Kuroda Yuma, Harada Yuki, Emoto Akira, Matsukawa Mami, Koyama Daisuke
Appl Opt. 2024 Mar 20;63(9):2256-2262. doi: 10.1364/AO.515888.
Compound lens systems with mechanical actuators are used to focus objects at near to far distances. The focal length of ultrasound varifocal liquid crystal (LC) lenses can be controlled by modulating the refractive index spatial distribution of the medium through the acoustic radiation force, resulting in thin and fast-response varifocal lenses. The frequency characteristics of such a lens are evaluated in this paper, and several axisymmetric resonant vibration modes over 20 kHz are observed. The effective lens aperture decreased with the wavelength of the resonant flexural vibration generated on the lens, meaning that this parameter can be controlled with the driving frequency.
带有机械致动器的复合透镜系统用于将物体从近距聚焦到远距。超声变焦距液晶（LC）透镜的焦距可通过声辐射力调制介质的折射率空间分布来控制，从而得到薄且响应快的变焦距透镜。本文评估了这种透镜的频率特性，并观察到了20kHz以上的几种轴对称共振振动模式。有效透镜孔径随透镜上产生的共振弯曲振动波长减小，这意味着该参数可通过驱动频率来控制。
