| 摘要 |
PURPOSE:To obtain a laser device, which can control coherence without widening the spectral distribution of a light source, by splitting the light from a laser light source, into two light beams, overlapping the light, which has passed a first dispersing medium, and the light, which has passed a second dispersing medium and an optical-path-length adjusting device, and outputting the result. CONSTITUTION:The light from a laser light source 1 is split into two light beams through a splitter 2. The one split light is made to pass a first dispersing medium 3. The other light is made to pass a second dispersing medium 4, which has the different dispersing value from the first dispersing medium, and an optical-path-length adjusting device 5. The light, which has passed said first dispersing medium 3, is overlapped with the light, which has passed the second dispersing medium 4 and the optical-path-length adjusting device 5, in a wave combiner 6, and the result is outputted. Thus, with the spectral purity of the light source as a basis being maintained intact, only the coherence is freely adjusted by changing the dispersion values of the dispersing media 3 and 4, the lengths of the media and the difference between two optical paths. |
