TWI723530B - Display device and the driving method thereof - Google Patents

Abstract

A display device including backlight module, light valve groups located on the backlight module is provided, and every light group includes sub pixels. The backlight module includes light emitting arrays, and the light emitting array includes light emitting areas disposed along a first direction. The position of every light emitting arrays is corresponded to the position of one of the light valve groups, and the sub pixels of the light valve group are disposed along a second direction, and the first direction and the second direction are not parallel. When the light emitting areas of the light emitting array is emitting light, the illuminating light of every light emitting areas can illuminate multiple sub pixels. A driving method of the display device is also provided.

Description

Display device and driving method thereof

The present invention relates to a display device and a driving method thereof, in particular to a display device with a direct-lit backlight and a driving method thereof.

In the existing display technology, the related technology of Light Emitting Diode (LED) has become one of the protagonists. Technologies occupying a major position in the light-emitting diode market include liquid crystal display (LCD) technology with light-emitting diodes as backlights and organic light-emitting diode (OLED) display technology. People continue to Improve these display technologies in terms of picture contrast, color quality, and picture brightness.

For example, when a light-emitting diode is used as a backlight module for a surface light source, the liquid crystal display technology will affect the appearance of black due to phenomena such as light leakage, and even affect the overall contrast of the screen. In addition, in order to make the displayed image more detailed, the existing device makes a miniaturized light-emitting diode to individually provide illumination for each pixel. However, since the current level of the light-emitting diode and the control voltage transmitted by the drive circuit of the light-emitting diode present a non-linear relationship, it is difficult to adjust by the control voltage signal. If the miniaturized light source corresponding to each sub-pixel is increased, the complexity of the overall circuit will increase with the number of miniature light-emitting diodes. Therefore, when the display device uses miniaturized light-emitting diodes as the light source of the display pixels, it is difficult for the display device to increase its resolution due to the above-mentioned problems. Therefore, how to make a better display technology with light-emitting diodes is one of the main problems that the display technology wants to solve.

The object of the present invention is to provide a display device, which can provide a variety of different colors and brightness in each pixel, and provide a display screen with richer colors.

The display device of the present invention includes a backlight module and a plurality of display pixels on the backlight module, and each display pixel includes a plurality of sub-pixels.

The backlight module includes a plurality of light-emitting arrays, and the light-emitting array includes a plurality of light-emitting areas arranged along a first direction. The position of each light-emitting array corresponds to the position of one of the display pixels, and the sub-pixels of the display pixels are arranged along the second direction, and the first direction and the second direction are not parallel. When the light-emitting areas in the light-emitting array illuminate light beams, the illuminating light beams provided by each light-emitting area can illuminate multiple sub-pixels.

The display device of the present invention includes a plurality of display units, and each display unit includes a light-emitting array and display pixels including a plurality of sub-pixels, and these sub-pixels of the display pixels are arranged on the light-emitting array.

The light emitting array includes a plurality of light emitting regions arranged along a first direction, and the sub-pixels are arranged along a second direction, and the first direction and the second direction are not parallel to each other. When the light-emitting areas in the light-emitting array provide illumination light beams, the illumination light beams provided by each light-emitting area can illuminate multiple sub-pixels.

The method for driving a display device of the present invention includes providing grayscale data including a plurality of grayscale values; obtaining the maximum value of these grayscale values in each grayscale data; generating a light-emitting control signal according to the maximum value; providing light-emitting control Signal to one of the light-emitting arrays to determine the number of light-emitting areas in the light-emitting array; and provide gray-scale data to a plurality of sub-pixels corresponding to the light-emitting array, and these sub-pixels are adjusted according to the gray-scale values in the received gray-scale data Transmittance.

With the above-mentioned display pixels, the display device of the present invention can have a good performance in the details of color and brightness, and thereby provide a detailed display screen.

A, B, C: area

d1, d2: direction

S: display surface

100: display device

110: display unit

111: sub-pixel

111G: display pixels

113: Light Valve

115: color filter

120: luminous array

120M: backlight module

121: light-emitting area

130: timing control circuit

131: The first data drive circuit

132: Second data drive circuit

133: The first data line

134: The second data line

135: LED

136, 139: Switch

137, 138: Power cord

1 is a schematic diagram of a display device according to a first embodiment of the present invention; FIGS. 2A to 2C are exploded schematic diagrams of a display pixel according to the first embodiment of the present invention; FIG. 3 is a schematic top view of a display pixel according to the first embodiment of the present invention 4A is a schematic flowchart of the driving method of the display device according to the first embodiment of the present invention; FIG. 4B is a system schematic diagram of the display device according to the first embodiment of the present invention.

