Optical Microscopy Tomography Experimental System Design And Development,

Optical microtomography is the combination of computed tomography and coherence tomography.It can acquire the 3D refractive index spatial distribution of the specimen like cells,so it's widely used in the field of biology and medicine.In my thesis,we discussed it's basic principle and methods in theory and established an optical microtomography apparatus. We acquired some main results as follows.We summarized the actuality about optical microtomography internal and external at first.Then we presented a experiment system that combined conical scanning beams and horizontal scanning method instead of using parallel beams in conjunction with variable illumination angle to acquire the projections in multiple directions.Then we did some research on the physical method and reconstruction of three-dimensional phase objects.According to the theory above,we put forward a project and fabricated a optical microtomography system.It can capture projections of cells with object lens of different kinds of magnifications such as 4×,10×,16×,25×,40×and 60×.Its resolution can achieve 0.08μm.We have done some calculation about the projections which captured by us.We did some experiment on onion cell by our system,and acquired its microscopy images and micro coherence images.By making use of Fourier transform and phase unwrapping method,we retrieved absolute phase of onion. These provide a foundation for the following reconstruction of specimen.In addition,we discussed some other factors which can affect our experiment result such as mode jumping,defocus of micro object lens and error of the optical element.