Microscopic viscosity measurement using orbital rotation in dual-beam fiber-optic trap with transverse offset

Abstract

We presented an optical system that could measure the viscosity coefficient of liquid in a micro-area. The orbital rotation of a polystyrene microsphere was realized by a dual-beam fiber-optic trap with a transverse offset. The rotation rate increased with the viscosity coefficient of the environmental medium. On this basis, the viscosity coefficients of ethanol solutions with different concentrations were measured successfully. The volume of solution samples was less than 1 μL. This provides a basis for the viscosity measurement of rare liquid or enchylema, which is of great significance for biological applications such as cell characteristics and reaction dynamics. © The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

Dynamic analysis of microparticle behavior in quad-beam optic-fiber optical tweezers

“…Therefore, we attempt to research on optic-fiber array leading to particle rotation or enrichment through optical radiation pressure. Moreover, this approach based on dynamic simulation offers a detailed theoretical perspective supporting experimental configuration and observation [7,12,16]. In this way, the numerical model has been built to study the optic-fiber array with a certain offset distance.…”

“…In this case, the structure of misalignment related to dual-beam optic-fibers, generating spin and orbital rotation, is more convenient than special optical field, for example circularly polarized light [8,9], Hermite-Gaussian [10], and Bessel beam [11]. Afterward, Pei and Chen [12] continued to utilize this approach in the measurement of viscosity coefficient. In addition, Li et al [13] pointed out that different optic-fiber misalignment, optical power, and optic-fiber separation could exhibit three dynamic behaviors.…”