flexible display device having HD picture quality.

The display device using the semiconductor light emitting device described above can be manufactured by a novel manufacturing method. Hereinafter, the manufacturing method will be described with reference to FIG.

6 is a cross-sectional view illustrating a method of manufacturing a display device using the semiconductor light emitting device of the present invention.

The conductive adhesive layer 130 is formed on the insulating layer 160 on which the auxiliary electrode 170 and the second electrode 140 are disposed. A first electrode 120, an auxiliary electrode 170, and a second electrode 140 are formed on the wiring substrate, and the insulating layer 160 is formed on the first substrate 110 to form a single substrate (or a wiring substrate) . In this case, the first electrode 120 and the second electrode 140 may be arranged in mutually orthogonal directions. In addition, the first substrate 110 and the insulating layer 160 may include glass or polyimide (PI), respectively, in order to implement a flexible display device.

The conductive adhesive layer 130 may be formed, for example, by an anisotropic conductive film, and an anisotropic conductive film may be applied to the substrate on which the insulating layer 160 is disposed.

A second substrate 112 corresponding to the positions of the auxiliary electrode 170 and the second electrodes 140 and having a plurality of semiconductor light emitting elements 150 constituting individual pixels is disposed on the semiconductor light emitting element 150 Are arranged so as to face the auxiliary electrode 170 and the second electrode 140.

In this case, the second substrate 112 is a growth substrate for growing the semiconductor light emitting device 150, and may be a spire substrate or a silicon substrate.

When the semiconductor light emitting device is formed in units of wafers, the semiconductor light emitting device can be effectively used in a display device by having an interval and a size at which a display device can be formed.

Then, the wiring substrate and the second substrate 112 are thermally bonded. For example, the wiring board and the second substrate 112 may be thermocompression-bonded using an ACF press head. The wiring substrate and the second substrate 112 are bonded by the thermocompression bonding. Only the portion between the semiconductor light emitting device 150 and the auxiliary electrode 170 and the second electrode 140 has conductivity due to the characteristics of the anisotropic conductive film having conductivity by thermocompression, The device 150 may be electrically connected. At this time, the semiconductor light emitting device 150 is inserted into the anisotropic conductive film, and partition walls may be formed between the semiconductor light emitting devices 150.

Then, the second substrate 112 is removed. For example, the second substrate 112 may be removed using a laser lift-off method (LLO) or a chemical lift-off method (CLO).

Finally, the second substrate 112 is removed to expose the semiconductor light emitting devices 150 to the outside. If necessary, a transparent insulating layer (not shown) may be formed by coating a wiring substrate on which the semiconductor light emitting device 150 is coupled with silicon oxide (SiOx) or the like.

Further, the method may further include forming a phosphor layer on one surface of the semiconductor light emitting device 150. For example, the semiconductor light emitting device 150 is a blue semiconductor light emitting device that emits blue (B) light, and a red phosphor or a green phosphor for converting the blue (B) A layer can be formed on one surface of the device.

The manufacturing method and structure of the display device using the semiconductor light emitting device described above can be modified into various forms. For example, a vertical semiconductor light emitting device may be applied to the display device described above. Hereinafter, the vertical structure will be described with reference to Figs. 5 and 6. Fig.

In the modifications or embodiments described below, the same or similar reference numerals are given to the same or similar components as those of the previous example, and the description is replaced with the first explanation.

8 is a cross-sectional view taken along the line CC of FIG. 7, and FIG. 9 is a conceptual view illustrating a vertical semiconductor light emitting device of FIG. 8. FIG. 7 is a perspective view showing another embodiment of a display device using the semiconductor light emitting device of the present invention, to be.

Referring to these drawings, the display device may be a display device using a passive matrix (PM) vertical semiconductor light emitting device.

The display device includes a substrate 210, a first electrode 220, a conductive adhesive layer 230, a second electrode 240, and a plurality of semiconductor light emitting devices 250.

The substrate 210 is a wiring substrate on which the first electrode 220 is disposed. The substrate 210 may include polyimide (PI) to implement a flexible display device. In addition, any insulating and flexible material may be used.

The first electrode 220 is disposed on the substrate 210 and may be formed as a long bar electrode in one direction. The first electrode 220 may serve as a data electrode.

