High fidelity configuration for two-photon SLM microscopy
A method for displaying a modified phase mask on a spatial light modulator (SLM), including: modifying, by a processor, a phase mask by combining the phase mask with a virtual lens pattern, the virtual lens pattern having a focal length; displaying, by the SLM in communication with the processor, the modified phase mask on the SLM; and projecting, by a light source in communication with the processor, the light source through the SLM to form an intensity pattern at a distance from the SLM corresponding to the focal length of the virtual lens pattern, the intensity pattern being based on the phase mask.
1. A method for displaying a modified phase mask on a spatial light modulator (SLM), comprising:
modifying, by a processor, a phase mask by combining the phase mask with a virtual lens pattern,
the virtual lens pattern having a focal length;
displaying, by the SLM in communication with the processor, the modified phase mask on the SLM; and
projecting, by a light source in communication with the processor, the light source through the SLM to form an intensity pattern at a first distance from the SLM corresponding to the focal length of the virtual lens pattern,
the intensity pattern being based on the phase mask, and
zeroth-order light emitted from the SLM being focused at a second distance from the SLM different from the first distance.
2. The method of claim 1 , wherein projecting the light source further comprises:
projecting the light source through the SLM toward a lens in an output path of the SLM, wherein the intensity pattern is formed at a back focal plane of the lens.
3. The method of claim 2 , wherein the virtual lens pattern comprises a Fresnel lens pattern, and
wherein modifying the phase mask further comprises:
modifying the phase mask by combining the phase mask with the Fresnel lens pattern.
4. The method of claim 3 , wherein combining the phase mask with the Fresnel lens pattern further comprises:
generating a modular sum of the phase mask and the Fresnel lens pattern.
5. The method of claim 4 , wherein generating the modular sum further comprises:
generating the modular sum using a modulus of 2 rr.
6. The method of claim 5 , further comprising:
blocking the zeroth-order light by locating a spatial filter at a focal plane of unmodulated light located at the second distance from the SLM.
7. The method of claim 6 , wherein blocking the zeroth-order light by locating the spatial filter further comprises:
blocking the zeroth-order light by locating the spatial filter on an optical axis of the lens.
8. The method of claim 1 , wherein the light source comprises a laser.
9. The method of claim 8 , wherein the laser comprises an infrared laser.
10. An apparatus for displaying a modified phase mask on a spatial light modulator (SLM), comprising:
a processor in communication with the SLM and a light source,
a memory in communication with the processor having stored thereon a set of instructions which, when executed by the processor, cause the processor to:
modify a phase mask by combining the phase mask with a virtual lens pattern, the virtual lens pattern having a focal length,
display the modified phase mask on the SLM, and
project the light source through the SLM to form an intensity pattern at a first distance from the SLM corresponding to the focal length of the virtual lens pattern.
the intensity pattern being based on the phase mask, and
zeroth-order light emitted from the SLM being focused at a second distance from the SLM different from the first distance.
11. The apparatus of claim 10 , further comprising a lens in an output path of the SLM,
wherein the processor, when projecting the light source, is further caused by the instructions to:
project the light source through the SLM toward the lens, wherein the intensity pattern is formed at a back focal plane of the lens.
12. The apparatus of claim 11 , wherein the virtual lens pattern comprises a Fresnel lens pattern, and
wherein the processor, when modifying the phase mask, is further caused by the instructions to:
modify the phase mask by combining the phase mask with the Fresnel lens pattern.
13. The apparatus of claim 12 , wherein the processor, when combining the phase mask with the Fresnel lens pattern, is further caused by the instructions to:
generate a modular sum of the phase mask and the Fresnel lens pattern.
14. The apparatus of claim 13 , wherein the processor, when generating the modular sum, is further caused by the instructions to:
generate the modular sum using a modulus of 2π.
15. The apparatus of claim 14 , wherein the processor is further caused by the instructions to:
block the zeroth-order light by locating a spatial filter at a front focal plane of the lens.
16. The apparatus of claim 15 , wherein the processor, when blocking the zeroth- order light by locating the spatial filter, is further caused by the instructions to:
block the zeroth-order light by locating the spatial filter on an optical axis of the lens.
17. The apparatus of claim 10 , wherein the light source comprises a laser.
18. The apparatus of claim 17 , wherein the laser comprises an infrared laser.