KR102332427B1 - Edge Bending Structure Display Having Enhancing White Luminance Distortion At Bended Sides - Google Patents

Abstract

The present invention relates to a display device having a bent side structure, but with improved white luminance distortion of a bent curved portion. In order to achieve the object of the present invention, a display device according to the present invention includes a flat part, a curved part, first data wires, second data wires, first pixels, second pixels, and a data driver. . The curved part is curved and extended in a direction perpendicular to the plane part in one direction of the plane part. The first data lines are disposed on the planar portion. The second data lines are disposed on the curved portion. The first pixels are connected to the first data lines. The second pixels are connected to second data lines. In addition, the data driver applies a first data voltage to the first pixels through the first data line and applies the first data voltage to the second pixels through the second data lines when the same grayscale is expressed in the first pixels and the second pixels. Second data voltages that are greater than the first data voltage and sequentially increase are applied to .

Description

TECHNICAL FIELD [0002] Edge Bending Structure Display Having Enhancing White Luminance Distortion At Bended Sides

The present invention relates to a display device having a bent side structure, but with improved white luminance distortion of a bent curved portion. In particular, the present invention relates to a display device in which a decrease in white luminance that occurs when viewing a curved side from the front by a structure in which left and right side portions are bent toward the bottom surface is improved.

Recently, various flat panel display devices capable of reducing weight and volume, which are disadvantages of a cathode ray tube, have been developed. Such flat panel displays include a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an electroluminescence device (EL). have.

Since the flat panel display device is thin and light in weight, it is widely used as a display means in a mobile communication terminal or a portable information processor. In particular, in portable or mobile devices, there is an increasing demand for a display panel that is thinner, lighter, and consumes less power.

An electroluminescent display device is in the spotlight as a display device most suitable for these needs. The electroluminescent device is broadly classified into an inorganic electroluminescent device and an organic light emitting diode device according to the material of the light emitting layer, and has advantages of fast response speed, high luminous efficiency, luminance and viewing angle by using a self-luminous device that emits light by itself. The organic light emitting diode display has an organic light emitting diode (OLED).

The organic light emitting diode includes an organic electroluminescent compound layer that emits light by an electric field, and a cathode and an anode that face each other with the organic electroluminescent compound layer interposed therebetween. The organic electroluminescent compound layer includes a hole injection layer (HIL), a hole transport layer (HTL), an emission layer (EML), an electron transport layer (ETL), and an electron injection layer (Electron injection layer). layer, EIL). In the OLED, excitons are formed in the excitation process when holes and electrons injected into the cathode electrode and the cathode recombine in the light emitting layer (EML), and light is emitted due to energy from the excitons.

An organic light emitting diode display (OLED) using the characteristics of an organic light emitting diode, which is an electroluminescent device, includes a passive matrix type organic light emitting diode display (PMOLED) and an active matrix. It is roughly classified into an Active Matrix type Organic Light Emitting Diode display (AMOLED) type. In addition, depending on the direction in which light is emitted, there are a top-emission method and a bottom-emission method.

In particular, a liquid crystal display device or a plasma display device has a limit in developing a self-luminous device having high flexibility and elasticity, and thus there is a limit in application as a flexible display device. However, since the organic light emitting diode display device is formed using an organic thin film, interest is being focused on it as an optimal material that can be applied as a flexible display device by using the flexibility and elasticity characteristic of the organic thin film. An active matrix type flexible organic light emitting diode display (AMOLED) displays an image by controlling the current flowing through the organic light emitting diode using a thin film transistor (TFT).

An organic light emitting diode display device (simply referred to as an organic light emitting diode display) will be described with reference to FIG. 1 . 1 is a cross-sectional view schematically showing the structure of an information processing organ employing an ultra-thin organic light emitting diode display. Referring to FIG. 1 , the ultra-thin organic light emitting diode display DIP includes an organic light emitting device layer FL, a back plate BP attached to the base of the organic light emitting device layer FL, and an upper surface of the organic light emitting device layer FL. It has a structure in which a polarizing film (POL) attached to the polarizing film (POL), a touch panel film (TSP) disposed on the polarizing film (POL), and a cover substrate (CV) are sequentially stacked on the touch panel film (TSP).

In order to make the organic light emitting display device ultra-thin, the thickness of the substrate supporting the display device should be thin. However, in order to satisfy the conditions for mass production in a manufacturing line for forming a currently used display device, a thickness of at least 0.5 mm must be maintained. Therefore, in order to mass-produce an ultra-thin organic light emitting display device, a method of first completing a display element on a manufacturing substrate having a thickness of 0.5 mm, separating the substrate, and reattaching the ultra-thin back plate is used.

