An optical configuration based on flying head structure for near-field recording

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 ±0.3deg and ±150 μm. These results suggest that the optical configuration is adequately practical even for use in mass production.