| 摘要 |
PURPOSE:To narrow the band of a laser light at the time of laser oscillation and to efficiently oscillate by providing a distributed feedback structure in a gas laser tube for a short pulse oscillation. CONSTITUTION:A distributed feedback structure 9 is formed of an optical material having a pectinated toothed uneven shape on the passage of a layer light 1. The refractive index n1 of the structure 9 is selected to a value higher than the refractive index n0 of laser gas 7. When the wavelength of a periodic structure of the uneven part is lambda, lambda2 2 lambda1 is satisfied with respect to a laser oscillation wavelength lambda2. Here, the symbol ( ) of near equality is employed because it is influenced by the nonlinearity of a laser medium. The feedback structure is introduced into the oscillation unit of a laser tube 2. Thus, only the light 1 of the wavelength indicated by the formula is oscillated, injection of energy to a discharge 6 is conducted with this wavelength to oscillate in the narrow band with high oscillation efficiency. |