The organic light emitting device layer FL includes a flexible base layer PI formed on a manufacturing substrate (not shown), a display layer ACT formed on the flexible base layer PI, and an adhesive layer ADH to protect the display layer ACT. and a passivation layer BA bonded on the display layer ACT through the After the organic light emitting device layer FL is completed, the flexible base layer PI of the organic light emitting device layer FL is separated from the manufacturing substrate, and a thinner back plate BP is attached.

The organic light emitting element layer FL is a display area AA in which display elements including a thin film transistor and an organic light emitting layer are disposed for actually displaying image information, and driving the display elements in the periphery of the display area AA. It is divided into a non-display area NA in which driving elements are disposed.

Additional device films for user convenience are further attached on the organic light emitting device layer FL. For example, a polarizing film (POL) may be attached to prevent reflection of external light from interfering with viewing of an image expressed by the display device. In addition, a touch film (TSP) capable of inputting user information by directly touching the screen may be attached. The touch film TSP may include a first touch film TS1 having wiring layers arranged in a horizontal direction and a second touch film TS2 having wiring layers arranged in a vertical direction. Also, the touch film TSP is divided into a display area AA in which an electrode unit for recognizing a user's touch signal is disposed and a non-display area NA in which a driver for processing a signal of the electrode unit is disposed.

In addition, a cover substrate CV for protecting all the display elements is attached to the uppermost layer. The ultra-thin organic light emitting display device thus formed is combined with various information processing devices to make a final product. For example, the organic light emitting display device is coupled to the upper portion of the information processing device as one device using the frame FR. In this case, a part of the frame FT has a structure that covers the upper side portion of the display device. This part is usually the bezel area (BZ). The bezel region BZ is a region where the driving circuit unit is disposed and/or where connecting members for connecting the driving circuit unit and the display panel are installed, and includes the non-display area NA of the organic light emitting diode layer FL.

In order to provide precise and accurate screen information in a portable information device and to directly input user information into a display panel, there is an increasing need to use a larger display panel even in the same area. For this purpose, many efforts are being made to reduce the bezel area (BZ). However, even when high-integration technology is applied, there is a limit to minimizing the bezel area BZ due to the existence of the non-display area NA of the organic light emitting diode display (DIP).

SUMMARY OF THE INVENTION It is an object of the present invention to provide a display device that provides video information in both a flat top display portion and a curved side display portion by bending a non-display area to the side of the area, devised to overcome the above problems. Another object of the present invention is to provide a display device having a structure in which a bezel area is removed by bending a side part, and compensating for white luminance distorted by a curved surface when image information displayed on the side part is viewed from the front. is to provide

In order to achieve the object of the present invention, a display device according to the present invention includes a flat part, a curved part, first data wires, second data wires, first pixels, second pixels, and a data driver. . The curved part is curved and extended in a direction perpendicular to the plane part in one direction of the plane part. The first data lines are disposed on the planar portion. The second data lines are disposed on the curved portion. The first pixels are connected to the first data lines. The second pixels are connected to second data lines. In addition, the data driver applies a first data voltage to the first pixels through the first data line and applies the first data voltage to the second pixels through the second data lines when the same grayscale is expressed in the first pixels and the second pixels. Second data voltages that are greater than the first data voltage and sequentially increase are applied to .

For example, as for the second data voltages, the first second data voltage is applied to the first second data line where the curved portion starts, and the last second data voltage is applied to the last second data line where the curved portion ends. The final second voltage is increased in an arithmetic sequence proportional to the number of second data lines from the first second data voltage.

For example, when the first data voltage is Va, the number of second data lines is M, and the final second data voltage is Vb, the first second data voltage is Va + (Vb-Va)/M, A voltage sequentially increased by (Vb-Va)/M is applied to the second data lines from the first second data line to the last second data line.

For example, the second data lines are divided into a plurality of groups. As for the second data voltages, the first second data voltage is applied to the first group where the curved portion starts, and the last second data voltage is applied to the last group where the curved portion ends. The final second data voltage is a voltage increased in an arithmetic sequence proportional to the number of groups from the first second data voltage.

For example, when the first data voltage is Va, the number of groups is M, and the final second data voltage is Vb, the first second data voltage is Va + (Vb-Va)/M, and in the groups , a voltage sequentially increased by (Vb-Va)/M is applied from the first group to the last group.

For example, the same grayscale is a white grayscale having the maximum brightness value.

