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本论文主要介绍了一种用来空间上调节光的传播方向跟偏振态的光学薄膜结构.这种结构包含多层图案化的双折射薄膜,每一层都是由液晶聚合物(LCP)构成,这些聚合物的光轴方向由一层图案化的光配向层控制而变化.这种光调制器有两层功能层,第一层的设计是图案化的偏振光栅,光栅向量方向可以空间上变化,已达到空间调制光的传播方向的作用,第二层是一层图案化的光延迟膜,可以调节出射光的偏振态.这种多薄结构的厚度小于1 μm,有助于提供高分辨率的光波前结构.它还可以当做光掩模,用来产生多畴配向结构的光配向层,应用到现代液晶显示器的制造中.为了验证这种结构的实用性,我们成功地制作了这种多层膜结构,并用它在单次曝光的条件下制作了一个两域光配向结构的液晶盒.这种光学薄膜结构在调制光的传播方向跟偏振态方面有着独特的功能,可以广泛应用于微型制造、三维成像、光通信、光计算、光开关等等领域.

In this article,an advanced optical thin film structure for spatially modulating light propagation directions and polarizations is introduced.The optical structure is composed of multi-layer patterned birefringence thin films,of which each thin film is formed by a liquid crystal (LC) polymer layer with spatially varying optical axes controlled by a patterned photoalignment layer.The optical modulator has two functional layers,where the first layer is designed as patterned polarization grating with spatially varying grating vectors to spatially steer light propagation directions,and the second layer is a patterned retardation film for controlling the output light polarizations.The overall thickness of the multi-layer films,excluding thesubstrate,can be less than 1μm,which offers the flexibility to generate high resolution light wavefront structure.As a result,the optical thin film can be ideally working as a photomask for exposure on a LC photoalignment layer to generate multi-domain alignment structures,which can be applied for the manufacturing and designing of modern liquid crystal display.To verify the effectiveness of the proposed photomask,a periodic two domain thin film structure has been designed and fabricated and a liquid crystal cell with two-domain alignment structure has been successfully fabricated in a single exposure with the photomask.The proposed optical thin film has unique functions in modulating light propagating directions and polarizations,which has great potential to find applications on micro-fabrication,3D display,optical communication,optical computing and optical switching,etc.