Uncertainty analysis and optimization design of long-distance laser triangulation displacement sensor applied to dynamic object

The principle of laser triangulation has been widely used in various high-precision measurement due to its advantages of high accuracy, fast response speed and simple structure. However, the laser triangulation method still has some limitations for the measurement of dynamic object, and the accuracy of laser location will be significantly reduced especially when the working distance becomes longer. We have carried out the development and performance optimization of a long-distance laser triangulation displacement sensor for the application of dynamic object. The measurement uncertainty is analyzed when the laser dithering, laser drifting and object motion are all taken into account. Then, reflectors are added to the optical path structure of traditional laser triangulation system with the aim to improving its sensitivity and expanding its working range. The experiment results show that the repeatability of our designed optical system is 0.34 mu m and the imaging uniformity is 86.23% when the working distance is of 1300mm.