| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique of identifying a reflection surface having reflected a laser beam output from a laser source simply and in a short time among a plurality of reflection surfaces formed in a polygon mirror.SOLUTION: A light scanning device according to the present invention detects, by means of a BD sensor, a laser beam that is output from a laser source and reflected at each reflection surface of a polygon mirror having a plurality of reflection surfaces, and associates detection intervals with respective reflection surfaces so as to measure them as detection cycle data. The light scanning device extracts a fundamental wave component which is included in a signal constituted by detection cycle data by the number of surfaces of the polygon mirror and whose one cycle is a range by the number of surfaces so as to calculate a phase of the fundamental wave component. The light scanning device further compares the calculated phase of the fundamental wave component with phase information associated in advance with each of the plurality of reflection surfaces of the polygon mirror, to thereby identify a reference reflection surface which serves as a reference for identifying a reflection surface having caused a laser beam output from the laser source to be reflected. |