The display device according to the present invention can provide video information not only from the front side but also from the side surface of the display device. Accordingly, a wider display area can be secured by removing the bezel area, and the display area can be utilized in various ways. As a result, it is possible to secure a larger large-area display unit in a display device and an information device having the same size. In addition, a higher driving voltage is provided to the area displaying image information on the curved side side than the flat area displaying most of the image information, so that when the side portion is viewed from the front, a decrease in white luminance or color distortion on a white background does not occur. does not In particular, by sequentially providing a high driving voltage from the beginning of the curved surface to the end of the curved surface, it is possible to efficiently compensate for a decrease in white luminance or color distortion of a white background that may occur as the curved surface progresses.

1 is a cross-sectional view schematically showing the structure of an information processing device employing an ultra-thin organic light emitting diode display.
2A to 2D are cross-sectional views schematically illustrating a process of manufacturing a bezel-free display device according to a first embodiment of the present invention.
3A to 3C are cross-sectional views illustrating a situation when image information in a lateral direction is observed from a front direction in a bezel-less display device according to the first and second embodiments of the present invention;
4 is a plan view illustrating a structure of a bezel-less display device having a bent side structure according to a third embodiment of the present invention;
5 is a plan view illustrating a structure of a bezel-less display device having a bent side structure according to a fourth embodiment of the present invention;

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Like reference numerals refer to substantially identical elements throughout. In the following description, if it is determined that a detailed description of a known function or configuration related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, component names used in the following description may be selected in consideration of the ease of writing the specification, and may be different from the component names of the actual product.

<First embodiment>

Hereinafter, a method of manufacturing a bezel-less display device according to a first embodiment of the present invention will be described with reference to FIGS. 2A to 2D . 2A to 2D are cross-sectional views schematically illustrating a process of manufacturing a bezel-free display device according to the first embodiment of the present invention.

A transparent glass substrate (GLS) having a thickness capable of securing sufficient rigidity and supporting force in a manufacturing process using equipment for manufacturing a semiconductor device and a display device including vacuum equipment and transfer equipment is prepared. A sacrificial layer SL is applied on the entire surface of the substrate GLS. The sacrificial layer SL includes an inorganic material, and preferably has a property of decomposing the interfacial bonding force when irradiated with laser light. An organic light emitting device layer FL is formed on the sacrificial layer SL. A polarizing film POL is attached on the substrate GLS on which the organic light emitting device layer FL is formed using a laminating method. Then, a touch film (TSP) capable of inputting user information by directly touching the screen on the polarizing film (POL) is attached. Since the organic light emitting device layer FL, the polarizing film POL, and the touch film TSP may be the same as or similar to those described in the prior art, detailed descriptions thereof will be omitted. A laser beam is irradiated from the back surface of the sacrificial layer SL on the glass substrate GLS using the laser LAS. In particular, the sacrificial layer SL is irradiated by adjusting the focus of the laser light. As a result, the glass substrate GLS and the organic light emitting device layer FL are separated based on the sacrificial layer SL. (Fig. 2a)

When the organic light emitting device layer FL is formed by a thin film process and has a total thickness of about several thousand Å and is separated only as a single layer, it is difficult to perform a subsequent process. However, since the polarizing film (POL) and the touch film (TSP) made of a thin film are laminated on the organic light emitting element layer (FL), it has elasticity even if it is easily bent, so that the characteristics of the elements can be maintained, while the subsequent process is not performed. It is possible to secure enough rigidity to perform sufficient performance. A flexible display panel (FDP) by attaching an organic light emitting device layer (FL), a polarizing film (POL) and a touch film (TSP) separated from the glass substrate (GLS) to a back plate (BP) having flexible properties and a thin thickness ) is completed. The back plate BP has a characteristic of being able to maintain the characteristics of the elements because it has elasticity while being easily bent along with rigidity for protecting the organic light emitting element layer FL. A pressure-sensitive adhesive (PSA) having a property of suppressing the generation of bubbles is applied to the surface of the back plate BP and adhered to the organic light-emitting device layer FL. (Fig. 2b)

By attaching the back plate BP, the completed display panel becomes a flexible display panel FDP having flexibility and elasticity. Since the flexible display panel FDP is easily bent, it can be applied to various types of display devices. According to the present invention, it is possible to provide a display device in which the flexible display panel FDP is mounted on the inner surface of the "U"-shaped cover glass CG in which the side part is slightly bent, so that the upper surface and even the bent side part can be used as a display area. To this end, the entire optical adhesive (OCA) is applied on the surface of the touch film (TSP) and adhered to the inner surface of the cover glass (CG). (Fig. 2c)

