Single-scan time delay and integration color imaging system

Abstract

An electronic imaging system develops red, green and blue images of a document in a single pass of the document through the system. The system includes an image sensor which has three time delay and integration (TDI) sensor arrays. Each sensor array is configured to have two optically masked rows of charge coupled devices (CCD's) for every row of CCD's that is used for imaging. The sensor arrays are arranged so that the first row of imaging CCD's on any two successive arrays are separated by a distance of an integer, K, times three times the height of a picture element (pel) of the image of the document that is projected onto the image sensor, plus or minus one pel height. The spectral component of the image of the document that is projected onto the image sensor is changed in sequence from red, to green, to blue. As the spectral component projected onto the image sensor is changed, the image of the document is scanned down the image sensor by a distance of one pel height. By this scheme, each line of pels in the document is imaged in each of the sensor arrays in a respectively different spectral component. A document may be imaged in all three colors in a single pass through the system without having dedicated filters for each of the separate sensor arrays.