Optical System Design And Precision Analysis Of A Scanning Testing Equipmeng

With wide applications of laser beam scanning technology in the various fields such as in the scientific research, industrial production, and especially military affairs, it is very important to develop laser scanning testing equipment with high testing precision and general purpose. In response to this demand, the paper completed design the optical system of laser scanning testing equipment and analyze the precision of overall equipment.Based on the diffraction theory and the designed methods of the diffractive optical elements in the optical imaging system and the characteristics of optical components, the refractive-diffractive optical system was designed. The system has many advantages which include high imaging quality (maximum distortion≤2%, MTF≥0.6), large field of view (60°), wide spectrum (800-1064nm), large back focal length (30mm), high resolving power (42lp/mm), and the results meet the laser scanning testing equipment requirements. In addition, the relevant design methods of refractive-diffractive optical system was summarized and analyzed.The Methods were studied that the zoom lens was used in the scanning testing equipment. The distortion correction's method of the zoom lens was completed, and the result of the experiments was that the relative distortion of the image dropped to 12.5% contrast to the past. This showed that the distortion correction's method can improve the detection precision of the scanning testing equipment effectively.The method of increasing measuring precision was given about the laser scanning testing equipment. The problem was analyzed about the axial of the laser scanning testing equipment in the measurement conditions, when using the optical system and the zoom optical system respectively, analyzed the best measuring method and the method of measuring the zoom lens's focal length.The precision analysis of the scanning testing equipment was completed. Deduced measurement equation and error propagation formula was given. After completed aberration correction, measurement of focal length, and axis angle correction on scanning testing equipment, using these errors as the corresponding error limits, analyzed the precision of the scanning testing equipment when using the fixed-focus optical system and the zoom optical system. The results showed that the precision of the scanning angle was less than 0.01 rad.