BEAM SCANNER AND SURFACE MEASUREMENT APPARATUS

摘要

PURPOSE: A beam scanner and an apparatus for measuring a surface are provided to improve the precision of a surface measurement by minimizing errors according to the movement of a rotary mirror. CONSTITUTION: A rotary mirror(102) includes an upper and a lower reflecting surface and a plurality of lateral reflecting surfaces. The rotary mirror rotates around a rotary shaft and scans beam, which is radiated on the lateral reflecting surfaces, to one direction. The rotary shaft passes through the upper and the lower reflecting surface. First light source(101) radiates first beam toward the lateral reflecting surfaces. Second light source radiates second beam toward either of the upper reflecting surface and the lower reflecting surface. A detector(104) receives reflected second beam from a rotary mirror.