Improved air gap controller for solid immersion lens-based near-field recording servo system

Jung Gon Kim, Won Ho Shin, Jun Jeong, Kyoung Su Park, No Cheol Park, Hyun Seok Yang, Young Pil Park

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

The near-field air-gap controller for solid immersion lens (SIL)-based near-field recording (NFR) systems has been required to improve its robustness to dynamic disturbances associated with rotating conditions such as periodic disk resonance and external shock. These dynamic disturbances usually exist in optical disk drive systems as a result of the operating condition. Moreover, SIL based NFR servo systems should be considered to realize stable servo systems because it is essential that the air gap between the SIL and the rotating disk should be less than 100nm and that the SIL and the disk should be protected. Hence, we propose improved air-gap control methods using internal model principle (IMP)-based and dead-zone nonlinear controllers. To increase air gap control performance with respect to dynamic disturbances, the IMP-based control method, which is one of the improved control methods for eliminating periodic disturbances at some frequencies, is implemented in the original NFR servo system. In addition, in case of anti-shock control performance, the original air gap servo system should be improved in terms of the anti-shock control such that the actuator head with SIL optics has to maintain on extremely small air gap to avoid collision between the SIL and the media when external shock is applied to the NFR system. Consequently, the experimental results show that the gap error signal is reduced by 76% during vibration of the disk using an IMP-based controller, and antishock control performance under external shock is improved by 60% using a dead-zone nonlinear controller.

Original languageEnglish
Article number03A044
JournalJapanese Journal of Applied Physics
Volume48
Issue number3 PART 2
DOIs
Publication statusPublished - 2009 Mar 1

Fingerprint

Servomechanisms
submerging
Lenses
near fields
controllers
recording
lenses
Controllers
air
shock
Air
disturbances
error signals
optical disks
rotating disks
Rotating disks
Optics
Actuators
actuators
optics

All Science Journal Classification (ASJC) codes

  • Engineering(all)
  • Physics and Astronomy(all)

Cite this

Kim, Jung Gon ; Shin, Won Ho ; Jeong, Jun ; Park, Kyoung Su ; Park, No Cheol ; Yang, Hyun Seok ; Park, Young Pil. / Improved air gap controller for solid immersion lens-based near-field recording servo system. In: Japanese Journal of Applied Physics. 2009 ; Vol. 48, No. 3 PART 2.
@article{86f01f1851ef4570a7accf6d71e0a8db,
title = "Improved air gap controller for solid immersion lens-based near-field recording servo system",
abstract = "The near-field air-gap controller for solid immersion lens (SIL)-based near-field recording (NFR) systems has been required to improve its robustness to dynamic disturbances associated with rotating conditions such as periodic disk resonance and external shock. These dynamic disturbances usually exist in optical disk drive systems as a result of the operating condition. Moreover, SIL based NFR servo systems should be considered to realize stable servo systems because it is essential that the air gap between the SIL and the rotating disk should be less than 100nm and that the SIL and the disk should be protected. Hence, we propose improved air-gap control methods using internal model principle (IMP)-based and dead-zone nonlinear controllers. To increase air gap control performance with respect to dynamic disturbances, the IMP-based control method, which is one of the improved control methods for eliminating periodic disturbances at some frequencies, is implemented in the original NFR servo system. In addition, in case of anti-shock control performance, the original air gap servo system should be improved in terms of the anti-shock control such that the actuator head with SIL optics has to maintain on extremely small air gap to avoid collision between the SIL and the media when external shock is applied to the NFR system. Consequently, the experimental results show that the gap error signal is reduced by 76{\%} during vibration of the disk using an IMP-based controller, and antishock control performance under external shock is improved by 60{\%} using a dead-zone nonlinear controller.",
author = "Kim, {Jung Gon} and Shin, {Won Ho} and Jun Jeong and Park, {Kyoung Su} and Park, {No Cheol} and Yang, {Hyun Seok} and Park, {Young Pil}",
year = "2009",
month = "3",
day = "1",
doi = "10.1143/JJAP.48.03A044",
language = "English",
volume = "48",
journal = "Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes",
issn = "0021-4922",
publisher = "Japan Society of Applied Physics",
number = "3 PART 2",

}

Improved air gap controller for solid immersion lens-based near-field recording servo system. / Kim, Jung Gon; Shin, Won Ho; Jeong, Jun; Park, Kyoung Su; Park, No Cheol; Yang, Hyun Seok; Park, Young Pil.

