Method and apparatus for excess signal correction in an imager
View Patent ↗A method and apparatus for excess signal compensation in an imaging system is described. In one particular embodiment, the invention provides for non-linear background, offset (due to time dependent dark current) and/or lag (including constant, linear and non-linear terms, due to image persistence) corrections of large area, flat panel imaging sensors.
1. A method, comprising:
estimating an excess signal based on a non-linear decay response model and a frame rate; and
compensating for the excess signal in the image frame of an imaging system;
wherein the frame rate is faster than one tenth of a frame per second, and wherein estimating is performed using a processor.
2. The method of claim , wherein model comprises a non-linear time variant decay response model.
3. The method of claim 1 , wherein the model comprises a representation of a measured signal of the image frame, and, wherein the frame rate comprises a frame rate of a measured signal of an image frame.
4. The method of claim 1 , further comprising selecting the frame rate.
5. The method of claim 1 , wherein estimating and compensating are performed by an imaging system.
6. A method, comprising:
estimating an excess signal based on a non-linear decay response model of a combination of saturated and non-saturated frames of a measured signal of an image frame of an imaging system; and
compensating for the excess signal in the image frame using the estimated excess sign wherein estimating is performed using a processor.
7. The method of claim 6 , wherein model comprises a non-linear time variant decay response model.
8. The method of claim 6 , wherein the model comprises a representation of a measured signal of the image frame.
9. The method of claim 6 , wherein estimating and compensating are performed by an imaging system.
10. A method, comprising:
estimating an excess signal based on a non-linear time variant decay response model of a measured signal of an image frame of an imaging system; and
subtracting the excess signal from the measured signal of the image frame, wherein estimating is performed using a processor.
11. The method of claim 10 , wherein estimating and compensating are performed by an imaging system.
12. A method, comprising:
estimating an excess signal based on a non-linear decay response model of a measured signal of an image frame of an imaging system; and
compensating for the excess signal in the image frame, wherein estimating the excess signal further comprises selecting a first reference image frame and selecting a second reference image frame, and wherein estimating is performed using a processor.
13. The method of claim 12 , wherein estimating further based on a timed difference between two lag frames, without knowing a frame rate of the imaging system.
14. The method of claim 12 , wherein model comprises a non-linear time variant decay response model.
15. The method of claim 12 , wherein the model comprises a representation of a measured signal of the image frame.
16. The method of claim 12 , wherein estimating and compensating are performed by an imaging system.