Patent ID: 7206269

Claim:
An optical disk apparatus, comprising: an optical pickup configured to irradiate an optical disk with a beam, to receive light reflected from the optical disk, and to convert the reflected light into an electrical signal; a signal processing component including: a reproduction system circuitry configured to generate a reproduction signal used in restarting recording of the optical disk after an interruption, based on the electrical signal from the optical pickup and setting values; speed information detection circuitry configured to detect speed information before or after an interruption of a recording on the optical disk based on the electrical signal from the optical pickup; and position detection circuitry configured to detect a recording restart position and a current position of the optical disk; an accessing unit configured to control the optical pickup to access the optical disk at the recording restart position from the current position of the optical disk; and a setting unit configured to set in the reproduction system circuitry setting values based on the detected speed information, the setting values being used by the reproduction system circuitry to generate the reproduction signal, wherein the reproduction system circuitry comprises: an equalizer circuit configured to extract an information signal of the optical disk from the electrical signal sent from the optical pickup so as to perform a waveform equalization and a group delay smoothing of an EFM signal; an HPF circuit configured to suppress a fluctuation in binary voltage level of the EFM signal when a scratch passes; a binarization circuit configured to binarize the signal sent from the HPF circuit; a PLL circuit configured to generate a synchronizing clock from the binarized signal; a demodulation circuit configured to convert information written on the optical disk into a digital data string by using the binarized signal and the synchronizing clock; and a scratch zone detection circuit configured to generate scratch zone information by using the information signal of the optical disk obtained by the optical pickup, wherein the setting values comprise at least one of frequency characteristics of the equalizer circuit and the HPF circuit, response characteristics of the binarization circuit, gains of the PLL circuit and the servo circuit, or a time constant of the scratch zone detection circuit.