Abstract
In this paper, we report on a first-surface recording demonstration using a flexible monolithic optical head slider[1][2] and lens-less detection optics. To miniaturize the detection optics, we directly located an avalanche photo diode (APD) sensor in close proximity to the medium, and by minimizing the detector-to-medium spacing, a lens-less detection system was constructed. The light collection efficiency was equivalent to that of 0.36 NA objective lens, and can be improved to be equivalent to 0.6 NA. Using this detection method, we successfully demonstrated a lens-less signal readout of 0.8 μm line-and-space pattern at 4.2 m/s linear velocity (2.6MHz). The effect of misalignment of the head and the detector is also discussed.
