System, method and apparatus for phase-coded multi-plane microscopy
A volume holographic imaging system enables the projection of a two-dimensional (2D) slice of a four-dimensional (4D) object. The 4D source object is illuminated to emit or scatter an optical field. A holographic element having one or more recorded holograms receives and diffracts the optical field into a diffracted plane beam. A phase mask is encoded in one or more multiplexed holographic gratings of the holographic element using a spatial filter. A collector lens focuses the diffracted plane beam to a 2D slice of the 4D probing source object. The focused 2D slice is projected onto a 2D imaging plane. The holographic element may have multiple multiplexed holograms that are arranged to diffract light from a corresponding slice of the 4D probing source object to a non-overlapping region of the detector.
1. A volume imaging system for imaging a source object comprising:
a transmissive holographic element having one or more multiplexed holographic gratings for imaging one or more optical fields of a source object, each of the multiplexed holographic gratings having a phase mask recorded therein, and each of the multiplexed holographic gratings configured to receive and selectively diffract an optical field emitted or scattered from a respective two-dimensional slice of the source object into a corresponding diffracted plane beam; and
collector optics configured to focus each diffracted plane beam to form a phase contrast image of the corresponding two-dimensional slice of the source object at an imaging plane.
2. The volume imaging system of claim 1 , wherein the transmissive holographic element diffracts the optical field emitted or scattered from the two-dimensional slices of the source object based on one or more Bragg properties.
3. The volume imaging system of claim 1 , wherein the volume imaging system is configured to simultaneously diffract an optical field from each of the two-dimensional slices of the source object to a non-overlapping region of the imaging plane.
4. The volume imaging system of claim 1 , wherein the source object is defined in four dimensional space and real time.
5. The volume imaging system of claim 1 , wherein the recorded phase mask for at least one of the multiplexed holographic gratings encodes an image of a Zernike filter.
6. The volume imaging system of claim 1 , wherein the recorded phase mask for at least one of the multiplexed holographic gratings encodes an image of a knife edge filter.
7. The volume imaging system of claim 1 , further comprising a filter whose image is recorded as the phase mask during formation of each of the multiplexed holographic gratings in a volume recording medium to form the transmissive holographic element, the filter being disposed in axial relation to the transmissive holographic element.
8. The volume imaging system of claim 7 , further comprising a 4-f telecentric relay system interposed between the filter and the transmissive holographic element.
9. The volume imaging system of claim 1 , wherein the one or more multiplexed holographic gratings are recorded in phenanthrenquinone doped poly methyl methacrylate.
10. The volume imaging system of claim 1 , wherein the phase mask of each multiplexed holographic grating eliminates the DC component in the spatial frequency domain of the corresponding phase-contrast image of the two-dimensional slice of the source object.
11. The volume imaging system of claim 1 , further comprising an objective lens positioned between the source object and the transmissive holographic element and configured to receive and collimate electromagnetic radiation emitted or scattered from the source object.
12. The volume imaging system of claim 11 , wherein the volume imaging system is a microscope.