360°高阶非球面反射式全景镜头设计

为了简化系统配置、提高图像采集及处理效率,实现单一光学系统环视高清全景成像,依据折反射式光学系统的工作原理,设计了高阶非球面反射式360°全景镜头,并对光学结构和系统像质进行优化设计。该相机采用高阶非球面反射镜压缩视场角,将垂直光轴方向俯仰角从-55°到20°的环视目标光引入到系统,接着,在后续光路中利用玻璃透镜组对目标光进行接收,并使其聚焦于相机靶面,获得物体的环形全景图像。通过对系统像质的优化,得到高清的360°环视全景图像,并对光学系统的主要性能指标进行了分析。所设计的360°全景镜头采用1片高阶非球面反射镜和10片玻璃球面镜组成,系统的焦距为0.4mm,光圈数为2.2,俯仰角达到75°,像方全视场在150lp/mm处的光学传递函数值均大于0.3。该360°全景镜头采用单一光学系统成像,解决了传统拼接式全景镜头图像采集与图像处理效率低的问题,同时通过简化系统结构,使该产品符合成本低、可量产的要求。

Design of 360° high-order aspheric reflective panoramic lens

In order to simplify system configuration, improve the efficiency of image collection and processing, and achieve round high-definition panoramic optical imaging using a single optical system according to the working principle of a catadioptric optical system, we designed a 360° panoramic lens with high-order aspheric reflection and optimized its optical structure and image quality. This camera utilizes a high-order aspheric reflector to compress the field of view. Round target light with an elevation angle ranging from -55° to 20° was introduced into the system and a glass lens assembly was used to receive this light in a subsequent light path. The light was focused on the target surface of the camera that facilitated the acquisition of annular panoramic images of the object. By optimizing the image quality of the system, we obtained high-definition 360° round-looking panoramic images and subsequently analyzed the primary performance indexes of the optical system. The 360° panoramic lens consists of a high-order aspheric reflector and 10 glass spherical lenses. It had a focal length of 0.4 mm, an f-number of 2.2, and a pitch angle of 75°. The optical transfer function values of the full field of view are all greater than 0.3 at a resolution of 150 lp/mm. This proposed design is applicable to single optical system imaging and addresses several significant technical challenges in traditional spliced panoramic lenses including inefficient image collection and processing. In addition, the simple design is inexpensive and can, therefore, facilitate a high-volume production.