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CN105989794B - Oled显示装置 - Google Patents

Oled显示装置 Download PDF

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CN105989794B
CN105989794B CN201510047411.0A CN201510047411A CN105989794B CN 105989794 B CN105989794 B CN 105989794B CN 201510047411 A CN201510047411 A CN 201510047411A CN 105989794 B CN105989794 B CN 105989794B
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pixel unit
oled display
light emitting
state
line
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CN105989794A (zh
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周兴雨
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EverDisplay Optronics Shanghai Co Ltd
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EverDisplay Optronics Shanghai Co Ltd
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Priority to KR1020160010378A priority patent/KR20160093556A/ko
Priority to US15/017,345 priority patent/US9947272B2/en
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    • 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]
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    • G09G3/3233—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 current through the light-emitting element
    • G09G3/3241—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 current through the light-emitting element the current through the light-emitting element being set using a data current provided by the data driver, e.g. by using a two-transistor current mirror
    • G09G3/325—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 current through the light-emitting element the current through the light-emitting element being set using a data current provided by the data driver, e.g. by using a two-transistor current mirror the data current flowing through the driving transistor during a setting phase, e.g. by using a switch for connecting the driving transistor to the data driver
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/15—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components having potential barriers, specially adapted for light emission
    • H01L27/153—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components having potential barriers, specially adapted for light emission in a repetitive configuration, e.g. LED bars
