The acronym POLICRYPS indicates a nano/micro composite structure made of films of well aligned nematic liquid crystal (NLC) alternated to slices of almost pure polymer. Structures are fabricated by curing a homogeneous mixture of mesogenic material, monomer and a curing agent with UV radiation, under suitable physical and geometrical conditions. In particular, geometrical conditions determine (in the range 0.2 ÷ 15 μ m) the spatial periodicity of the realized sample, which can be utilized for transmitting, diffracting or reflecting an impinging light beam, with negligible scattering losses. The spatial modulation of the refractive index (from polymer to NLC) can be switched ON and OFF both by applying an electric field of few V/μ m or, in some cases, by irradiating the sample with a light beam of suitable wavelength. This electrical/optical tuneability is responsible for a series of distinctive characteristics of the optical effects produced by the structure, and determines the range of possible applications. In fact, in different geometries, the POLICRYPS can be exploited as a switchable holographic grating, a switchable optical phase modulator, a switchable beam splitter, a tuneable Bragg filter or it can be exploited as an electro-optical edge filter in an optical interrogation system.

首字母缩写词POLICRYPS表示由排列良好的向列液晶（NLC）薄膜与几乎纯净的聚合物片交替制成的纳米/微复合结构。结构是通过在适当的物理和几何条件下，将介晶材料，单体和固化剂的均匀混合物与UV辐射固化而成的。尤其是，几何条件决定了所实现样品的空间周期性（在0.2÷15μm范围内），该空间周期性可用于透射，衍射或反射入射光束，而散射损失可忽略不计。折射率的空间调制（从聚合物到NLC）可以通过施加几个V /μm的电场，或者在某些情况下，通过用适当波长的光束照射样品来打开和关闭。这种电/光可调节性负责结构产生的光学效果的一系列独特特征，并确定了可能的应用范围。实际上，在不同的几何形状中，POLICRYPS可以用作可切换的全息光栅，可切换的光学相位调制器，可切换的分束器，可调的布拉格滤波器，也可以用作光学询问系统中的电光边缘滤波器。