In: Japanese Journal of Applied Physics, Vol. 48, No. 3 PART 2, 03A044, 01.03.2009.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Improved air gap controller for solid immersion lens-based near-field recording servo system

AU - Kim, Jung Gon

AU - Shin, Won Ho

AU - Jeong, Jun

AU - Park, Kyoung Su

AU - Park, No Cheol

AU - Yang, Hyun Seok

AU - Park, Young Pil

PY - 2009/3/1

Y1 - 2009/3/1

N2 - The near-field air-gap controller for solid immersion lens (SIL)-based near-field recording (NFR) systems has been required to improve its robustness to dynamic disturbances associated with rotating conditions such as periodic disk resonance and external shock. These dynamic disturbances usually exist in optical disk drive systems as a result of the operating condition. Moreover, SIL based NFR servo systems should be considered to realize stable servo systems because it is essential that the air gap between the SIL and the rotating disk should be less than 100nm and that the SIL and the disk should be protected. Hence, we propose improved air-gap control methods using internal model principle (IMP)-based and dead-zone nonlinear controllers. To increase air gap control performance with respect to dynamic disturbances, the IMP-based control method, which is one of the improved control methods for eliminating periodic disturbances at some frequencies, is implemented in the original NFR servo system. In addition, in case of anti-shock control performance, the original air gap servo system should be improved in terms of the anti-shock control such that the actuator head with SIL optics has to maintain on extremely small air gap to avoid collision between the SIL and the media when external shock is applied to the NFR system. Consequently, the experimental results show that the gap error signal is reduced by 76% during vibration of the disk using an IMP-based controller, and antishock control performance under external shock is improved by 60% using a dead-zone nonlinear controller.

AB - The near-field air-gap controller for solid immersion lens (SIL)-based near-field recording (NFR) systems has been required to improve its robustness to dynamic disturbances associated with rotating conditions such as periodic disk resonance and external shock. These dynamic disturbances usually exist in optical disk drive systems as a result of the operating condition. Moreover, SIL based NFR servo systems should be considered to realize stable servo systems because it is essential that the air gap between the SIL and the rotating disk should be less than 100nm and that the SIL and the disk should be protected. Hence, we propose improved air-gap control methods using internal model principle (IMP)-based and dead-zone nonlinear controllers. To increase air gap control performance with respect to dynamic disturbances, the IMP-based control method, which is one of the improved control methods for eliminating periodic disturbances at some frequencies, is implemented in the original NFR servo system. In addition, in case of anti-shock control performance, the original air gap servo system should be improved in terms of the anti-shock control such that the actuator head with SIL optics has to maintain on extremely small air gap to avoid collision between the SIL and the media when external shock is applied to the NFR system. Consequently, the experimental results show that the gap error signal is reduced by 76% during vibration of the disk using an IMP-based controller, and antishock control performance under external shock is improved by 60% using a dead-zone nonlinear controller.

UR - http://www.scopus.com/inward/record.url?scp=77952538124&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77952538124&partnerID=8YFLogxK

U2 - 10.1143/JJAP.48.03A044

DO - 10.1143/JJAP.48.03A044

M3 - Article

VL - 48

JO - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes

JF - Japanese Journal of Applied Physics, Part 1: Regular Papers & Short Notes

SN - 0021-4922

IS - 3 PART 2

M1 - 03A044

ER -