Patent ID: 8520044

Claim:
A light emitting diode (LED) print head arranged to receive a set of raw print data, the print head comprising: a plurality of LED array chips each comprising a plurality of LEDs, wherein each LED of the plurality of LEDs comprises a process direction position; at least one matrix driver circuit arranged to control activation of the plurality of LEDs in response to the set of raw print data; at least one real-time print data compensation circuit comprising: a line compensation register comprising a delay value based on an average process direction position of the associated respective LED array chip; at least two serial-in-parallel-out (SIPO) shift registers; and, at least two logical OR gates, wherein a first logical OR gate of the at least two logical OR gates receives inputs from the line compensation register, a second logical OR gate of the at least two logical OR gates receives inputs from the line compensation register and the first logical OR gate, and wherein one of the at least two SIPO shift registers is serial enabled by the delay value, and the at least two SIPO shift registers are parallel enabled by the delay value or an output from the second logical OR gate, wherein the at least one real-time print data compensation circuit receives the set of raw print data and delays transmitting the set of raw print data to the at least one matrix drive circuit based on a relative relationship between the process direction position of each LED, wherein each of the plurality of LED array chips comprises the average process direction position calculated from an average of each process direction position of the plurality of LEDs which form a respective LED array chip, and the at least one real-time print data compensation circuit delays transmitting the set of raw print data to the at least one matrix drive circuit based on a relative relationship between the average process direction position of each LED array chip.