A conductive adhesive layer 230 is formed on the substrate 210 on which the first electrode 220 is located. The conductive adhesive layer 230 may be formed of an anisotropic conductive film (ACF), an anisotropic conductive paste, a solution containing a conductive particle, or the like, as in a display device using a flip chip type light emitting device. ) And the like. However, the present embodiment also exemplifies the case where the conductive adhesive layer 230 is realized by the anisotropic conductive film.

If the semiconductor light emitting device 250 is connected to the semiconductor light emitting device 250 by applying heat and pressure after the anisotropic conductive film is positioned in a state where the first electrode 220 is positioned on the substrate 210, And is electrically connected to the electrode 220. In this case, the semiconductor light emitting device 250 may be disposed on the first electrode 220.

As described above, the electrical connection is generated because heat and pressure are applied to the anisotropic conductive film to partially conduct in the thickness direction. Therefore, in the anisotropic conductive film, it is divided into a portion 231 having conductivity in the thickness direction and a portion 232 having no conductivity.

In addition, since the anisotropic conductive film contains an adhesive component, the conductive adhesive layer 230 realizes electrical connection as well as mechanical bonding between the semiconductor light emitting element 250 and the first electrode 220.

Thus, the semiconductor light emitting device 250 is positioned on the conductive adhesive layer 230, thereby forming individual pixels in the display device. Since the semiconductor light emitting device 250 has excellent brightness, individual unit pixels can be formed with a small size. The size of the individual semiconductor light emitting device 250 may be 80 μm or less on one side and may be a rectangular or square device. In the case of a rectangle, the size may be 20 X 80 μm or less.

The semiconductor light emitting device 250 may have a vertical structure.

A plurality of second electrodes 240 electrically connected to the vertical semiconductor light emitting device 250 are disposed between the vertical semiconductor light emitting devices in a direction crossing the longitudinal direction of the first electrode 220.

9, the vertical type semiconductor light emitting device includes a p-type electrode 256, a p-type semiconductor layer 255 formed on the p-type electrode 256, an active layer 254 formed on the p-type semiconductor layer 255 An n-type semiconductor layer 253 formed on the active layer 254 and an n-type electrode 252 formed on the n-type semiconductor layer 253. In this case, the p-type electrode 256 located at the bottom may be electrically connected to the first electrode 220 by the conductive adhesive layer 230, and the n-type electrode 252 located at the top may be electrically connected to the second electrode 240 As shown in FIG. Since the vertical semiconductor light emitting device 250 can arrange the electrodes up and down, it has a great advantage that the chip size can be reduced.

Referring to FIG. 8 again, a phosphor layer 280 may be formed on one side of the semiconductor light emitting device 250. For example, the semiconductor light emitting device 250 is a blue semiconductor light emitting device 251 that emits blue (B) light, and a phosphor layer 280 for converting the blue (B) . In this case, the phosphor layer 280 may be a red phosphor 281 and a green phosphor 282 constituting individual pixels.

That is, a red phosphor 281 capable of converting blue light into red (R) light can be laminated on the blue semiconductor light emitting element 251 at a position forming a red unit pixel, A green phosphor 282 capable of converting blue light into green (G) light may be laminated on the blue semiconductor light emitting element 251. In addition, only the blue semiconductor light emitting element 251 can be used alone in a portion constituting a blue unit pixel. In this case, the unit pixels of red (R), green (G), and blue (B) can form one pixel.

However, the present invention is not limited thereto, and other structures for implementing blue, red, and green may be applied to a display device to which a flip chip type light emitting device is applied, as described above.

The second electrode 240 is located between the semiconductor light emitting devices 250 and electrically connected to the semiconductor light emitting devices 250. For example, the semiconductor light emitting devices 250 may be disposed in a plurality of rows, and the second electrode 240 may be disposed between the columns of the semiconductor light emitting devices 250.

The second electrode 240 may be positioned between the semiconductor light emitting devices 250 because the distance between the semiconductor light emitting devices 250 forming the individual pixels is sufficiently large.

The second electrode 240 may be formed as a long bar-shaped electrode in one direction and may be disposed in a direction perpendicular to the first electrode.

The second electrode 240 and the semiconductor light emitting device 250 may be electrically connected by a connection electrode protruding from the second electrode 240. More specifically, the connection electrode may be an n-type electrode of the semiconductor light emitting device 250. For example, the n-type electrode is formed as an ohmic electrode for ohmic contact, and the second electrode covers at least a part of the ohmic electrode by printing or vapor deposition. Accordingly, the second electrode 240 and the n-type electrode of the semiconductor light emitting device 250 can be electrically connected.

