电子内窥镜光学系统设计

内窥镜观察范围大，并且观察系统多与手术器械相配合，具有广角长工作距的特点，因此物镜采用非对称反远距结构。设计的光学系统采用尺寸为3.30mm×2.95mm CCD接收成像，像元大小为3.275μm，实现了短焦距（1.7mm）、细径化（Φ=5.5mm）、大视场（100°）、长工作距（50mm）的光学特性。由于该系统为大视场光学系统，会有较大畸变，针对反远距物镜分析了其结构特点和像差特性，通过计算得出系统各个参数，并合理的引用非球面，达到了提高系统成像质量并且降低系统畸变的目的，利用ZEMAX光学设计软件给出了设计实例，并已经应用到实际生产中。

Optical System Design of Electronic Endoscope

The objective in this paper is an electronic endoscope,to meet the requestment of wide range for endoscopic obser-vation and observation system more compatible with surgical instruments, thus it is characterized by a wide-angle and long working distance, so the objective lens adopt structure of asymmetrical inverse distance. The optical system adopts 3.30 × 2.95mm CCD as receiver. The pixel size is 3.275μm,which realizes the optical properties of short focal length(1.7mm),small diameter,a large field of view(100 degrees)and long working distance(50mm). Since the system is a large field optics sys-tem, there will be a larger distortion. For the inverted telephoto objective in this paper, the structure characteristics and the optical aberration are analyzed,and the example is presented by ZEMAX software,through the calculation,system parame-ters are obtained,Adopting the aspheric surface reasonably can enhance the imaging quality of system,reduce the system dis-tortion,and the example has been applied to actual production.