【作者】 牛爽；

【导师】 杨国光； 白剑；

【作者基本信息】 浙江大学 ， 测试计量技术及仪器， 2010， 博士

【摘要】 全景环带透镜是一种具有超大视场的透镜。它通过一个特殊的同时具有折反折表面的光学结构,把360°视场投影在一个平面上,形成一个圆环像。这种结构因为体积小,能实现全景实时监控,使用方便,正在越来越多地被应用于军事、医疗、监控等领域。由于全景环带透镜的视场很大,现存的全景环带光学系统焦距均较小(约1mm)。而对于某些领域,短焦距的全景环带光学系统远远不能满足要求。针对这种需求,本文对焦距约为10mm的超半球全景环带光学系统的光学/机械设计、加工和应用进行了全面而系统的研究。本文首先通过理论分析和设计实践,阐述了消色差结构在全景环带光学系统设计中的重要作用。提出使用全新的胶合式全景透镜代替普通全景透镜。设计并制造了焦距10.2mm,带有胶合式全景透镜的全景环带光学系统。为了进一步简化该全景光学系统的结构,减少透镜片数,提高光线透过率,本文提出在全景环带光学系统中引入衍射表面。设计实例表明,衍射表面对于全景光学系统的像差校正有着非常好的帮助,可以大大简化全景环带光学系统的结构。为了解决衍射表面在宽波段光谱效率不集中,成多个像的问题,本文又提出使用多层衍射结构代替普通的单片衍射透镜。通过理论分析计算,使用双层衍射结构的透镜,可以使可见光光谱范围内的光线在+1级的衍射效率均大于94%,并有效抑制其它级次的衍射效率,进一步简化光学系统。设计并加工制作了一套带有双层二元面的全景环带成像光学系统,对系统测试结果进行了详尽的分析,并对下一步工作提出了指导性建议。最后,本文为全景环带透镜的应用提出了一种全新的,同时使用两片全景环带透镜和一个CCD探测器实现立体成像的光学系统,并对该系统的原理进行了阐述。本文的主要创新有：对全景环带光学系统的光学特性进行了全面的分析,提出了带有普适性的全景环带光学系统的设计方法。设计并加工出一种新的全景环带成像光学系统,其系统焦距约为现有全景光学系统10倍。提出了使用胶合式全景环带透镜代替传统单片全景透镜；在后继转像透镜组中引入多层衍射表面等方法,对该光学系统进行了改进和完善,使得系统参数保持不变的情况下,系统结构得到很大简化。本文还针对各种方案分别进行了工程样机试制。同时,本文提出了全景环带光学系统在立体成像方面的全新应用。更多还原

【Abstract】 Panoramic Annular Lens (PAL) is a special lens with super large Field of View (FOV). It projects a cylindrically panoramic view of 360°around the optical axis to an annular area on a plane. Because of its miniature and convenience, PAL is applied to many areas, such as military, medical and monitoring.PAL has a super large FOV. Therefore, nearly all existing Panoramic Annular optical systems have short focus. However, PAL with short focus cannot satisfy the need of viewing objects far away. In order to solve this problem, we worked over design, manufacture and application of PAL system with long focus comprehensively.In this dissertation, we firstly research into the imaging principle of PAL According to the analysis, we find the importancy of eliminating chromatic aberration, and we propose a new cemented PAL to replace tradional one-piece PAL. Advantage of new cemented PAL is demonstrated by analysis and calculation. A panoramic annular optical system with new cemented PAL is designed and produced.Secondly, we bring in diffractive structure for the sake of simplifying panoramic annular optical system with long focus. Examples indicate that the diffractive structure helps to reduce the aberration of panoramic annular optical system effectively. And the system can be much more simplified by this structure.However, for a single-piece diffractive suface, it is difficult to concentrated light in a wide spectrum to a certain order. To solve this problem, a new Multi-Diffractive Optical Element (MDOE) is proposed to replace ordinary single-piece Diffractive Optical Element (DOE). It is demonstrated by calculation that, this new structure can concentrate over 99.3% light in visible spectrum into +1 order. Prototype of an optical system with a MDOE structure is designed and manufactured. Testing results an analyzed in detail. Suggestions for the next work are proposed.Finally, a new application of panoramic annular stereo optical system is proposed. This system consists of two pieces of PAL and a CCD detector. Principle of this new system is described.Innovation of the dissertation:optical properties of panoramic annular optial system are analysed thoroughly. A universal method of designing panoramic annular optical system is propoed. A new panoramic annular optical system is designed and manufactured. Focal length of this system is 10 times of the existing systems. New cemented PAL is used to replace traditional one-piece PAL. MDOE is brought in to correct the chromatic aberration and to simplify the optical system effectively. Plenty of manufacture and design experience are described in the dissertation. A new panoramic annular stereo optical system is also proposed in this dissertation as an application of PAL.更多还原