技术领域technical field
本发明涉及一种显示装置及其调光方法，特别是涉及可以改变驱动晶体管的临界电压的一种显示装置及其调光方法。The invention relates to a display device and a dimming method thereof, in particular to a display device capable of changing the critical voltage of a driving transistor and a dimming method thereof.
背景技术Background technique
随着电脑、手机、电视机等各种影音媒体设备的普及，用来呈现图像画面的显示装置也越来越广泛地应用于生产及生活中。于一般有机发光二极管（OrganicLightEmissionDiode,OLED）显示装置中，利用多个晶体管来控制与驱动发光二极管，使得每一个发光二极管能够发射出适当的亮度。With the popularization of various audio-visual media equipment such as computers, mobile phones, and televisions, display devices for presenting images are more and more widely used in production and life. In a general organic light emitting diode (Organic Light Emission Diode, OLED) display device, a plurality of transistors are used to control and drive the light emitting diodes, so that each light emitting diode can emit an appropriate brightness.
举例来说，图1示出了现有技术的OLED显示装置的电路示意图。如图1所示，显示装置9具有开关晶体管90、电容92、驱动晶体管94以及发光二极管96。开关晶体管90受控于扫描线Scan而选择性地将数据线Data上的灰阶电压储存至电容92中，藉以调整驱动晶体管94所输出的驱动电流。然而，不同的晶体管于出厂时的半导体特性（例如临界电压）都存在着误差，尽管可以提供相同的灰阶电压至驱动晶体管94，但驱动晶体管94用以驱动发光二极管96的驱动电流不会完全相同。For example, FIG. 1 shows a schematic circuit diagram of an OLED display device in the prior art. As shown in FIG. 1 , the display device 9 has a switching transistor 90 , a capacitor 92 , a driving transistor 94 and a light emitting diode 96 . The switch transistor 90 is controlled by the scan line Scan to selectively store the grayscale voltage on the data line Data into the capacitor 92 , so as to adjust the driving current output by the driving transistor 94 . However, there are errors in the semiconductor characteristics (such as threshold voltage) of different transistors when they leave the factory. Although the same grayscale voltage can be provided to the driving transistor 94, the driving current used by the driving transistor 94 to drive the light-emitting diode 96 will not be completely same.
从显示画面来看，驱动电流的差异会使画面亮度分布不均匀（mura效应），而影响着使用者的观影质量。为了因应画面亮度分布不均问题，需要增加每个像素组内的电路架构以补偿驱动电流差异，但是额外的电路架构会导致像素开口率降低。因此，业界需要一种新的显示装置，而所述显示装置不需大量增加每个像素组内的如何以简单的电路架构，即可根据显示画面的亮度分布情况而调整其中平均化的发光二极管的驱动电流是未来的设计趋势。From the perspective of the display screen, the difference in driving current will make the brightness distribution of the screen uneven (mura effect), which will affect the viewing quality of the user. In order to cope with the problem of uneven brightness distribution of the screen, it is necessary to increase the circuit structure in each pixel group to compensate for the difference in driving current, but the additional circuit structure will lead to a decrease in the pixel aperture ratio. Therefore, the industry needs a new display device, and the display device does not need to increase a lot in each pixel group, and how to use a simple circuit structure to adjust the averaged light-emitting diodes according to the brightness distribution of the display screen The drive current is the future design trend.
发明内容Contents of the invention
有鉴于此，本发明在于提出一种显示装置，所述显示装置中的驱动晶体管改成四端元件，使得驱动晶体管可以依据补偿电压的大小以调变临界电压的数值，藉此调整输出的驱动电流以改变发光二极管的亮度。In view of this, the present invention proposes a display device in which the drive transistor is changed into a four-terminal element, so that the drive transistor can adjust the value of the threshold voltage according to the magnitude of the compensation voltage, thereby adjusting the output drive current to change the brightness of the LED.
本发明实施例提供一种显示装置，所述显示装置具有发光二极管以及驱动模块。所述驱动模块用以驱动发光二极管，且驱动模块包括第一开关电路、第二开关电路以及驱动晶体管。第一开关电路选择性地将灰阶电压写入第一电容，第二开关电路选择性地将补偿电压写入第二电容。驱动晶体管分别耦接发光二极管、第一电容与第二电容，且驱动晶体管受控于灰阶电压与补偿电压，据以调整输出给发光二极管的驱动电流。其中，灰阶电压调整驱动晶体管的栅极与源极电压差，且补偿电压调整驱动晶体管的临界电压。An embodiment of the present invention provides a display device, the display device has a light emitting diode and a driving module. The drive module is used to drive the light emitting diode, and the drive module includes a first switch circuit, a second switch circuit and a drive transistor. The first switch circuit selectively writes the grayscale voltage into the first capacitor, and the second switch circuit selectively writes the compensation voltage into the second capacitor. The driving transistor is respectively coupled to the light emitting diode, the first capacitor and the second capacitor, and the driving transistor is controlled by the gray scale voltage and the compensation voltage, so as to adjust the driving current output to the light emitting diode. Wherein, the grayscale voltage adjusts the voltage difference between the gate and the source of the driving transistor, and the compensation voltage adjusts the threshold voltage of the driving transistor.
