Liquid crystal light attenuation device

Abstract

The invention provides a liquid crystal light attenuation device. The light attenuation device comprises a first substrate and a second substrate which are arranged face to face, a liquid crystal layer sealed between the first substrate and the second substrate, a first reflecting layer arranged on one side of the first substrate toward the liquid crystal layer, a second reflecting layer arrangedon one side of the second substrate toward the liquid crystal layer, first common electrodes and first control electrodes which are arranged on one side of the first reflecting layer toward the liquidcrystal layer and second common electrodes and second control electrodes which are arranged on one side of the second reflecting layer toward the liquid crystal layer, wherein the liquid crystal layer has the property that under an electric field, the isotropic refractivity can be converted to the anisotropic refractivity, the first common electrodes and first control electrodes are arranged alternately, the second common electrodes and second control electrodes are arranged alternately, the second control electrodes are opposite to the first control electrodes, and the second common electrodes are opposite to the first common electrodes. The liquid crystal light attenuation device can increase the response speed.

Description

technical field [0001] The invention relates to the technical field of liquid crystals, in particular to a liquid crystal light attenuation device. Background technique [0002] In recent years, the rapid development of liquid crystal technology has promoted its wider application in the fields of flat panel display, light attenuation device and wavelength variable filter. At present, the most commonly used liquid crystal light attenuation device adopts Twisted Nematic (TN) type liquid crystal, but the response speed of TN type liquid crystal is very slow, usually tens of milliseconds, thus limiting the application of liquid crystal light attenuation device . [0003] In the prior art, the following two solutions are adopted to improve the response speed of the liquid crystal light attenuation device: [0004] (1) Reducing the thickness of the liquid crystal cell of the TN type liquid crystal light attenuation device can make the response speed of the light attenuation devi...

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Problems solved by technology

On the one hand, since the response time of the TN-type liquid crystal cell is proportional to the square of the cell thickness, although reducing the cell thickness of the liquid crystal cell can speed up the response speed of the liquid crystal light attenuation device, in general, the TN-type liquid crystal cell is suitable for modulation in the visible light band , if the modulation wavelength is in the mid-to-far infrared band, the response time will increase dozens of times, and the thickness of the liquid crystal cell cannot be reduced without limit. This solution has limited improvement in response speed, and the reduction in thickness will bring On the other hand, the ferroelectric liquid crystal light attenuation device currently has the following problems: (1) The arrangement and orientation of the ferroelectric liquid crystal needs to be coated with an alignment layer material on the surface of the glass substrate with electrode patterns , the arrangement and orientation of ferroelectric liquid crystal molecules is controlled by rubbing orientation, and due to the molecular characteristics of ferroelectric liquid crystal itself, it is very difficult to achieve uniform orientation; (2) the thickness of the liquid crystal cell of surface-stabilized ferroelectric liquid crystal is very small (usually 2um) , it is difficult to be suitable for the application of long-wavelength light attenuation devices; (3) ferroelectric liquid crystals are prone to alignment defects when they are impacted by external forces, and this defect is irreversible; (4) when the ferroelectric liquid crystal is applied to another angle, due to The role of anchoring energy, the transition layer liquid crystal close to the surface of the alignment layer is not easy to change direction, which affects the contrast of the light attenuation device

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