According to the example, the second electrode 240 may be disposed on the conductive adhesive layer 230. A transparent insulating layer (not shown) containing silicon oxide (SiOx) or the like may be formed on the substrate 210 on which the semiconductor light emitting device 250 is formed. When the second electrode 240 is positioned after the transparent insulating layer is formed, the second electrode 240 is positioned on the transparent insulating layer. In addition, the second electrode 240 may be formed spaced apart from the conductive adhesive layer 230 or the transparent insulating layer.

If a transparent electrode such as ITO (Indium Tin Oxide) is used for positioning the second electrode 240 on the semiconductor light emitting device 250, the problem that the ITO material has poor adhesion with the n-type semiconductor layer have. Accordingly, the present invention has an advantage in that the second electrode 240 is positioned between the semiconductor light emitting devices 250, so that a transparent electrode such as ITO is not used. Therefore, the light extraction efficiency can be improved by using a conductive material having good adhesiveness with the n-type semiconductor layer as a horizontal electrode without being bound by transparent material selection.

According to the structure, the barrier ribs 290 may be positioned between the semiconductor light emitting devices 250. That is, the barrier ribs 290 may be disposed between the vertical semiconductor light emitting devices 250 to isolate the semiconductor light emitting devices 250 forming the individual pixels. In this case, the barrier ribs 290 may separate the individual unit pixels from each other, and may be formed integrally with the conductive adhesive layer 230. For example, by inserting the semiconductor light emitting device 250 into the anisotropic conductive film, the base member of the anisotropic conductive film can form the partition.

Also, if the base member of the anisotropic conductive film is black, the barrier ribs 290 may have a reflection characteristic and a contrast may be increased without a separate black insulator.

As another example, as the partition 190, a reflective barrier may be separately provided. The barrier ribs 290 may include black or white insulators depending on the purpose of the display device.

If the second electrode 240 is directly disposed on the conductive adhesive layer 230 between the semiconductor light emitting devices 250, the barrier ribs 290 may be formed between the vertical semiconductor light emitting device 250 and the second electrode 240 As shown in FIG. Therefore, individual unit pixels can be formed with a small size by using the semiconductor light emitting device 250, and the distance between the semiconductor light emitting device 250 can be relatively large enough so that the second electrode 240 can be electrically connected to the semiconductor light emitting device 250 ), And it is possible to realize a flexible display device having HD picture quality.

In addition, according to the present invention, a black matrix 291 may be disposed between the respective phosphors to improve the contrast. That is, this black matrix 291 can improve the contrast of light and dark.

Hereinafter, a method of providing a display device capable of ensuring visibility in response to a change in ambient brightness will be described in detail with reference to the accompanying drawings. FIG. 10 is a block diagram for explaining a method of supplying current to a display device according to the present invention, FIG. 11 is a flowchart for explaining a method of supplying current to a display device according to the present invention, And FIG. 11 is a conceptual diagram for explaining the current supply method. 13 is a conceptual diagram for explaining a plurality of modes in which the amounts of current supply are different from each other.

10, a display device according to the present invention includes a control unit 1010, a current mirror unit (not shown) for controlling the amount of current supplied to the semiconductor light emitting device 1051 under the control of the control unit 1010, 1015).

As described above, the semiconductor light emitting device 1051 is connected to the first electrode unit 1020 and the second electrode unit 1030, thereby supplying an operation current or operation power for driving the semiconductor light emitting device 1051 You can receive. Here, the first electrode unit 1020 and the second electrode unit 1030 are electrically connected to the plurality of semiconductor light emitting devices 1051. The first electrode unit 1020 may serve as a data electrode and the second electrode unit 1030 may serve as a scan electrode.

The first electrode unit 1020 serving as a data electrode may be composed of a plurality of data electrode lines. The semiconductor light emitting device 1051 may operate by receiving a current through a data electrode line corresponding to the first electrode unit 1020.

At this time, the controller 1010 can adjust the amount of the current supplied through the data electrode line based on the ambient illuminance. The brightness of the semiconductor light emitting element 1051 in the case where the amount of current supplied to the semiconductor light emitting element 1051 is large is determined by the brightness of the semiconductor light emitting element 1051 when the amount of current supplied to the semiconductor light emitting element 1051 is small It is brighter.