于本发明一实施例中，当发光二极管的亮度低于第一门限值时，补偿电压是用以降低驱动晶体管的临界电压，据以增加驱动电流，而当发光二极管的亮度高于第二门限值时，补偿电压是用以提高驱动晶体管的临界电压，据以减少驱动电流。在此，所述多组像素组以图像获取装置拍摄画面，并经由处理装置判断于图像获取装置拍摄到的画面中，每一组像素组中的发光二极管的亮度是否低于第一门限值或者高于第二门限值。另外，第一开关电路与第二开关电路为开关晶体管，第二开关电路耦接补偿数据线，补偿数据线用以传输补偿控制模块所输出的补偿电压，且补偿控制模块依据处理装置的判断结果调整补偿电压。其中，第一开关电路耦接灰阶数据线，灰阶数据线用以传输灰阶控制模块所输出的灰阶电压，且第一开关电路与第二开关电路受控于同一扫描线而同时导通或截止。In one embodiment of the present invention, when the brightness of the light emitting diode is lower than the first threshold value, the compensation voltage is used to reduce the threshold voltage of the driving transistor, thereby increasing the driving current, and when the brightness of the light emitting diode is higher than the second threshold value When the threshold value is lower, the compensation voltage is used to increase the critical voltage of the driving transistor, thereby reducing the driving current. Here, the plurality of groups of pixel groups use the image acquisition device to capture pictures, and determine whether the brightness of the light-emitting diodes in each group of pixel groups in the pictures captured by the image acquisition device is lower than the first threshold value through the processing device or higher than the second threshold. In addition, the first switch circuit and the second switch circuit are switch transistors, the second switch circuit is coupled to the compensation data line, the compensation data line is used to transmit the compensation voltage output by the compensation control module, and the compensation control module is based on the judgment result of the processing device Adjust compensation voltage. Wherein, the first switch circuit is coupled to the gray-scale data line, and the gray-scale data line is used to transmit the gray-scale voltage output by the gray-scale control module, and the first switch circuit and the second switch circuit are controlled by the same scanning line to simultaneously conduct pass or end.
于本发明另一实施例中，第一开关电路与第二开关电路为开关晶体管，第一开关电路与第二开关电路耦接同一数据线，所述数据线分别耦接灰阶控制模块与补偿控制模块，且所述数据线分时地传送灰阶电压或补偿电压。其中，第一开关电路与第二开关电路分别受控于第一扫描线与第二扫描线，当第一扫描线控制第一开关电路导通时，数据线传输灰阶控制模块所输出的灰阶电压，当第二扫描线控制第二开关电路导通时，数据线传输补偿控制模块所输出的补偿电压。In another embodiment of the present invention, the first switch circuit and the second switch circuit are switch transistors, the first switch circuit and the second switch circuit are coupled to the same data line, and the data lines are respectively coupled to the gray scale control module and the compensation The control module, and the data line transmits the gray scale voltage or the compensation voltage in a time-division manner. Wherein, the first switch circuit and the second switch circuit are respectively controlled by the first scan line and the second scan line. When the first scan line controls the first switch circuit to be turned on, the data line transmits the gray scale outputted by the gray scale control module. Step voltage, when the second scan line controls the second switch circuit to be turned on, the data line transmits the compensation voltage output by the compensation control module.
本发明在于提出一种显示装置的调光方法，可判断显示画面的亮度，适应性地调制驱动晶体管的临界电压的数值，藉此调整驱动晶体管输出的驱动电流以改变发光二极管的亮度。The present invention proposes a dimming method for a display device, which can judge the brightness of a display screen and adaptively modulate the value of the threshold voltage of a driving transistor, thereby adjusting the driving current output by the driving transistor to change the brightness of a light-emitting diode.
本发明实施例提供一种显示装置的调光方法，所述显示装置具有多个像素组，每一组像素组具有发光二极管与驱动模块，驱动模块具有第一开关电路、第二开关电路以及驱动晶体管，且驱动晶体管受控于灰阶电压与补偿电压，据以调整输出给发光二极管的驱动电流。所述方法包括下列步骤：判断发光二极管的亮度是否低于第一门限值或者高于第二门限值；当发光二极管的亮度低于第一门限值时，调整补偿电压以降低驱动晶体管的临界电压，据以增加驱动电流；当发光二极管的亮度高于第二门限值时，调整补偿电压以提高驱动晶体管的临界电压，据以减少驱动电流。An embodiment of the present invention provides a dimming method of a display device, the display device has a plurality of pixel groups, each group of pixel groups has a light emitting diode and a driving module, and the driving module has a first switching circuit, a second switching circuit and a driving module. transistor, and the driving transistor is controlled by the grayscale voltage and the compensation voltage, so as to adjust the driving current output to the light emitting diode. The method includes the following steps: judging whether the brightness of the light emitting diode is lower than the first threshold value or higher than the second threshold value; when the brightness of the light emitting diode is lower than the first threshold value, adjusting the compensation voltage to reduce the driving transistor The critical voltage of the driving transistor is used to increase the driving current; when the brightness of the light-emitting diode is higher than the second threshold value, the compensation voltage is adjusted to increase the critical voltage of the driving transistor so as to reduce the driving current.