The display device provided by the present invention can be applied to, for example, computers, televisions, advertising walls, etc. as display screens, and can also be applied to portable devices such as tablet computers and smart phones. FIG. 1 is a schematic diagram of a display device 100 according to a first embodiment of the present invention. For clear description, the partial elements are omitted in the partial area of the display device 100, and the elements above sub-pixels are omitted in area A. The area B omits the elements above the light-emitting array, and the area C enlarges the area A and the area B. The relative positions of the elements in the display device 100 of this embodiment will be clearly described below with reference to these schematic diagrams.

The display device 100 of the first embodiment of the present invention may provide a picture on the display surface S, and the picture is composed of a plurality of display pixels 111G. Each display pixel 111G includes a plurality of sub-pixels 111, and the light-emitting array 120 is located under the sub-pixels 111. In other words, the distribution area of these display pixels 111G corresponds to the position of the light-emitting array 120, which is located at a position that can illuminate the sub-pixels 111 of the display pixel 111G, and serves as the light source of the sub-pixels 111 in the display pixel 111G.

For example, the light-emitting arrays 120 may jointly form a backlight module 120M, and the light source is provided below the plane where the sub-pixels 111 are arranged, that is, the backlight module 120M provides a direct light source. However, the present invention is not limited to these implementations of the light-emitting array 120, and those with ordinary knowledge in the art can use other implementations to provide a light source with the same effect in the display device 100.

Referring back to FIG. 1, the light-emitting array 120 of the first embodiment of the present invention includes a plurality of light-emitting areas 121, and the arrangement of the light-emitting areas 121 in each display pixel 111 is different from the arrangement of the sub-pixels 111. The light-emitting regions 121 are arranged along the first direction d1, and the sub-pixels 111 are arranged along the second direction d2. In other words, the first direction d1 and the second direction d2 are different, and they are not parallel to each other.

For example, the sub-pixel 111 of this embodiment is composed of a light valve (Light valve) and a color filter (Color filter), wherein the light valve is preferably a transmissive light valve such as a liquid crystal (Liquid Crystal). . The light-emitting area 121 is, for example, formed by the light-emitting surface of a light-emitting diode. Preferably, the light-emitting area 121 of this embodiment is composed of, for example, a mini or micro LED (mini or μLED), a light-emitting diode, or an organic light-emitting diode. The present invention is not limited to the element types of the light-emitting area 121 and the sub-pixel 111, and other elements that can provide the same optical effect can be used in other embodiments.

On the other hand, referring to the partial enlarged view in FIG. 1, the number of these sub-pixels 111 in the display pixel 111G of this embodiment is taken as an example, that is, every three sub-pixels 111 are formed in the display device 100 corresponding to The display pixels 111G of the light-emitting array 120, and the number of light-emitting regions 121 of the light-emitting array 120 is also taken as an example. The three sub-pixels 111 in each display pixel 111G each have a different chrominance. It preferably corresponds to the three optical primary colors used for display. Furthermore, the display device of this embodiment includes a plurality of display units 110, and each display unit 110 includes a display pixel 111G and a light-emitting array 120. In each display unit 110, the distribution area of the display pixels 111G overlaps the distribution area of the light-emitting array 120, and the sub-pixels 111 in the upper layer and the light-emitting areas 121 in the lower layer are arranged along different directions.

To further clarify the description, a single display pixel will be used to illustrate the detailed features of the display device of this embodiment. Furthermore, the light-emitting array 120 of this embodiment can present the brightness of the display unit 110 with a variety of different lighting effects, that is, the gray level. The following will explain in order.

2A-2C are exploded schematic diagrams of the display unit and the light-emitting array in the first embodiment of the present invention. 2A, the light beam provided by the light-emitting area 121 of the light-emitting array 120 can illuminate the sub-pixels 111. Taking the sub-pixel 111 indicated in the figure as an example, the sub-pixel 111 includes a light valve 113 such as a liquid crystal and a color filter 115, and the illuminating light beam L from the light-emitting area 121 passes through these elements in sequence.

