大视场双缝载频散斑干涉成像检测系统  

Double-slit based carrier frequency speckle interferometric system with large viewing field

作　　者：朱猛[1] 李翔宇[1] 龙宁波[1] 黄战华[1] 

机构地区：[1]天津大学精密仪器与光电子工程学院光电信息技术教育部重点实验室,天津300072

出　　处：《光学精密工程》2014年第1期13-17,共5页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.61275009);国家科技支撑计划资助项目(No.2007BA000013);高等学校博士学科点专项基金资助项目(No.20110032120059)

摘　　要：针对大面积的动态检测对大视场角散斑干涉技术的需求,研究了一种基于4f成像的大视场载频散斑干涉系统。该成像系统由前置广角镜头和4f成像系统组成;利用双缝干涉产生稳定的载频,在其中一个狭缝上加入不同楔角的光楔来控制剪切量的大小。分析了4f系统的焦距与双缝的间距和载频值之间的关系;采用散斑场自相关标定了4f系统中散斑统计的平均尺寸。分析证明:采用孔距为2mm的双缝配合80mm焦距的4f系统可以实现2π/3的稳定载频。分别采用12mm和6mm的标准成像镜头测量了动态形变的橡胶板,实现了40°和65°视场角的散斑干涉检测系统。实验结果证明该系统能实现大视场测量,载频与剪切量调节相互分离,提高了散斑检测系统的效率。For the requirements of a large area dynamic detection for the speckle interferometry with a large viewing filed, a carrier frequency speckle interferometric system based on 4f imaging is proposed. The imaging system includes a wide-angle lens and the 4f imaging lenses. The carrier frequency is introduced by a double-slit aperture and a prism is attached to generate an adjustable shearing image. The relation among the distance of slits, imaging length and the carrier frequency is analyzed. The statistical averaging speckle size in the 4f imaging system is also calibrated by the self correlation of speckle field. The analysis results show that the 4f imaging system combined with a double-slit in a seperation of 1 mm and a 0.5~ prism can produce 27r/3 carrier frequency in the 80 mm focus length. The 16 mm and 6 mm wide-angle lenses combined with the 4f imaging system are used to measure a rubber sheet and to demonstrate the proposed method. The experimental results show that this system can enlarge the viewing field and complete a speckle interferometric system with view angles of 40°and 65°. It concludes that the proposed system can adjust the carrier frequency and shear distance separately and can extend the dynamic detection area in a high efficiency.

关 键 词：散斑干涉 剪切干涉 成像系统 空间载频 视场角 

分 类 号：O436.1[机械工程—光学工程]