One-Beam Push–Pull Method with Simple Holographic Optical Element for Multilayer Blu-ray Discs

The use of a multilayer is efficient for increasing the recording capacity of optical discs, but the unnecessary layer cross talk affected by the stray light is also increased. Layer crosstalk should be suppressed to realize a stable tracking servo system. A one-beam push–pull method with a simple holographic optical element for a multilayer Blu-ray disc is proposed, and its effectiveness in suppressing the layer crosstalk was experimentally confirmed.