When the light-emitting array 120 lights up only one light-emitting area 121, only a part of each sub-pixel 111 will be illuminated by the illumination beam L, so the display unit 110 can present a gray scale with a lower brightness. In other words, the light-emitting array 120 that lights up a single light-emitting area 121 determines in advance that the display unit 110 should present a gray scale with a lower brightness, and then the sub-pixel 111 is used to further control the color and the transmittance of the illumination beam L to further improve The type of color and the number of grayscales when the display unit 110 displays a low-brightness screen.

2B, when the light-emitting array 120 only lights up two light-emitting areas 121, the light valve 113 and color filter 115 of each sub-pixel 111 will have a larger area illuminated by the illuminating beam L, so the display unit 110 can It presents gray scales with higher brightness.

2C, when the light-emitting array 120 lights up all the light-emitting areas 121, the light valve 113 and the color filter 115 of the sub-pixel 111 have the largest area illuminated by the illumination beam L, so the display unit 110 can present the gray scale with the highest brightness. .

In other words, the light-emitting array 120 can initially control the gray scale of the display unit 110 by controlling the number of light-emitting regions 121 to be lit, and then further control the color and light transmittance by the sub-pixel 111. Therefore, the display device 100 uses these display units 110 to provide an appropriate light source for the light-emitting array 120 of each display unit 110 whether it is to provide a low, medium or high brightness screen. By further controlling the light transmittance of the sub-pixels 111, the display unit 110 can greatly increase the number of gray scales and colors that the display device 100 can provide.

In other words, with the light-emitting arrays 120 proposed in the present invention, the gray scale of the image screen can be controlled by the display pixels 111G such as liquid crystals, and can also be controlled by the light-emitting areas 121 of each light-emitting array 120 in the backlight module 120M. The number of lights to adjust the backlight intensity, and further adjust the grayscale of the screen.

The following describes the display device of this embodiment from another perspective. FIG. 3 is a schematic diagram of the display unit 110 of the first embodiment of the present invention drawn from a top angle, in which the elements above the light-emitting array 120 are omitted. 3, in the light-emitting array 120 of this embodiment, the light-emitting area 121 emits an illuminating light beam from a light-emitting surface. Furthermore, FIG. 3 is a schematic diagram based on the above-mentioned light-emitting surface, in which the light-emitting areas 121 are arranged along the first direction d1, and the light-emitting surfaces of the light-emitting areas 121 are also substantially distributed on the light-emitting surface.

The above-mentioned display pixels are arranged on the light-emitting areas 121, and the area 111A where the plurality of sub-pixels 111 of the display pixels are projected on the light-emitting surface overlaps and intersects with the distribution areas of the light-emitting areas 121. For example, the projection area 111A of each sub-pixel 111 on the light-emitting surface overlaps the distribution area of the three light-emitting areas 121, so each sub-pixel 111 (refer to the projection area 111A) can form, for example, three sub-regions 111B (marked in the figure). One of them), the sub-pixel 111 corresponding to the sub-region 111B can receive light from one of the light-emitting regions 121, and the entire sub-pixel 111 can receive light from different light-emitting regions in different regions. Therefore, the overall brightness of the sub-pixel 111 can be determined by determining the number of light-emitting regions 121 to be lit.

The shape of the light-emitting areas 121 of this embodiment is a rectangle with long sides perpendicular to the first direction d1, and the shape of the sub-pixels 111 that straddle the light-emitting areas 121 is a rectangle with long sides perpendicular to the second direction d2, and A plurality of rectangular or square sub-regions 111B are formed on the sub-pixel 111. Furthermore, these sub-regions 111B have, for example, the same area size, so that good hierarchical brightness control can be provided in the display unit 110.

However, the present invention is not limited to the shape of the light-emitting area 121 and the sub-pixel 111 described above. In other embodiments, the sub-pixels can be formed in other shapes, and the light-emitting area can be formed in another shape to illuminate these sub-pixels at the same time. On the other hand, in the display unit 110 of the first embodiment of the present invention, the arrangement direction d1 of the light-emitting regions 121 is perpendicular to the arrangement direction d2 of the sub-pixels 111, so that the aforementioned sub-regions 111B having the same area size are preferably formed. To provide good stage brightness control. However, the present invention is not limited to this. In other embodiments, the arrangement direction of the light-emitting area 121 and the arrangement direction of the sub-pixels 111 can be arranged at other angles. Those skilled in the art can follow the shape or display of the light-emitting area 121 and the sub-pixel 111. The demand for pixels adjusts the above-mentioned arrangement direction.

