レーザ照射処理におけるカライドスコープによるエネルギー密度分布の変換 テーパ管のカライドスコープ

Abstract

A method is proposed to convert the energy density distribution of the laser beam to an adequate one for laser processing by applying a kaleidoscope of taper pipe taking a case of CO2 laser as an example. The energy density distributions of singlemode and multi-mode laser beams obtained by a kaleidoscope of taper pipe were calculated for cases in which the interferences of the beams were disregarded and also the interferences were taken into consideration. It is confirmed that the energy of the laser beam can be concentrated to its center in narrow ranges with use of the kaleidoscope of taper pipe. The optimum geometries of the kaleidoscope are also obtained through the calculations to concentrate the energy density distribution. In order to confirm the effect of the kaleidoscope, experiments were carried out to measure the energy density distribution of single-mode laser beam with use of the knife edge method, and the acrylic burn patterns were made with the single-mode laser beams concentrated by different methods. The experimental results were in good agreement with the calculations.