Temperature compensation of ferro-electric liquid crystal displays
    1.
    发明授权
    Temperature compensation of ferro-electric liquid crystal displays 失效
    铁电液晶显示器的温度补偿

    公开(公告)号:US5825344A

    公开(公告)日:1998-10-20

    申请号:US704785

    申请日:1996-09-26

    IPC分类号: G02F1/133 G09G3/36

    摘要: The invention provides an addressing scheme with temperature compensation for temperature induced changes in liquid crystal material switching parameters. Temperature compensation is provided by measuring liquid crystal temperature, and varying the length of strobe waveforms accordingly. A ferroelectric liquid crystal cell is addressed by row and column electrodes forming an x,y matrix of display elements. A strobe waveform is applied to each row in sequence whilst appropriate data waveforms are applied to all the column electrodes. At each display element, the material receives an addressing waveform to switch it to one of its two switched states depending upon the polarity of the addressing waveform. The data waveforms are, e.g., alternating positive and negative pulses of period 2 ts. The strobe waveform has a zero for one time period ts followed by a unipolar voltage pulse of significant duration, e.g., equal to or greater than 0.25 ts or more. This may result in an overlapping of addressing in adjacent rows, e.g., the end of a strobe pulse on one row overlaps with the beginning of a strobe pulse on the next row. The display elements may be switched into one of their two states by one of two strobe pulses of opposite polarity. Alternatively, a blanking pulse may switch all elements to one state and a strobe used to switch selected elements to the other state.

    摘要翻译: PCT No.PCT / GB95 / 00417 Sec。 371日期1996年9月26日 102(e)日期1996年9月26日PCT提交1995年2月28日PCT公布。 出版物WO95 / 24715 PCT 日期1995年9月14日本发明提供了一种用于温度补偿的寻址方案,用于温度引起的液晶材料切换参数的变化。 通过测量液晶温度和相应地改变选通波形的长度来提供温度补偿。 铁电液晶单元通过形成显示元件的x,y矩阵的行和列电极来寻址。 每个行按顺序施加选通波形,同时将适当的数据波形应用于所有的列电极。 在每个显示元件上,材料接收寻址波形,以根据寻址波形的极性将其切换到其两个切换状态之一。 数据波形例如是周期2 ts的交替的正脉冲和负脉冲。 频闪波形在一个时间段ts之后具有零,随后是显着持续时间的单极电压脉冲,例如等于或大于0.25tts或更大。 这可能导致相邻行中寻址的重叠,例如,一行上的选通脉冲的结束与下一行上的选通脉冲的开始重叠。 显示元件可以通过相反极性的两个选通脉冲之一切换到它们的两个状态之一。 或者,消隐脉冲可以将所有元件切换到一个状态,并且选通用于将所选元件切换到另一状态。

    Multiplex addressing of ferro-electric liquid crystal displays
    2.
    发明授权
    Multiplex addressing of ferro-electric liquid crystal displays 失效
    铁电液晶显示器的多路寻址

    公开(公告)号:US5724060A

    公开(公告)日:1998-03-03

    申请号:US505200

    申请日:1995-08-14

    IPC分类号: G02F1/133 G09G3/36

    摘要: The invention provides a ferro-electric liquid crystal display (FLCDs) with reduced voltages requirements for driver circuits. This enables standard drivers circuits designed to rms address twisted nematic type of displays, to be used for FLCDs. Displays are formed by cells containing smectic liquid crystal material. The cell walls are surface treated and carry e.g. row and column electrodes forming an x,y matrix of addressable display elements. The smectic liquid crystal material switches between two states upon application of a dc pulse of appropriate amplitude, polarity, and time. Addressing waveforms are strobe waveforms, e.g. two pulses of opposite polarity in successive time slots, applied to each row in turn. Data waveforms are, e.g. dc pulses of alternate polarity with each pulse lasting one time slot ts. Two data waveforms are needed to switch between the two states; one data waveform is the inverse of the other. Typically a strobe waveform pulse may be 50 volts. In the invention a voltage reduction waveform (VRW) is added to both strobe and data waveforms. This has the effect of reducing the maximum amplitude of voltage needed by the driver circuits, whilst leaving the resultant voltage appearing at a display element at the same value as if VRW were not used. With a reduced voltage requirement, driver circuits previously used for relatively low voltage menatic material type of displays can be used to switch smectic materials.