综上所述，本发明实施例提供的显示装置及其调光方法，可根据显示画面的亮度而调整输出给驱动晶体管的补偿电压，使得驱动晶体管可以依据补偿电压的大小以调制临界电压的数值，藉此调整驱动晶体管输出的驱动电流以改变发光二极管的亮度。如此一来，所述显示装置的显示画面可以减少或避免亮度不均的问题，从而改善使用者的观影质量。In summary, the display device and its dimming method provided by the embodiments of the present invention can adjust the compensation voltage output to the driving transistor according to the brightness of the display screen, so that the driving transistor can modulate the value of the critical voltage according to the magnitude of the compensation voltage , so as to adjust the driving current output by the driving transistor to change the brightness of the light emitting diode. In this way, the display screen of the display device can reduce or avoid the problem of uneven brightness, thereby improving the viewing quality of the user.
为使能更进一步了解本发明的特征及技术内容，请参阅以下有关本发明的详细说明与附图，但是此等说明与所附图式仅是用来说明本发明，而非对本发明的权利要求范围作任何的限制。In order to enable a further understanding of the features and technical content of the present invention, please refer to the following detailed description and accompanying drawings of the present invention, but these descriptions and accompanying drawings are only used to illustrate the present invention, rather than claiming the rights of the present invention Any limitations on the scope are required.
附图说明Description of drawings
图1示出了现有技术的显示装置的电路示意图。FIG. 1 shows a schematic circuit diagram of a display device in the prior art.
图2A示出了依据本发明一实施例的显示装置的局部电路示意图。FIG. 2A shows a schematic partial circuit diagram of a display device according to an embodiment of the invention.
图2B示出了依据本发明一实施例的显示装置的局部剖面示意图。FIG. 2B shows a schematic partial cross-sectional view of a display device according to an embodiment of the invention.
图3示出了依据本发明另一实施例的显示装置的局部电路示意图。FIG. 3 shows a schematic partial circuit diagram of a display device according to another embodiment of the present invention.
图4A示出了依据本发明一实施例的驱动晶体管的电路示意图。FIG. 4A shows a schematic circuit diagram of a driving transistor according to an embodiment of the invention.
图4B示出了依据本发明一实施例的驱动电流、灰阶电压与补偿电压的关系曲线图。FIG. 4B is a graph showing the relationship between the driving current, the gray scale voltage and the compensation voltage according to an embodiment of the present invention.
图4C示出了依据本发明一实施例的驱动晶体管的临界电压与补偿电压的关系曲线图。FIG. 4C is a graph showing the relationship between the threshold voltage and the compensation voltage of the driving transistor according to an embodiment of the invention.
图5示出了依据本发明一实施例的显示装置的调光方法的流程图。FIG. 5 shows a flow chart of a method for dimming a display device according to an embodiment of the present invention.
【主要元件符号说明】[Description of main component symbols]
1：显示装置10：第一开关电路1: Display device 10: First switch circuit
12：第二开关电路14：第一电容12: second switch circuit 14: first capacitor
16：第二电容18：驱动晶体管16: second capacitor 18: driving transistor
20：发光二极管S1：扫描线20: LED S1: Scanning line
D1：灰阶数据线D2：补偿数据线D1: Gray scale data line D2: Compensation data line
Vdd：高电压端Vss：低电压端Vdd: high voltage terminal Vss: low voltage terminal
302：玻璃基板304：附着层302: glass substrate 304: adhesion layer
306：栅极层308：绝缘层306: gate layer 308: insulating layer
310：通道层312：蚀刻终止层310: channel layer 312: etch stop layer
314：电极层316：保护层314: electrode layer 316: protective layer
318：平坦层320：电极层318: flat layer 320: electrode layer
322：绝缘层324：发光二极管层322: insulating layer 324: light emitting diode layer
326：电极层326: electrode layer
4：显示装置40：第一开关电路4: Display device 40: First switch circuit
42：第二开关电路44：电容42: Second switch circuit 44: Capacitor
46：电容48：驱动晶体管46: capacitor 48: drive transistor
50：发光二极管S2：扫描线50: LED S2: Scanning line
S3：扫描线D3：数据线S3: scan line D3: data line
6：驱动晶体管VG：第一栅极端6: Drive transistor VG: first gate terminal
VG’：第二栅极端VS：源极端VG': second gate terminal VS: source terminal
VD：栅极端Id：驱动电流VD: gate terminal Id: drive current
S70~S74：步骤流程9：显示装置S70~S74: Step 9: Display device
90：开关晶体管92：电容90: switching transistor 92: capacitor
94：驱动晶体管96：发光二极管94: drive transistor 96: light emitting diode
Scan：扫描线Data：数据线Scan: scan line Data: data line
具体实施方式detailed description
请一并参见图2A与图2B，图2A示出了依据本发明一实施例的显示装置的局部电路示意图，图2B示出了依据本发明一实施例的显示装置的局部剖面示意图。如图所示，显示装置1具有多个像素组，每一个像素组中至少具有发光二极管20以及驱动模块（包括元件符号10、12、14、16、18），使得驱动模块可以驱动发光二极管20。详细来说，驱动模块里的第一开关电路10分别耦接灰阶数据线D1、第一电容14以及驱动晶体管18，第二开关电路12分别耦接补偿数据线D2、第二电容16以及驱动晶体管18。驱动晶体管18为四端元件，驱动晶体管18的第一栅极端分别耦接第一开关电路10与第一电容14，驱动晶体管18的第二栅极端分别耦接第二开关电路12与第二电容16，驱动晶体管18的漏极端耦接高电压端Vdd，而驱动晶体管18的源极端经过发光二极管20耦接低电压端Vss。以下分别就显示装置1中的各部元件做更进一步地说明。Please refer to FIG. 2A and FIG. 2B together. FIG. 2A shows a schematic partial circuit diagram of a display device according to an embodiment of the present invention, and FIG. 2B shows a schematic partial cross-sectional view of a display device according to an embodiment of the present invention. As shown in the figure, the display device 1 has a plurality of pixel groups, and each pixel group has at least a light emitting diode 20 and a driving module (including element symbols 10, 12, 14, 16, 18), so that the driving module can drive the light emitting diode 20 . In detail, the first switch circuit 10 in the drive module is respectively coupled to the gray scale data line D1, the first capacitor 14 and the drive transistor 18, and the second switch circuit 12 is respectively coupled to the compensation data line D2, the second capacitor 16 and the drive transistor 18. Transistor 18. The drive transistor 18 is a four-terminal element, the first gate terminal of the drive transistor 18 is respectively coupled to the first switch circuit 10 and the first capacitor 14, and the second gate terminal of the drive transistor 18 is respectively coupled to the second switch circuit 12 and the second capacitor 16 . The drain terminal of the driving transistor 18 is coupled to the high voltage terminal Vdd, and the source terminal of the driving transistor 18 is coupled to the low voltage terminal Vss through the light emitting diode 20 . Each component in the display device 1 will be further described below.
