Wang Jia, Amani Alireza, Zhu Chengxi, Bai Jian
Appl Opt. 2021 Aug 1;60(22):6448-6455. doi: 10.1364/AO.432617.
A compact varifocal panoramic annular lens (PAL) system based on the four-component mechanical zoom method is proposed, which solves the problem that the traditional PAL system cannot zoom in to the region of interest. By moving the zoom group and the compensation group, our design achieves continuous zooming, in which the focal length changes from 3.8 to 6 mm. It can keep the position of the image surface unchanged while maintaining a compact structure. The system has a field of view (FoV) of 25°-100° in wide-angle mode and an FoV of 25°-65° in telephoto mode. The modulation transfer function of the wide-angle view is higher than 0.22 at 147 lp/mm. The -theta distortion is less than 3%, and the relative illuminance is higher than 0.9 in the zoom process. Compared with the zoom PAL system with multiple free-form aspheric surfaces, the proposed system uses multiple spherical lenses and only one -type asphere lens to achieve outstanding panoramic zoom imaging results. It is practical and straightforward, easy to manufacture, detect, and mass produce.
提出了一种基于四组件机械变焦方法的紧凑型变焦距全景环形透镜（PAL）系统，该系统解决了传统PAL系统无法变焦至感兴趣区域的问题。通过移动变焦组和补偿组，我们的设计实现了连续变焦，其中焦距从3.8毫米变化到6毫米。它可以在保持紧凑结构的同时，使像面位置不变。该系统在广角模式下的视场（FoV）为25°-100°，在长焦模式下的FoV为25°-65°。广角视图的调制传递函数在147 lp/mm时高于0.22。在变焦过程中，-θ畸变小于3%，相对照度高于0.9。与具有多个自由曲面非球面的变焦PAL系统相比，所提出的系统使用多个球面透镜和仅一个类型的非球面透镜，实现了出色的全景变焦成像效果。它实用且简单，易于制造、检测和批量生产。