    摘要翻译: PCT No.PCT / GB94 / 00150 Sec。 371日期1995年8月14日 102(e)日期1995年8月14日PCT 1994年1月26日PCT PCT。 公开号WO94 / 18665 日期1994年8月18日本发明提供了一种对驱动电路具有降低的电压要求的铁电液晶显示器(FLCD)。 这使得设计用于符合地址扭转向列型显示器的标准驱动器电路用于FLCD。 显示器由含有近晶液晶材料的电池形成。 细胞壁被表面处理并携带。 行和列电极形成可寻址显示元件的x,y矩阵。 当应用具有适当幅度,极性和时间的直流脉冲时,近晶体液晶材料在两种状态之间切换。 寻址波形是选通波形,例如。 在连续的时隙中两个相反极性的脉冲依次应用于每一行。 数据波形例如。 具有交替极性的直流脉冲,每个脉冲持续一个时隙ts。 需要两个数据波形来切换两种状态; 一个数据波形是另一个数据波形。 通常,选通波形脉冲可以是50伏。 在本发明中,电压降低波形(VRW)被添加到选通脉冲和数据波形。 这具有降低驱动器电路所需的电压的最大幅度的作用,同时将出现在显示元件处的合成电压保持在与不使用VRW相同的值。 随着电压要求的降低,以前用于相对低电压的阴极材料类型的显示器的驱动电路可用于切换近晶材料。

    Method and apparatus for multiplex addressing of a ferro-electric liquid
crystal display
    3.
    发明授权
    Method and apparatus for multiplex addressing of a ferro-electric liquid crystal display 失效
    铁电液晶显示器的多路寻址方法和装置

    公开(公告)号:US5398042A

    公开(公告)日:1995-03-14

    申请号:US488028

    申请日:1990-05-16

    IPC分类号: G02F1/133 G09G3/36

    摘要: A ferro-electric liquid crystal display is multiplex addressed by strobe waveform applied in sequence to each electrode in one set of electrodes coincidently with data waveforms applied to a second set of electrodes. Liquid crystal material in the display is switched by a d.c. pulse of appropriate polarity, amplitude and time. The strobe waveforms have first and second pulse pairs, each pulse pair comprising two pulses of different amplitude and the same or different sign. The pulse pairs are similar but of opposite sign. Data waveforms are rectangular waveforms of opposite sign. The amplitude and ratio of leading pulse to trailing pulse in each strobe pulse pair are adjusted to obtain the desired switching and contrast. Compensation for temperature changes is arranged by measuring the temperature of the liquid crystal material and using the value obtained to adjust the amplitude value of the leading pulse in each strobe pulse pair.

    摘要翻译: PCT No.PCT / GB88 / 01004 Sec。 371日期:1990年5月16日 102(e)日期1990年5月16日PCT提交1988年11月18日PCT公布。 第WO89 / 05025号公报 日期:1989年6月1日。一种铁电液晶显示器通过与一组电极中的每个电极顺序地施加到与第二组电极的数据波形重合的选通波形进行多路复用。 显示器中的液晶材料通过直流电 脉冲具有适当的极性,振幅和时间。 选通波形具有第一和第二脉冲对,每个脉冲对包括不同振幅和相同或不同符号的两个脉冲。 脉冲对是相似但相反的符号。 数据波形是相反符号的矩形波形。 调整每个选通脉冲对中的前导脉冲与后沿脉冲的幅度和比率,以获得所需的切换和对比度。 通过测量液晶材料的温度并使用获得的值来调整每个选通脉冲对中的引导脉冲的振幅值来进行温度变化的补偿。

    Method and apparatus for multiplex addressing of a ferro-electric liquid
crystal display
    4.
    发明授权
    Method and apparatus for multiplex addressing of a ferro-electric liquid crystal display 失效
    铁电液晶显示器的多路寻址方法和装置

    公开(公告)号:US5497173A

    公开(公告)日:1996-03-05

    申请号:US231917

    申请日:1994-04-25

    IPC分类号: G02F1/133 G09G3/36

    摘要: A ferro-electric liquid crystal display is multiplex addressed by blanking and strobe waveforms applied in sequence to each electrode in one set of electrodes coincidentally with data waveforms applied to a second set of electrodes. Liquid crystal material in the display is switched by a d.c. pulse of appropriate polarity, amplitude and time. The strobe waveforms have a pulse pair comprising two pulses of different amplitude and the same or different sign. Data waveforms are rectangular waveforms of opposite sign. The amplitude and ratio of leading pulses to trailing pulses in each strobe pulse pair are adjusted to obtain the desired switching and contrast. Compensation for temperature changes is arranged by measuring the temperature of the liquid crystal material and using the value obtained to adjust the amplitude value of the leading pulse in each strobe pulse pair.

