Cell refractive index tomography by digital holographic microscopy

Area of Science:

• Biophysics
• Microscopy
• Optical imaging

Background:

• Accurate characterization of micro-scale biological structures is essential for understanding their function.
• Traditional imaging methods often lack the resolution or accuracy needed for detailed analysis of complex biological samples like pollen.

Purpose of the Study:

• To apply digital holographic microscopy for optical diffraction tomography of a pollen grain for the first time.
• To reconstruct the three-dimensional refractive index distribution of pollen with high precision and resolution.

Main Methods:

• Digital holographic microscopy was employed to acquire holographic data from a rotating pollen sample.
• Transmission phase images were numerically reconstructed from holograms with nanometric axial accuracy.
• The three-dimensional refractive index distribution was computed using an inverse Radon transform.

Main Results:

• The study successfully demonstrated optical diffraction tomography of a pollen grain using digital holographic microscopy.
• Nanometric axial accuracy was achieved in the reconstruction of transmission phase images.
• A precision of 0.01 for refractive index estimation and micrometer-scale spatial resolution were achieved.

Conclusions:

• Digital holographic microscopy is a viable and powerful technique for optical diffraction tomography of biological micro-structures.
• The demonstrated precision and resolution enable detailed quantitative analysis of pollen's internal structure.
• This method opens new avenues for the investigation of micro-scale biological samples.