| 摘要 |
PURPOSE:To obtain synthetic beams, spectra of which extend over narrow zones and which has stable frequency and a high output, by converging outgoing beams from a plurality of laser diodes by a parabolic mirror, returning transmitted beams from a slit plate fitted at a focus to parallel beams again and extracting output beams from an external resonator. CONSTITUTION:Parallel outgoing beams P1, P1 reflected by first parabolic mirrors 21 by all laser diodes 11 are projected to a second parabolic mirror 22, and reflected by the mirror 22 and converged to a focus F for the mirror 22. A third parabolic mirror 23 having the same focus is also fitted, and a slit plate 24 is set up at a confocus, thus forming Fraunhofer diffraction. Emitted beams P2 transmitted through the slit plate 24 are converted into parallel beams P3 by the third parabolic mirror 23, and applied to an external resonator 25. Consequently, outgoing beams do not pass through a lens system at all, and are applied to the external resonator 25. thus narrowing the zones of spectra. Selection frequency at that time is determined by the slit of the slit plate 24. That is, the width of the slit is decided properly, thus fixing the frequency of output beams at a desired value. |
