Abstract
A new position sensing system, which is composed of a 2-D angle gril and a 2-D angular sensor, is proposed. The angle grid has a 2-D angular information pattern on the surface. The relative displacements between the angle grid and the angular sensor in the X and Y directions can be detected from the output of the angular sensor. Furthermore, use of an optical scanning angular sensor, which can scan a beam spot on the angle grid, can reduce the effect of the form error of the angle grid. Using constant speed scanning, the scale of the angle grid can be interpolated from time scale. In this paper, a signal processing system utilizing high-speed pulse generation and count circuits is designed to achieve high speed position detection. The experimental result of this position detection is reported.