第一开关电路10受控于扫描线S1而选择性地导通或截止，当第一开关电路10被导通时，灰阶数据线D1上承载的灰阶电压便可以顺利写入第一电容14。于实务上，扫描线S1可以连接到显示装置1中的栅极驱动器（未示出），并由栅极驱动器决定是否导通第一开关电路10。在此，虽然图2A以晶体管为例子描绘出第一开关电路10的一种可能的实施方式，但是本发明的第一开关电路10不应以晶体管为限。举例来说，第一开关电路10可以由多个晶体管所组成或者选用其他的开关元件来替代开关晶体管，于所属技术领域的普通技术人员可以视需要自由设计。The first switch circuit 10 is selectively turned on or off under the control of the scan line S1. When the first switch circuit 10 is turned on, the gray-scale voltage carried on the gray-scale data line D1 can be smoothly written into the first capacitor. 14. In practice, the scan line S1 can be connected to a gate driver (not shown) in the display device 1 , and the gate driver decides whether to turn on the first switch circuit 10 . Here, although FIG. 2A depicts a possible implementation of the first switch circuit 10 by taking a transistor as an example, the first switch circuit 10 of the present invention should not be limited to a transistor. For example, the first switch circuit 10 may be composed of multiple transistors or other switch elements may be used to replace the switch transistors, and those skilled in the art can freely design as needed.
请继续参见图2A，第二开关电路12同样受控于扫描线S1而选择性地导通或截止，当第二开关电路12被导通时，补偿数据线D2上承载的补偿电压便可以顺利写入第二电容16。在此实施例中，扫描线S1上所承载的控制信号同时控制着第一开关电路10与第二开关电路12，即栅极驱动器（未示出）同时控制是否写入灰阶电压与补偿电压，但本发明并不应以此为限。请注意，本实施例仅示出了一种可能的电路连接关系，然而只要驱动晶体管18仍可由灰阶电压与补偿电压调整驱动电流，于所属技术领域的普通技术人员也可以适当改变成其他等效的电路连接关系。Please continue to refer to FIG. 2A. The second switch circuit 12 is also selectively turned on or off under the control of the scan line S1. When the second switch circuit 12 is turned on, the compensation voltage carried on the compensation data line D2 can be smoothly Write into the second capacitor 16 . In this embodiment, the control signal carried on the scan line S1 simultaneously controls the first switch circuit 10 and the second switch circuit 12, that is, the gate driver (not shown) simultaneously controls whether to write the gray scale voltage and the compensation voltage , but the present invention should not be limited thereto. Please note that this embodiment only shows a possible circuit connection relationship, but as long as the driving transistor 18 can still adjust the driving current by the gray scale voltage and the compensation voltage, those skilled in the art can also change it to other, etc. Effective circuit connections.
为了更清楚驱动晶体管18的实体结构与元件特性，请参见图2B所示出的驱动晶体管18的剖面示意图。首先，基板302可以是玻璃或塑料材质，且基板302上会设置有附着层304以利于在基板302上设置其他功能层。驱动晶体管18的栅极层306设置在附着层304上，并且栅极层306以及附着层304上再设置绝缘层308。通道层310设置在绝缘层308上，且部分的绝缘层308与通道层310上还具有蚀刻终止层312，以避免蚀刻终止层312下方的结构于蚀刻过程中损坏。栅极层306可以是单层或多层的铜、铝、钼、钛等金属/合金所构成。附着层304、绝缘层308及蚀刻终止层312可以是单层或多层的硅的氧化物（SiOx）或氮化物（SiNx）结构。In order to understand the physical structure and device characteristics of the driving transistor 18 more clearly, please refer to the schematic cross-sectional view of the driving transistor 18 shown in FIG. 2B . Firstly, the substrate 302 can be made of glass or plastic, and an adhesion layer 304 is disposed on the substrate 302 to facilitate the formation of other functional layers on the substrate 302 . The gate layer 306 of the driving transistor 18 is disposed on the adhesion layer 304 , and an insulating layer 308 is disposed on the gate layer 306 and the adhesion layer 304 . The channel layer 310 is disposed on the insulating layer 308 , and part of the insulating layer 308 and the channel layer 310 further have an etch stop layer 312 to prevent structures under the etch stop layer 312 from being damaged during the etching process. The gate layer 306 may be composed of a single layer or multiple layers of copper, aluminum, molybdenum, titanium and other metals/alloys. The adhesion layer 304 , the insulating layer 308 and the etch stop layer 312 may be single-layer or multi-layer silicon oxide (SiOx) or nitride (SiNx) structures.
