An optical scheme of recording digital holograms of micro-objects based on high numerical aperture off-axis parabolic mirror forming a high aperture reference wave is suggested. Registration of digital holograms based on the proposed optical scheme is confirmed experimentally. Application of the proposed approach for hyperspectral holograms registration of micro-objects in incoherent light is discussed.
It is suggested to measure non-axis parabolic mirrors aberrations and try to compensate for them. For the aberration prediction the computer modeling is used. For the aberration measurement Shack-Hartmann wavefront sensor is applied. For the aberrations compensation a digital algorithm is used.
Novel method is suggested for a hyperspectral wave field holographic recording, based on asymmetrical Fourier spectrometer with a flat microobject placed in one of its arms. The output signal, which is the interference of the reference field with the field diffracted by the object, is registered by CCD. The process of recording is reduced to consecutive registration of two-dimensional interferograms by changing the optical length of the reference arm of the interferometer. One-dimensional Fourier transform of the interferogram in each pixel gives a spatial distribution of the complex amplitude for all spectral components of a hyperspectral object field. Inverse Fresnel transform of this field gives a hyperspectral object field in the object plane. Hyperspectral amplitude and average-phase profile images of standard microscope samples obtained experimentally are presented. Coloring, Fellgett’s advantage and speckle noise reduction are discussed.