An Optical Configuration Based on Flying Head Structure for Near-Field Recording

Abstract

We report an optical configuration with a flying head for a near-field recording system. The configuration consists of a fixed optical unit and condensing optics based on the flying head structure. While the fixed optical unit includes a light source and a signal-detection unit, the condensing optics include a solid immersion lens (SIL) embedded in the flying slider and infinite objective lens arranged on the flying slider. Free-space propagation using a collimated beam is employed to optically connect these two units. After we investigated the head structure and its fabrication process, we evaluated the fabricated optical flying head, both as an optical head and a flying head. The jitter was 8.87% when the shortest mark length was 0.364 µm. The C/N ratio was 49.53 dB for 0.2 µm of the mark length. The tolerances of relative tilt and decenter between the two optical axes of the fixed optical unit and the condensing optics which were derived experimentally were ±0.3 deg and ±150 µm. These results suggest that the optical configuration is adequately practical even for use in mass production.

Three-Dimensional Optical Recording in tert-Butoxycarbonyl-Protected Quinizarin Methacrylate Polymers

“…6. [25][26][27] The head, which consists of a truncated hemispherical solid-immersion lens (SIL) embedded in the flying slider with an infinite objective lens on the flying slider, functions as an infinite focusing optics with NA > 1. In recording and reading out signal data via evanescent waves, the head flies above the recording medium, with its flying height maintained at several tens of nanometers.…”

“…6, linear velocity must be carefully considered not only to maintain a proper flying attitude and an adequate flying height but also to obtain a practical transfer rate to handle a terabyte or more of recording data. 25,26) Although optimal linear velocity depends on the mass and height of a flying slider, the minimal target of the linear velocity is 1 m/s. To realize a practical terabyte 3D optical memory system using the t-BQzMA polymer-based recording medium, therefore, it is necessary to confirm that recording at 1 m/s speed or more can be achieved in the recording medium.…”

A tracking motion approach for a piezotube actuator in a disk drive subject to disk deformation and disturbance

“…Therefore, in the near field the passive air bearing and voice coil motor hardly meet both the focusing and track-following requirements. 1 Author to whom any correspondence should be addressed. Wu and Liu [5] designed a PZT bender actuator in an NFODD to control the air gap.…”

Control Experiment on Pickup Head Flying above Rotating Disk

“…EAR-FIELD optical disk derives represent one of potential devices [1][2], for which a capable servo system must be constructed to facilitate reading and writing. To achieve high precision in focusing for near-field data recording, it is essential to develop servo systems that can maintain a constant height at which the pickup head flies above a rotating disk.…”