| 摘要 |
PURPOSE:To reduce the thickness of a recording medium to the half, to miniaturize a device, and to improve and S/N of a reproducing signal by forming an optical recording film on a substrate by interposing a separation material layer, respectively, and performing recording and readout corresponding to a control signal, respectively. CONSTITUTION:On a transparent substrate 1, a recording film 2, a protection film 3, the separation material layer 4, the protection film 3, a recording film 5, and a protection layer 6 are formed, which constitute an optical recording medium. And incident light from an objective lens 11 is converged on the recording film 2, and optical thermal recording is performed, and similarly, the optical thermal recording is performed on the recording film 5 by the incident light from an objective lens 12. And at the time of writing on the recording films 23a and 23b of the optical recording medium 23, a voltage generation circuit 33 sends an offset voltage to a differential amplifier 32 by the output signal of a control circuit 34, and a focusing driving signal is formed corresponding to a focusing error signal from an optical head 31, and an incident laser beam is image-formed on the recording film 23a or 23b. |
