Development of a high-sensitivity dual-axis optoelectronic level using double-layer liquid refraction

Abstract To satisfy the requirements of precision angle measurement and machine leveling, a high-sensitivity dual-axis optoelectronic level using double-layer liquid refraction is proposed in this paper. Silicone oil, with a constant horizontal surface, is used as a reference. A double-layer liquid refraction principle is used to improve the level's sensitivity. An autocollimator is used as a detector of two-dimensional angle. Parallel-light paths are adopted to avoid interference from reflected light. When the level has a tilt angle, the light spot on the quadrant photodiode of the autocollimator is bound to shift. The sensitivity model of the level was established, and the level was designed and tested. Experimental results revealed that the level has a resolution of 0.05 arcsec, a range of ± 150 arcsec, a repeatability of 0.4 arcsec, and a stability of ± 0.2 arcsec. It can be used to measure tilt with a high-precision requirement.