2002 年 5 巻 4 号 p. 385-388
We have proposed a new focusing/tracking error signal detection method using a holographic optical element (HOE), and reported the evaluation results with this HOE-LD/PD integration unit carried in the optical pickup. In this error signal detection system, focusing and tracking error signals are detected with sub beam spots generated by the HOE, and the main beam spot is used only for RF signal detection. For this reason, it is not necessary to use multi-segment PD for RF signal detection. Therefore, improvement of the RF signal response is expected to become easy. Basic operation of the optical pickup using this new HOE was examined experimentally, and good results were obtained.