CN111028785A - 基于有机薄膜晶体管的amoled电压型像素补偿驱动电路 - Google Patents
基于有机薄膜晶体管的amoled电压型像素补偿驱动电路 Download PDFInfo
- Publication number
- CN111028785A CN111028785A CN201911358796.7A CN201911358796A CN111028785A CN 111028785 A CN111028785 A CN 111028785A CN 201911358796 A CN201911358796 A CN 201911358796A CN 111028785 A CN111028785 A CN 111028785A
- Authority
- CN
- China
- Prior art keywords
- thin film
- film transistor
- organic thin
- voltage
- oled
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
- G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
- G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
- G09G3/3208—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
- G09G3/3225—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix
- G09G3/3258—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix with pixel circuitry controlling the voltage across the light-emitting element
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
- G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
- G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
- G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
- G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
- G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
- G09G3/3208—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
- G09G3/3266—Details of drivers for scan electrodes
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Control Of El Displays (AREA)
- Control Of Indicators Other Than Cathode Ray Tubes (AREA)
- Electroluminescent Light Sources (AREA)
Abstract
本发明公开了一种基于有机薄膜晶体管的AMOLED电压型像素补偿驱动电路,其用5个有机薄膜晶体管驱动OLED,通过补偿有机薄膜晶体管的阈值电压来提高图像的质量。基于有机薄膜晶体管的特殊性质,采用全新的电路设计结构,在对阈值电压进行补偿的基础上还有效的防止了有机薄膜晶体管漏电对像素电路电流均匀性造成的影响。
Description
技术领域
本发明属于电子电路技术及显示技术等领域,具体涉及一种基于有机薄膜晶体管的AMOLED电压型像素补偿驱动电路。
背景技术
近年来,以有源矩阵有机发光二极管(AMOLED)为代表的新型平板显示产业发展迅速。随着智能手机、大型3D显示器、透明显示器和灵活显示器的分辨率不断提高,对显示技术的要求也越来越高。目前AMOLED面板中常用的薄膜晶体管分为金属氧化物TFT和低温多晶硅TFT。由于Si材料的机械性能、刚性等原因,没有一种能够实现柔性显示,所以要制备出一种特殊的晶体管来代替传统的的无机晶体管,来实现柔性显示,有机薄膜晶体管(OTFT)因其制造简单、成本低、大面积制造和良好的柔性而备受关注,这使得它有可能应用于平板显示器、电子纸、射频识别标签和传感器。但是柔性AMOLED有一个缺点,有机薄膜晶体管(OTFT)的电学特性参数在实际使用的过程中会发生变化由于发热等原因,电学特性参数变化会造成屏幕显示亮度不一致这样的问题。目前现有的像素电路无法解决这个问题,因此为了实现柔性AMOLED显示屏幕亮度均匀的目的而研究设计具有阈值电压补偿的像素驱动电路的设计。
由于OTFT性质比较特殊,由OTFT集成的像素电路,由于发光,温度变化等原因会造成OTFT阈值电压的变化,从而引起OLED电流的变化,导致屏幕发光不均匀等问题。所以对驱动OTFT的阈值电压进行补偿是必要的。当前,已有很多方法用于补偿阈值电压,如电流编程和电压编程两种方法,但是由于电流编程的方法需要更多的响应时间,故发明采用电压编程的方法,采用电压编程的方法实现快速补偿OTFT的VTH的变化。
