| 摘要 |
PURPOSE:To improve the precision in measurement by measuring the position of a light-sensing element by two laser beams projected with a prescribed angle between them within a plane of rotation and by a laser beam rotating and moving symmetrically with the laser beam A or B. CONSTITUTION:A laser beacon 1 projects laser beams A and B, rotating them in the same direction with a prescribed angle theta0 held between them by rotating first and second rotary tables 21 clockwise integrally at a prescribed angular speed, while projecting a laser beam C, rotating it in the direction opposite to that of the laser beams A and B. A time difference computing element 41 transmits the time of reception of the laser beam A as a reference time signal to an angle computing element 43. In a distance computing element 42, a distance is calculated by using a light reception time difference DELTAtz sent from the time difference computing element 41, the angle theta0 formed by the two laser beams A and B and being the set condition and the width W1 of a photosensor. |
