Optical Cap Sensor for Magneto-Optic Near-Field Recording

MO 근접장 기록을 위한 광학 갭 센서

  • 윤용중 (연세대학교 대학원 기계공학과) ;
  • 박재혁 (연세대학교 정보저장협동과정) ;
  • 박노철 (연세대학교 기계공학과) ;
  • 박영필 (연세대학교 대학원 정보저장협동과정)
  • Published : 2004.03.01


This paper proposes a new method of measuring an air interface distance between a solid immersion lens(SIL) applied magneto-optic technology and the disk surface. For applying near-field recording (NFR) technology to the magneto-optic storage devices for the next generation, it is positively necessary to maintain the small air gap under about 100㎚. We design an apparatus that consists of some optical components such as a prism, a polarizer and an analyzer. By using the Fresnel reflection coefficient equation, Jones matrices calculation and Malus's law, we establish a mathematical model for understanding the characteristics of the system. The simulations are based on the mathematical model and through the simulation results which is made with various cases we can estimate the performance of the new optical gap sensor system. Experimental results, which are also based on the mathematical model for specific cases, are in good agreement with simulated ones and demonstrate the possibility as the new optical gap sensor.


Magneto Optical Recording;Near-Field Recording;Polarized Light;Optical Gap Sensor


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