Design Of High Definition Endoscope Optical System

Laparoscopy is an endoscope for observing,diagnosing,and treating intraperitoneal lesions.At present,most of the domestic research and production of laparoscopy is suitable for adult patients.With the improvement of endoscopy technology and medical level,the thin diameter laparoscopy will gradually be applied to children's surgery.In view of this,the endoscope designed by our project is an optical system that can be applied to children's high-definition and thin diameter laparoscopy.The system combines the optical system of the rigid endoscope with the optical system of the electronic laparoscope to achieve the targets of fine caliber,high resolution and so on.Through the analysis of the basic principle and structure composition of laparoscopic,select the appropriate initial structure of the thin diameter HD laparoscope,based on the requirements to calculate the design parameters of small diameter laparoscopic,using ZEMAX software to simulate the design,a wavelength at 0.486?m~ for 0.656?m,the pupil diameter is 0.1mm,the viewing angle is 100 degrees,the focal length of the front objective lens group is 0.895 mm of the high definition and fine diameter laparoscopic optical system,the system is composed of a front lens group,image rotation system,after the lens,the image transferring system is composed of three groups of rod lens and the field lens.The optimal design results show that the total length of the thin-diameter laparoscopic optical system is 247mm;At the spatial cut-off frequency is 143lp/mm,the optical transfer function(MTF)is greater than 0.3,and is close to the diffraction limit,which satisfies the resolution requirement.The maximum diameter of the system is not greater than 3mm,according to the characteristics of the thin diameter laparoscope,it meets the requirements of use.By analysis the results of design object distance,meet the requirements of large depth of field;analysis the tolerance and meet the processing requirements.