| 摘要 |
PURPOSE:To secure the energy of light freezing without enhancing the accuracy of timing control and the intensity of a laser beam at light freezing time by at least equipping the title device with a control means to control a two-dimensional scanner so as to decrease the scanning speed of the laser beam. CONSTITUTION:When a trigger switch is turned ON, a system controller compares picture data in a retained control point with picture data in a real- time control point. The system controller omits raster scan in a case when ordinary observation is to be executed at a position where the light freezing is to be executed and at positions before and behind the above-mentioned position and switches to vector scan. Since the vector scan can be executed only when a reciprocating scanner such as an acoustooptical element and a galvanomirror is used, when a rotating scanner such as a polygonmirror is to be used as a horizontal scanner, a scanning system is kept in the raster scan as it is, the scanning speed is decreased to a low speed, and the energy at the time of the light freezing is secured. |