As a result, the display panel is distributed not only on the upper surface but also on the side surfaces, so that it is possible to provide a display device having a new structure capable of providing video information not only on the upper surface but also on the side surface. That is, the bezel-free display device having a side bending structure according to the present invention includes a front display area UAA and a side display area SAA. (Fig. 2d)

As described above, a bezel-free display device having a structure in which a partial region of the side is curved may provide main image information in the front direction (①). In addition, incidental image information may be provided in the lateral direction (②). A bezel-free display device in which a portion of a side area is curved has a bezel-free feature, so that the entire front surface of the display device can be used as a display area. In addition, by providing image information for different uses and purposes from the front and side, respectively, it can be applied in various ways.

However, when viewed from the front, the degree of image information provided in the lateral direction is recognized. That is, when viewed from the front, image information displayed on the curved portion corresponding to a certain angle from the beginning of the curved surface may be recognized from the front. However, the part close to the side is not recognized from the front. Rather, it is darkened, and when viewed from the front, the edges are black and the visibility is not good.

<Second embodiment>

Hereinafter, a second embodiment of the present invention will be described with reference to FIGS. 3A to 3C. 3A to 3C are cross-sectional views illustrating a situation when image information in a lateral direction is observed from a front direction in a bezel-less display device according to the first and second embodiments of the present invention. In particular, FIG. 3A is a cross-sectional view illustrating a color luminance degradation region that occurs when the side portion is viewed from the front direction in the bezel-free display device according to the first embodiment of the present invention. 3B and 3C are cross-sectional views illustrating a color luminance degradation region occurring when a side portion is viewed from a front direction in a bezel-free display device according to a second exemplary embodiment of the present invention.

Referring to FIG. 3A , the bezel-less display device having the side-bending structure according to the first embodiment of the present invention includes a front display area UAA and a side display area SAA. The front display area UAA is a planar part, and the side display area SAA is curved and extended in a plane direction perpendicular to the planar part in one direction of the planar part. The side display area SAA is formed of a curved portion. In particular, the side display area SAA has an arc shape corresponding to 1/4 of a circle having a radius of R.

In this case, when the display device is viewed from the front direction, image information displayed on the front display area UAA is recognized with correct color luminance. In addition, when the display device is observed from the side direction, image information displayed on the side display area SAA may be recognized with correct color luminance. However, when the display device is viewed from the front direction, the image information displayed on the side display area SAA may be perceived as distorted in color luminance. In particular, when a white background is displayed, the white luminance is more severely distorted, so that the background and display information cannot be accurately distinguished.

In particular, the white luminance of the background is distorted and not recognized with respect to image information displayed at the beginning of the curved portion, which is the side display area SAA, but the degree of distortion of the white luminance of the background gradually increases toward the end of the curved portion. . As a result, when the bezel-free display device according to the first embodiment of the present invention is viewed from the front, the white background constituting the image information displayed on the edges of both sides gradually appears black, and thus the display information image is distinguished from the background. This causes a dark (or dark: dark) area (DA) that is not properly recognized.

The dark area DA may correspond to a curved portion that exceeds a contact point with the curved surface when the viewing direction line 100 looking at the curved portion SAA from the front is drawn. In order to reduce the dark area DA, it is possible to reduce the degree of curvature of the curved portion SAA to a certain extent. In the second embodiment of the present invention, a bezel-free display device having a bent side structure in which a dark area is reduced in the curved portion SAA is proposed.

Referring to FIG. 3B , it is characterized in that the curved surface portion SAA has a radius of curvature in a vertical direction of R and a radius of a curved surface in a horizontal direction of 2R. In this case, compared with FIG. 3A , the curvature of the curved surface portion SAA becomes gentle. As a result, the dark area DA may be significantly reduced. For example, as shown in FIG. 3B , when the curved portion SAA is viewed from the front direction, the dark area DA, which is the curved portion SAA beyond the contact point where the viewing direction line 100 and the curved surface meet, is The size is smaller than the size of the dark area DA generated in FIG. 3A .

As another example, referring to FIG. 3C , the curved surface portion SAA is characterized in that the radius of the curved surface in the vertical direction has R and the radius of the curved surface in the horizontal direction has 3R. In this case, compared with FIG. 3A , the curvature of the curved surface portion SAA becomes gentle. Moreover, the curved portion SAA of FIG. 3C has a more gentle curvature than the curved portion SAA of FIG. 3B . As a result, the dark area DA may be further significantly reduced. For example, as shown in FIG. 3C , when the curved portion SAA is viewed from the front direction, the dark area DA, which is the curved portion SAA that exceeds the contact point where the viewing direction line 100 and the curved surface meet, is The size is smaller than the size of the dark area DA generated in FIGS. 3A and 3B .

