OSZILLATOR FÜR FREIE-ELEKTRONEN-LASER

In a free-electron laser oscillator, two laser beams (LB1, LB2) having different wavelengths are irradiated to a photoemitter (3) to generate an electron beam (EB). The electron beam (EB) is density-modulated by a frequency corresponding to a difference between frequencies of the two laser beams (LB1 LB2), and accelerated to a vicinity of light velocity by a microwave. Such a relative theory electron beam is directed into a periodical magnetic field generated by a helical wigglar (6) and a track thereof is deflected. As a result, a synchrotron radiation light is generated from the relative theory electron beam. The radiation light generates an electromagnetic field by itself. Thus, electromagnetic interaction takes place among the electromagnetic field, the periodical magnetic field and the relative theory electron beam, and the laser oscillation is started. A power of the laser beam (LB) irradiated to the photoemitter (3) may be reduced because the two laser beams (LB1 LB2) having different wavelengths are irradiated to the photoemitter (3) and the electron beam (EB) is bunched in accordance with the difference between frequencies.