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CN1771527A - 显示设备 - Google Patents

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Publication number
CN1771527A
CN1771527A CNA2004800094075A CN200480009407A CN1771527A CN 1771527 A CN1771527 A CN 1771527A CN A2004800094075 A CNA2004800094075 A CN A2004800094075A CN 200480009407 A CN200480009407 A CN 200480009407A CN 1771527 A CN1771527 A CN 1771527A
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Prior art keywords
display device
light emitting
display
level
time interval
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A·吉拉多
M·T·约翰逊
W·P·M·M·詹斯
R·洛斯
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Koninklijke Philips NV
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Koninklijke Philips Electronics NV
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Publication of CN1771527A publication Critical patent/CN1771527A/zh
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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
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    • 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]
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    • 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
    • G09G3/2007—Display of intermediate tones
    • G09G3/2018—Display of intermediate tones by time modulation using two or more time intervals
    • G09G3/2022—Display of intermediate tones by time modulation using two or more time intervals using sub-frames
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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]
    • 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
    • G09G3/3233—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
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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]
    • 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
    • G09G3/3233—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
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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)
  • Control Of El Displays (AREA)
  • Electroluminescent Light Sources (AREA)

Abstract

显示设备(6)包括显示器(2)和产生装置(10、8)。该显示器(2)具有多个发光元件(3)和用于将脉宽调制(PWM)信号提供到发光元件(3)的数据线(13)。该产生装置(10、8)被耦合到数据线(13)，用于在帧周期的时间间隔(SF)内至少产生第一时间间隔(SF)内发光元件(3)的第一非零发射电平(L(V1；C1；I1))以及第二时间间隔(SF)内发光元件(3)的第二非零发射电平(L(V2；C2；I2))。

Description

显示设备
本发明涉及包括具有多个发光元件的显示器的显示设备。本发明还涉及包括该显示设备的电子设备以及驱动显示器的方法。
使用衬底上或衬底上方的发光元件或像素的显示设备正变得越来越流行。这些发光元件可以为包括在显示像素或者形成显示像素(排列成行和列矩阵)的发光二极管(LED)。这些LED中使用的材料适于在电流流过时产生光线，例如特殊的聚合物(PLED)材料或者有机(OLED)材料。因此必须排列这些LED，从而驱动电流流过这些发光材料。典型地，可以分为无源驱动矩阵显示和有源驱动矩阵显示。对于有源矩阵显示，显示像素本身包括诸如一个或者多个晶体管的有源电路。
在有源矩阵显示中，对于例如显示均匀性而言，晶体管参数变化成为重要的问题。使晶体管在适当大的电流下工作，这些LED的光发射对晶体管阈值电压变化的敏感度降低，其中该阈值电压的变化已经被认为是显示不均匀的主要原因。如果LED工作于只有少数的亮度电平，每个亮度对应于特定的电流电平，这种工作方案称为数字驱动。
众所周知，由于采用数字驱动只能得到少数的亮度电平，所以可以使用脉宽调制(PWM)形成更多的灰度电平。例如，可以在帧周期内许多子域的任意一个子域期间，根据预期的灰度电平而“开启”或者“关闭”该显示的发光元件。该子域为一个帧周期内的时间间隔。
然而，当对包括与发光元件的行相关的大量选择线的大尺寸显示器一次寻址一行时，用于寻址或者选择一行的可获得的寻址时间为亚微秒量级。为了解决这些非常短的寻址时间，优选采用多线寻址(MLA)方案。MLA方案有时也称为组合线或行寻址方法。在MLA方案中，通过适当的算法，最小化各子域之间的空载时间(dead time)。该方法例如在EP专利申请号01204541.5中得到公开。在本说明书中，认为MLA是PWM寻址的一种，即PWM包括MLA。
PWM技术的问题在于并未提供用于显示的灰度级电平的最优范围。
本发明的目标是显著增大PWM寻址显示的灰度级电平的数目。
通过提供一种显示设备而实现该目标，其中该显示设备包括：
具有多个发光元件的显示器，和用于向发光元件提供脉宽调制(PWM)信号的数据线；以及
耦合到数据线的装置，从而在帧周期的时间间隔期间，至少在第一时间间隔内产生发光元件的第一非零发射电平并在第二时间间隔内产生第二非零发射电平。
在该第一和第二非零电平之后，可能存在一个零电平和附加的非零电平。
当需要具有更大权重的子域时，不是增大该时间间隔，而是应该采用比第一发射电平高的第二发射电平，该第二发射电平可以产生具有更大权重的子域而不增大该时间间隔。
由于子域的持续时间由此得到缩短，在一个帧周期内可以产生更多的子域，导致用于显示的灰度级电平的数目增大。该产生装置可包括数据驱动器和控制单元，用于接收关于待显示图像的信息，以及确定用于驱动该数据驱动器的定时信号和驱动信号。该显示器优选地为有源矩阵显示器。这种显示器允许多个发光元件的一部分发射光线，而其余部分正被寻址或者擦除。由于每个发光元件包括有源元件，诸如与存储元件(例如电容器)结合的薄膜晶体管，使得这一点成为可能。该矩阵显示器可以为有机LED或者聚合物LED显示器。
在一个实施例中运用了多线寻址方案，这导致帧周期内空载时间的进一步降低，由此允许更多的时间间隔用于产生光线，并因此可以产生更多的灰度电平。
该产生装置还包括用于选择多个发光元件的一部分的行选择电路。
优选地，PWM寻址方案的时间间隔具有二进制权重持续时间。这些时间间隔可以按照其持续时间排列成混杂顺序，即持续时间长的时间间隔和持续时间短的时间间隔可相互毗邻，从而获得对帧周期的最佳使用。优选地，各个发射电平和具有二进制权重持续时间的一组时间间隔相关联。
在本发明的一个实施例中，通过数据线提供发光元件的发射电平。优选地，以顺序模式完成这一点，其中在帧周期内，首先对第一发射电平依次处理所有的时间间隔，随后对第二发射电平依次处理所有的时间间隔等。该驱动方案对电压编程和电流编程的发光元件都适用。
在混杂模式中，和发射电平相关联的时间间隔可以在帧周期内按照要求分配，例如，各个时间间隔可以交替地采用第一发射电平和第二发射电平。该驱动方案对电压编程和电流编程的发光元件都适用。对于电流编程发光元件，在本实施例中优选采用多个独立的电流源，这是因为发光元件的发射电平在帧周期内经常改变。在这种情况下，单个电流源较不适合，这是因为电流源通常无法在短时间内充分精确地在各种电流幅度之间进行切换。
对于电流可编程发光元件，优选在施加电流之前将数据线设在适当的电压电平，其目的为克服由数据线内寄生电容引起的延迟。
