Optical illumination system
Systems and methods are provided that combine an amplitude modulation SLM with a phase modulating SLM in the same optical illumination system. The combination of the amplitude modulation SLM and the phase modulation SLM allows the optical illumination to compensate for the limitations of amplitude modulation SLM by using phase modulating SLM and conversely to compensate for the limitations of phase modulation SLM by using amplitude modulating SLM.
1. A two photon excitation optical illumination system having an optical axis comprising:
an image plane perpendicular to an optical axis;
an amplitude modulating spatial light modulator positioned substantially adjacent to a conjugate plane of the image plane and configured to direct an optical signal to the image plane;
an aperture plane perpendicular to the optical axis;
a phase modulating spatial light modulator positioned in a conjugate plane of the aperture plane and configured to direct an optical signal to the amplitude modulating spatial light modulator;
a coherence light source optically coupled with the phase modulating spatial light modulator, wherein said coherence light source is configured to illuminate at least a portion of the image plane by directing an optical signal to the phase modulating spatial light modulator, which directs said optical signal to the amplitude modulating spatial light modulator, which directs said optical signal to the image plane.
2. The system of claim 1 , wherein the coherence light source comprises a continuous wave laser.
3. The system of claim 1 , wherein the coherence light source comprises a pulsed laser.
4. The system of claim 1 , wherein the coherence light source comprises an amplified laser.
5. The system of claim 1 , further comprising a beam expander positioned in an optical path between the coherence light source and the phase modulating spatial light modulator, said beam expander configured to direct the optical signal to fill at least a portion of a surface of the phase modulating spatial light modulator.
6. The system of claim 5 , wherein said beam expander is further configured to direct the optical signal to fill substantially all of the surface of the phase modulating spatial light modulator.
7. The system of claim 1 , wherein the amplitude modulating spatial light modulator comprises a digital micromirror device.
8. The system of claim 1 , wherein the phase modulating spatial light modulator comprises a phase only spatial light modulator.
9. The system of claim 1 , wherein the angle of incidence of the optical signal to the amplitude modulating spatial light modulator is substantially 12 degrees.
10. The system of claim 1 , wherein the angle of incidence of the optical signal to the phase modulating spatial light modulator is less than or equal to 10 degrees.
11. The system of claim 1 , further comprising a first lens positioned in an optical path between the amplitude modulating spatial light modulator and an objective lens having a back aperture, wherein the first lens is configured to substantially fill the back aperture of the objective lens with the optical signal.
12. The system of claim 11 , wherein the first lens is positioned in the optical path equidistant between the conjugate image plane substantially adjacent to the amplitude modulating spatial light modulator and the back aperture of the objective lens.
13. The system of claim 12 , wherein a first distance between the first lens and the conjugate image plane substantially adjacent to the amplitude modulating spatial light modulator and a second distance between the first lens and the back aperture of the objective lens are each equal to the focal length of the first lens.
14. The system of claim 1 , further comprising a second lens positioned in an optical path between the phase modulating spatial light modulator and the conjugate image plane substantially adjacent to the amplitude modulating spatial light modulator, wherein the second lens is configured to position the phase modulating spatial light modulator in a conjugate image plane of the aperture plane.
15. The system of claim 14 , wherein the second lens is positioned in the optical path equidistant between the phase modulating spatial light modulator and the conjugate image plane substantially adjacent to the amplitude modulating spatial light modulator.
16. The system of claim 15 , wherein a first distance between the second lens and the phase modulating spatial light modulator and a second distance between the second lens and the conjugate image plane substantially adjacent to the amplitude modulating spatial light modulator are each equal to the focal length of the second lens.
17. The system of claim 1 , further comprising an optical relay positioned in an optical path between the amplitude modulating spatial light modulator and an objective lens.
18. The system of claim 1 , further comprising a first lens and a second positioned in an optical path between the phase modulating spatial light modulator and the amplitude modulating spatial light modulator and further comprising a phase filter positioned in the optical path between said first lens and said second lens.
19. The system of claim 1 , further comprising a temporal focusing grating positioned in a conjugate plane of the image plane and configured to compress the optical signal from the amplitude modulating spatial light modulator for temporal focusing and direct the temporally focused optical signal to the image plane.
20. The system of claim 1 , further comprising:
a plurality of amplitude modulating spatial light modulators each positioned in a conjugate plane of the image plane and configured to direct an optical signal to the image plane;
a plurality of phase modulating spatial light modulators each positioned in a conjugate plane of the aperture plane and configured to direct an optical signal to a respective one of the amplitude modulating spatial light modulators;
a plurality of coherence light sources each optically coupled with a respective one of the phase modulating spatial light modulators, wherein said coherence light sources are each configured to illuminate at least a portion of the image plane by directing an optical signal to a respective one of the phase modulating spatial light modulators, each of which in turn directs said optical signal to a respective one of the amplitude modulating spatial light modulators, each of which in turn directs said optical signal to a merged optical path for delivery to the image plane.
21. The system of claim 1 , wherein the optical signal directed to the image plane by the amplitude modulating spatial light modulator comprises a three dimensional pattern of laser light intensity.
22. The system of claim 21 , wherein said three dimensional pattern of laser light intensity is configured to trigger photo-crosslinking of materials to lithographically produce a structure of a predetermined three dimensional pattern.
23. The system of claim 22 , wherein the photo-crosslinked material comprises a zincromium-silicon material.
24. The system of claim 22 , wherein the photo-crosslinked material comprises a porous hydrogel.
25. The system of claim 24 , wherein the porous hydrogel comprises an extracellular matrix.