Structural Parameter Analysis and Optimization of Laser Triangulation Sensor Using Commercial Lens

The article investigates the structural parameters of a laser triangulation measurement system (LTMS) based on the utilization of commercial lenses and offers a basis for choosing the most suitable configuration. First, the object-image relationship model and the optical sensitivity model of the LTMS are studied respectively. The Scheimpflug condition and transverse magnification of a given point on the axial field are used to reduce the number of unknown parameters in the model. Furthermore, the values of the magnification and resolution are preliminarily determined by means of focal length, sensor size, and measurement range. Moreover, the optimum acceptance angle is concluded based on the maximum sensitivity of the LTMS. Finally, the selected parameters are evaluated by nonlinear error. The experimental results demonstrate that optimizing the structural parameters of the LTMS can elevate the nonlinearity to nearly twice its original value compared to the structural parameters without optimization, under the identical hardware configuration. Selecting the acceptance angle based on maximum sensitivity has rationality in terms of the nonlinear error results.