使用电源线将第一或者第二电源电压耦合到发光元件的驱动方案尤其适用于电压编程发光元件。
本发明进一步涉及包括在前面段落中描述的显示设备的电子设备。该电子设备可涉及手持式设备，例如移动电话、个人数字助理(PDA)、或者便携电脑，还涉及诸如个人计算机、计算机监视器、电视机或者例如汽车仪表板上的显示器的设备。
将参考附图进一步阐述本发明，其中附图示出了根据本发明的优选实施例。将会了解到，根据本发明的设备和方法不以任何方式受限于这些特殊优选实施例。附图中：
图1示出了包括根据本发明实施例的显示器的电子设备；
图2示出了用于根据本发明实施例的有源矩阵显示的显示设备；
图3示出了表示根据现有技术的脉宽调制(PWM)的示意性时序图；
图4示出了表示采用了根据现有技术的MLA方案的脉宽调制的示意性时序图；
图5示出了在采用混杂模式多电平电源寻址(MPA)的电压编程像素电路中本发明的第一实施例；
图6示出了表示图5所示实施例的采用多电平电源寻址(MPA)的脉宽调制的示意性时序图；
图7示出了本发明的第二实施例的概念性时序图，该实施例采用了顺序模式的多电平电源寻址(MPA)；
图8示出了电压编程像素电路中的本发明第三实施例，该实施例采用了混杂模式的多电平列寻址(MCA)；
图9示出了表示图8所示实施例的采用多电平列寻址(MCA)的脉宽调制的示意性时序图；
图10示出了电流编程像素电路中的本发明第四实施例；
图11示出了在修改的电流编程像素电路中的本发明第五实施例。不同附图中相同的参考数字表示相同的元件。
图1示出了含有显示器2的电子设备1，其中显示器2具有排列成行4和列5矩阵的多个发光元件或显示像素3。
图2示出了显示设备6的示意图，其中显示设备6包括图1所示的电子设备1的显示器2。该显示器2包括行选择电路7和数据驱动器8。通过线9接收且将在显示器2上显示的信息或者数据诸如(视频)图像被输入到控制单元10，随后控制单元10将该信息或数据通过线11传输到数据驱动器8的适当部分。由行选择电路7通过选择线12执行对显示像素3的行4的选择。通过数据线13将数据从数据驱动器8写入显示像素3。
此外，控制单元10通过电源线14控制显示像素3的电源。
图3展示了用于形成显示技术中灰度级电平的脉宽调制(PWM)的示意性时序图。在图3中，在垂直方向上只示出了显示器2的8个行4，而在水平方向示出了作为时间函数的各行的状态。仅示出了帧周期的一部分。根据待显示的灰度级电平的数目，将帧周期划分成持续时间不同的多个子域或时间间隔SF。图3仅示出了对于该8个行4的帧周期的两个时间间隔或者子域，并用SF1和SF2表示。在时间间隔SF内，可以辨别出显示像素3的多个状态，即寻址(阴影线区块)，燃烧(黑色区块)，擦除(打点的区块)和空载时间(白色区块)。如果帧周期的时间间隔SF具有二进制权重分布，该时间间隔代表多个灰度级电平的位表示。即，如果帧周期被划分成6个二进制权重时间间隔SF1...6，SF1表示灰度级位电平1，SF2表示灰度级位电平2，SF3、SF4、SF5及SF6则分别表示灰度级电平4、8、16和32，从而产生共26＝64个可能的灰度级电平(＝6位)。
对于包括480个行4的显示器2，具有64个灰度级电平的20ms帧时间，子域SF1可获得的时间间隔为0.65微秒。
图4示出了结合PWM采用多线行寻址(MLA)的时序图。可以清楚地看出，在MLA中，对于行4的时间间隔SF之间的空载时间数量是不同的，通过采用适当的算法可以使其最小化。因此可以更加有效地利用该帧周期内的有效时间。注意，优选地将帧周期内的时间间隔搅乱或混杂，从而获得最有效的结果。这意味着在先前段落的示例中，时间间隔的顺序不一定为SF1、SF2、SF3、SF4、SF5、SF6，而是可以为例如SF3、SF1、SF6、SF4、SF2、SF5。
图5示出了电压编程像素电路15中本发明的第一实施例。仅示出了显示器2的单个显示像素3，包括晶体管T1(画成开关)和T2、电容器C和LED。可以通过选择线12选择显示像素3，并通过数据线13向显示像素3提供数据。通过电源线14向显示像素3供电。在右侧的图中示出了设于选择线12上的选择信号，其中开态依次指寻址AD和擦除ER。设于数据线13上的数据是可以使晶体管T2完全开启或者完全关闭的电压，在右侧的图中用“off”和“on”表示，即T2用作开关，该LED的光发射电平取决于电源线14上所提供的电压。不同的电压产生LED的不同发射电平。这个效应用于提高帧周期内灰度级电平的数目。在图5中，PWM信号通过选择线12被提供到显示像素3，该显示像素3首先在第一时间间隔SF1内被设成用V1表示的第一发射状态(对应于第一发射电平)，在同一持续时间内随后的时间间隔SF1内被设成用V2表示的第二发射状态(对应于第二发射电平)。右侧的图中示出了这种情况。可以在下一个时间间隔SF2内重复(未示出)这些事件，其中随后在时间间隔SF2内再次在V1和V2下进行燃烧。如果在电源线14上存在n个电源电平，即多电平电源寻址(MPA)，一个帧周期内N个时间间隔的顺序可以为例如SF1(V1)、SF1(V2)、SF1(V3)...SF1(Vn)；SF2(V1)...SF2(Vn)；...，SFN(V1)...SFN(Vn)。这是混杂模式的示例，其中重复改变该LED的发射状态。
