| 摘要 |
<P>PROBLEM TO BE SOLVED: To accurately reproduce information from an optical disk with simple constitution. <P>SOLUTION: When an optical disk apparatus 10 reproduces information from an optical disk 100, it converges a reading light beam LD emitted from an LED 61 by an objective 18 to form substantially collimated light and projects it to the optical disk 100 to cause it to be reflected by a reflection surface 102 so as to make it become a reading reflected light beam LDR. Then, the apparatus converges the reading reflected light beam LDR by a mark layer selection lens 55, detects the reading reflected light beam LDR passing through a target position PG by a detection region X located at the confocal point of the target position PG and generates a detection signal U2. Subsequently, the apparatus recognizes the presence or no presence of a recording mark RM on the basis of the detection signal U2 to reproduce the information. Thus, the apparatus can detect the passing state of the reading reflected light beam LDR in the target position PG and can recognize the presence or no presence of the recording mark RM on the basis of the detection result. <P>COPYRIGHT: (C)2010,JPO&INPIT |
