Non-contact surface thermal deformation measurement based on chromatic confocal sensor

Chromatic confocal sensors are widely used in chip processing, high-precision instrument manufacturing, industrial testing and other fields because of high-precision displacement recognitioncapabilities. This research combines a chromatic confocal device with resistance temperature detector for dynamic deformation measurement of heating pipeline. The system is suitable for the measuring range of 300 µm and resolution can reach 0.3 µm. Using finite element method to simulate thermal deformation of aluminium with a thickness of 2 mm, and obtaining simulation trends and results. The end face of aluminium is heated continuously and uniformly in experiment, recording the data of spectral, laser triangular displacement sensor, and temperature sensor at 10°C intervals, respectively. And using Gaussian fitting algorithm to obtain spectral peaks, the corresponding thermal deformation is obtained through the relationship between wavelength and axial displacement. The results show that the experimental data of the chromatic confocal sensor is consistent with the laser triangular displacement sensor basically, with a maximum standard deviation of 1.06. In addition, simulation and experimental trends are consistent.