Polarimetry technique is very important for analyzing the THz radiations (divergence, spatial or frequency modes, and profiles). The key instrument in polarimetry is polarization modulator which identifies and measures polarized signal.

Plano-plano plates, made of birefringent material, are used for modifying polarization state of radiation. A waveplate works by shifting the phase between two perpendicular polarization components of the wave. The most common types of waveplates are a half-wave plate (λ/2 plate) and a quarter-wave plate (λ/4 plate). λ/2 plate gives phase delay π and λ/4 plate — π/2. A half-wave plate changes the polarization direction of linear polarized light. A quarter-wave plate changes linearly polarized light to circular and vice versa. Waveplate will not change the polarization of linearly polarized beam if the polarization direction is along one of waveplate axes.

Operating principle of Half-wave plate

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偏振测量技术对于分析THZ波（发散角，空间和频率分布）是非常重要的。在偏振测量仪中最关键的设备是偏振调制器，用来鉴定和测量偏振信号。

双折射材料制成的平行平板可用来改变电磁波的偏振态。波片可产生两个正交方向上的偏振态相位的漂移。最常用的波片是半波片和1/4波片。1/2的波片可产生π的相位延迟，1/4波片可产生π/2的相位延迟。半波片可改变线偏振光的偏振方向。1/4波片将线偏振光改成圆偏光，反之亦然。如果偏振方向沿着波片的光轴，则波片不会改变偏振态。

半波片和1/4波片的工作原理如下：

Tydex提供的THZ波片是单波长波片，可以提供定制规格。

矩形尺寸、圆形尺寸、配套可调谐旋转安装座子。

产品联系：伽太科技，sales@gamtic.com，135 8596 2889.

主要参数：  

单色THz波片的标准品规格如下：