Liquid crystal spatial light modulator for edge detection employing
diffusion in the photoconductive layer to enlarge image
    1.
    发明授权
    Liquid crystal spatial light modulator for edge detection employing diffusion in the photoconductive layer to enlarge image 失效
    用于边缘检测的液晶空间光调制器,其利用光电导层中的扩散来放大图像

    公开(公告)号:US5420709A

    公开(公告)日:1995-05-30

    申请号:US905280

    申请日:1992-06-26

    CPC分类号: G06K9/58 G02F1/135 G02F1/141

    摘要: An edge image extraction light modulator forms an edge portion image corresponding to a boundary between two optically equalized portions of a liquid crystal layer. Each portion has a different bistable state and an edge portion optically distinct from the two optically equalized portions. An optical image is written onto the light valve while applying a voltage between two transparent electrode layers of the light valve to effect switching between a first stable optical axis and a second stable optical axis. The light valve is illuminated and the edge portion of the written image is read. A first and a second polarizer are in crossed-Nicols position so that the two optically equalized portions comprise a portion having the written image except for the edge portion thereof and a non-written portion. The edge portion is not optically equal to the two optically equal portions and can thus be detected. A method of driving the edge image extraction light modulator includes writing an optical image onto the light valve by irradiating a photoconductive layer with light. A first pulse voltage is applied to erase and reset the light valve, and a second pulse voltage is applied, having a polarity opposite that of the first pulse voltage, to generate carriers diffusing in the photoconductive film to impart an electric field to the liquid crystal layer and form an enlarged image of the optical image in the light valve. A third pulse voltage, having the same polarity as that of the first pulse voltage, erases a part of the enlarged image except for an edge portion thereof to form an edge enhanced image in the light valve.

    摘要翻译: 边缘图像提取光调制器形成与液晶层的两个光学均衡部分之间的边界对应的边缘部分图像。 每个部分具有不同的双稳态和与两个光学均衡部分光学不同的边缘部分。 在光阀的两个透明电极层之间施加电压以在第一稳定光轴和第二稳定光轴之间进行切换,将光学图像写入光阀。 点亮光阀,读取写入图像的边缘部分。 第一和第二偏振器处于十字尼科耳尔位置,使得两个光学均衡部分包括除了其边缘部分之外的具有写入图像的部分和非写入部分。 边缘部分不是光学上等于两个光学相等的部分,因此可以被检测。 驱动边缘图像提取光调制器的方法包括通过用光照射光电导层将光学图像写入光阀。 施加第一脉冲电压以擦除和复位光阀,施加具有与第一脉冲电压相反的极性的第二脉冲电压,以产生在光电导膜中扩散的载流子以向液晶施加电场 并在光阀中形成光学图像的放大图像。 具有与第一脉冲电压相同极性的第三脉冲电压擦除除了其边缘部分之外的放大图像的一部分,以在光阀中形成边缘增强图像。

    Ferroelectric liquid crystal spatial light modulator with two threshold
characteristics
    2.
    发明授权
    Ferroelectric liquid crystal spatial light modulator with two threshold characteristics 失效
    铁电液晶空间光调制器具有两个阈值特性

    公开(公告)号:US5623352A

    公开(公告)日:1997-04-22

    申请号:US93351

    申请日:1993-07-16

    IPC分类号: G02F1/133 G02F1/135 G02F3/00

    CPC分类号: G02F1/135

    摘要: By using a ferroelectric liquid crystal light valve having a hydrogenated amorphous silicon photoconductive layer, a spatial light modulator may be driven by a method comprising the sequential application of successive pulse voltages of selective amplitude, polarity and duration to cause the spatial light modulator to manifest a second threshold level suitable for application of the device in Boolean processing applications and Fourier image processing.

    摘要翻译: 通过使用具有氢化非晶硅光电导层的铁电液晶光阀,空间光调制器可以通过包括顺序施加选择性振幅,极性和持续时间的连续脉冲电压的方法来驱动,以使空间光调制器显示出 适用于布尔处理应用和傅立叶图像处理中的设备的第二阈值水平。

    Method for driving ferroelectric liquid crystal light valve of light
writing type
    3.
    发明授权
    Method for driving ferroelectric liquid crystal light valve of light writing type 失效
    轻型书写式电磁液晶灯的驱动方法

    公开(公告)号:US5221980A

    公开(公告)日:1993-06-22

    申请号:US755616

    申请日:1991-09-05

    IPC分类号: G02F1/133 G02F1/135 G09G3/36

    CPC分类号: G02F1/135

    摘要: The present invention is concerned with point/output characteristics of a light input image having density gradation using a light writing type light valve comprising a combination of a hydrogenated amorphous silicon photoconductor and a ferroelectric liquid crystal. More specifically, the invention relates to a method of expressing continuous gradation using a light writing type ferroelectric liquid crystal light valve that has been difficult to realize. The expression of continuous gradation is made possible by superposing a DC bias voltage of from 0.1 V to 10 V on a rectangular-wave voltage or a bipolar pulse voltage that has theretofore been used as a driving voltage in order to strongly couple together the spontaneous polarization of ferroelectric liquid crystal and the polarity of the DC voltage, and by eliminating the bistability exhibited by the ferroelectric liquid crystal while developing a monostable condition.

    Method of introducing slightly titlting homeotropic orientation into
liquid crystal, liquid crystal electro-optical device, and liquid
crystal light valve
    4.
    发明授权
    Method of introducing slightly titlting homeotropic orientation into liquid crystal, liquid crystal electro-optical device, and liquid crystal light valve 失效
    向液晶,液晶电光装置和液晶光阀引入轻微滴定的垂直取向的方法

    公开(公告)号:US5745205A

    公开(公告)日:1998-04-28

    申请号:US554681

    申请日:1995-11-07

    IPC分类号: G02F1/1337

    摘要: An object of the invention is to provide a method of introducing sightly tilting homeotropic orientation into a liquid crystal layer by oblique evaporation of inorganic material by one step, and a further object is to apply this method to provide a reliable liquid crystal electro-optical device or a liquid crystal light valve. FIG. 1 shows an example of the method to introduce the slightly tilting homeotropic orientation into the liquid crystal layer by the one step of the oblique evaporation of the inorganic material. The orientation film is formed by the one step oblique evaporation. An incident angle is set from 45.degree. to 70.degree. relative to a parallel direction of the substrate, and a film thickness is set to 20 nm through 500 nm measured during the film deposition by a film thickness gage disposed at a vertical distance equal between the evaporation source and the substrate. The orientation film is used in the liquid crystal electro-optical device or the liquid crystal light valve.

    摘要翻译: 本发明的目的是提供一种通过一步法将无机材料倾斜蒸发而将视力倾斜的垂直取向引入液晶层的方法,并且另一个目的是应用该方法来提供可靠的液晶电光装置 或液晶光阀。 图。 图1示出了通过无机材料的倾斜蒸发的一个步骤将稍微倾斜的垂直取向引入液晶层的方法的示例。 取向膜通过一步倾斜蒸发形成。 入射角相对于基板的平行方向为45度〜70度,膜成膜时的膜厚​​为20nm〜500nm,膜厚设定为 蒸发源和底物。 取向膜用于液晶电光装置或液晶光阀。