title: A new method of Q factor optimization by introducing two nodal wedges in a tuning-fork/fiber probe distance sensor.
abstract: We report on a new method of achieving and optimizing a high Q factor in a near-field scanning optical microscope (NSOM) by introducing two nodal wedges to a tuning-fork/fiber probe distance sensor and by selecting a vibrational mode of the dithering sensor. The effect of the nodal wedges on the dynamical properties of the sensor is theoretically analyzed and experimentally confirmed. The optimization achieved by the proposed method is understood from the vibration isolation and the subsequent formation of a local vibration cavity. The optimal condition is found to be less susceptible to the variation of the fiber tip length. This method allows effective NSOM measurement of samples placed even in aqueous solution.
authors.affiliation: Department of Information and Communication Engineering, INHA University, Incheon 402-751, South Korea.
authors.forename: Kyoung-Duck
authors.initials: KD
authors.lastname: Park
authors.forename: Dae-Chan
authors.initials: DC
authors.lastname: Kim
authors.forename: Beom-Hoan
authors.initials: BH
authors.lastname: O
authors.forename: Se-Geun
authors.initials: SG
authors.lastname: Park
authors.forename: El-Hang
authors.initials: el-H
authors.lastname: Lee
authors.forename: Seung Gol
authors.initials: SG
authors.lastname: Lee