Furthermore, the intensity of the illumination beams emitted by the light-emitting areas 121 of this embodiment is similar, so the light-emitting areas 121 in the light-emitting array 120 are interchangeable. By controlling the number of light-emitting regions 121 in the light-emitting array 120, the brightness range of the display unit 110 can be adjusted.

The driving method of the display device proposed by the present invention will be further described below. Please refer to the flowchart of the driving method shown in FIG. 4A. The display device of the first embodiment of the present invention first provides a gray-scale data (step S1), and the gray-scale data can control one of the above-mentioned display pixels. The grayscale data includes a plurality of grayscale values, and these grayscale values can individually control the light transmittance of each sub-pixel of the display pixel. The gray scale value of this embodiment, for example, has a positive correlation with the light transmittance of the sub-pixel, but the invention is not limited to this.

On the other hand, the grayscale value with the largest value in the grayscale data is taken out (step S2), and a light emission control signal is generated according to the grayscale value (step S3). For example, when the light-emitting array of the display pixel has three light-emitting regions, the numerical range of the gray scale value will be divided into three sections, and the three sections each correspond to one, two, and three light-emitting regions. Luminous control signal. Therefore, after obtaining the maximum gray-scale value in the gray-scale data, the corresponding light-emitting control signal is provided according to which interval the gray-scale value falls in, so as to control the number of light-emitting regions in the display pixel.

In other words, the display device of this embodiment determines the light emission control signal according to the sub-pixel with the greatest brightness requirement among the display pixels. For example, the value range of the gray scale value for controlling the light transmittance of the sub-pixel is, for example, between 0 and 255, and the light emission control signal can be determined, for example, according to the following rule: when the gray scale value in the gray scale data has the maximum value When it falls within the range of 0 to 155, the light-emitting control signal can light up one light-emitting area; when the maximum value of the gray scale value falls within the range of 156 to 212, the light-emitting control signal can light up the two light-emitting areas; When the maximum value of the step value falls within the range of 213 to 255, the light-emitting control signal can light up the three light-emitting areas. According to the above rules, each gray scale value can correspond to a light emission control signal.

On the other hand, please also refer to the system schematic diagram shown in FIG. 4B. The grayscale data of the display device 100 is transmitted to the first data driving circuit 131 through, for example, a timing control circuit 130 (Timing controller), and the first data driving circuit 131 It is transmitted to the sub-pixels of each display pixel via the first data line 133. At the same time, the light-emitting control signal generated according to the gray-scale data is also transmitted to the second data driving circuit 132 via the timing control circuit 130, and the second data driving circuit 132 transmits the light-emitting control signal to each display pixel via the second data line 134. Light emitting area 121 (step S4). In other words, when a grayscale data is to be provided to a display unit, the first data driving circuit 131 can transmit the grayscale data to the display pixels through the first data line 133; the second data driving circuit 132 can transmit the grayscale data to the display pixels through the first data line 133; The second data line 134 transmits the light-emitting control signal to the light-emitting array of the display pixels.

Please refer to the partial enlarged view in FIG. 4B. The light-emitting area 121 of this embodiment is provided by a light-emitting diode 135, for example, and the switch 136 connected to the second data line 134 is connected to the power line of the light-emitting diode 135. Switch 139 between 137 and 138. Therefore, the grayscale data can simultaneously control the light transmittance of the sub-pixels in a display pixel, and at the same time can control the number of light-emitting areas in the display pixel, thereby providing a good picture.

Furthermore, the display device of this embodiment can perform gamma correction on the maximum value after obtaining the maximum value of the grayscale value, for example, by correcting the curve of Gamma 2.2 to obtain To a maximum correction value. Then, according to the maximum correction value, a light-emitting control signal is generated to control the number of light-emitting regions in the light-emitting array.