在MPA方法中，单个时间间隔SF实际上使用了n次，而非只使用1次。因此，灰度级电平的位数最大可以增大n倍。图6展示了8个行4的显示器2的时序图，其中在SF1内，显示像素3首先采用第一发射状态V1(浅灰色区块)，接着在随后的相同时间间隔SF1内采用第二发射状态V2(黑色区块)。
在图7中，展示了单个行4的16灰度级电平(＝4位)PWM寻址方案中采用了顺序模式的MPA的概念性时序图。在该顺序模式中，首先在选择线12上提供第一发射状态V1的所有时间间隔SF，随后提供第二发射状态V2的所有时间间隔SF。再次注意，不一定根据时间长度对时间间隔SF排序，如果可以更有效地使用该帧周期则可以将这些时间间隔SF混杂。在图7中，各数字表示与时间间隔SF1...SF4相关联的灰度级电平的数目。选择第二发射状态V2，使得第二发射状态V2中的显示像素3的光发射电平L(V2)等于该帧周期内灰度级电平的数目(即16)乘以第一发射状态中发光元件的光发射电平L(V1)。在图7中上面的时序图中，采用了顺序模式的MPA。为了获得例如100个灰度级电平，在一个帧周期内将选择线12上的阴影线位提供到显示像素3是足够的。一个帧周期内灰度电平的最大数目为256。为了比较，图7中下面的时序图展示了无MPA的情形。这种情况下，相同数量的时间只允许一个帧周期内出现32个灰度级电平。更一般地，如果电源线14上具有n个电源电平，即多电平电源寻址(MPA)，则在顺序模式中一个帧周期内N个时间间隔的顺序为SF1(V1)、SF2(V1)、SF3(V1)...SFN(V1)；SF1(V2)...SFN(V2)；...，SF1(Vn)...SFN(Vn)。
图8示出了电压编程像素电路15中的本发明第三实施例，该实施例采用了混杂模式中的多电平列寻址(MCA)。如右侧的图所示，选择信号再次施加于选择线12。在该实施例中，如右侧的图所示，改变数据线13上的列电压会创建附加的灰度级电平。对于显示像素3，施加在电源线14上的电源电平保持不变。然而注意，在一个寻址方案中可以同时采用MPA和MCA。在该实施例中使用了半数字的方法，其中可以将有限数量的电压电平(包括用于关闭晶体管T2的电压电平)施加到晶体管T2的栅。因此T2不再只用作开关(图5中为这种情形)，而是成为半模拟元件，使得在数据电平C1时该LED为电流驱动，而在数据电平C2时T2仍用作开关。注意，从LED退化的角度而言这种状态是有益的，因为使用目前采用的聚合物材料时，电压驱动LED的寿命更短。
LED的光发射状态是由通过数据线13施加在T2栅极上的电压数目决定的。类似图5，在图8中的优选实施例通过在数据线13上在每个时间间隔SF内为显示像素3提供与C1相关联的第一发射状态和与C2相关联的第二发射状态，从而使灰度级电平的数目翻倍，。优选选择电平C1和C2，使得LED在状态C2下的光发射电平L(C2)等于灰度级电平的数目乘以在状态C1下的光发射电平L(C1)。如果例如PWM为4位(16个灰度级电平)，采用多电平列寻址(MCA)可产生256个灰度级电平。通常，如果数据线13上存在n个电压电平，即多电平列寻址(MCA)，则对于混杂模式，一个帧周期内N个时间间隔的顺序可以为例如SF1(C1)、SF1(C2)、SF1(C3)...SF1(Cn)；SF2(C1)...SF2(Cn)；...，SFN(C1)...SFN(Cn)。图9示出了采用PWM-MLA-MCA寻址方案的时序图。浅灰色区块代表第一发射状态C1，而黑色区块代表第二发射状态C2。
类似图5，图8也可以用于顺序模式，由此得到顺序为SF1(C1)、SF2(C1)、SF3(C1)...SFN(C1)；SF1(C2)...SFN(C2)；...；SF1(Cn)...SFN(Cn)的一般情形。
多列寻址(MCA)方案也可以用于电流可编程像素电路。图10示出了具有开关电流镜电路的已知的电流编程像素电路16。使用其它类型的电流镜电路也可使得电流镜工作。数据线13可以用于提供n个电流电平I1....In，从而将该LED激活为帧周期内的n个不同发射状态。零电平可以为电压电平(对于高速而言是优选的)，或者可以为在寻址或者擦除期间使该LED失效的电流电平。在寻址或擦除期间，开关晶体管T0和T3开启(on)，开关晶体管T4关闭(off)，驱动晶体管T11被编程以驱动电流Ii。在燃烧周期内，T0和T3关闭，T4开启，T11向LED发送电流Ii。
在优选实施例中n＝2，即电流I1和显示像素的第一发射状态相关联，电流I2和第二发射状态相关联。优选地采用电流I2，使得第二发射状态的光发射电平L(I2)等于第一发射状态的光发射水L(I1)乘以第一发射状态的灰度级电平的数目。根据图10的电路优选工作于顺序模式，由此得到的顺序为SF1(I1)、SF2(I1)、SF3(I1)...SFN(I1)；SF1(I2)...SFN(I2)；...，SF1(In)...SFN(In)。图10所示实施例较不适用于混杂模式，这是因为电流源通常无法快速地在精确电流电平之间切换。
