College of Optical Sciences, University of Arizona Tucson, Arizona 85721, USA.
Opt Lett. 2010 Feb 1;35(3):336-8. doi: 10.1364/OL.35.000336.
We demonstrate an innovative variable-focus flat liquid-crystal diffractive lens (LCDL) with 95% diffraction efficiency and millisecond switching times using a +/-2.4 V ac input. This lens is based on the electrical modulation of a 3 mum layer of nematic liquid-crystal sandwiched between a Fresnel zone electrode structure and a reference substrate. Each zone is divided into 12 subzones to digitize the phase profiles and define the phase wrapping points. The focusing power can rapidly be switched by electrically changing the number of subzones and re-establishing the wrapping points. Potential applications include zooms with no moving parts and autofocus lenses for compact imaging devices.
我们展示了一种具有 95%衍射效率和毫秒级开关时间的创新型可变焦平面液晶衍射透镜 (LCDL)，其采用 +/-2.4 V ac 输入。该透镜基于在菲涅尔区电极结构和参考基底之间夹有 3 µm 厚向列液晶层的电调制。每个区被分成 12 个子区，以对相位分布进行数字化并定义相位缠绕点。通过电改变子区的数量并重新建立缠绕点，可以快速切换聚焦力。潜在应用包括具有无移动部件的变焦和用于紧凑型成像设备的自动对焦镜头。