发明内容
本发明的目的在于克服现有技术的不足,提供一种基于有机薄膜晶体管的AMOLED电压型像素补偿驱动电路,其用5个OTFT驱动OLED,通过补偿OTFT的阈值电压来提高图像的质量。基于OTFT的特殊性质,采用全新的电路设计结构,在对阈值电压进行补偿的基础上还有效的防止了OTFT漏电对像素电路电流均匀性造成的影响。
本发明还提供一种驱动OLED实现阈值电压补偿电路的驱动方法,该方法可以准确的对电路的阈值电压进行补偿。
本发明是通过以下技术方案实现的:
一种基于有机薄膜晶体管的AMOLED电压型像素补偿驱动电路,包括第一有机薄膜晶体管、第二有机薄膜晶体管、第三有机薄膜晶体管、第四有机薄膜晶体管、第五有机薄膜晶体管、电容Cs以及有机发光二极管OLED;
第一有机薄膜晶体管的源极与电源电压VDD相连,栅极连接第一扫描控制线SCAN1,漏极与点A相连接;第二有机薄膜晶体管的栅极与第二扫描控制线SCAN2连接,源极与数据信号线VDATA相连,漏极连接点B;第三有机薄膜晶体管的栅极与第三扫描控制线SCAN3连接,漏极与第五薄膜晶体管的栅极相连,源极连接点B;第四有机薄膜晶体管的栅极与第二扫描控制线SCAN2相连,源极与第五薄膜晶体管的栅极相连,漏极与有机发光二极管OLED的阳极相连;第五有机薄膜晶体管为电路的驱动晶体管,其栅极与第三薄膜晶体管的漏极相连,源极与点A相连,漏极与有机发光二极管OLED的阳极相连。
所述的基于有机薄膜晶体管的AMOLED电压型像素补偿驱动电路的驱动方法,其包括初始阶段、阈值电压补偿阶段和发光阶段,具体如下:
在初始阶段:第一扫描控制线、第二扫描控制线、第三扫描控制线均设置成低电平,所有有机薄膜晶体管都开启,此时,A点电压VA等于电源电压VDD,B点电压VB等于数据信号线电压VDATA;
在阈值电压补偿阶段:第一扫描控制线为高电平,第二扫描控制线为低电平,第三扫描控制线为高电平,此时,第一薄膜晶体管关闭,电容Cs开始放电,一直放到VA=VOLED+|VTH|为止,此时第五有机薄膜晶体管关闭。其中,VA为A点电压,VTH为第五有机薄膜晶体管的阈值电压,当没有电流流过OLED时,VOLED的大小为OLED的阈值电压;
在发光阶段:第一扫描控制线和第三扫描控制线为低电平,第二扫描控制线为高电平,此时,A点电压VA等于电源电压VDD,根据电容的自举特性,此时B点电压VB等于VDATA+VDD-VOLED-|VTH|;根据OLED电流公式IOLED=k(VSG-|VTH|)2=k(VDD–(VDATA+VDD-VOLED-|VTH|)-|VTH|)2=k(VOLED-VDATA)2,式中,VSG为驱动晶体管的源栅电压,VSG=VA-VB,k=(1/2)μCox(W/L)2(其中,u为驱动晶体管的载流子迁移率,Cox为单位面积电容,W/L是驱动晶体管的宽长比);根据电流公式可以看出变量VTH被抵消了,无论阈值电压如何变化对电流也不会造成影响。可以看出本电路可以准确的对驱动晶体管的阈值电压进行补偿,从而提高AMOLED的显示品质。
本发明的优点和有益效果为:
1.本电路采用有机薄膜晶体管驱动OLED,可以实现柔性显示这样的一个功能。
2.该像素驱动电路是基于有机薄膜晶体管(OTFT)的性质设计的,利用设计测试模块实测驱动晶体管的阈值电压,可以更加准确的补偿驱动晶体管老化而引起的阈值电压漂移的问题,有效的提高显示效果。
3.该像素驱动电路还具有快速检验驱动晶体管补偿效果的功能,可以检测该像素电路是否具有阈值电压补偿效果。
附图说明
图1是本发明的电路图。
图2是本发明的电路控制时序图。
对于本领域普通技术人员来讲,在不付出创造性劳动的前提下,可以根据以上附图获得其他的相关附图。
具体实施方式
为了使本技术领域的人员更好地理解本发明方案,下面结合具体实施例进一步说明本发明的技术方案。
实施例一
参见附图1,一种基于有机薄膜晶体管的AMOLED电压型像素补偿驱动电路,包括第一有机薄膜晶体管OTFT1、第二有机薄膜晶体管OTFT2、第三有机薄膜晶体管OTFT3、第四有机薄膜晶体管OTFT4、第五有机薄膜晶体管OTFT5、电容Cs以及有机发光二极管OLED。第一有机薄膜晶体管的源极与电源电压VDD相连,栅极连接第一扫描控制线SCAN1,漏极与点A相连接;第二有机薄膜晶体管的栅极与第二扫描控制线SCAN2连接,源极与数据信号线VDATA相连,漏极连接点B;第三有机薄膜晶体管的栅极与第三扫描控制线SCAN3连接,漏极与第五薄膜晶体管的栅极相连,源极连接点B;第四有机薄膜晶体管的栅极与第二扫描控制线SCAN2相连,源极与第五薄膜晶体管的栅极相连,漏极与有机发光二极管OLED的阳极相连;第五有机薄膜晶体管为电路的驱动晶体管,其栅极与第三薄膜晶体管的漏极相连,源极与点A相连,漏极与有机发光二极管OLED的阳极相连。
实施例二
下面结合图2详细说明本发明的工作原理,上述像素补偿驱动电路可分为三个阶段,初始阶段、阈值电压补偿阶段和发光阶段,每个阶段的操作方法如下:
在初始阶段,第一扫描控制线、第二扫描控制线、第三扫描控制线均设置成低电平,所有有机薄膜晶体管都开启,此时,A点电压VA等于电源电压VDD,B点电压VB等于数据信号线电压VDATA。
