Patent ID: 7641302

Claim:
An apparatus to compensate for one or more defective nozzles in a printer head having a plurality of nozzles disposed parallel to a direction perpendicular to a paper transfer direction, comprising: a defective nozzle position detection unit to detect a position of a defective nozzle among the nozzles of the printer head; a data storage unit to store data respectively corresponding to the plurality of nozzles indicating whether the nozzles discharge ink; a correlation estimation unit which estimates a correlation between the position of the defective nozzle and data corresponding to the defective nozzle among the stored data at each position to which the printer head moves in a direction perpendicular to the paper transfer direction, and outputs information of a transfer position having the greatest correlation among the estimated correlations; and a print unit to place the printer head at the transfer position having the greatest correlation based on transfer position information provided by the correlation estimation unit and then to perform a print operation.