1997 年 63 巻 12 号 p. 1701-1704
Kaleidoscope is a device to convert power density distribution of laser beam. Cylindrical pipe kaleidoscope and taper pipe kaleidoscope are applied to laser drilling process in the present research. The shapes and dimensions of the kaleidoscopes are designed based on the theoretical analysis of the power density distribution of the laser beam converted by the kaleidoscopes. Laser drilling experiments of acrylic resin plates are carried out by applying both the kaleidoscopes and the conventional lens. The experimental results are discussed from the viewpoints of the depth and the cylindricity of the acrylic burn patterns. The following remarks are concluded based on the experiments. The shapes and dimensions of the burn patterns are not affected so much by the distances between the kaleidoscopes and the work plates in the case of drilling process by use of the kaleidoscopes. The taper pipe kaleidoscope is most suitable for the drilling process from the viewpoint of the cylindricity of the burn patterns.