显微测量中倾斜会导致显微图像的变形。本文利用多光束改进传统的激光三角法,提出一种多光斑激光三角法检测光学成像系统倾斜角度和方向。首先利用双楔镜分离扩束后的激光光束,形成近似平行的四束光束;然后将四束光束同时投射到平面镜上,反射后利用CCD接收到四个光斑。由于四个光斑间距的变化只与成像系统倾斜角度有关,对成像系统前后的平移不敏感,因此避免了平移带来的影响。通过计算四个光斑间距的变化可以补偿成像系统倾斜角度,减少倾斜所带来的图像变形。实验结果表明,构建的多光斑激光三角法测量光路能够准确快速的检测出倾斜角度变化。该方法可以应用在固体核径迹检测、面型检测等要求检测小角度变化的领域。
In microscopic measurement, the image inclination can distort the image. The traditional laser triangulation method is improved by using multi-light beam and a laser triangulation with multi-light spots was proposed to measure the inclination angle. Firstly, the laser beams expanded were separated by a double wedge, and formed four beams approximately parallel. Then, the four beams were projected to the plane mirror, and became four spots in CCD after reflected. The multi-light spot optics system could avoid the effects of translation because the distance between the four spots was only related to the inclination angle and not sensitive to the translation. By calculating the distance between four spots, the inclination angle could be compensated, therefore the image distortion was reduced. Experimental results show that the optical device, based on laser triangulation method with multi-light spot, could measure the inclination of microscopic image accurately and fast. It can be applied wildly, such as solid state nuclear track detectors, topography measurement and so on.