A method for determining both multiple refractive indices and 3D substructure of a binucleate cell

• The maximum entropy reconstruction method (MER) cannot work on a multimedium sample.
• The optimized method of phase gradient is introduced to overcome the vague boundary.
• We reconstructed the 3D substructure of a binucleate cell with the improved MER.
• Some phase imaging experiments of neutrophils are performed.

A method is proposed in this paper that can determinate both multiple refractive indices and substructure of a binucleate cell. The method can overcome the shortcoming of the maximum entropy reconstruction method (MER) that is invalid for a multimedium sample. With the optimized algorithm using phase gradients and the relevant parameters, a well-bedded refractive index distribution can be obtained, and then the 3D substructure reconstruction can be realized for a multimedium sample. We demonstrated this method by the simulation of a binucleate cell model and some phase imaging experiments of neutrophils. Results show that the method is valid, and is very suitable for the 3D substructure imaging of cells with simple structure.