Narutoshi Fukuzawa

Properties of Super-Resolution Near-Field Structure with Platinum-Oxide Layer in Blu-ray Disc System

The super-resolution near-field structure with a platinum-oxide layer was applied to the Blu-ray Disc system. The carrier-to-noise ratios of 50.1, 46.2, and 39.2 dB were obtained at the mark lengths of 75, 50, and 37.5 nm, respectively, which are smaller than the resolution limit of 119 nm of the optics. Mark position recording with a mark length of 50 nm was also attempted, and we succeeded in retrieving recorded patterns correctly without loss of the signal.

Bit Error Rate Characteristics of Write Once Read Many Super-Resolution Near Field Structure Disk

We firstly report the bit error rate (bER) characteristics of a super-resolution near-field structure (super-RENS) write-once read-many (WORM) disk in a blue laser optical system, (laser wavelength 405 nm, numerical aperture 0.85) with a carrier-to-noise ratio (CNR) at the 75 nm mark (50 GB Capacity) of 47 dB and a low frequency noise of approximately 20 dB. The recording state should be precisely controlled by an adequate writing strategy for bER measurement. Together with the above conditions, using the frequency-dependent gain controlled equalization (EQ) and advanced partial-response maximum likelihood (PRML) technique, bER of 10-3 order at 50 GB was obtained.