Design And Method Study Of Linear Optical Tweezer Microscopic Imaging System

Since Ashkin invented the single-beam gradient force trap in 1986,optical tweezers have shown its great potential as a tool to study microscopic particles.Through decades of continuous research by researchers,optical tweezers have been continuously improved and successfully applied to various fields from nano to micron.It is a hot spot to produce optical tweezers by using all kinds of new beams.In this paper,a linear optical tweezers is made by using linear laser,which can be switched between single and double wires and its geometric size can be adjusted.Focusing on the linear optical tweezers technology,this paper introduces and studies the following aspects respectively:1.Introduce the characteristics of Gaussian beam,and analyze the shaping effect of single cylindrical lens and vertically spaced cylindrical lens on the beam;The restraining effect of collimating beam expanding system on beam is analyzed,which provides theoretical basis for the design,simulation and construction of linear optical tweezers system.2.Through Zemax optical simulation software design,discuss and compare the advantages and disadvantages of several laser shaping schemes,such as single-column lens,orthogonal distance double-column lens and Powell prism,in this paper,orthogonal distance doublecolumn lens and collimating beam expanding system are optimized to design a linear laser shaping system with adjustable aspect ratio.Using TEM10 mode laser as light source,linear optical tweezers with adjustable aspect ratio and single and double line switching are obtained through beam shaping system,collimating beam expanding system and microscope objective.3.Using high-order mode laser to build a single-line and double-line switching linear optical tweezers microscopic imaging experimental system,which can capture and arrange polystyrene microspheres with different sizes;The rotating beam shaping system realizes the single-line and double-line switching of the linear optical tweezers,and then can rotate and control the microspheres captured by the linear optical tweezers.According to the experimental results,the capture force of single-wire and double-wire optical tweezers is compared.4.Based on the compatibility of the linear optical tweezers with various micro-imaging technologies,a rotating speckle micro-imaging system based on linear optical tweezers and a rotating optical plate micro-imaging system based on linear optical tweezers are constructed respectively.The linear tweezers were used to rotate the captured fluorescent microbeads to obtain scatter images of the samples and to image the microbeads by light sheet chromatography,respectively.