论文信息 - High-density near-field readout over 100-GB capacity using a solid immersion lens with NA of 2.05

High-density near-field readout over 100-GB capacity using a solid immersion lens with NA of 2.05

We have achieved high density near field readout of a 100 GB capacity (69.5 Gbit/in2) disc by using a solid immersion lens with numerical aperture of 2.05. In order to realize the solid immersion lens wtih numerical aperture of 2.05, the solid immersion lens was made from Bi4Ge3O12 mono-crystal. The refractive index of Bi4Ge3O12 is 2.23 at the wavelegnth of 405 nm. A conventional optical pick-up actuator with the solid immersion lens was used for the near field optical disc system. We confirmed that the near field readout system is promising method of realizing a high density optical disc system.

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