    • H01L27/156—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components having potential barriers, specially adapted for light emission in a repetitive configuration, e.g. LED bars two-dimensional arrays
    • G—PHYSICS
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    • G09G2300/08—Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
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    • G09G2300/0861—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
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    • 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]
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    • 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
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  • Condensed Matter Physics & Semiconductors (AREA)
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Abstract

本发明公开了一种OLED显示装置，包括：呈阵列分布的像素单元，每行所述像素单元连接有一条用于向所述像素单元输出发光控制信号的发光控制线；所述发光控制信号为周期性信号，用于在所述像素单元在接收所述数据电压之后控制所述像素单元周期性的发光；与奇数行像素单元连接的发光控制线连接于第一时钟信号端，与偶数行像素单元连接的发光控制线连接于第二时钟信号端，第一时钟信号端和第二时钟信号端输出的发光控制信号频率相同，相位相差180度。本发明的采用两路时钟信号作为OLED显示装置的发光控制信号，这样OLED显示装置的边框不再需要设置面积庞大的发光控制线驱动电路。因此本发明的技术方案可以有效减小OLED显示装置的边框宽度。

Description

OLED显示装置
技术领域
本发明涉及一种显示装置，尤指一种OLED显示装置。
背景技术
OLED显示器具有体积小，结构简单、自主发光、亮度高、画质好、可视角度大、功耗低及响应时间短等优点，因而引起广泛关注，极可能成为取代液晶的下一代显示技术。
图1所示为一种现有的OLED显示装置的结构图。如图1所示，该OLED显示装置包括呈矩阵排列的像素单元10。每行像素单元10连接有一条第一扫描线Gi、一条第二扫描线Gi-1以及一条发光控制线Ei(i为从1到n之间的整数)；每列像素单元10连接有一条数据线Dj(j为从1到m之间的整数)。图2所示为一种现有的像素驱动电路。像素单元10包含该像素驱动电路以及有机发光二极管。像素驱动电路的第一扫描端Sc连接于第一扫描线Gi，第二扫描端Sc-1连接于第二扫描线Gi-1，数据信号端Data连接于数据线Dj，发光控制端Emit连接于发光控制线Ei。图3所示为图2的像素电路在共工作过程中控制端的波形图。如图3所示，在像素单元10工作时，第一扫描线Gi通过第一扫描端Sc控制像素驱动电路接收来自数据线Dj的数据电压，随后发光控制线Ei控制像素驱动电路将数据电压转换为电流从而驱动有机发光二极管发光。
为了使发光控制线Ei可以向像素单元输出预定的信号，在现有技术中OLED显示装置通常包含一个用于向发光控制线Ei提供发光控制信号的发光控制线驱动模块13。在现有技术中每根发光控制线Ei的发光控制信号都和其他的发光控制线Ei的发光控制信号不同，因此现有技术中每根发光控制线Ei需要单独的发光控制线驱动电路提供发光控制信号，这会占用OLED显示装置边框的面积。另外随着OLED显示装置的面积不断增大，发光控制线驱动模块13需要驱动发光控制线的数量以及对发光控制线驱动模块13驱动能力的需求也随之增长，这进一步导致了发光控制线驱动模块13面积的增长，而光控制线驱动模块13的面积不断增长会导致OLED显示装置的边框进一步变宽。
发明内容
本发明的目的在于提供一种OLED显示装置，其能够解决发光控制线驱动模块占用大量边框面积的问题，从而减少OLED显示装置的边框宽度。