As described above, the dark area DA may be reduced by gently forming the curvature of the curved portion SAA, which is the side display area, in the bezel-less display device having the side bending structure. In order to reduce the dark area DA, it is more advantageous to make the curvature smoother. However, as the curvature is made softer, the meaning of manufacturing the display device by actually bending the side edges decreases. That is, the utilization of separately configuring the side display area SAA to display information different from the front display area UAA may be lost.

<Third embodiment>

Hereinafter, in the third embodiment of the present invention, when the image information displayed in the side display area SAA is viewed from the front even when the curvature of the curved portion SAA is large as shown in FIGS. 3A and 3B, color distortion does not occur. We propose a bezel-free display device having a bent side structure that can be displayed without a display. 4 is a plan view illustrating a structure of a bezel-less display device having a bent side structure according to a third embodiment of the present invention.

Referring to FIG. 4 , a bezel-free display device having a side bending structure according to a third exemplary embodiment includes a front display area UAA and a side display area SAA. The front display area UAA is a flat portion, and the side display area SAA is a curved portion that is curved and extended in a planar direction perpendicular to the planar portion in one direction of the planar portion.

A plurality of front pixels are arranged in a matrix manner in the front display area UAA, which is a flat portion. These front pixels are formed in a pixel area formed by crossing a plurality of planar data lines UDL running in a vertical direction and a plurality of gate wires (not shown) running in a horizontal direction on the substrate SUB. In FIG. 4, only planar data lines (UDLs) are illustrated for convenience.

In order to display image information even on the curved side display area SAA, it may have the same structure as that of the front display area USS. For example, the side pixels PXL are arranged in a matrix manner on the substrate SUB. The side pixels PXL are formed in a pixel area formed by crossing a plurality of curved data lines SDL running in a vertical direction and a plurality of gate wires (not shown) running in a horizontal direction on the substrate SUB. . For convenience, only the curved data lines SDL are illustrated in FIG. 4 , and a portion of the curved portion SSA disposed on one side of the planar portion UAA is enlarged.

Front image information is displayed on the front pixels disposed on the planar part UAA. For example, when displaying full-color image information, a maximum luminance of 100% to a minimum luminance of 0% may be displayed by dividing the desired luminance level. To this end, a data voltage corresponding to the gray level of the display image is applied to the planar data lines UDL disposed on the planar portion UAA. The data voltage applied through the planar data line UDL may be applied to the planar pixel, and a corresponding grayscale may be expressed.

The planar data lines UDL disposed on the planar unit UAA receive a data voltage corresponding to the grayscale of image information to be expressed from the data driving circuit DIC. The curved data lines SDL disposed on the curved portion SAA may also receive a data voltage corresponding to the grayscale of the image information to be expressed from the data driving circuit DIC. The data driving circuit DIC may be configured as a separate integrated circuit separated from the planar data line UDL disposed on the flat portion UAA and the curved data line SDL disposed on the curved portion SAA. Here, a case in which the data driving circuit DIC is configured as one integrated integrated circuit will be described.

When the flat pixels disposed in the planar portion UAA display the same grayscale, the same data voltage is applied to the planar data line UDL. For example, when a white gradation having a gradation value of 100% is to be displayed on any one pixel of the flat unit UAA, 3V, which is a data voltage for representing the maximum brightness, is connected to the flat data line UDL connected to the pixel. supplied through Also, when the same white gradation is to be displayed on other pixels of the planar unit UAA, the same data voltage of 3V is supplied through the planar data line UDL connected to the other pixels. That is, when the same grayscale is expressed in the planar pixels disposed in the planar part UAA, the data driving circuit DIC applies the same data voltage to the corresponding planar pixels through the planar data lines UDL.

Meanwhile, in the curved portion SAA, it is preferable to supply a data voltage value different from that of the flat portion UAA, ie, a compensated curved data voltage, in order to compensate for a decrease in luminance of white, which is mainly used as a background. In particular, it is preferable to sequentially apply the increasing curved data voltage to the adjacent curved data lines SDL in a direction in which the curved surface portion SAA travels along the curved surface.

For example, when the number of curved data lines SDL disposed on the curved portion SAA is 40, the first curved data line SDL1 is disposed at the beginning of the curved portion SAA. In addition, a 40 th curved data line SDL40 is disposed at the end of the curved portion SAA. In this structure, the curved data voltage supplied from the data driving circuit DIC from the first curved data line SDL1 to the 40th curved data line SDL40 is supplied with increasing voltage values in an arithmetic sequence.

