Misregistration correction using non-pinhole camera model and non-linear scan equations

A method of misregistration correction in a line scanning imaging system, comprising:

• providing the line scanning imaging system with a forward array of optical detectors and a trailing array of optical detectors for receiving optical signals from a scene being scanned and converting the optical signals into electrical signals, the forward array of optical detectors receiving the optical signals at a different time than the trailing array of optical detectors receiving the optical signals, the forward array of optical detectors and the trailing array of optical detectors defining a plurality of detector junction overlap regions;
• receiving the electrical signals at a processor;
• processing the received electrical signals with the processor, the processing comprising the steps of:
• generating a model of scan motion over a focal plane of the imaging system, using a coupled system of non-linear scan equations with constant coefficients;
• estimating programmed motion positions across the plurality of detector junction overlap regions via a state transition matrix solution to the non-linear scan equations;
• at each detector junction overlap region, measuring actual motion positions via image correlation of overlapping detectors;
• generating differences between the actual motion positions and the estimated programmed motion positions;
• estimating updates to the constant coefficients based on the generated differences;
• generating corrections from the estimated updates to remove unwanted motion;
• and
• applying the updates to the constant coefficients;
• wherein
• the steps of generating a model of scan motion, estimating programmed motion positions, measuring actual motion positions, generating differences, estimating updates, generating corrections and applying the updates are performed by means of a non-transitory computer-usable medium having computer-readable code that, when executed by the processor, cause the processor to perform the steps.