Li Lei, Wang Jin-Hui, Wang Qiong-Hua, Wu Shin-Tson
Opt Express. 2018 Oct 1;26(20):25839-25848. doi: 10.1364/OE.26.025839.
A conventional optofluidic lens usually has one liquid-liquid (L-L) interface, which can be deformed to achieve variable focal length. Such a single lens cannot be used alone to realize optical zooming because its back focal distance keeps changing. Here, we report a novel displaceable and focus-tunable electrowetting optofluidic lens. In comparison with the conventional optofluidic lens, our new lens has a different working principle and it can function as an optical zoom lens. The L-L interface can be displaced by a voltage. The object distance and image distance can be adjusted by shifting the L-L interface position to achieve the desired magnification, yet the lens can refocus the image by reshaping the L-L interface with another voltage. Under such condition, only one lens is adequate to realize the zooming functionality. To prove the concept, we fabricate an optofluidic lens whose largest displaceable distance is ~8.3 mm and the zooming ratio is ~1.31 ×. The proposed optofluidic lens greatly simplifies the zoom lens system. Widespread application of such an adaptive zoom lens is foreseeable.
传统的光流控透镜通常有一个液-液（L-L）界面，该界面可变形以实现可变焦距。这样的单透镜不能单独用于实现光学变焦，因为其后焦距不断变化。在此，我们报道了一种新型的可位移且焦距可调的电润湿光流控透镜。与传统的光流控透镜相比，我们的新型透镜具有不同的工作原理，并且它可以用作光学变焦透镜。L-L界面可通过电压进行位移。通过移动L-L界面位置可以调节物距和像距以实现所需的放大倍率，同时透镜可以通过用另一个电压重塑L-L界面来重新聚焦图像。在这种情况下，仅一个透镜就足以实现变焦功能。为了验证这一概念，我们制造了一个光流控透镜，其最大可位移距离约为8.3毫米，变焦比约为1.31倍。所提出的光流控透镜极大地简化了变焦透镜系统。可以预见这种自适应变焦透镜将得到广泛应用。
