Real-time in situ calibration of an optically trapped probing system.
Appl Opt
; 48(25): 4832-41, 2009 Sep 01.
Article
em En
| MEDLINE
| ID: mdl-19724324
ABSTRACT
We present real-time in situ calibration of an optically trapped probing system. In the probing system, a micro/nanobead is stably trapped around the minimum of the field potential to serve as the measurement probe, whereas the random thermal force tends to destabilize it and causes Brownian motion around the equilibrium. The weighted recursive least-squares algorithm is applied to recursively update the system's parameters, such as the state transition coefficient, and to estimate specific system response and the unknown variance of the Gaussian white noise in real time according to the probe's motion. The real-time recursive algorithm was first applied to real-time calibration of measurement sensitivity and trapping stiffness for the case that the local temperature and the damping coefficient of the probe are known. It was then applied to estimate the probe's local temperature in real time. Two experiments were designed to illustrate the applicability of the real-time calibration method. The experimental results show that the recursive algorithm is able to real-time calibrate the trapping stiffness of the probing system and the measurement sensitivity of the back-focal-plane interferometry employed for position measurement. The experimental results also show that the method can estimate the probe's local temperature in real time.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Algoritmos
/
Técnicas de Sonda Molecular
/
Pinças Ópticas
Tipo de estudo:
Prognostic_studies
País/Região como assunto:
America do norte
Idioma:
En
Revista:
Appl Opt
Ano de publicação:
2009
Tipo de documento:
Article
País de afiliação:
Estados Unidos