More specifically, when the flat pixels disposed in the planar portion UAA display the same grayscale, the same data voltage is applied to the planar data line UDL. On the other hand, when the same gray level is displayed on the curved portion SAA, a brighter gray level is preferably displayed in consideration of color distortion. For example, when a white gradation having a gradation value of 100% is to be displayed on any one pixel of the flat portion USS, a data voltage of 3V for representing the maximum brightness is applied to the flat data line UDL connected to the pixel. supplied through In addition, when a background screen having the same white gradation is to be displayed on the curved portion UAA, a curved data voltage higher than 3V is preferably supplied through the curved data line SDL connected to the curved pixel.

In this case, the curved data voltage preferably has a voltage distribution that increases in proportion to the traveling direction of the curved surface over the entire curved surface SAA. For example, when a white gradation having a gradation value of 100% is displayed on one curved pixel connected to the 40th curved data line SDL40, color distortion occurs most severely when viewed from the front. In consideration of this, it is preferable to apply a voltage higher than 3V representing the white grayscale in the flat portion UAA, 0.5V, which is a compensation voltage capable of maximally compensating for color distortion, to the 40th curved data line SDL40.

Meanwhile, in the first curved data line SDL1 from which the curved portion SAA starts, the grayscale distortion with respect to the white background occurs the least. . For example, when the white gradation voltage of the flat data line UDL is 3V and the white gradation voltage of the 40th curved data line SDL40 having the maximum compensation voltage value is 3.5V, the first curved data line SDL1 is The data voltage for the white gradation voltage becomes {3V + (3.5V - 3V)/40}V. In addition, the curved data voltages therebetween have a distribution that starts from the first curved data line SDL1 and sequentially increases by (3.5V - 3V)/40V.

That is, when the same gradation is expressed in the curved pixels disposed on the curved surface SAA, the data driving circuit DIC applies a sequentially increasing curved data voltage from the curved beginning to the curved ending to the curved data lines ( SDL) to the corresponding curved pixels PXL. At this time, it is preferable that the increasing relationship increases in an arithmetic permutation manner.

For example, when the number of curved data lines SDL is 40, the order corresponds to 40, which is the number of curved data lines SDL. That is, the 40th curved data line SDL40 corresponding to the last order is disposed in the first curved data line SDL1 corresponding to the first order. And the tolerance voltage becomes (maximum compensation voltage / number of curved data lines). That is, in this case, the 'maximum compensation voltage' is 0.5V, which is the difference voltage between the 'gray voltage of the 40th curved data line SDL40' and the 'planar data voltage'. Therefore, the tolerance voltage is 0.5V/40 = 0.125V.

That is, when a white gradation is displayed in the first curved pixel PXL1 connected to the first curved data line SDL1 , 3.125 V is applied to the first curved data line SDL1 by the data driving circuit DIC. When a white gradation is displayed in the second curved pixel PXL2 connected to the second curved data line SDL2 , 3.25 V is applied to the second curved data line SDL1 by the data driving circuit DIC. In the same way, when the 39th curved pixel PXL39 connected to the 39th curved data line SDL39 displays a white gradation, the data driving circuit DIC applies 3.375 V to the 39th curved data line SDL39. When a white gradation is displayed in the 40th curved pixel PXL40 connected to the 40th curved data line SDL40, 3.5V is applied to the 40th curved data line SDL40 from the data driving circuit DIC.

<Fourth embodiment>

Hereinafter, a fourth embodiment of the present invention will be described with reference to FIG. 5 . In the fourth embodiment, when more curved data lines SDL are disposed than in the third embodiment, a structure for effectively compensating for color distortion will be described. 5 is a plan view illustrating a structure of a bezel-less display device having a bent side structure according to a fourth embodiment of the present invention.

Referring to FIG. 5 , a bezel-less display device having a bent side structure according to a fourth embodiment of the present invention includes a front display area UAA and a side display area SAA. The front display area UAA is a flat portion, and the side display area SAA is a curved portion that is curved and extended in a planar direction perpendicular to the planar portion in one direction of the planar portion.

A plurality of front pixels are arranged in a matrix manner in the front display area UAA, which is a flat portion. These front pixels are formed in a pixel area formed by crossing a plurality of planar data lines UDL running in a vertical direction and a plurality of gate wires (not shown) running in a horizontal direction on the substrate SUB.

