Showing papers by "Min Gu published in 1997"
TL;DR: In this paper, a commercial high numerical-aperture microscope objective is designed in terms of the sine condition which is needed for two-dimensional space-invariant imaging.
Abstract: A commercial high numerical-aperture microscope objective is designed in terms of the sine condition which is needed for two-dimensional space-invariant imaging. The axial trapping efficiency generated by an objective obeying the sine condition is found to be approximately up to 50% smaller than the prediction for an objective obeying the tangent condition which has been currently used in the ray optics theory for trapping force calculations. Our result is in good agreement with the measured value of the trapping efficiency.
29 citations
20 citations
10 Apr 1997
TL;DR: In this article, an enhanced evanescent wave can be obtained at the surface of a multilayer thin-film coating system due to the optical tunneling effect, which can improve the illumination power by several orders of magnitude in near-field microscopy.
Abstract: Near-field microscopy usually uses an evanescent wave as an illumination source on a sample. An enhanced evanescent wave can be obtained at the surface of a multilayer thin-film coating system due to the optical tunneling effect. It can improve the illumination power by several orders of magnitude in near-field microscopy. The enhancement of an evanescent wave is related to the thickness and refractive indices of the thin film layers as well as the incident angle and wavelength of the illumination source. In this paper, optimization of these parameters is studied in detail under resonance conditions, and some experimental results also are presented.
1 citations