That is, the brightness of the semiconductor light emitting element 1051 when the amount of current supplied to the semiconductor light emitting element 1051 is large is larger than the brightness of the semiconductor light emitting element 1051 when the amount of current supplied to the semiconductor light emitting element 1051 is small. Lt; / RTI >

For example, in a bright environment due to sunlight or the like, that is, when the peripheral illuminance of the display device is large, the amount of current flowing through the semiconductor light emitting element 1051 must be large in order to ensure visibility of the display device. In a dark environment, that is, when the peripheral illuminance of the display device is small, the amount of current flowing through the semiconductor light emitting element 1051 is relatively smaller than the amount of current in a bright environment.

Thus, in the present invention, it is possible to propose a control method capable of immediately responding to the illuminance according to the surrounding environment by adjusting the amount of current flowing through the semiconductor light emitting element 1051 according to the ambient illuminance.

Referring to FIG. 11, a control method for controlling the amount of current flowing through the semiconductor light emitting device 1051 will be described. First, a step of sensing the ambient illuminance of the display device is performed (S 1110).

The display device according to the present invention may further include an illuminance sensor unit for sensing the ambient illuminance. The sensing of the ambient illuminance can be performed in real time, and can be performed at predetermined time intervals.

On the other hand, when the ambient illuminance is sensed, a step of comparing the sensed ambient illuminance and the reference illuminance is performed (S1120). Then, the step of controlling the amount of the current supplied to the semiconductor light emitting element 1051 proceeds according to the comparison result (S1130).

Here, the reference illuminance may be set in advance from the time of product release, or may be set based on the user's selection.

In the display device according to the present invention, when the ambient illuminance corresponds to the reference illuminance, the amount of current flowing through the semiconductor light emitting element 1051 may be set in advance. Therefore, the controller 1010 can control the amount of current flowing through the semiconductor light emitting element 1051 to be greater than or equal to the reference value, if i) the ambient illuminance corresponds to the reference illuminance, or ii) when the difference between the ambient illuminance and the reference illuminance is within a predetermined range, It is possible to control the amount of current according to the illuminance.

If the difference between the sensed ambient illuminance and the reference illuminance or the predetermined range is exceeded, the control unit 1010 controls the amount of current flowing in the semiconductor light emitting element 1051 to be larger than the amount of current according to the reference illuminance You can control more or less.

Meanwhile, the display device according to the present invention may be driven in either the visible mode (or the first operation mode) or the normal mode (or the second operation mode) according to the ambient illuminance.

More specifically, when the sensed ambient illuminance is greater than the reference illuminance and the difference between the sensed ambient illuminance and the reference illuminance is greater than a predetermined range (or greater than a predetermined range) The display device can be driven in the visibility mode. The visibility mode may mean a mode in which the amount of current flowing in the semiconductor light emitting element 1051 is relatively larger than the normal mode in order to ensure the visibility of the display device in a bright ambient environment.

That is, the amount of current supplied to the semiconductor light emitting element 1051 in the visibility mode (or the first operation mode) is larger than the amount of current supplied to the semiconductor light emitting element in the normal mode (or the second operation mode).

On the other hand, when the sensed ambient illuminance is smaller than the reference illuminance, the control unit 1010 can drive the display device in the normal mode.

The controller 1010 can change the driving mode of the display device when the sensed ambient illuminance is smaller than the reference illuminance as a result of sensing the ambient illuminance while the display device is being driven in the visibility mode. At this time, the driving mode of the display device can be switched from the visibility mode to the normal mode.

Further, when the sensed ambient illuminance is greater than the reference illuminance as a result of sensing the ambient illuminance while the display apparatus is being driven in the normal mode, the control unit 1010 can change the drive mode of the display apparatus. At this time, the drive mode of the display device can be switched to the visibility mode in the normal mode.

Further, if the sensed ambient illuminance is smaller than the reference illuminance as a result of sensing the ambient illuminance while the display device is being driven in the normal mode, the control unit 1010 continues the drive mode of the display apparatus to the normal mode Can be maintained.

Further, when the sensed ambient illuminance is greater than the reference illuminance as a result of sensing the ambient illuminance while the display device is being driven in the visibility mode, the control unit 1010 continues the drive mode of the display device in the visibility mode Can be maintained.

