1993 年 42 巻 479 号 p. 1004-1010
Cutting of brittle materials such as glass is usually made with a diamond scriber or a rotary roller chisel. It is said that the mechanical cutting of glass using the scriber or the chisel leads to lower cutting quality. A non-contacting cutting method using a CO2 laser is recently being studied enthusiastically. Precision breaking of glass and other brittle materials, however, has not been made.
Breaking of transparent glass plates with a YAG laser was studied after the surface of the specimen was painted in marker ink (magic ink). Ink was used as an absorber of laser beam. And also, the influence of surface roughness on breaking was investigated. It was found from the experiments that painting of magic ink had a considerable effect on breaking of glass, especially in blue color. Chamfering of the corner of the specimen by lapping yielded easy breaking and it reflected directly to high quality breaking of glass.