QUALITY JUDGING METHOD OF LIGHT-EMITTING ELEMENT PART OF SEMICONDUCTOR CHIP FOR LIGHT EMISSION

摘要

PURPOSE: To shorten the time necessary for judgement when quality of each light emitting element part of a semiconductor chip for light emission of an LED array print head is judged. CONSTITUTION: A voltages applied to each light emitting element part 2a is measured while making a constant current flow through each of the light emitting element parts 2a. Whether the area of each of the light emitting element parts 2a of a semiconductor chip 2 for light emission is larger or smaller than reference is judged in order to judge quality, by comparing each of the measured voltage values with a specified reference value.