| 摘要 |
PURPOSE:To obtain a kaleidoscope capable of reducing laser beam loss even when the kaleidoscope is so designed that the number of times of reflection is made large to obtain a uniform intensity distribution by using at least three beltlike reflecting mirrors made of metallic flat plates coated with thin films with small absorption loss. CONSTITUTION:The rectangular section of the kaleidoscope 73 is formed of four copper flat plates 72 coated with germanium thin films 71, whose film thickness (d) is determined as shown by a inequality (I). The germanium thin films 71 are easily formed by vapor deposition, sputtering, or electroplating the sectional shape of the kaleidoscope is a polygon such as a square and a rectangle matching an area to be irradiated with laser light. Consequently, the loss is small and the intensity distribution of irregular laser beam can be uniformed; when large electric power is used for the surface processing of metal, etc., the kaleidoscope is used suitably and the laser beam output of an oscillator is utilized effectively. |
