| 摘要 |
PURPOSE:To perform working with high accuracy with less loss in laser light without receiving the influence of a chromatic aberration by using laser light having a visible wavelength and reference light having the same wavelength as the wavelength of the laser light. CONSTITUTION:The beam from a laser oscillator 14 oscillating laser light 15 having a wavelength in a visible region is reflected by a polarizing beam splitter 18 and is irradiated onto a slit 5. On the other hand, the light from a reference light source 6 is transmitted through an interference filter 16, by which only the light having the same wavelength as the wavelength of the laser light 15 is transmitted and is irradiated onto the slit 15. The reference light 17 formed to a rectangular shape of an optional size by the slit 5 is reflected by a reflecting mirror 19 and the slit image reduced to the size which is the inverse number of the magnification of an objective lens 9 is formed on a work 10 by the lens 9. The operator adjusts the size of an aperture and positions to the same with the slit 5 according to the working region while observing said image through a polarizing plate 20, a prism 12 and an eyepiece lens 13. When the light 15 is oscillated, said light is imaged on the work 10 and the working in exactly the same position as the position imaged by the light 17 is made possible. |
