Abstract：To address the issue of the lack of appropriate calibration equipment and methods for high-precision spectral confocal sensors, this study began by analyzing the measurement principles of spectral confocal sensors. Subsequently, a calibration method based on laser interferometry was proposed, and the corresponding calibration apparatus was developed. In addition to this, the study introduced a wavelength multiplicative interval measurement approach to reduce the influence of non-linearity errors in laser interferometers on measurement results. An algorithm based on the least squares principle was designed to correct measurement point positions.In order to validate the feasibility of the proposed calibration method, relevant measurement experiments were conducted. The experimental results demonstrated that within a measurement range of (0~100) μm, the indication error was ±0.04%FS, repeatability was 0.01%FS, and linearity was 0.03%FS. The uncertainty of indication error measurement results was found to be U=10 nm (k = 2).Furthermore, the calibration apparatus constructed for a measurement range of (0~52) mm exhibited an uncertainty of U=2 nm +2×10-7L(k = 2) for indication error measurement results. The research content and its results have had significant implications for addressing the traceability challenges of high-precision spectral confocal sensors. Furthermore, it provided valuable reference for the development of similar calibration installations.
2024, Vol. 45 
