Study On The Operation Of Optically-induced Dielectrophoresis With Touch Control

Optically-induced dielectrophoresis technology is a recently developed microscale manipulating technology,which can be used to assemble,separation or transport the micro/nano objects in ODEP chip by the light pattern operation.ODEP operation can be applied in many fields,but its operation interface and observation interface are usually separated,which is the problem of existing ODEP operation.And the problem leads to the operation in the two interfaces cannot be executed synchronously,which decreases its visualization and efficiency.Aiming at this problem,this paper proposes a light induced dielectrophoresis method with touch control.Adopting a new managed code programming model based on.Net Framework.The structure light projection module,video monitoring module,motion control module of the integrated touch interface are developed.With the same touch interface operators can not only observe the samples,but also operate the sample synchronously by touch operation.At present,although there are excellent ODEP operating techniques in the world,there is no touch ODEP operating method.This method of operation greatly improves the intuitiveness and efficiency of ODEP operations.The touch-controlled ODEP system successfully achieved the touch capture of silica particles,transport.Experimental results show that the success rate of the silicon dioxide moving is different under different moving speeds of the photoelectrode,and then the relationship between the moving speed of the photoelectrode and the success rate of the silicon dioxide being moved is obtained.At the same time,it also realizes the label-free purification and separation of different biological cells,the rapid assembly of microstructures and the deposition and processing of silver electrodes in silver nitrate solution,thus providing a new operation mode for ODEP micro-nano manipulation.The main work of this paper is as follows:(1)This chapter briefly explain the dielectrophoresis theoretical model,and thus extend the principle of light induced dielectrophoresis.The characteristics of the dielectrophoretic force of the microspheres in the light-induced chip were simulated and analyzed.The hardware structure of the touch-control ODEP system is designed,and the software design flow of the touch-control ODEP system and the function and connection of each function module of the software are introduced in detail.(2)Using Canny edge detection method,the edge information of the target particle is successfully detected.Firstly,Gaussian filter is used to smooth and dry the image,and then the amplitude and angle images are obtained.Finally,the maximal value of the amplitude image is suppressed.Finally,the edge information of the image is obtained through programming.(3)On the basis of obtaining the edge information of the image,the improved Hough transform is used to precisely locate the specific position of the target image acquired in the touch-control ODEP system,so that the photoelectrode image drawn in the touch-control ODEP system and the CCD Acquired images do not exactly coincide.Perfect the touch ODEP system.(4)Several experiments were conducted using the touch ODEP system.Touch capture and transport on silica particles,label-free purification and separation of different biological cells,rapid assembly of microstructures,and deposition and processing of silver electrodes in silver nitrate solution were achieved respectively.Through experiments,it is verified that the touch ODEP control method is efficient and intuitive.