摘要
针对传统变焦腹腔镜调焦结构所需空间大、调焦精度难以保证等问题,提出了一种以液体透镜为核心元件参与变焦的腹腔镜光学系统,利用液体透镜代替机械变焦结构,实现了变焦功能。推导了液体透镜电压与焦距的关系方程,结合COMSOL软件设计并仿真了满足所需焦距范围的双液体透镜。用ZEMAX软件设计优化了腹腔镜液体透镜变焦光学系统,通过控制电压即可实现焦距5~15 mm范围内同一像面高清晰成像。在焦距15 mm时,全视场点列图均方根(RMS)半径为6.694μm,在焦距5 mm时,全视场点列图RMS半径为4.596μm,均小于7.4μm的像元尺寸。系统调制传递函数(MTF)在68 lp/mm处均大于0.5,4个组态(焦距分别为5、7.2、10.4、15 mm)畸变分别为7.047%、1.961%、0.732%、0.295%,满足腹腔镜对光学系统畸变的要求。
Objective At present,the medical endoscope mainly uses the fixed focus optical system and relies on image processing and other means to scale the image.Due to the large space occupied by traditional mechanical zoom optical system as well as its difficulty in zooming,it has not been applied to medical endoscopes.Based on the concept of bionics,the liquid lens is a small,integrated and selfzooming lens.The electrowetting liquid lens is applied to the design of medical endoscope.Zooming can be realized by adjusting the voltage and the image quality can be guaranteed.Some scholars at home and abroad have studied the optical system of endoscope containing liquid lens,but there are many problems in the existing research contents,such as large distortion and difficulty to guarantee the image quality.In this paper,based on the traditional zoom optical design of medical laparoscope,an autonomous zoom optical system with small distortion and simple structure is designed,which is suitable for medical endoscope.Methods The electrowetting liquid lens,which depends on voltage to adjust the curvature of the interface,is selected as the core zoom element.The basic parameters of the optical system are determined according to the main technical indexes,the mechanical zoom optical system is designed by optimizing the initial structure of traditional zoom optics,and the initial optical structure of a zoom laparoscope is obtained.The parameters of liquid lens are determined according to the changing range of focal length and the aperture of optical system,and then the liquid lens is designed and simulated by COMSOL.The simulation diagram of liquid lens interface is given when the voltage is 0,35 and 60 V.The corresponding relationship between voltage variation and liquid level variation is simulated.When the voltage reaches 60 V,the contact angle of the electrowetting liquid lens reaches saturation,and the liquid lens interface no longer changes.MATLAB software is used to simulate the corresponding relationship between voltage and fo
作者
董健
王春艳
孙昊
刘欢
滕云杰
Dong Jian;Wang Chunyan;Sun Hao;Liu Huan;Teng Yunjie(School of Optoelectronic Engineering,Changchun University of Science and Technology,Changchun 130022,Jilin,China)
出处
《中国激光》
EI
CAS
CSCD
北大核心
2023年第21期173-181,共9页
Chinese Journal of Lasers
基金
吉林省教育厅科学技术研究项目(JJKH20220755KJ)
吉林省科技发展计划(20220201074GX)。