In the curved side display area SAA, side pixels PXL are arranged on the substrate SUB in a matrix manner. The side pixels PXL are formed in a pixel area formed by crossing a plurality of curved data lines SDL running in a vertical direction and a plurality of gate wires (not shown) running in a horizontal direction on the substrate SUB. .

Front image information is displayed on the front pixels disposed on the planar part UAA. A data voltage corresponding to a gray level of a display image is applied to the planar data lines UDL disposed on the planar portion UAA. The planar data lines UDL disposed on the planar unit UAA receive a data voltage corresponding to the grayscale of image information to be expressed from the data driving circuit DIC.

Side image information is displayed on side pixels disposed on the curved surface SAA. The curved data lines SDL disposed on the curved portion SAA also receive a data voltage corresponding to the grayscale of the image information to be expressed from the data driving circuit DIC. The data driving circuit DIC may be configured as a separate integrated circuit separated from the planar data line UDL disposed on the flat portion UAA and the curved data line SDL disposed on the curved portion SAA.

When the flat pixels disposed in the planar portion UAA display the same grayscale, the same data voltage is applied to the planar data line UDL. For example, when the same grayscale is expressed in the planar pixels disposed in the planar part UAA, the data driving circuit DIC applies the same data voltage to the corresponding planar pixels through the planar data lines UDL.

Meanwhile, in the curved portion SAA, it is preferable to supply a data voltage value different from that of the flat portion UAA, ie, a compensated curved data voltage, in order to compensate for a decrease in luminance of white, which is mainly used as a background. In particular, it is preferable to sequentially apply the increasing curved data voltage to the adjacent curved data lines SDL in a direction in which the curved surface portion SAA travels along the curved surface.

In particular, when the number of curved data lines SDL disposed on the curved portion SAA is 160, which is much more than that of the third embodiment, the curved data voltages divided by 160 steps are applied to the 160 curved data lines SDL. Authorization is quite complex. Accordingly, it is preferable to divide the curved data lines SDL into a series of groups and apply the curved data voltages divided into small increments.

For example, 160 curved data lines SDL may be grouped into 40 groups by grouping 4 each. As a result, the curved data lines SDL of the first group GR1 are disposed at the beginning of the curved portion SAA. In addition, the curved data lines SDL of the fortieth group GR40 are disposed at the end of the curved portion SAA. In this structure, the curved data voltages supplied from the data driving circuit DIC from the first group GR1 to the 40th group GR40 are supplied with increasing voltage values in an arithmetic sequence method.

More specifically, when the flat pixels disposed in the planar portion UAA display the same grayscale, the same data voltage is applied to the planar data line UDL. On the other hand, when the same gray level is displayed on the curved portion SAA, a brighter gray level is preferably displayed in consideration of color distortion. For example, when a white gradation having a gradation value of 100% is to be displayed on any one pixel of the flat unit UAA, 3V, which is a data voltage for representing the maximum brightness, is connected to the flat data line UDL connected to the pixel. supplied through In addition, when a background screen having the same white gradation is to be displayed on the curved portion UAA, a curved data voltage higher than 3V is preferably supplied through the curved data line SDL connected to the curved pixel.

In this case, the curved data voltage preferably has a voltage distribution that increases in proportion to the traveling direction of the curved surface over the entire curved surface SAA. For example, when a white gradation having a gradation value of 100% is displayed on any one curved pixel connected to the 40th group GR40, color distortion occurs most severely when viewed from the front. In consideration of this, it is preferable to apply a voltage that is increased by 0.5V, which is a compensation voltage capable of maximally compensating for color distortion, from 3V representing a white gradation in the flat portion UAA to the 40th group GR40.

Meanwhile, in the first group GR1 where the curved portion SAA starts, grayscale distortion with respect to the white background occurs least, so that it is preferable to apply a voltage having only the minimum compensation voltage higher than that of the planar data line UDL. For example, when the white gradation voltage of the planar data line UDL is 3V and the white gradation voltage of the 40th group GR40 having the maximum compensation voltage value is 3.5V, the white gradation voltage is applied to the first group GR1. The data voltage for this becomes {3V + (3.5V - 3V)/40}V. And the data voltages supplied to the groups therebetween have a distribution that sequentially increases by (3.5V - 3V)/40V starting from the first group GR1.

That is, when the same gradation is expressed in the curved pixels disposed on the curved surface SAA, the data driving circuit DIC applies a sequentially increasing curved data voltage from the curved beginning to the curved ending to the curved data lines ( SDL) to the corresponding curved pixels PXL. At this time, it is preferable that the increasing relationship increases in an arithmetic permutation manner.

