| 摘要 |
<p>An optical pickup for high-density recording/reproducing, which can read closely packed recorded information which exceeds the limits normally associated with a given cut-off frequency, the pickup including an objective lens (18, 18') having divided portions (20-22, 20'-22') for respectively transmitting a zero-order optical component and +/-1st-order diffracted components. To detect a signal for reproduction, a focusing lens (28) is used for focusing the zero-order component and +/-1st-order diffracted components passing through the objective lens (18, 18') so as to be mutually interfered. Stable high-density optical recording/reproduction can be realized regardless of the numerical aperture of the objective lens (18, 18') and optical wavelength. <IMAGE></p> |