For example, the relationship between the maximum value of the grayscale value and the maximum value of the correction is as follows: Y (maximum value of the correction)=A×X ^2.2 where A is a constant and X is the maximum value of the grayscale value. The maximum value of the gray scale value can be converted into the maximum value of the correction by the above-mentioned relationship, and then the light emission control signal is determined according to the value of the maximum value of the correction. Therefore, the display device of this embodiment can provide a display screen most suitable for human vision through the above-mentioned driving method.

In summary, the display device of the present invention can control the brightness of the illumination beam in advance through the above-mentioned light-emitting array, and then subdivide the light transmittance through the sub-pixels. In other words, the number of light-emitting regions in the light-emitting array is matched with the light transmittance control of the sub-pixels, and the display device can greatly improve the brightness and color details. The driving method of the display device of this embodiment can directly determine the number of light-emitting regions in the light-emitting array corresponding to each sub-pixel according to the gray-scale data to be provided to the sub-pixels, and therefore can be based on the existing display device applications. Grayscale data to further provide a more vivid and detailed display screen.

d1, d2‧‧‧direction

110‧‧‧Display unit

111‧‧‧Sub-pixel

111G‧‧‧display pixels

113‧‧‧Light valve

115‧‧‧Color filter

120‧‧‧Lighting Array

121‧‧‧Light-emitting area

Claims (9)

A display device includes: a plurality of display units, each of the display units includes: a light-emitting array including a plurality of light-emitting areas arranged along a first direction; and a display pixel arranged on the light-emitting array; wherein, The display pixel includes a plurality of sub-pixels, the plurality of sub-pixels are arranged in a second direction, the second direction is not parallel to the first direction, and each of the light-emitting areas provides an illuminating light beam to illuminate all the plurality of sub-pixels of the display pixel, And each sub-pixel has a plurality of sub-areas, and the sub-areas in the same sub-pixel respectively receive the illumination light beams generated by different light-emitting areas in the corresponding light-emitting array. As for the display device described in item 1 of the scope of patent application, in each of the sub-pixels, the areas of the plurality of sub-regions are substantially the same. The display device according to claim 1, wherein in each display unit, the plurality of light-emitting areas of the light-emitting array emit the illumination beam from a light-emitting surface; the plurality of sub-pixels are projected onto the area of the light-emitting surface It overlaps and intersects with the area where the plurality of light-emitting areas are distributed on the light-emitting surface, and the area where each sub-pixel is projected onto the light-emitting surface overlaps with the area where the plurality of light-emitting areas are distributed on the light-emitting surface. As for the display device described in claim 1, wherein the light-emitting regions are formed in a rectangular shape and each has a first long side perpendicular to the first direction; the sub-pixels are formed in a rectangular shape and each has a second The long side is perpendicular to the second direction; each of the sub-pixels spans above the plurality of light-emitting regions. The display device described in item 1 of the scope of patent application, wherein the first direction and the second direction are They are perpendicular to each other in nature. A method for driving a display device according to any one of items 1 to 5 of the scope of the patent application, comprising: providing a gray-scale data, the gray-scale data includes a plurality of gray-scale values; in each of the gray-scale data Obtain the maximum value of the plurality of gray scale values; generate a light-emitting control signal according to the maximum value; provide the light-emitting control signal to one of the plurality of light-emitting arrays, and determine the light-emitting area in the light-emitting array And providing the gray-scale data to the plurality of sub-pixels corresponding to the light-emitting array, and the plurality of sub-pixels adjust the transmittance according to the plurality of gray-scale values in the received gray-scale data. According to the driving method described in item 6 of the scope of patent application, the step of determining the light-emitting quantity signal further includes: performing gamma correction on the maximum value to generate a maximum correction value; and determining the maximum value according to the correction maximum value. Luminous control signal. For the driving method described in item 6 of the scope of patent application, the step of determining the light-emitting quantity signal further includes: determining a plurality of numerical intervals in the grayscale value receiving range of the plurality of sub-pixels, and the plurality of numerical intervals correspond to different values. The light-emitting control signal; wherein when the light-emitting control signal is determined, the light-emitting control signal is determined according to the value interval to which the maximum value belongs. According to the driving method described in item 6 of the scope of patent application, the transmittance adjusted by the plurality of sub-pixels according to the received gray scale value is positively correlated with the gray scale value.

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