Hereinafter, a method for controlling the amount of current provided to the semiconductor light emitting element in the visible mode and the normal mode will be described in more detail.

12, the control unit 1010 of the display apparatus according to the present invention may further include a voltage regulator and a pulse generator.

The current mirror portion 1015 may include Q1, Q2, Q3 switches, Rset, and Rbr resistors. As shown in the figure, the switches Q1 and Q2 correspond to a constant current circuit for constantly controlling the current If flowing in the data electrode line, and the switch Q3 switches the current Iref supplied in the visibility mode and the normal mode It corresponds to the switch to change.

The Rset resistance is a resistance for setting the Iref current, and the Rbr resistance is a resistance for increasing the amount of current in the visibility mode.

The control section 1010 can change the Iref current to control the amount of current flowing through the semiconductor light emitting element in the visibility mode included in the current mirror section 1015 and the normal mode differently. This change in the Iref current can be achieved by controlling the Q3 switch, Rset, and Rbr resistance, that is, the current mirror section 1015 under the control of the control section 1010. [

The switch Q4 corresponds to a switch for electrically connecting the second electrode unit 1030 (or the scan electrode and the scan electrode line) to the semiconductor light emitting device 1051 so that current flows through the semiconductor light emitting device 1051 .

As described above, the control unit 1010 can increase or decrease the amount of the current If flowing through the data electrode lines by controlling the current mirror unit 1015.

On the other hand, in the visibility mode, since the amount of current supplied to the semiconductor light emitting element is larger than that in the normal mode, when the magnitude of the current is changed, the power consumption by the scan electrode (or the second electrode) .

Therefore, in the present invention, by increasing the pulse voltage in the PWM (Pulse Width Modulation) control for driving the semiconductor light emitting element, the driving voltage (VDD) is increased in the visible mode than in the normal mode, The luminance of the semiconductor light emitting element 1051 can be increased while the amount thereof is reduced.

That is, in order to secure the brightness of the semiconductor light emitting device 1051 required in the visibility mode, the control unit 1010 does not increase the amount of current but increases the driving voltage So that the brightness of the semiconductor light emitting element 1051 can be ensured while the amount of current is reduced.

In this way, when the amount of current supplied in the visibility mode is reduced, the power consumption consumed by the scan electrode can be reduced. In other words, the control unit 1010 can reduce the power consumption by changing the driving voltage VDD according to the PWM control method when converting to the visibility mode in the normal mode.

On the other hand, the controller 1010 can adjust the driving voltage VDD during the PWM control to be different from the driving voltage VDD according to the PWM control method in the normal mode and the visibility mode. The driving voltage can be changed through the above-described voltage variable regulator.

More specifically, the control unit 1010 drives the display device in the normal mode when the sensed ambient illuminance is smaller than the reference illuminance as a result of sensing the ambient illuminance. The driving voltage in the normal mode is VDD1, and the current flowing in the data electrode line may be If1.

If the sensed ambient illuminance is greater than the reference illuminance as a result of sensing the ambient illuminance, the control unit 1010 drives the display apparatus in the view mode. The driving voltage in the visibility mode is VDD2, and the current flowing in the data electrode line may be If2.

As shown in the figure, the driving voltage VDD1 in the normal mode is smaller than the driving voltage VDD2 in the visibility mode. That is, the controller 1010 can control the pulse voltage in the normal mode and the visibility mode differently through the voltage variable regulator, thereby reducing power consumption in the display device.

Further, the amount of the current If1 flowing to the data electrode line in the normal mode is smaller than the drive current If2 in the visibility mode. In other words, the control unit 1010 can control the luminance of the display device by controlling the supply current in the normal mode and the visibility mode differently by controlling the current mirror unit 1015. [

As described above, according to the present invention, the controller 1010 controls the current mirror unit 1015 in the visibility mode (or the first operation mode) and the normal mode (or the second operation mode) based on the sensed ambient illuminance It is driven in any one of the operation modes. The amount of current supplied to the semiconductor light emitting element 1051 in the visible mode is larger than the amount of current supplied to the semiconductor light emitting element 1051 in the normal mode.

Further, the gating and control unit 1010 controls not only the amount of current flowing in the semiconductor light emitting device 1051 but also the driving voltage corresponding to the pulse voltage by using a voltage variable regulator, The power consumption can be reduced while securing the brightness of the display device.