接着，电极层314设置在蚀刻终止层312上，并且接触部分的通道层310。于实务上，于图2B中接触通道层310左侧的电极层314可视为图2A中的驱动晶体管18的漏极，即左侧的电极层314会电性连接至高电压端Vdd。另外，于图2B中接触通道层310右侧的电极层314可视为图2A中的驱动晶体管18的源极。于电极层314上方设置保护层316之后，为了使接下来的工艺更顺利，于实务上还会设置一层平坦层318，以形成一个较为平整的平面。电极层314可以是单层或多层的铜、铝、钼、钛等金属/合金所构成。平坦层318材料可以是有机树脂。Next, the electrode layer 314 is disposed on the etch stop layer 312 and contacts a portion of the channel layer 310 . In practice, the electrode layer 314 on the left side of the channel layer 310 in FIG. 2B can be regarded as the drain of the driving transistor 18 in FIG. 2A , that is, the electrode layer 314 on the left side is electrically connected to the high voltage terminal Vdd. In addition, the electrode layer 314 on the right side of the channel layer 310 in FIG. 2B can be regarded as the source of the driving transistor 18 in FIG. 2A . After the protective layer 316 is disposed on the electrode layer 314 , in order to make the subsequent process smoother, a flat layer 318 is also disposed in practice to form a relatively flat plane. The electrode layer 314 may be composed of single or multiple layers of copper, aluminum, molybdenum, titanium and other metals/alloys. The flat layer 318 material may be organic resin.
一般来说，图2A中的发光二极管20为图2B中右侧电极层320、发光二极管层324以及电极层326直接层叠起来的区域（也就是面板上的发光区域），而图2B中左侧电极层320上方还具有绝缘层322（也就是面板上的非发光区域）。在此，发光二极管层324可以是有机发光二极管材料所制成，而电极层320以及电极层326分别是发光二极管层324的阳极与阴极。换句话说，发光二极管20实际上可以为一种有机发光二极管（OLED），且电极层320以及电极层326可以由透明导电材料（例如ITO）或者其他适当的材料制成。绝缘层322材料可以是有机树脂。Generally speaking, the light emitting diode 20 in FIG. 2A is the area where the electrode layer 320, the light emitting diode layer 324 and the electrode layer 326 on the right side of FIG. There is also an insulating layer 322 above the electrode layer 320 (that is, the non-light-emitting area on the panel). Here, the light emitting diode layer 324 may be made of organic light emitting diode material, and the electrode layer 320 and the electrode layer 326 are respectively an anode and a cathode of the light emitting diode layer 324 . In other words, the light emitting diode 20 can actually be an organic light emitting diode (OLED), and the electrode layer 320 and the electrode layer 326 can be made of a transparent conductive material (such as ITO) or other suitable materials. The material of the insulating layer 322 may be organic resin.
请注意，图2B中分别示出有两个区块的电极层320，于右侧的电极层320接触通道层310右侧的电极层314（即驱动晶体管18的源极），而左侧的电极层320位于通道层310之上。从半导体的原理可知，当左侧的电极层320提供正电压时，电子较易聚集而形成电流信道，使得驱动晶体管18的临界电压将会降低，而驱动晶体管18输出的驱动电流会随之提高。相反的，当左侧的电极层320提供负电压时，电子不较易聚集成电流通道，使得驱动晶体管18的临界电压将会提高，而驱动晶体管18输出的驱动电流会随之降低。Please note that there are two electrode layers 320 respectively shown in FIG. The electrode layer 320 is located on the channel layer 310 . It can be seen from the principle of semiconductors that when the electrode layer 320 on the left provides a positive voltage, electrons are more likely to gather to form a current channel, so that the critical voltage of the driving transistor 18 will decrease, and the driving current output by the driving transistor 18 will increase accordingly. . On the contrary, when the left electrode layer 320 provides a negative voltage, electrons are less likely to gather into a current channel, so that the threshold voltage of the driving transistor 18 will increase, and the driving current output by the driving transistor 18 will decrease accordingly.
据此，通过本实施例中的驱动晶体管18的设计，使得显示装置1中每个像素组不需大幅增加晶体管的数量，也可以简易地通过储存于第二电容16中的补偿电压调整驱动晶体管18的临界电压，从而调整了驱动晶体管18输出给的发光二极管20的驱动电流。Accordingly, through the design of the driving transistor 18 in this embodiment, each pixel group in the display device 1 does not need to greatly increase the number of transistors, and the driving transistor can also be easily adjusted through the compensation voltage stored in the second capacitor 16. 18 , thereby adjusting the driving current outputted by the driving transistor 18 to the LED 20 .
