Study Of Microsphere Lens Manipulating System For Optical Super-Resolution Imaging

Optical microscopy plays an irreplaceable role in research and development of science.However,due to the existence of diffraction limit,the resolution limit of traditional optical microscopy is only half of the wavelength of illumination light.With the development of science and technology,a lots of super-resolution imaging technologies and equipment had been developed.Among them,using microsphere lens to achieve optical super-resolution imaging has the advantages of low equipment cost,in-situ observation and so on,so this simple and effective super-resolution imaging method had attracted wide attention of the scientific community.However,it is difficult to realize super-resolution imaging by using microsphere lens in a more convenient way,which is also the reason why the technology of super-resolution imaging of microsphere lens is hard to popularize.In this paper,a multi-dimensional automatic operation system for super-resolution optical imaging of microsphere lenses was proposed and designed.The precise operation of microsphere lenses was realized by using the probe as the operating tool.Using this operating system,optical super-resolution imaging of samples such as alphabet pattern and stripes of Blu-ray disc were achieved through microsphere lens by non-contact scanning,which broke the limitation of imaging range of traditional method.The imaging mode of sample-adhered observation which was able to break the limitation of manipulating space of traditional method was proposed.The sample adhered to the bottom of microsphere lens can be manipulated by other tungsten probes,so the functional limitation that microsphere lens only can be used for observation was broken.The experimental results show that this manipulating method had important practical significance for the application and development of the super-resolution imaging theory of microsphere lenses.The main contents of this paper are listed as follows:(1)According to the imaging principle of microsphere lens,the feasibility of the operation scheme for microsphere lens was analyzed theoretically.The feasibility of non-contact super-resolution imaging by microsphere lens was demonstrated.The improvement of imaging effect by liquid medium was proved.Considering the research purpose,imaging characteristics and imaging effect,the BTG was selected as the material of microsphere lens,and the full immersion method was used as the immersion method for microsphere lens.Finally,the optical simulation has been performed to demonstrate that the influence of probe on super-resolution image was negligible,so that the feasibility of the method of manipulating microsphere lens by probe was proved.(2)Aiming at the operation mode of probe-adhered microsphere lens,a multi-dimensional automated experimental operating system was designed and built.Kinematics and dynamics analysis of the motion system were performed for manipulating tungsten probe.According to the mechanical analysis of microsphere lens,it is concluded that the moving speed can’t exceed 10.3 m/s,and the acceleration can’t exceed 4.68 m/s2.Then,an experimental manipulating system was established by equipping the motion system with an appropriate optical imaging system and a cooperative operating system.Considering stiffness,adhesion stability,imaging effect,ST tungsten probe was selected as the probe type used in the experimental operation.(3)The practicability and flexibility of the microsphere lens multi-dimensional automatic operating system were verified by super-resolution observation experiments of different samples.Super-resolution imaging of stripes of Blu-ray disc could be achieved through microsphere lens,when the microsphere lens was adhered to the tip of tungsten probe.Through experiments and analysis,it was concluded that when photonic nanojet was inside the sample,relatively clear images could be achieved,which proved the feasibility of non-contact super-resolution imaging of microsphere lens.By scanning the microsphere over the sample surface and stitching the recorded images,the super-resolution image of large continuous area was achieved.The capability of the manipulating system for three-dimensional scanning super-resolution imaging was proved by scanning observing the stripes of the tilted Blu-ray disc by manipulating the microsphere lens.Super-resolution observation of complex samples such as alphabet pattern and magnified microscopic observation of biological samples such as rat liver slices and yeast cells were realized by microsphere lens,which verified the versatility of the manipulating method.The imaging mode of sample-adhered observation which was able to break the limitation of manipulating space of traditional method without affecting the imaging quality was proposed.Moreover,the adhered yeast cells could be moved,removed and scanned by other probes,so that the simple micro-nano manipulations could be performed on the adhered-samples when the samples were observed by micro lens.Therefore,the functional limitation that microsphere lens only can be used for observation was broken.