US Patent 7830406 LED printer and print control method

An LED printer has a photosensitive drum, a resist roller for feeding a printing medium to the photosensitive drum at a first constant speed, a fixing device for discharging the printing medium from the photosensitive drum at a second constant speed, a separation type LED head arranged zigzag, and a printing control circuit for detecting a position of the printing medium fed by the resist roller or the fixing device and adjusting printing timings of the first portion LED head and the second portion LED head based on the detected position and the LED head interval. The LED printer can normally correct a print length in each of a front end region and a rear end region of a sheet.