| 摘要 |
PURPOSE:To change the wavelength of emitting beams into a single one by projecting emitting beams from a semiconductor laser to a hologram and returning reflected diffracted beams to the semiconductor laser while using transmitted zero-order beams or transmitted curved beams in incident beams as utilizing beams. CONSTITUTION:When a hologram 12 is irradiated by divergent spherical waves 21, primary diffracted energy E1, zero-order transmitted-beam energy E2, reflected primary diffracted-beam energy E3 and reflected-beam energy E4 are generated to incident-beam energy Ei. Primary diffracted-beam energy E1 and zero-order transmitted-beam energy E2 among them are used as utilizing beams, and reflected primary diffracted-beam energy E3 returns to an irradiation source by the same path as incident beams, and functions as the fixation of wavelengths. Accordingly, the front emitting beams of a laser diode are separated into utilizing beams and returning beams by the hologram, and only predetermined wavelength beams re returned to the laser diode, thus attaining the change of the wavelength of emitting beams into a single one by a small-sized module. |