对于电流可编程像素电路，为了在采用MCA方案时能使用混杂模式，优选使用多个独立的电流源，这些电流源在数据线13上提供适当的电流幅度。图11中示出了这种修改的电流可编程像素电路17，该电路具有在数据线13上提供电流I1和I2的两个独立电流源。开关晶体管S1和S2(通过线18受到控制单元10的控制)在适当的时间间隔SF内分别提供电流I1和I2。可以在转储单元19内转储其它电流。对于混杂模式的4位PWM寻址方案，该方案会读取SF3(I1)、SF3(I2)、SF2(I1)、SF2(I2)、SF4(I1)、SF4(I2)、SF1(I1)、SF1(I2)。注意，在该顺序中，各时间间隔相对于其持续时间进行混杂，优选采取这种顺序以有效利用该帧周期。
已知的是电流可编程像素电路16、17受到由于寄生耦合引起的定时问题的困扰。当向显示像素3写入电流脉冲时，首先对与显示像素3的列5相对应的数据线13的寄生电容进行充电。该电容可能具有非常高的电平，并依赖于显示器2的尺寸。图10和11所示的电流可编程像素电路16、17因此可能适用于对数据线13预充电，即在提供电流之前将数据线13至于适当的电压。数据驱动器8可以通过控制单元10管理该预充电。
应该注意的是，上述实施例阐述而非限制本发明，在不离开所附权利要求范围的情况下，本领域技术人员可以设计许多备选实施例。在各权利要求中，圆括号内的参考符号不应被理解成是对该权利要求的限制。使用动词“包括”及其变形并不排除存在除了权利要求中所陈述的元件或步骤之外的元件或步骤。元件前面的“一”或“一个”并不排除存在多个该元件。通过包括多个特定元件的硬件并采用适当编程的计算机可以实施本发明。在列举诸多装置的设备权利要求中，许多这种装置可以采用相同的一件硬件。在互相不同的多个权利要求中陈述特定措施的这一纯粹事实并不说明这些措施的组合使用不具有优越性。

Claims (11)

1.显示设备(6)，包括：
具有多个发光元件(3)的显示器(2)，和用于向发光元件(3)提供脉宽调制(PWM)信号的数据线(13)；以及
耦合到数据线(13)的装置(10、8)，从而在帧周期的时间间隔(SF)期间，至少在第一时间间隔(SF)内产生发光元件(3)的第一非零发射电平(L(V1；C1；I1))并在第二时间间隔(SF)内产生第二非零发射电平(L(V2；C2；I2))。
2.根据权利要求1的显示设备(6)，其中该显示器(2)还包括选择线(12)，每个选择线(12)耦合到多个发光元件(3)的一部分，产生装置(10、8)另外耦合到选择线(12)，从而将多线寻址方案运用于数据线(13)和选择线(L2)。
3.根据权利要求1的显示设备(6)，其中产生装置(10、8)用于产生任意顺序的基本上为二进制权重持续时间的时间间隔(SF)。
4.根据权利要求1的显示设备(6)，其中产生装置(10、8)用于通过数据线(13)产生顺序模式的第一(L(V1；C1；I1))和第二发射电平L(V2；C2；I2)。
5.根据权利要求1的显示设备(6)，其中该产生装置(10、8)用于通过数据线(13)产生混杂模式的第一(L(V1；C1；I1))和第二发射电平(L(V2；C2；I2))。
6.根据权利要求3的显示设备(6)，其中该产生装置(10、8)包括控制单元(10)和数据驱动器(8)，该数据驱动器(8)包括用于产生第一发射电平(L(I1))的第一电流源(I1)和用于产生第二发射电平的(L(I2))的第二电流源(I2)。
7.根据权利要求5的显示设备(6)，其中该产生装置(10、8)用于在将电流源(I1、I2)之一耦合到数据线(13)之一之前对数据线(13)预先充电。
8.根据权利要求1的显示设备(6)，进一步包括分别将第一电源电压(V1)耦合到多个发光元件(3)以产生第一发射电平(L(V1))以及将第二电源电压(V2)耦合到多个发光元件(3)以产生第二发射电平(L(V2))的电源线(14)。
9.根据权利要求1的显示设备(6)，其中该产生装置(10、8)用于产生电平基本上等于第一发射电平(L(V1；C1；I1))乘以多个可选择时间间隔(SF)组合的第二发射电平(L(V2；C2；I2))。
10.包括根据权利要求1的显示设备(6)的电子设备(1)。
11.用于驱动显示设备(6)的方法，所述显示设备(6)包括具有多个发光元件(3)的显示器(2)和耦合到发光元件(3)的数据线(13)，该方法包括步骤：
向数据线(13)提供脉宽调制(PWM)信号；以及
在帧周期的时间间隔(SF)内，至少产生与脉宽调制(PWM)信号同步的第一时间间隔(SF)内发光元件(3)的第一非零发射电平(L(V1；C1；I1))以及第二时间间隔(SF)内发光元件(3)的第二非零发射电平(L(V2；C2；I2))。
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US20060250334A1 (en) 2006-11-09
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