As described above, the display device according to the present invention can ensure the visibility of the display device in the visible mode by controlling the amount of current supplied to the semiconductor light emitting element in the visible mode and the normal mode. Accordingly, it is possible to provide a display device regardless of various ambient light environments such as night, indoor, and outdoor.

Furthermore, the display device according to the present invention can reduce the power consumption in the display device by increasing the driving voltage in the visibility mode.

Alternatively, the control unit 1010 can compare the sensed ambient illuminance with the illuminance corresponding to the amount of the current flowing through the semiconductor light emitting element 1051. In this case, when the sensed ambient illuminance is greater than the illuminance corresponding to the amount of current flowing through the semiconductor light emitting element 1051, the controller 1010 controls the semiconductor light emitting element 1051 so that the current flowing through the semiconductor light emitting element 1051 The current mirror portion 1015 can be controlled so that a large current can flow. On the contrary, when the sensed ambient illuminance is smaller than the illuminance corresponding to the amount of the current flowing through the semiconductor light emitting element, the control unit 1010 controls the semiconductor light emitting element 1051 so that the current flowing through the semiconductor light emitting element 1051 It is possible to control the current mirror portion 1015 so that a small current can flow. The method of controlling the current mirror unit 1051 and specific concepts therefor are the same as those described above, and a detailed description thereof will be omitted.

On the other hand, in the case where the brightness of the semiconductor light emitting device 1051 is controlled by comparing the sensed ambient illuminance with the illuminance corresponding to the amount of current flowing in the current semiconductor light emitting device 1051, The control for varying the pulse voltage can be applied equally. A detailed explanation is given in the above explanation.

Claims (10)

A data electrode line;
A semiconductor light emitting element electrically connected to the data electrode line and supplied with a current supplied through the data electrode line;
A current mirror part electrically connected to the data electrode line and the semiconductor light emitting element and controlling an amount of current supplied to the semiconductor light emitting element through the data electrode line; And
And a control unit controlling the current mirror unit so that an amount of a current supplied to the semiconductor light emitting device is changed based on ambient illuminance. The method according to claim 1,
Wherein,
Driving the current mirror section in one of the first operation mode and the second operation mode based on the ambient illuminance,
Wherein the amount of current supplied to the semiconductor light emitting element in the first operation mode is larger than the amount of current supplied to the semiconductor light emitting element in the second operation mode. 3. The method of claim 2,
Wherein the ambient illuminance corresponding to the first operation mode is larger than the ambient illuminance corresponding to the second operation mode. 3. The method of claim 2,
The control unit controls a current supplied to the data electrode line by a PWM (Pulse Width Modulation) method,
Wherein the pulse voltage in the first operation mode and the pulse voltage in the second operation mode are different from each other. 5. The method of claim 4,
Wherein the pulse voltage in the first operation mode is larger than the pulse voltage in the second operation mode. 5. The method of claim 4,
The amount of current supplied to the semiconductor light emitting element in the first operation mode is larger than the amount of current supplied to the semiconductor light emitting element in the second operation mode,
Wherein the pulse voltage to the first operation mode is larger than the pulse voltage in the second operation mode. The method according to claim 1,
Further comprising an illuminance sensor unit for sensing ambient illuminance,
Wherein,
And controls the amount of current supplied to the semiconductor light emitting device by using the sensing result through the illuminance sensor unit. 8. The method of claim 7,
Wherein,
And controlling the current mirror unit to increase the amount of current supplied to the semiconductor light emitting device when the ambient illuminance is greater than a predetermined reference as a result of the sensing,
Wherein the control unit controls the current mirror unit to reduce an amount of current supplied to the semiconductor light emitting device when the ambient illuminance is smaller than a predetermined reference as a result of the sensing. And a semiconductor light emitting element that receives a current through an electrical connection with a data electrode line,
Sensing ambient illuminance; And
And controlling the current mirror part electrically connected to the data electrode line and the semiconductor light emitting device so that the amount of current supplied to the semiconductor light emitting device increases when the sensed ambient illuminance is larger than the reference illuminance Of the display device. 10. The method of claim 9,
The current supplied to the data electrode line is controlled by a PWM (Pulse Width Modulation) method,
Wherein when the sensed ambient illuminance is greater than the reference illuminance, the pulse voltage increases.

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