Apparatus and method for foci array scanning through an adjusting refractive medium
A method and apparatus for performing foci array scanning using at least one adjustable or tilting medium is disclosed. The medium can be controllably tilted in order to translate a beam of electromagnetic radiation perpendicularly to its propagation, and upon exiting the medium, will propagate in the original, incoming direction. This allows the apparatus that emits the radiation, such as a laser, to remain stationary and still scan a 2D array. Additionally, the reflected fluorescence light undergoes the opposite shift to “reverse” the scanning shift and bring the beamlets back in line with a lenselet array. So the collection fibers can remain static and collect light from different spots on the sample from during the scan.
1. An apparatus for foci array scanning, comprising:
at least one lenslet array for producing a plurality of light beams travelling in a given direction said lenslet array generating a foci array at an image plane located in a predetermined position;
a microscope architecture including a tube lens and an objective lens, said tube lens being positioned for focusing the plurality of light beams onto said objective lens which is configured to focus the light beams onto an area to be imaged in an x-y plane which is perpendicular to the given direction the light beams are travelling in, said at least one lenslet array and said microscope architecture configured such that the image plane is shared with said field lens such that said foci array is projected through the tube lens onto the area to be imaged to form a conjugate plane;
a scanning array located between said lenslet array and said microscope architecture which includes at least two refractive windows spaced from each other, each refractive window having parallel opposed surfaces and having a preselected index of refraction, wherein for a given index of refraction and a given angle of incidence of each light beam from the array of light beams on one of said opposed surfaces, each beam of light, upon exiting the other opposed surface, is translated a known amount laterally, and parallel to, each beam's direction of propagation independently of a location of contact between the array of light beams and refractive windows, said refractive windows being mounted for tilting to achieve raster scanning in the x-y plane, one of said refractive windows being mounted to translate the light beams laterally in the x-direction a first distance and the other refractive window being mounted to translate the light beams laterally in the y-direction a second distance such that tilting of the refractive windows causes deflection of the light beams in the x-y plane thereby scanning across the area to be imaged; and
wherein light beams collected from the area to be imaged through said objective lens and said field lens goes backwards through the scanning array and experience an opposite shift in the x-direction by said first distance and in the y-direction by said second distance.
2. The apparatus of claim 1 wherein the at least two refractive windows are made of one of glass, plastic or fluorite.
3. The apparatus of claim 1 wherein the array of light beams includes a plurality of parallel, distinct beams of light.
4. The apparatus of claim 1 wherein the array of light beams of light comprises laser beams.
5. The apparatus of claim 1 wherein said refractive medium is movably mounted to allow adjustment of the angle of incidence of the array of light beams between about −25 to about +25 degrees.
6. The apparatus of claim 1 wherein the refractive medium operably refracts the array of light beams onto a 2D-1D fiber array which converts a 2D signal into a 1D signal.
7. The apparatus of claim 6 wherein the 1D signal is received by a streak camera.
8. The apparatus of claim 6 wherein the 1D signal is received by a spectrograph.
9. The apparatus of claim 1 wherein the at least two refractive windows are inserted in a microscope between the tube lens and the objective.
10. The apparatus of claim 1 , wherein said at least one lenslet array is one lenslet array, and wherein the microscope architecture and the lenslet array are configured so that the light beams collected from the area imaged are directed back to the lenslet array during descanning.
11. The apparatus of claim 1 , wherein said at least one lenslet array is a first lenslet array, said apparatus including a second lenslet array and a beam splitter, said beamsplitter and said second lenslet array and being positioned with respect to each other and said scanning array such that the light beams collected from the area imaged are incident on the beam splitter after passing through said scanning array and then directed to said second lenslet array during descanning.