Improved axial position detection in optical tweezers measurements

被引：60

作者：

Dreyer, JK ^{[1
]}

Berg-Sorensen, K ^{[1
]}

Oddershede, L ^{[1
]}

机构：

[1] Niels Bohr Inst, DK-2100 Copenhagen, Denmark

来源：

APPLIED OPTICS | 2004年 / 43卷 / 10期

关键词：

D O I：

10.1364/AO.43.001991

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

We investigate the axial position detection of a trapped microsphere in an optical trap by using a quadrant photodiode. By replacing the photodiode with a CCD camera, we obtain detailed information on the light scattered by the microsphere. The correlation of the interference pattern with the axial position displays complex behavior with regions of positive and negative interference. By analyzing the scattered light intensity as a function of the axial position of the trapped sphere, we propose a simple method to increase the sensitivity and control the linear range of axial position detection. (C) 2004 Optical Society of America.

引用

页码：1991 / 1995

页数：5

共 14 条

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BERGSORENSEN K, IN PRESS REV SCI INS

[2] Direct measurement of static and dynamic forces between a colloidal particle and a flat surface using a single-beam gradient optical trap and evanescent wave light scattering [J].