A combined raster input and output scanner employing spaced document reading and copy printing arrays at a common read/write station. The document to be read and the copy to be printed are disposed in back to back relation and fed simultaneously to the read/write station between the document reading and copy printing arrays. The image reading array is a monolithic full line chip having dual staggered rows of image sensors with individual lenslets for focusing each sensor onto a scan line at the read/write station. To reduce cost, a minimum number of image sensors with relatively wide spacing therebetween is used. To offset loss of resolution, the reading array is movable between a first reading position where one-half of the document line is scanned and a second reading position where the remainder of the line is scanned. The copy printing array comprises a full line of ink jet nozzles, the number and disposition of the ink jet nozzles corresponding to the image sensors, the copy printing array being similarly movable between first and second copy printing positions concurrently with the reading array to thereby print the line in similar half-line increments.