Abstract
A mode-switching servo is widely used in solid immersion lens (SIL)-based near-field recording (NFR) systems to control the air gap between the bottom surface of the SIL and the top surface of the rotating media. In the mode-switching servo, it is very important to reduce the initial overshoot in the near field region, as this overshoot can cause collisions between the SIL and the media, and increase the settling time required for the SIL to be initially moved to the final air gap. In this paper, the mode-switching servo with a brake pulse is proposed to reduce the initial overshoot and settling time. The effectiveness of the proposed method is proved by experiments of which results show that the minimum air gap due to the initial overshoot is improved from 6.86 to 18.73 nm and the settling time is reduced from 30 to 4.5 ms.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Ichimura I, Hayashi S, Kino GS (2003a) Gap servo system for a biaxial device using an optical gap signal in a near-field readout system. Appl Opt 42(19):2719–2724
Ishimoto T, Saito K, Shinoda M, Kondo T, Nakaoki A, Yamamoto M (2003b) Gap servo system for a biaxial device using an optical gap signal in a near field readout system. Jpn J Appl Phys 42(5A):2719–2724
Kim JG, Kim TH, Choi H, Yoon YJ, Jeong J, Park NC, Yang HS, Park YP (2007a) Improved air-gap control for SIL based near-field recording system. IEEE Trans Magn 43(2):811–813
Kim JG, Kang MS, Kwon TW, Jeong J, Park NC, Yang HS, Park YP (2007b) Improved gap control for SIL based near-field recording system. Technical Digest of ISPS07, Santa Clara, USA
Lee JI, van der Aa M, Verschuren C, Zijp F, van der Mark M (2005) Development of an air gap servo system for high data transfer rate near field optical recording. Jpn J Appl Phys 44(5B):3423–3426
Lim HJ, Han CS, Kim SH (2000) Reduction of seek time of tracking actuator with pulsed excitation in optical disk. Jpn J Appl Phys 39(12A):6546–6549
Ogawa M, Nakajima Y, Koyanagi K, Furukawa T (1993) Rapid-access system for optical disk drive using feedforward brake pulse. Jpn J Appl Phys 32(11B):5376–5380
Acknowledgments
This work was funded by the Korea Science and Engineering Foundation (KOSEF) through the Center for Information Storage Mechatronics (CISM) Grant No. R17-2008-040-01001-0. We would like to acknowledge that Samsung Corporations have kindly provided us with technical supports on our experiments.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Kim, JG., Kang, MS., Shin, WH. et al. Improved gap servo system using a brake pulse for a SIL-based near-field recording system. Microsyst Technol 16, 309–315 (2010). https://doi.org/10.1007/s00542-009-0896-0
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00542-009-0896-0