Method and apparatus for correcting crosstalk and spatial resolution for multichannel imaging
View Patent ↗A multi-channel imaging system generates an ensemble of images for each field of view of an object. Each image in the ensemble is intended to contain information from only one source among a plurality of sources for the object. However, due to crosstalk, at least a portion of the signal from a first source appears in a channel intended for a second source. Because the accuracy of the correction will be degraded if the images in an ensemble are spatially misaligned with respect to one another, the spatial offset between images is determined and a correction is applied to substantially eliminate the offset. Then, a correction to the signals is determined to substantially reduce the contributions to the signal in a channel from the signals in other channels. The signal processing can be employed to process the output signals for each of a plurality of different disclosed imaging systems.
1. A method for correcting errors in a multi-channel imaging system, wherein each channel has signal information relating to an image of an object, comprising the steps of:
(a) directing light from the object along a collection path;
(b) dispersing the light that is traveling along the collection path into a plurality of light beams;
(c) focusing each of the light beams to produce respective images from the light beams;
(d) providing at least one detector disposed to receive the respective images and in response, generating an output signal corresponding to each image;
(e) correcting spatial misalignment of the images received by said at least one detector to within sub-pixel resolution, so that all output signals generated by the at least one detector are substantially spatially aligned; and
(f) substantially reducing crosstalk contributions between each output signal.
2. A multi-channel imaging system including error correction capabilities, wherein each channel has signal information relating to an image of an object, comprising:
(a) a light directing element disposed so that light traveling from the object is directed along a collection path by the light directing element;
(b) a dispersing component that receives the light traveling along the collection path and disperses the light into a plurality of light beams;
(c) at least one detector;
(d) an imaging lens that focuses each of the plurality of light beams on said at least one detector, producing a respective image corresponding to a different one of the plurality of light beams, said at least one detector providing an output signal for each respective image;
(e) means for correcting spatial misalignment of the images received by said at least one detector to within sub-pixel resolution, so that all output signals provided by said at least one detector are substantially spatially aligned; and
(f) means for substantially reducing crosstalk contributions between each output signal.
3. A method for correcting errors in a multi-channel imaging system, wherein each channel is intended to contain signal information relating to an image of an object, comprising the steps of:
(a) directing light from the object along a collection path;
(b) dispersing the light that is traveling along the collection path into a plurality of light beams;
(c) focusing each of the light beams to produce respective images for the light beams;
(d) providing at least one detector disposed to receive the respective images and in response, generating an output signal corresponding to each image;
(e) correcting spatial misalignment of the images received by said at least one detector, so that all output signals generated by the at least one detector are substantially spatially aligned; and
(f) substantially reducing crosstalk contributions between each output signal.
4. The method of claim 3 , wherein the step of correcting spatial misalignment comprises the steps of:
(a) determining a spatial offset between an image currently being processed and a reference image; and
(b) applying a correction factor to the output signal of the image currently being processed, wherein the correction factor is determined so as to substantially eliminate the spatial offset.
5. The method of claim 4 , wherein the output signal includes image data for the image currently being processed and reference image data for the reference image, and wherein the step of applying a correction factor so as to substantially eliminate the spatial offset comprises the steps of:
(a) spatially adjusting image data in the output signal so that the image data in the output signal is aligned with the reference image data to the nearest pixel; and
(b) reconstructing the output signal by interpolating a remainder of the spatial offset to a fraction of a pixel, to further reduce the spatial offset in the output signal for the image currently being processed.
6. The method of claim 3 , wherein each output signal is represented by a linear equation, and wherein the step of substantially reducing crosstalk contributions to the output signal comprises the step of solving a set of linear equations for the output signals.
7. The method of claim 6 , wherein the step of solving the set of linear equations comprises the step of solving the set of linear equations for each pixel in the image that produces the output signal.
8. The method of claim 7 , wherein the step of solving the set of linear equations further comprises the step of applying a singular value decomposition to a matrix form of the set of linear equations.
9. A multi-channel imaging system including error correction capabilities, wherein each channel is configured to provide signal information relating to an image of an object, comprising:
(a) a light directing element disposed so that light traveling from the object is directed along a collection path by the light directing element;
(b) a dispersing component that receives the light traveling along the collection path and disperses the light into a plurality of light beams;
(c) at least one detector;
(d) an imaging lens that focuses each of the plurality of light beams on said at least one detector, producing a respective image corresponding to a different one of the plurality of light beams, said at least one detector providing an output signal for each respective image;
(e) means for correcting spatial misalignment of the images received by said at least one detector, so that all of the output signals are substantially spatially aligned; and
(f) means for substantially reducing crosstalk contributions between each output signal.
10. The multi-channel imaging system of claim 9 , wherein the means for correcting and the means for substantially reducing are implemented with a processing component.
11. The multi-channel imaging system of claim 10 , wherein said processing component comprises an oscilloscope.
12. The multi-channel imaging system of claim 10 , wherein said processing component comprises a programmable computing device.
13. The multi-channel imaging system of claim 10 , wherein said processing component comprises an application specific integrated circuit.
14. The multi-channel imaging system of claim 9 , wherein each detector comprises a pixilated detector.
15. The multi-channel imaging system of claim 9 , further comprising a display electrically coupled to the means for correcting and to the means for substantially reducing, said display producing an image in response to each output signal.
16. The multi-channel imaging system of claim 9 , wherein said means for correcting implements the following functions:
(a) determining a spatial offset between an image currently being processed and a reference image; and
(b) applying a correction factor to the output signal of the image currently being processed to substantially eliminate the spatial offset.
17. The multi-channel imaging system of claim 16 , wherein the function of applying a correction factor so as to substantially eliminate the spatial offset is implemented by:
(a) spatially adjusting image data in the output signal so that the image data in the output signal is aligned with the reference image data to the nearest pixel; and
(b) reconstructing the output signal by interpolating a remainder of the spatial offset to a fraction of a pixel, to further reduce the spatial offset in the output signal for the image currently being processed.
18. The multi-channel imaging system of claim 9 , wherein each output signal is represented by a linear equation, and wherein said means for substantially reducing crosstalk contributions between each output signal is configured to solve a set of linear equations for the output signals.
19. The multi-channel imaging system of claim 18 , wherein said means for substantially reducing crosstalk contributions between each output signal is configured to solve the set of linear equations for each pixel in the image that produces the output signal.
20. The multi-channel imaging system of claim 19 , wherein said means for substantially reducing crosstalk contributions between each output signal is further configured to solve the set of linear equations for each pixel in the image that produces the output signal by applying a singular value decomposition to a matrix form of the set of linear equations.