为了解决上述问题，本发明提供一种OLED显示装置其包括：呈阵列分布的像素单元，每列像素单元连接有用于向所述像素单元提供数据电压的数据线，每行像素单元连接有用于选中所述像素单元并且使其接收所述数据电压的第一扫描线，每行像素单元还连接有用于选中并且复位所述像素单元的第二扫描线；其特征在于：每行像素单元还连接有用于向所述像素单元输出发光控制信号的发光控制线，其中，与奇数行像素单元连接的发光控制线连接于第一时钟信号端，与偶数行像素单元连接的发光控制线连接于第二时钟信号端，第一时钟信号端和第二时钟信号端输出的二发光控制信号为频率相同的周期信号，二者相位相差为90度到180度之间的一个稳定值。
本发明的OLED显示装置的进一步改进在于：所述像素单元在所述第二扫描线提供的第二扫描信号的控制下进入复位状态，处于复位状态的所述像素单元清除其内部存储的数据电压。
本发明的OLED显示装置的进一步改进在于：当所述第二扫描信号线提供的第二扫描信号为低电平时，所述像素单元进入复位状态。
本发明的OLED显示装置的进一步改进在于：当所述像素单元处于复位状态时，所述像素单元接收自所述发光控制线的发光控制信号处于有效状态。
本发明的OLED显示装置的进一步改进在于：所述像素单元包括有机发光二极管，当所述像素单元处于复位状态时所述有机发光二极管两端的电压小于所述有机发光二极管的导通电压。
本发明的OLED显示装置的进一步改进在于：所述像素单元在所述第一扫描线提供的第一扫描信号的控制下进入数据电压写入状态，处于数据电压写入状态的所述像素单元接收并存储由所述数据线提供的所述数据电压。
本发明的OLED显示装置的进一步改进在于：所述像素单元包括一存储电容，所述像素单元将接受自所述数据线的所述数据电压存储于所述存储电容中。本发明的OLED显示装置的进一步改进在于：所述像素驱动电路包括一驱动晶体管；当所述像素单元处于数据电压写入过程时，将带有驱动晶体管的阈值电压的数据电压存储在存储电容中。
本发明的OLED显示装置的进一步改进在于：当所述第一扫描信号线提供的第一扫描信号为低电平时，所述像素单元进入数据电压写入状态。
本发明的OLED显示装置的进一步改进在于：当所述像素单元处于数据电压写入状态时，所述像素单元接收自所述发光控制线的所述发光控制信号处于无效状态。
本发明的OLED显示装置的进一步改进在于：当所述像素单元接收到的第一扫描信号为高电平且接收到的第二扫描信号为高电平时，所述像素单元处于发光显示状态，处于发光显示状态的像素单元在接受自所述发光控制线的发光控制信号的控制下驱动所述有机发光二极管发光。
本发明的OLED显示装置的进一步改进在于：当处于发光显示状态的所述像素单元接收到的所述发光控制信号有效时，所述像素驱动电路驱动所述有机发光二极管发光。
本发明的OLED显示装置的进一步改进在于：当所述像素单元驱动所述有机发光二极管发光时，所述有机发光二极管的亮度为所述像素单元存储的所述数据电压的函数。
本发明的OLED显示装置的进一步改进在于：当处于发光显示状态的所述像素单元接收到的所述发光控制信号处于无效状态时，所述有机发光二极管处于关断状态。
本发明的OLED显示装置的进一步改进在于：所述像素单元接收自所述发光控制线的所述发光控制信号为在有效状态和无效状态之间切换的周期信号。
本发明的OLED显示装置的进一步改进在于：所述发光控制信号的有效状态为低电平，无效状态为高电平。
本发明的OLED显示装置的进一步改进在于：所述发光控制信号为方波。
本发明的OLED显示装置的进一步改进在于：所述发光控制信号的占空比为0.5至0.9。
本发明的OLED显示装置的进一步改进在于：在OLED显示装置的工作过程中，任一时刻有且仅有一行所述像素单元处于复位状态。
本发明的OLED显示装置的进一步改进在于：在OLED显示装置的工作过程中，任一时刻有且仅有一行所述像素单元处于数据电压写入状态。
本发明的技术方案中将OLED显示装置采用两路时钟信号作为OLED显示装置的发光控制信号，以取代现有技术中的多路发光控制信号，这样OLED显示装置的边框不再需要设置面积庞大的发光控制线驱动电路。因此本发明的技术方案可以有效减小OLED显示装置的边框宽度。
附图说明
图1为一种现有的OLED显示装置的结构示意图；
图2所示为一种像素像素单元的电路图；
图3为图2的像素电路在共工作过程中各个控制端的波形图；
图4为本发明OLED显示装置的结构示意图；
图5为本发明OLED显示装置的像素单元在工作过程中控制信号的波形图；
图6为本发明OLED显示装置在工作过程中第一扫描线和发光控制线的信号波形图。
具体实施方式
下面结合附图以及具体实施方式对本发明作进一步详细的说明。
图4为一种本发明的OLED显示装置的结构示意图，如图4所示：本发明的OLED显示装置包括：n行m列呈阵列状分布的像素单元20；每列像素单元20连接有一条用于向像素单元20提供数据电压的数据线Dj(j为从1到m之间的整数)，数据线Dj由数据线驱动模块22驱动；每行像素单元20连接有一条第一扫描线Gi以及第二扫描线Gi-1(i为从1到n之间的整数)，第二扫描线Gi-1和第一扫描线Gi均由扫描线驱动模块21驱动；每行像素单元20还连接有一条发光控制线Ei(i为从1到n之间的整数)，其中连接于奇数行像素单元20的发光控制线Ei连接于第一时钟信号端CK1，与偶数行像素单元20连接的发光控制线Ei连接于第二时钟信号端CK2。
图2为一种像素单元的电路图，本实施例中OLED显示装置也可采用这种像素单元。如图2所示，该像素单元包括像素驱动电路和有机发光二极管。驱动电路包括第一扫描端Sc、第二扫描端Sc-1、发光控制端Emit以及数据信号端Data，像素驱动电路的和有机发光二极管串联连接。像素驱动电路的第一扫描端Sc连接于第一扫描线Gi，第二扫描端Sc-1连接于第二扫描线Gi-1，数据信号端Ddata连接于数据线Dj，发光控制端Emit连接于发光控制线Ei。
