Abstract
A compact and high sensitive angle detector for the measurement of surface undulation is proposed. It was constructed for making a sampling time brief. The detector consists of a vessel holds mercury and an optical system. It detects an inclination of a vessel based on a surface of mercury. The experiment about the dynamic character and the drift made the sensitiveness of the detector clear. The calibration by the autocollimator was performed, and it was examined in comparison with autocollimator by measurement of the surface undulation. According to the result, it was confirmed that the detector is smaller than 75mm×75mm×65mm, has high accuracy less than 1" based on the drift data, ±3" based on the calibrated data, and needs a few seconds to get stability of output when the detector is set at the sampling point. At the measurement of the surface undulation, the result gained by the detector coincided with the result by autocollimator.
