Compensation of chromatic aberration in multiwavelength digital holographic investigation of microstructures

We demonstrate that refractive index profile of microstructure could be correctly recovered in multiwavelenght digital holographic microscope when chromatic aberration is taken into account. The chromatic aberration introduced by the optical imaging components can be can be numerically compensated in the reconstruction process. The compensation approach requires the control of the reconstructed pixel size in the image plane if a Fresnel Transformation Method is adopted to take into account the different wavelengths used to investigate the samples. Description of the method and several examples of application will be discussed.