在阈值电压补偿阶段,第一扫描控制线为高电平,第二扫描控制线为低电平,第三扫描控制线为高电平,此时,第一薄膜晶体管关闭,电容Cs开始放电,一直放到VA=VOLED+|VTH|为止,此时第五有机薄膜晶体管(即驱动晶体管)关闭。其中,VA为A点电压,VTH为第五有机薄膜晶体管(即驱动晶体管)的阈值电压,当没有电流流过OLED时,VOLED的大小为OLED的阈值电压。
在发光阶段:第一扫描控制线和第三扫描控制线为低电平,第二扫描控制线为高电平,此时,A点电压VA等于电源电压VDD,根据电容的自举特性,此时B点电压VB等于VDATA+VDD-VOLED-|VTH|;根据OLED电流公式IOLED=k(VSG-|VTH|)2=k(VDD–(VDATA+VDD-VOLED-|VTH|)-|VTH|)2=k(VOLED-VDATA)2,式中,VSG为驱动晶体管的源栅电压,VSG=VA-VB,k=(1/2)μCox(W/L)2(其中,u为驱动晶体管的载流子迁移率,Cox为单位面积电容,W/L是驱动晶体管的宽长比);根据电流公式可以看出变量VTH被抵消了,无论阈值电压如何变化对电流也不会造成影响。可以看出本电路可以准确的对驱动晶体管的阈值电压进行补偿,从而提高AMOLED的显示品质。
为了易于说明,实施例中使用了诸如“第一”和“第二”等之类的关系术语仅仅用来将一个与另一个具有相同名称的部件区分开来,而不一定要求或者暗示这些部件之间存在任何这种实际的关系或者顺序。
以上对本发明做了示例性的描述,应该说明的是,在不脱离本发明的核心的情况下,任何简单的变形、修改或者其他本领域技术人员能够不花费创造性劳动的等同替换均落入本发明的保护范围。
Claims (2)
1.一种基于有机薄膜晶体管的AMOLED电压型像素补偿驱动电路,其特征在于:包括第一有机薄膜晶体管、第二有机薄膜晶体管、第三有机薄膜晶体管、第四有机薄膜晶体管、第五有机薄膜晶体管、电容Cs以及有机发光二极管OLED;
第一有机薄膜晶体管的源极与电源电压VDD相连,栅极连接第一扫描控制线SCAN1,漏极与点A相连接;第二有机薄膜晶体管的栅极与第二扫描控制线SCAN2连接,源极与数据信号线VDATA相连,漏极连接点B;第三有机薄膜晶体管的栅极与第三扫描控制线SCAN3连接,漏极与第五薄膜晶体管的栅极相连,源极连接点B;第四有机薄膜晶体管的栅极与第二扫描控制线SCAN2相连,源极与第五薄膜晶体管的栅极相连,漏极与有机发光二极管OLED的阳极相连;第五有机薄膜晶体管为电路的驱动晶体管,其栅极与第三薄膜晶体管的漏极相连,源极与点A相连,漏极与有机发光二极管OLED的阳极相连。
2.根据权利要求1所述的基于有机薄膜晶体管的AMOLED电压型像素补偿驱动电路的驱动方法,其包括初始阶段、阈值电压补偿阶段和发光阶段,其特征在于:
在初始阶段:第一扫描控制线、第二扫描控制线、第三扫描控制线均设置成低电平,所有有机薄膜晶体管都开启,此时,A点电压VA等于电源电压VDD,B点电压VB等于数据信号线电压VDATA;
在阈值电压补偿阶段:第一扫描控制线为高电平,第二扫描控制线为低电平,第三扫描控制线为高电平,此时,第一薄膜晶体管关闭,电容Cs开始放电,一直放到VA=VOLED+|VTH|为止,此时第五有机薄膜晶体管关闭。其中,VA为A点电压,VTH为第五有机薄膜晶体管的阈值电压,当没有电流流过OLED时,VOLED的大小为OLED的阈值电压;
在发光阶段:第一扫描控制线和第三扫描控制线为低电平,第二扫描控制线为高电平,此时,A点电压VA等于电源电压VDD,根据电容的自举特性,此时B点电压VB等于VDATA+VDD-VOLED-|VTH|;根据OLED电流公式IOLED=k(VSG-|VTH|)2=k(VDD–(VDATA+VDD-VOLED-|VTH|)-|VTH|)2=k(VOLED-VDATA)2,由于变量VTH被抵消了,无论阈值电压如何变化对电流也不会造成影响。
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201911358796.7A CN111028785A (zh) | 2019-12-25 | 2019-12-25 | 基于有机薄膜晶体管的amoled电压型像素补偿驱动电路 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201911358796.7A CN111028785A (zh) | 2019-12-25 | 2019-12-25 | 基于有机薄膜晶体管的amoled电压型像素补偿驱动电路 |
Publications (1)
Publication Number | Publication Date |
---|---|
CN111028785A true CN111028785A (zh) | 2020-04-17 |
Family
ID=70213307
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201911358796.7A Pending CN111028785A (zh) | 2019-12-25 | 2019-12-25 | 基于有机薄膜晶体管的amoled电压型像素补偿驱动电路 |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN111028785A (zh) |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102595059A (zh) * | 2012-02-27 | 2012-07-18 | 天津大学 | 一种像素结构及其多次曝光方法 |
