High-Precision Roll Measurement Method Based on Laser Polarization

Linear guides are essential components of precision equipment, such as computer numerical control machine tools and coordinate measuring machines. The key to improving their accuracy is to conduct high-precision measurements and effectively compensate for the six degrees of freedom errors that emerge during motion. However, the roll is a difficult parameter for achieving high-precision measurements in laser measurements, and it has yet to be effectively addressed. This study presents a high-precision and high-sensitivity roll measurement method based on the laser polarization state. The method employs a quarter-wave plate as the roll angle sensitive component. Firstly, the feasibility of this method was assessed through the Jones matrix and Zemax simulations. Subsequently, both theoretical and experimental analyses were conducted to evaluate the impact of using a corner cube reflector as a retroreflector on roll measurements. Finally, a corresponding measurement device was developed, and a series of comprehensive experiments were executed. The experimental findings indicate a measurement sensitivity of 7 mV/arcsec for this method. In comparison to commercial autocollimators, the contrast deviation within ± 100 arcsec is ± 1 arcsec. The repeatability of measurements on the air-floating guide rail is 1.3 arcsec, with a maximum contrast deviation of 2.5 arcsec compared to the electronic level. Thus, the proposed method offers the advantages of high precision, simple structure, and low cost and provides a new technique for high-precision roll measurement.