为了举出显示装置1其他的等效电路连接关系，本发明还披露了另一种可能的实施方式。请参见图3，图3示出了依据本发明另一实施例的显示装置的局部电路示意图。如图3所示，显示装置4同样可具有多个像素组，每一个像素组中至少具有发光二极管50以及驱动模块（包括元件符号40、42、44、46、48），使得驱动模块可以驱动发光二极管50。与前一实施例相同的是，电容44、电容46、驱动晶体管48以及发光二极管50的电路连接关系与操作方式，本实施例在此不予赘述。与前一实施例不同的是，第一开关电路40与第二开关电路42连接到同一条数据线D3，并且分别受控于不同的扫描线S2、S3。In order to enumerate other equivalent circuit connection relationships of the display device 1 , the present invention also discloses another possible implementation manner. Please refer to FIG. 3 , which shows a partial circuit diagram of a display device according to another embodiment of the present invention. As shown in FIG. 3 , the display device 4 can also have a plurality of pixel groups, and each pixel group has at least a light emitting diode 50 and a driving module (including element symbols 40, 42, 44, 46, 48), so that the driving module can drive LED 50. The same as the previous embodiment, the circuit connection relationship and operation mode of the capacitor 44 , the capacitor 46 , the driving transistor 48 and the light emitting diode 50 will not be repeated in this embodiment. Different from the previous embodiment, the first switch circuit 40 and the second switch circuit 42 are connected to the same data line D3 and controlled by different scan lines S2 and S3 respectively.
详细来说，数据线D3会分时地传送灰阶电压与补偿电压，而传送灰阶电压或补偿电压的时段应恰好对应扫描线S2、S3控制第一开关电路40或第二开关电路42导通的时段。举例来说，第一开关电路40受控于扫描线S2而选择性地导通或截止，当第一开关电路40被导通时，数据线D3应恰好传送着灰阶电压，使得灰阶电压便可以顺利写入电容44。另一方面，当灰阶电压写入电容44后且第二开关电路42被导通时，数据线D3可以转而传送补偿电压，使得补偿电压便可以顺利写入电容46。在此，本实施例并不限制传送灰阶电压与补偿电压的顺序或者传送时间长短，于所属技术领域的普通技术人员可以视需要自由设计。In detail, the data line D3 transmits the grayscale voltage and the compensation voltage in a time-division manner, and the time period for transmitting the grayscale voltage or the compensation voltage should be exactly corresponding to the scanning lines S2 and S3 to control the first switch circuit 40 or the second switch circuit 42 to conduct. pass time. For example, the first switch circuit 40 is selectively turned on or off under the control of the scan line S2. When the first switch circuit 40 is turned on, the data line D3 should just transmit the gray-scale voltage, so that the gray-scale voltage Then the capacitor 44 can be written into smoothly. On the other hand, when the grayscale voltage is written into the capacitor 44 and the second switch circuit 42 is turned on, the data line D3 can transfer the compensation voltage instead, so that the compensation voltage can be written into the capacitor 46 smoothly. Here, the present embodiment does not limit the order of transmitting the grayscale voltage and the compensation voltage or the length of transmission time, and those skilled in the art can freely design as needed.
当然，虽然图3同样以晶体管为例子描绘出第一开关电路40与第二开关电路42的一种可能的实施方式，但是本发明的第一开关电路40与第二开关电路42同样不应以晶体管为限。Of course, although FIG. 3 also uses transistors as an example to depict a possible implementation of the first switch circuit 40 and the second switch circuit 42, the first switch circuit 40 and the second switch circuit 42 of the present invention should not be used in the same way. Transistors are limited.
以图3实际的例子来说，为了判断显示装置4是否产生画面亮度分布不均匀（mura效应）的问题，于进行品管或是检测时，还可以先利用一组图像获取装置（未示出）拍摄显示装置4于发光时的画面，所述图像获取装置例如可以选用CCD摄影机或其他适当的摄影器材。接着，还可经由处理装置（未示出）观察或判断于图像获取装置拍摄到的画面中，每一组像素组中的发光二极管50的亮度是否符合标准，例如亮度是否低于第一门限值（即太暗）或是否高于第二门限值（即太亮）。当然，第一门限值与第二门限值可预先由使用者自行选定，第一门限值与第二门限值可以相等，或是分别为一个范围区间内的下限与上限，本实施例在此不加以限制。Taking the actual example in FIG. 3 as an example, in order to determine whether the display device 4 has a problem of uneven brightness distribution (mura effect), a group of image acquisition devices (not shown) can also be used when performing quality control or inspection. out) to take pictures of the display device 4 when it emits light, and the image acquisition device can be a CCD camera or other appropriate photographic equipment, for example. Next, it is also possible to observe or judge through the processing device (not shown) whether the brightness of the light-emitting diodes 50 in each group of pixel groups in the picture captured by the image acquisition device meets the standard, for example, whether the brightness is lower than the first threshold value (i.e. too dark) or above the second threshold (i.e. too bright). Of course, the first threshold value and the second threshold value can be pre-selected by the user. The first threshold value and the second threshold value can be equal, or they can be the lower limit and upper limit of a range. The examples are not limited here.
