| 摘要 |
PROBLEM TO BE SOLVED: To suppress the projection of a laser beam to improper projection destination.SOLUTION: A projection destination determination device comprises: a laser emission part 2 for projecting a laser beam by line scanning in a horizontal direction; a reflection light detection part 3 for detecting an intensity of reflection light on a projection destination of the laser beam; a differentiation part 4 for time differentiating a detection intensity of the reflection light; a comparator 5 for determining the necessity of suppressing laser beam projection on the basis of a time differential value of the detection intensity of the reflection light; and a projection suppression part 7 for, when the projection destination of the laser beam is determined to be an improper projection plane, bringing a shutter part into a closed state to stop projecting the laser beam under control of a control part 6. |
