The Research Of Tunable Filter Based On Spatial Light Modulator

In last twenty years,tunable filters are used in more and more applications like material analysis,sample detection and identification and even astronomy,and achieving tunable wavelengths and bandwidth are concerned issues.Spatial light modulator(SLM)can modulate wide wavelengths,so tunable filters based on SLM attracts much attention.In this thesis,several common light filter devices were introduced,and a better tunable filter system was proposed,and its principle in detail explained,and designed,relative experiments data and outcome analysis provided.The design is based on spatial light coupling theory,guide input light dispersed and focused on SLM by grating and lens,which constitutes a wide wavelengths tunable filter system.In this thesis,the basic theory is given first,then every optical device's function and principle,especially two common SLM,namely Liquid Crystal on Silicon(LCoS)device and Digital Micromirror Device(DMD).LCoS and DMD can accomplish the above goals and has programmable functionality,which is convenient for experiments.Focused on SLM,the whole system was designed,and the paper analyses every optical device and ensure their parameters.The system's filtering function was well reprensented by relative experiments and through two lasers and one visible light source.Besides,the paper introduce a software programmed for experiments and the system,and explore the possible application.Of course,the system is defective in both software and hardware,which is the next goal.