Mizuho Tomiyama

Three-Dimensional Recording with Electrical Beam Control

A concept of a novel optical storage system has been proposed, which has the large-capacity characteristic because of three-dimensional recording and readout, and high-reliability and low-power-consumption characteristics achieved by controlling a light beam focused in a recording medium electrically instead of mechanically. On the basis of this concept, an optics for microholographic recording was constructed, and electrical beam control elements that vary the position of focused spots in the recording medium in both in-plane and vertical directions were incorporated into the optics. Liquid crystal deflectors and liquid crystal variable-focus lenses were used as the electrical beam control elements for in-plane and vertical beam control, respectively. Plural bits were recorded and read out in both in-plane and vertical directions of the recording medium, and the concept has been experimentally demonstrated.