请继续参阅图5，图5所示为本发明实施例中该像素单元在工作过程中控制信号的波形图。如图2和图5所示，本实施例中像素单元在工作过程中不断重复下面3个过程：
Step 1.像素单元的复位过程：对应图5中的t1过程，在此过程中第二扫描端Sc-1接收到的第二扫描信号为低电平，发光控制端Emit收到的发光控制信号为低电平。第一扫描端Sc收到的第一扫描信号为高电平，于此同时第一电源ELVDD和复位电源Vin对存储电容Cst进行充电。像素单元在接收自第二扫描端Sc-1的第二扫描信号的控制下进入复位状态，进入复位状态后像素单元清除存储电容Cst内存储的数据电压。和图3所示的现有技术不同，在本实施例的复位过程中发光控制端Emit接收到的发光控制信号处于有效状态(低电平)，这样会导致第三晶体管T3和第四晶体管T4的导通，但是在像素单元20的复位过程中第三晶体管T3和第四晶体管T4的导通不会影响像素单元的20的正常运行。在第二扫描端Sc-1的控制下第六晶体管T6以及第七晶体管T7也处于导通状态，第七晶体管T7的导通使得复位电源Vin和有机发光二极管的阳极之间导通。在本实施例中复位电源Vin的电压为-2V，而连接于有机发光二极管阴极的第二电源Elvss的的电压为-3V，由此可知此时有机发光二极管两端的电压小于有机发光二极管的正向导通的阈值电压。因此虽然在像素单元的复位过程中发光控制端En的发光控制信号为低电平，处于有效状态，但是在此过程中程中有机发光二极管不发光。
Step 2.数据电压的写入过程：对应图5中的t2过程，此时第二扫描端Sc-1接收到的第二扫描信号为高电平，发光控制端Emit收到发光控制信号为高电平，第一扫描端Sc收到的第一扫描信号为低电平。像素单元在接收自第一扫描端Sc的第一扫描信号的控制下进入数据电压写入状态，在此过程中像素驱动电路的数据信号端Data接收来自数据线Dj的数据电压，并且将数据电压存储于存储电容Cst中。在数据电压的写入过程中发光控制端Emit接收到的发光控制信号处于无效状态。像素单元还包括一驱动晶体管T2，根据TFT的特性，可以把带有驱动晶体管T2的阈值电压Vth的数据电压存储在存储电容Cst中。
Step 3.发光显示过程：对应图5中的t3过程，此时第一扫描端Sc的第一扫描信号为高电平，第二扫描端Sc-1收到的第二扫描信号为高电平，在第一扫描信号和第二扫描信号的控制下，像素单元进入发光显示状态。发光控制端Emit从发光控制线接收到的发光控制信号为方波，因此发光控制信号周期性的进入有效状态，当发光控制信号有效时，处于发光显示状态的像素单元的像素驱动电路驱动其内部的有机发光二极管发光。在此过程中存储电容Cst中存储的数据电压和驱动晶体管T2的阈值电压Vth叠加至驱动晶体管T2的栅极。发光控制信号处于低电平时为有效状态，高电平时为无效状态。当发光控制信号处于有效状态时，第三晶体管T3和第四晶体管T4处于导通状态，流过驱动晶体管T2源极和漏极之间的电流大小由存储电容Cst中存储的数据电压决定；由于流过有机发光二极管的电流和流过驱动晶体管T2源极和漏极之间的电流大小相同，所以当发光控制信号有效时，有机发光二极管的亮度由存储电容Cst中存储的数据电压决定。综上所述当有机发光二极管发光时，有机发光二极管的亮度为存储电容Cst中存储的数据电压的函数。当发光控制信号处于无效状态时，由于第三晶体管T3和第四晶体管T4处于截止状态，电流无法通过驱动晶体管T2输出到有机发光二极管，有机发光二极管处于关断状态。所以当发光控制信号无效时有机发光二极管不发光。
请继续参阅图6，图6为本发明OLED显示装置中第一扫描线Gi和发光控制线Ei上的波形图。如图5和图6所示：在OLED显示装置的工作过程中，OLED显示装置中的任意的第k行像素单元20都在依次重复上述3个过程。从整体来看，OLED显示装置的第一扫描线Gi依次逐行扫描并且选中像素单元20，被第一扫描线Gi选中的像素单元20处于数据电压写入过程。若第k行像素单元20正处于数据电压的写入过程，那么同一时刻第k-1行像素单元20正出于发光显示过程，第k+1行像素单元20处于像素单元的复位过程。在OLED显示装置中任意时刻有且仅有一行像素单元处于复位状态，有且仅有一行像素单元处于数据电压写入状态。
通过图6的波形图以及上述关于像素单元20的运行过程的分析可知，第k-1行像素单元20的发光控制信号和第k+1行像素单元20的发光控制信号可以采用频率和相位均相同的方波。因此本发明的OLED显示装置将奇数行像素单元20的发光控制线Ei连接于第一时钟信号端CK1，将偶数行像素单元20的发光控制线连接于第二时钟信号端CK2。相邻行像素单元20的发光控制信号的相位相差一固定角度，两者相位相差在90到180度之间，所以第一时钟信号端CK1和第二时钟信号端CK2输出的发光控制信号的频率相同但相位相差90到180度之间的一个角度，在本实施例中为相差180度。本发明采用第一时钟信号端CK1和第二时钟信号端CK2作为发光控制线Ei的驱动端，使得OLED显示装置只需要向发光控制线Ei提供两路具有恒定相位差的发光控制信号，这样可以大大减少发光线驱动电路占用的面积，从而减少OLED显示装置的边框宽度。
