| 摘要 |
PURPOSE:To eliminate a decrease in an optical intensity due to a distance from a lens and to obviate the adverse influence of a disturbance light to visualized measurement by emitting a parallel laser beam to be incident and providing a laser enlarging unit for emitting a laser light sheet enlarged in parallel in one direction. CONSTITUTION:A laser light source 1 for emitting a laser beam 2, a collimator 3 for regulating the beam 2 to a parallel beam, and a laser beam enlarging unit 5 for enlarging a parallel beam 4 obtained from the collimator 3 in parallel only on one direction are provided. Here, the beam 2 having a diameter D0 and emitted from the source 1 is corrected to a parallel beam 4 having a diameter Di by a collimator lens 3a having a focal distance fa and a collimator lens 3b having a focal distance fb. An optimum parallel beam 4 is obtained by regulating an interval between the lenses 3a and 3b. Further, the beam 4 becomes a laser light sheet 7 which is enlarged in parallel only in one direction in a plane including an optical axis by a cylindrical lens 5 having a focal distance fc and a cylindrical lens 6 having a focal distance fd to be of a thickness Di and a width (fd/fc) Di. |
