Polarized Fringe Pattern Generation By A Digital Mirror Device Used For Structure Illumination Microscopy

Digital micromirror device(DMD)is an electrical addressing type spatial light modulator(SLM),which is designed based on microelectronic mechanical system and CMOS electronics.A DMD has the advantages of programmable and switching rapidly and cost effective,and is mainly used to project digital images or video.intensity and phase of vector beams can be controlled by the binary hologram encoding method using a single DMD.Furthermore,intensity,phase and polarization of vector beams can be rapidly switch controlled by the binary hologram encoding method and spatial filter and half-wave plate and beam displacer using a single DMD.Structured illumination microscopy(SIM)is one of wide-field super-resolution microscopy.The quality of the SIM image is heavily dependent on the contrast of the sinusoidal fringe illumination patterns.The higher fringe contrast,the better quality of the reconstruction super-resolution image.For maximal interference contrast,precise polarization control to maintain s-polarization for different fringe orientations is critical.Due to recover information from an area twice the size of the normally observable region,the fringe needs to orientate in three different directions.In this paper we research how to generate the highest fringe contrast illumination for SIM by using a single DMD.the main contributions of this thesis include:1.We study mechanism of DMD thoroughly,and describe all of the micro-mirrors of DMD which are considered to be idle state or ON state by using mathematical method.We study algorithm for generating binary hologram Which is Lee holography method,and give explain why Lee holography method which record amplitude information and phase information in detail.And we also give a detailed account why intensity,phase and polarization of vector beams can be rapidly switch controlled with the binary hologram encoding method and spatial filter and half-wave plate and beam displacer using a single DMD.We study the principle of SIM technology profoundly and find out the relation why the polarization state of fringe affects the fringe contrast.Furthermore,we expound the method of how to produce the highest fringe contrast illumination for SIM by using the ferroelectric liquid crystals(FLC)and two custom FLC switchable phase retarders.2.We present binary hologram patterns which are Ince-Gaussian(IG)beam and fringes for SIM according to Lee method by Mtalab.and we also present the intensity pattern and phase pattern which the binary hologram patterns restore by Matlab.3.To perform the shaping experiment,we design an optical setup which combines the amplitude DMD and the Lee method.And we discuss which devices are needed for building the DMD in set-up,and describe the order of the dimensional adjustment of DMD for beam alignment.Finally,experimental results are presented and analyzed.In summary,if a single DMD was used to produce the highest fringe contrast illumination for SIM.what need to change in lab system is only the pattern load into DMD,other equipment do not need change,at the same time,we can boost the switching speed of polarized fringe at different direction.