于实务上，第一门限值与第二门限值可以预先被设置在一个查找表中，所述查找表可以记录着亮度对应补偿电压的关系。举例来说，当处理装置判断某一个像素组中的发光二极管50太暗或太亮时，可以通过查找表找出适于补偿驱动晶体管48的补偿电压，并经由第二开关电路42储存在电容46中。据此，驱动晶体管48的临界电压可以被动态地调整，所述像素组的亮度于补偿后均在一个可接受的范围内。In practice, the first threshold value and the second threshold value can be preset in a lookup table, and the lookup table can record the relationship between brightness and compensation voltage. For example, when the processing device determines that the light emitting diode 50 in a certain pixel group is too dark or too bright, it can find out the compensation voltage suitable for compensating the driving transistor 48 through a lookup table, and store it in the capacitor 46 via the second switch circuit 42 middle. Accordingly, the threshold voltage of the driving transistor 48 can be dynamically adjusted, and the brightness of the pixel group is within an acceptable range after compensation.
从实际测量的数据来看，请一并参见图4A、图4B以及图4C，图4A示出了依据本发明一实施例的驱动晶体管的电路示意图，图4B示出了依据本发明一实施例的驱动电流、灰阶电压与补偿电压的关系曲线图，图4C示出了依据本发明一实施例的驱动晶体管的临界电压与补偿电压的关系曲线图。驱动晶体管6具有第一栅极端VG、第二栅极端VG’、源极端VS与栅极端VD，第一栅极端VG用以耦接前一实施例的第一开关电路与储存灰阶电压的电容，而第二栅极端VG’用以耦接前一实施例的第二开关电路与储存补偿电压的电容。From the actual measured data, please refer to FIG. 4A, FIG. 4B and FIG. 4C together. FIG. 4A shows a schematic circuit diagram of a drive transistor according to an embodiment of the present invention, and FIG. 4B shows 4C is a graph showing the relationship between the threshold voltage and the compensation voltage of the driving transistor according to an embodiment of the present invention. The driving transistor 6 has a first gate terminal VG, a second gate terminal VG′, a source terminal VS, and a gate terminal VD. The first gate terminal VG is used for coupling the first switch circuit of the previous embodiment and the capacitor for storing the gray scale voltage. , and the second gate terminal VG' is used to couple the second switch circuit and the capacitor for storing the compensation voltage in the previous embodiment.
由图4B的实际数据可知，在灰阶电压不变的情况下（例如VG为8V时），第二栅极端VG’收到的补偿电压越高，则驱动电流Id明显会随着提高。此外，由图4C的实际数据可知，第二栅极端VG’收到的补偿电压愈高，则驱动晶体管6的临界电压Vth会越低，从晶体管的基础电流公式可知，临界电压Vth越低则驱动电流Id必然会越高，而临界电压Vth越高则驱动电流Id会随着越低。藉此，本实施例提供的驱动晶体管6可以轻易地用不同的补偿电压调整输出给发光二极管的驱动电流。It can be seen from the actual data in FIG. 4B that, under the condition that the gray scale voltage remains unchanged (for example, when VG is 8V), the higher the compensation voltage received by the second gate terminal VG', the higher the driving current Id will obviously increase. In addition, it can be seen from the actual data in FIG. 4C that the higher the compensation voltage received by the second gate terminal VG', the lower the critical voltage Vth of the driving transistor 6 will be. From the basic current formula of the transistor, the lower the critical voltage Vth is, the lower the threshold voltage Vth will be. The driving current Id must be higher, and the higher the threshold voltage Vth is, the lower the driving current Id will be. Thereby, the driving transistor 6 provided in this embodiment can easily adjust the driving current output to the LED with different compensation voltages.
为了使所属技术领域的普通技术人员能了解本发明的精神，以下将本发明的显示装置搭配显示装置的调光方法做更清楚地说明。In order to make those of ordinary skill in the art understand the spirit of the present invention, the display device of the present invention and the dimming method of the display device are described more clearly below.
请一并参见图3与图5，图5示出了依据本发明一实施例的显示装置的调光方法的流程图。如图所示，于步骤S70中，本实施例会先利用一组图像获取装置（未示出）拍摄显示装置4于发光时的画面，并由处理装置（未示出）判断于图像获取装置拍摄到的画面中，每一组像素组中的发光二极管50的亮度是否低于第一门限值（即太暗）或是否高于第二门限值（即太亮）。Please refer to FIG. 3 and FIG. 5 together. FIG. 5 shows a flowchart of a method for dimming a display device according to an embodiment of the present invention. As shown in the figure, in step S70, this embodiment first uses a group of image acquisition devices (not shown) to capture the picture of the display device 4 when it emits light, and the processing device (not shown) determines whether the image acquisition device In the captured picture, whether the brightness of the light emitting diodes 50 in each pixel group is lower than the first threshold (that is, too dark) or whether it is higher than the second threshold (that is, too bright).
于步骤S72中，当处理装置判断某一个像素组中的发光二极管50太暗时，会将输出给电容46的补偿电压提高，据以降低驱动晶体管48的临界电压，使得流经发光二极管50的驱动电流提高，从而增加发光二极管50的亮度。于步骤S74中，当处理装置判断某一个像素组中的发光二极管50太亮时，会将输出给电容46的补偿电压降低，据以提高驱动晶体管48的临界电压，使得流经发光二极管50的驱动电流降低，从而减少发光二极管50的亮度。In step S72, when the processing device judges that the light emitting diode 50 in a certain pixel group is too dark, it will increase the compensation voltage output to the capacitor 46, so as to reduce the threshold voltage of the driving transistor 48, so that the light flowing through the light emitting diode 50 The driving current increases, thereby increasing the brightness of the LED 50 . In step S74, when the processing device determines that the light emitting diode 50 in a certain pixel group is too bright, it will reduce the compensation voltage output to the capacitor 46, so as to increase the threshold voltage of the driving transistor 48, so that the driving light flowing through the light emitting diode 50 The current is reduced, thereby reducing the brightness of the LED 50 .
