System, apparatus and method for using birefringent lenses to create holograms from received electromagnetic radiation
The inventors have discovered a method to improve image quality in holography and, for the first time, utilize lenses made from birefringent materials to advantageously split an incoming beam of either coherent or incoherent light into two coincident beams with different focal lengths that interfere with one another and thus create holograms free of electro-optical or pixelated devices. This discovery has many advantages over current methods to create holograms in which many components, including multiple lenses, other electro-optical devices, and/or beam paths are necessary to create holograms. The current invention provides a purely optical holographic process which has better performance and holographic simplicity, in addition to being able to miniaturize holographic processes more than is currently possible in state of the art holography systems.
1. An optical apparatus, comprising:
a plurality of lenses including at least one lens incorporating anisotropic electromagnetic properties, and at least one compensating optical element incorporating anisotropic electromagnetic properties configured to correct optical path differences, wherein the plurality of lenses are configured to:
receive electromagnetic radiation from an object, wherein the electromagnetic radiation is incoherent light;
transform, by refraction using the at least one lens incorporating anisotropic electromagnetic properties without electrical control of the at least one lens, the received electromagnetic radiation to generate two or more differentially modulated electromagnetic waves propagating in a common path;
correct, using the at least one compensating optical element, one or more undesired optical path differences between the differentially modulated electromagnetic waves; and
provide for the differentially modulated electromagnetic waves, after the correcting, to create electromagnetic interference.
2. The optical apparatus according to claim 1 , wherein the at least one lens incorporating anisotropic electromagnetic properties includes a birefringent lens.
3. The optical apparatus according to claim 2 , wherein another lens is configured to modify the focal length of each of the differentially modulated electromagnetic waves exiting the birefringent lens.
4. The optical apparatus according to claim 3 , wherein a spacing factor of the differentially modulated electromagnetic waves is changeable according to a focal length of said another lens.
5. The optical apparatus according to claim 4 , wherein said another lens is a glass lens.
6. The optical apparatus according to claim 2 , wherein the birefringent lens comprises alpha or beta barium borate materials.
7. The optical apparatus according to claim 2 , wherein the birefringent lens comprises liquid crystal material encased in flat or positively or negatively curved birefringent materials.
8. The optical apparatus according to claim 2 , wherein the birefringent lens comprises liquid crystal material encased in flat or positively or negatively curved non-birefringent materials.
9. The optical apparatus according to claim 1 , wherein the electromagnetic interference forms a hologram representing the object.
10. The optical apparatus according to claim 9 , wherein the hologram is a Fresnel Incoherent Correlation Holography (FINCH) hologram.
11. The optical apparatus according to claim 9 , wherein the hologram is any of a Fresnel hologram, a Fourier hologram, a Fresnel Incoherent Correlation Holography (FINCH) hologram, or an off-axis hologram.
12. The optical apparatus according to claim 1 , wherein the received electromagnetic radiation is from a microscope.
13. The optical apparatus according to claim 1 , further comprising a camera configured to record the interference.
14. The optical apparatus according to claim 1 , the apparatus being further configured to use the electromagnetic interference as an excitation pattern in scanning holography.
15. The optical apparatus according to claim 1 , the apparatus being further configured to use the electromagnetic interference in an excitation source in a Structured Illumination (SIM) imaging system.
16. The optical apparatus according to claim 1 , wherein the optical apparatus is contained within a microscope objective lens.
17. The optical apparatus according to claim 1 , wherein the at least one compensating optical element is configured to minimize optical path differences between the differentially modulated electromagnetic waves relative to the coherence length of the electromagnetic radiation.
18. The optical apparatus according to claim 1 , wherein the at least one compensating optical element is a birefringent compensating optic oriented with its anisotropic electromagnetic properties rotated relative to those of the at least one lens by a specific amount calibrated to achieve a desired level of correction.
19. A method comprising:
receiving electromagnetic radiation from an object, wherein the electromagnetic radiation is incoherent light;
transforming, by refraction using at least one lens incorporating anisotropic electromagnetic properties without electrical control of the at least one lens, the received electromagnetic radiation to generate two or more differentially modulated electromagnetic waves propagating in a common path;
correcting, using at least one compensating optical element incorporating anisotropic electromagnetic properties configured to correct optical path differences, one or more undesired optical path differences between the differentially modulated electromagnetic waves; and
providing for the differentially modulated electromagnetic waves, after the correcting, to create electromagnetic interference.
20. The method according to claim 19 , wherein the at least one lens incorporating anisotropic electromagnetic properties includes a birefringent lens.