通过上面对像素单元的分析可知：像素单元20正常运行的一个必要条件是：像素单元20在Step 2.数据电压的写入过程中发光控制信号需要保持在无效状态，即高电平状态。在满足这个必要条件的情况下，像素单元20在其他时刻发光控制端的发光控制信号不一定要保持在有效状态。因此我们可以调整发光控制信号的占空比，通过调整发光控制信号的占空比可以调整发光控制信号处于有效状态的总时间，进而调节OLED显示装置的亮度。由于上述必要条件的限制，发光控制信号的占空比的下限为0.5；为了保证OLED显示装置显示的图像能够被人眼正常识别本实施例中发光控制信号的上限为0.9。通过调整发光控制信号的占空比的方式可以更加灵活的调整OLED显示装置的灰阶。
以上结合附图实施例对本发明进行了详细说明，本领域中普通技术人员可根据上述说明对本发明做出种种变化例。因而，实施例中的某些细节不应构成对本发明的限定，本发明将以所附权利要求书界定的范围作为本发明的保护范围。

Claims (20)

1.一种OLED显示装置，包括：呈阵列分布的像素单元，所述像素单元包括像素驱动电路和有机发光二极管，每列像素单元连接有用于向所述像素单元提供数据电压的数据线，每行像素单元连接有用于选中所述像素单元并且使其接收所述数据电压的第一扫描线，每行像素单元还连接有用于选中并且复位所述像素单元的第二扫描线；其特征在于：每行像素单元还连接有用于向所述像素单元输出发光控制信号的发光控制线，其中，与奇数行像素单元连接的发光控制线连接于第一时钟信号端，与偶数行像素单元连接的发光控制线连接于第二时钟信号端，第一时钟信号端和第二时钟信号端输出的二发光控制信号为频率相同的周期信号，二者相位相差为90度到180度之间的一个稳定值。
2.如权利要求1所述的OLED显示装置，其特征在于：所述像素单元在所述第二扫描线提供的第二扫描信号的控制下进入复位状态，处于复位状态的所述像素单元清除其内部存储的数据电压。
3.如权利要求2所述的OLED显示装置，其特征在于：当所述第二扫描线提供的第二扫描信号为低电平时，所述像素单元进入复位状态。
4.如权利要求3所述的OLED显示装置，其特征在于：当所述像素单元处于复位状态时，所述像素单元接收自所述发光控制线的发光控制信号处于有效状态。
5.如权利要求4所述的OLED显示装置，其特征在于：当所述像素单元处于复位状态时所述有机发光二极管两端的电压小于所述有机发光二极管的导通阈值电压。
6.如权利要求2所述的OLED显示装置，其特征在于：所述像素单元在所述第一扫描线提供的第一扫描信号的控制下进入数据电压写入状态，处于数据电压写入状态的所述像素单元接收并存储由所述数据线提供的所述数据电压。
7.如权利要求6所述的OLED显示装置，其特征在于：所述像素驱动电路包括一存储电容，所述像素单元将接受自所述数据线的所述数据电压存储于所述存储电容中。
8.如权利要求7所述的OLED显示装置，其特征在于：所述像素驱动电路包括一驱动晶体管；当所述像素单元处于数据电压写入过程时，将带有驱动晶体管的阈值电压的数据电压存储在存储电容中。
9.如权利要求6所述的OLED显示装置，其特征在于：当所述第一扫描线提供的第一扫描信号为低电平时，所述像素单元进入数据电压写入状态。
10.如权利要求6所述的OLED显示装置，其特征在于：当所述像素单元处于数据电压写入状态时，所述像素单元接收自所述发光控制线的所述发光控制信号处于无效状态。
11.如权利要求6所述的OLED显示装置，其特征在于：当所述像素单元接收到的第一扫描信号为高电平且接收到的第二扫描信号为高电平时，所述像素单元处于发光显示状态，处于发光显示状态的像素单元在接受自所述发光控制线的发光控制信号的控制下驱动所述有机发光二极管发光。
12.如权利要求11所述的OLED显示装置，其特征在于：当处于发光显示状态的所述像素单元接收到的所述发光控制信号有效时，所述像素驱动电路驱动所述有机发光二极管发光。
13.如权利要求12所述的OLED显示装置，其特征在于：当所述像素驱动电路驱动所述有机发光二极管发光时，所述有机发光二极管的亮度为所述像素单元存储的所述数据电压的函数。
14.如权利要求12所述的OLED显示装置，其特征在于：当处于发光显示状态的所述像素单元接收到的所述发光控制信号处于无效状态时，所述有机发光二极管处于关断状态。
15.如权利要求14所述的OLED显示装置，其特征在于：所述像素单元接收自所述发光控制线的所述发光控制信号为在有效状态和无效状态之间切换的周期信号。
16.如权利要求2至15任一项所述的OLED显示装置，其特征在于：所述发光控制信号的有效状态为低电平，无效状态为高电平。
17.如权利要求16所述的OLED显示装置，其特征在于：所述发光控制信号为方波。
18.如权利要求17所述的OLED显示装置，其特征在于：所述发光控制信号的占空比为0.5至0.9。
19.如权利要求2所述的OLED显示装置，其特征在于：在OLED显示装置的工作过程中，任一时刻有且仅有一行所述像素单元处于复位状态。
20.如权利要求6所述的OLED显示装置，其特征在于：在OLED显示装置的工作过程中，任一时刻有且仅有一行所述像素单元处于数据电压写入状态。
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