摘要 |
The optical recording apparatus focusses a light beam, emitted from a laser light source, by an objective lens, applied in this state to an optical information recording medium. In the optical path between the laser light source and the objective lens is disposed a diffraction grating inclinedly with respect to the optical axis. This diffraction grating not only reflects the light beam emitted from the laser light source but also separates it into zero order as well as +1st order and -1st order diffracted light beams. Thus, this diffraction grating functions not only as a diffraction grating but also as a mirror.
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