    摘要翻译: 铁电液晶显示器通过对一组电极中的每个电极顺序地施加到与施加到第二组电极的数据波形重合的消隐和选通波形进行复用寻址。 显示器中的液晶材料通过直流电 脉冲具有适当的极性,振幅和时间。 选通波形具有包括两个不同幅度和相同或不同符号的脉冲的脉冲对。 数据波形是相反符号的矩形波形。 调整每个选通脉冲对中的前导脉冲与后沿脉冲的幅度和比,以获得所需的切换和对比度。 通过测量液晶材料的温度并使用获得的值来调整每个选通脉冲对中的引导脉冲的振幅值来进行温度变化的补偿。

    Multiplex addressing of ferroelectric liquid crystal displays
    5.
    发明授权
    Multiplex addressing of ferroelectric liquid crystal displays 失效
    铁电液晶显示器的多路寻址

    公开(公告)号:US06127996A

    公开(公告)日:2000-10-03

    申请号:US894507

    申请日:1997-09-17

    IPC分类号: G02F1/133 G09G3/36

    摘要: A ferroelectric liquid crystal display comprises a layer of ferroelectric liquid crystal material contained between two cell walls, surface treated to align the material in a tilted layer. The walls carry eg row and column electrodes forming an x,y matrix of addressable elements or pixels. Multiplex addressing voltages are provided by driver circuits. An improved addressing is obtained by varying the addressing voltage applied during switching of a pixel to maximize torque applied on liquid crystal molecules. Addressing voltages are from two data waveforms and one strobe waveform; the data waveforms have more than two voltage levels, dc balance, and equivalent rms. values; the strobe waveform has two or more voltage levels (which may include a zero level). The strobe and data waveforms combine to provide a resultant voltage that form an addressing voltage at each pixel.

    摘要翻译: PCT No.PCT / GB96 / 03077 Sec。 371日期1997年9月17日 102(e)日期1997年9月17日PCT 1996年12月12日PCT PCT。 公开号WO97 / 23863 日期1997年7月3日铁电液晶显示器包括包含在两个电池壁之间的铁电液晶材料层,经表面处理以将材料对准倾斜层。 墙壁携带例如形成可寻址元件或像素的x,y矩阵的行和列电极。 多路寻址电压由驱动电路提供。 通过改变在像素切换期间施加的寻址电压以最大化施加在液晶分子上的扭矩来获得改进的寻址。 寻址电压来自两个数据波形和一个选通波形; 数据波形具有两个以上的电压电平,直流平衡和等效有效值。 价值观 选通波形具有两个或更多个电压电平(其可以包括零电平)。 选通脉冲和数据波形相结合,提供在每个像素处形成寻址电压的合成电压。

    Ferroelectric liquid crystal display device with a particular angle
between the polarizer optical axes and the molecular director
    6.
    发明授权
    Ferroelectric liquid crystal display device with a particular angle between the polarizer optical axes and the molecular director 失效
    铁电液晶显示装置在偏光镜光轴和分子导向器之间具有特定的角度

    公开(公告)号:US5638143A

    公开(公告)日:1997-06-10

    申请号:US244935

    申请日:1994-06-15

    CPC分类号: G02F1/141 G02F2001/133531

    摘要: The invention provides a surface, or electric field, stabilised ferroelectric liquid crystal (SSFLC) device with an improved contrast ratio between its two switched states. The device comprises a liquid crystal cell formed by a thin layer (7), typically 1 to 5 .mu.m thick, of a smectic liquid crystal material, eg a smectic c, held between two glass walls (2, 3) coated on their inner faces with electrodes (5, 6). Polarizers (8, 9) are arranged either side the walls (2, 3). The device is switched between two bistable states by application of unidirectional voltage pulses, with or without the simultaneous application of ac bias voltages. To obtain optimum contrast ratio CR, the optical axis of the polarisers are rotated away from a crossed, or othogonal position. eg by +/-20.degree., and the cell rotated between the polarisers (8, 9); the precise optimum rotation depends upon material, and ac bias voltage.

    摘要翻译: PCT No.PCT / GB92 / 02368 Sec。 371日期:1994年6月15日 102(e)日期1994年6月15日PCT提交1992年12月21日PCT公布。 第WO93 / 13450号公报 日期1993年7月8日本发明提供了一种表面或电场稳定的铁电液晶(SSFLC)器件,其具有改善其两个切换状态之间的对比度比。 该装置包括由薄膜(7)形成的液晶单元,薄层(7)通常为1至5微米厚的保护在其内部涂覆的两个玻璃壁(2,3)之间的近晶体液晶材料,例如近晶体c 面与电极(5,6)。 偏振器(8,9)布置在墙壁(2,3)的两侧。 该器件通过施加单向电压脉冲在两个双稳态之间切换,具有或不同时施加ac偏置电压。 为了获得最佳对比度CR,偏振器的光轴从交叉或正交位置旋转。 例如+/- 20°,并且在圆偏振器(8,9)之间旋转的单元; 精确的最佳旋转取决于材料和交流偏置电压。