For example, when the number of curved data lines SDL is 160 and the number of curved data lines SDL is divided into 40 groups by grouping them by 4, the order corresponds to 40, which is the number of groups in which the curved data lines SDL are grouped. That is, the 160 curved data lines SDL are divided and arranged from the first group GR1 corresponding to the first order to the 40th group GR40 corresponding to the last order. And the tolerance voltage becomes (maximum compensation voltage / number of groups). That is, in this case, the 'maximum compensation voltage' is 0.5V, which is the difference voltage between the 'gray voltage of the 40th group GR40' and the 'planar data voltage'. Therefore, the tolerance voltage is 0.5V/40 = 0.125V.

That is, when a white gradation is displayed in the first curved pixels PXL1 to PXL4 connected to the first group GR1 , 3.125 V is applied to the curved data lines SDL corresponding to the first group GR1 in the data driving circuit DIC. to authorize When a white gradation is displayed in the second curved pixels PXL5 to PXL8 connected to the second group GR2, 3.25 V is applied to the curved data lines SDL corresponding to the second group GR2 in the data driving circuit DIC. . In the same way, when a white gradation is displayed in the 39th curved pixels PXL153 to PXL156 connected to the 39th group GR39, the curved data lines corresponding to the 39th group GR39 in the data driving circuit DIC ( SDL) to 3.375V. When a white gradation is displayed in the 40th curved pixels PXL157 to PXL160 connected to the 40th group GR40, 3.5V is applied to the curved data lines SDL corresponding to the 40th group GR40 in the data driving circuit DIC. to authorize

Those skilled in the art from the above description will be able to see that various changes and modifications can be made without departing from the technical spirit of the present invention. Accordingly, the present invention should not be limited to the contents described in the detailed description, but should be defined by the claims.

BP: Back plate CV: Cover substrate
FL: organic light emitting device layer PI: flexible base layer
ACT: display layer ADH: adhesive layer
BA: protective layer POL: polarizing film
TSP: touch panel film TS1: first touch panel film
TS2: second touch panel film FR: frame
AA: display area NA: non-display area
TSL: Touch thin film layer CG: Cover glass
FL: flexible display film FDP: flexible display panel
DA: dark area DIC: data drive circuit
UDL: flat data wiring SDL: curved data wiring
PXL: curved pixel

Claims (6)

flat part;
a curved portion extending in a direction perpendicular to the flat portion in one direction of the flat portion;
a plurality of first data lines disposed on the planar portion;
a plurality of second data lines disposed on the curved portion;
first pixels connected to the first data lines;
second pixels connected to the second data lines; and
When the same grayscale is expressed in the first pixels and the second pixels, a first data voltage is applied to the first pixels through the first data line, and the second pixel through the second data lines and a data driver for applying second data voltages that are greater than the first data voltage and sequentially increase;
The second data voltages are
a first second data voltage is applied to the first second data line from which the curved portion starts;
A final second data voltage is applied to the final second data line where the curved portion is terminated,
The final second data voltage is a voltage increased from the first second data voltage in an arithmetic sequence proportional to the number of the second data lines.
delete The method of claim 1,
The first data voltage is Va;
The number of the second data lines is M,
When the final second data voltage is Vb,
The first second data voltage is Va + (Vb-Va)/M,
A voltage sequentially increased by (Vb-Va)/M is applied to the second data lines from the first second data line to the last second data line.
flat part;
a curved portion extending in a direction perpendicular to the flat portion in one direction of the flat portion;
a plurality of first data lines disposed on the planar portion;
a plurality of second data lines disposed on the curved portion;
first pixels connected to the first data lines;
second pixels connected to the second data lines; and
When the same grayscale is expressed in the first pixels and the second pixels, a first data voltage is applied to the first pixels through the first data line, and the second pixel through the second data lines and a data driver for applying second data voltages that are greater than the first data voltage and sequentially increase;
The second data lines are divided into a plurality of groups,
The second data voltages are
A first second data voltage is applied to the first group where the curved portion starts,
A final second data voltage is applied to the last group to which the curved part ends,
The final second data voltage is a voltage that is increased in an arithmetic sequence proportional to the number of groups from the first second data voltage.
5. The method of claim 4,
The first data voltage is Va;
The number of the group is M,
When the final second data voltage is Vb,
The first second data voltage is Va + (Vb-Va)/M,
A display device in which a voltage sequentially increased by (Vb-Va)/M is applied to the groups from the first group to the last group.
6. The method of any one of claims 1 or 3 to 5,
The same grayscale is a white grayscale having a maximum brightness value.

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