LED PRINTER

摘要

PURPOSE:To determine a time for replacing an LED head by a method wherein the breakage of each light emitting element is detected by a detection means, a number of breakage is counted by a counting means, and the number of breakage is indicated on a display means. CONSTITUTION:A printer body control part 41 issues a start signal to an LED breakage detection circuit 35 prior to printing. The LED breakage detection circuit 35 breaks a relay 33 for detecting an LED chip current, thereafter outputting an LED breakage detecting strobe signal, a shift clock, and a light emitting signal to an LED head 3 through OR gates 39, 38, 37, 36. A resistance 32 is connected to light emitting elements in series. Whether an electric current is normally passed through the light emitting elements can be determined based upon the judgement of a comparator 34 whether the resistance ends voltage of the resistance 32 is normal. On the other hand, the LED breakage detection circuit 35 provided with another counter 35b for counting at the detection of a breakage counts the number of broken light emitting elements.