| 摘要 |
PURPOSE:To observe a machining state in the direction of depth of a material to be machined which is at work in a real time by establishing an interference optics section in an observation optics system of a laser beam machine. CONSTITUTION:Illumination from an illuminating lamp 21 is changed by a polarizer 29 into a linear polarization and after the azimuth of this linear polarization is converted by a lambda/4 plate 31 into a desired azimuth, the illumination is made incident on a prism 28. The linear polarization which enters the prism 28 is divided into two beams in which oscillating surfaces are at right angle with each other and the material 15 to be machined is illuminated. The bisected laser beams are reflected by the material 15 to be machined, enter the prism 28 again and are joined as the oscillating directions are orthogonally crossed. An analyzer 30 is inserted into an observation optical path provided with a camera 25, takes out common oscillation components of the beam outgoing from the prism 28 to cause interference. An interference contrast is obtained by the material 15 to be machined and the material 15 to be machined can be observed cubically by an interference contrast image reflected to a surface state of the material 15 to be machined. |