综上所述，本发明实施例提供的显示装置及其调光方法，可根据显示画面的亮度而调整输出给驱动晶体管的补偿电压，使得驱动晶体管可以依据补偿电压的大小而调制临界电压的数值，藉此调整驱动晶体管输出的驱动电流以改变发光二极管的亮度。如此一来，所述显示装置的显示画面可以减少或避免亮度不均的问题，从而改善使用者的观影质量。In summary, the display device and its dimming method provided by the embodiments of the present invention can adjust the compensation voltage output to the driving transistor according to the brightness of the display screen, so that the driving transistor can modulate the value of the threshold voltage according to the magnitude of the compensation voltage , so as to adjust the driving current output by the driving transistor to change the brightness of the light emitting diode. In this way, the display screen of the display device can reduce or avoid the problem of uneven brightness, thereby improving the viewing quality of the user.
通过以上优选具体实施例的详述，希望能更加清楚描述本发明的特征与精神，而并非以上述所披露的优选具体实施例来对本发明的范畴加以限制。相反地，其目的是希望能涵盖各种改变及具相等性的安排于本发明所欲申请的专利范围的范畴内。Through the above detailed description of the preferred specific embodiments, it is hoped that the characteristics and spirit of the present invention can be described more clearly, rather than the scope of the present invention is limited by the preferred specific embodiments disclosed above. On the contrary, the intention is to cover various changes and equivalent arrangements within the scope of the claimed patent scope of the present invention.
| Application Number | Priority Date | Filing Date | Title |
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| CN201210345600.2ACN103680391B (en) | 2012-09-17 | 2012-09-17 | Display device and dimming method thereof |
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| CN201210345600.2ACN103680391B (en) | 2012-09-17 | 2012-09-17 | Display device and dimming method thereof |
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| CN103680391A CN103680391A (en) | 2014-03-26 |
| CN103680391Btrue CN103680391B (en) | 2016-01-13 |
| Application Number | Title | Priority Date | Filing Date |
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| CN201210345600.2AActiveCN103680391B (en) | 2012-09-17 | 2012-09-17 | Display device and dimming method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN106097963B (en)* | 2016-08-19 | 2018-07-06 | 京东方科技集团股份有限公司 | Circuit structure, display equipment and driving method |
| JP6910444B2 (en) | 2016-12-27 | 2021-07-28 | シェンジェン ロイオル テクノロジーズ カンパニー リミテッドＳｈｅｎｚｈｅｎ Ｒｏｙｏｌｅ Ｔｅｃｈｎｏｌｏｇｉｅｓ Ｃｏ．， Ｌｔｄ． | Pixel circuit drive method, pixel circuit group and organic light emission display device |
| CN107680536B (en)* | 2017-10-26 | 2019-07-09 | 京东方科技集团股份有限公司 | Pixel circuit, driving method thereof, organic light-emitting display panel, and display device |
| CN109545144A (en)* | 2018-11-27 | 2019-03-29 | 武汉华星光电半导体显示技术有限公司 | A kind of luminance regulating method and device of display panel |
| US10624190B1 (en)* | 2019-01-21 | 2020-04-14 | Mikro Mesa Technology Co., Ltd. | Micro light-emitting diode driving circuit and method for driving the same |
| CN117789624A (en)* | 2022-09-29 | 2024-03-29 | 荣耀终端有限公司 | Voltage adjustment method, terminal equipment, chip and storage medium |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100452114B1 (en)* | 2002-04-15 | 2004-10-12 | 한국과학기술원 | Pixel circuit and Organic Light Eitting Dode display using the same |
| CN1871631A (en)* | 2003-09-23 | 2006-11-29 | 伊格尼斯创新有限公司 | Pixel driver circuit |
| CN102646388A (en)* | 2011-06-02 | 2012-08-22 | 京东方科技集团股份有限公司 | A kind of driving device, OLED panel and OLED panel driving method |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100986896B1 (en)* | 2008-12-05 | 2010-10-08 | 삼성모바일디스플레이주식회사 | Organic light emitting display device and driving method thereof |
| TWI410929B (en)* | 2010-04-16 | 2013-10-01 | Au Optronics Corp | Pixel circuit relating to organic light emitting diode and display using the same and driving method thereof |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100452114B1 (en)* | 2002-04-15 | 2004-10-12 | 한국과학기술원 | Pixel circuit and Organic Light Eitting Dode display using the same |
| CN1871631A (en)* | 2003-09-23 | 2006-11-29 | 伊格尼斯创新有限公司 | Pixel driver circuit |
| CN102646388A (en)* | 2011-06-02 | 2012-08-22 | 京东方科技集团股份有限公司 | A kind of driving device, OLED panel and OLED panel driving method |
| Publication number | Publication date |
|---|---|
| CN103680391A (en) | 2014-03-26 |
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