CN103700342A (zh) * | 2013-12-12 | 2014-04-02 | 京东方科技集团股份有限公司 | Oled像素电路及驱动方法、显示装置 |
CN207425323U (zh) * | 2017-11-29 | 2018-05-29 | 京东方科技集团股份有限公司 | 一种oled像素电路、显示装置 |
CN109256092A (zh) * | 2018-10-18 | 2019-01-22 | 天津大学 | 基于otft的实现阈值电压补偿的像素驱动电路及驱动方法 |
-
2019
- 2019-12-25 CN CN201911358796.7A patent/CN111028785A/zh active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102595059A (zh) * | 2012-02-27 | 2012-07-18 | 天津大学 | 一种像素结构及其多次曝光方法 |
CN103700342A (zh) * | 2013-12-12 | 2014-04-02 | 京东方科技集团股份有限公司 | Oled像素电路及驱动方法、显示装置 |
CN207425323U (zh) * | 2017-11-29 | 2018-05-29 | 京东方科技集团股份有限公司 | 一种oled像素电路、显示装置 |
CN109256092A (zh) * | 2018-10-18 | 2019-01-22 | 天津大学 | 基于otft的实现阈值电压补偿的像素驱动电路及驱动方法 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN106652911B (zh) | Oled像素驱动电路及oled显示装置 | |
CN107342052B (zh) | 用于oled显示设备的像素驱动电路 | |
US10380941B2 (en) | OLED pixel circuit and display device thereof | |
CN105913801B (zh) | 一种有机发光显示面板及其驱动方法 | |
US10593260B1 (en) | Pixel driving circuit for OLED display device and OLED display device | |
CN103077680B (zh) | 一种oled像素驱动电路 | |
US10354592B2 (en) | AMOLED pixel driver circuit | |
CN108847186B (zh) | 像素电路及其驱动方法、显示面板及显示装置 | |
WO2016187990A1 (zh) | 像素电路以及像素电路的驱动方法 | |
CN109785797B (zh) | 一种amoled像素电路 | |
CN106531041B (zh) | Oled驱动薄膜晶体管的k值侦测方法 | |
CN108492768B (zh) | 一种面板裂纹检测结构及检测方法 | |
CN109256092B (zh) | 基于otft的实现阈值电压补偿的像素驱动电路及驱动方法 | |
CN110264957B (zh) | 一种像素电路的补偿方法、装置、显示设备 | |
CN105427805A (zh) | 像素驱动电路、方法、显示面板和显示装置 | |
CN110875009B (zh) | 显示面板及其驱动方法 | |
CN108335671B (zh) | Amoled像素驱动电路及驱动方法 | |
CN111048044B (zh) | 电压编程型amoled像素驱动电路及其驱动方法 | |
CN102682704A (zh) | 有源有机电致发光显示器的像素驱动电路及其驱动方法 | |
CN104167173A (zh) | 主动式有机发光二极管显示器的像素电路 | |
US11620950B2 (en) | Pixel driving circuit, driving method, display panel and display device | |
CN110189707A (zh) | 一种像素驱动电路及其驱动方法、显示装置 | |
US20210074210A1 (en) | Pixel driving circuit, method for driving the same, array substrate and display device | |
CN105139805A (zh) | 一种像素驱动电路及其驱动方法、显示装置 | |
CN108777132A (zh) | 像素电路及其驱动方法、显示面板及显示装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
RJ01 | Rejection of invention patent application after publication | ||
RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200417 |