| 摘要 |
PURPOSE:To provide a simplified method for visually inspecting a light emitting element with improved detection efficiency. CONSTITUTION:A light receiving part 2 obtains the image of a subject 6 to be inspected, an operating part 3 calculates the differential coefficients of brightness between the obtained image and the adjacent pixels, and at the same time, a differential coefficient judgement value is calculated based on the formula previously set and stored in a storing part 4, according to the brightness at the center of the subject 6. The differential coefficients are compared with the differential coefficient judgement value by the operating part 3, and a judging part 5 judges whether the appearance is acceptable or not, based on the result of comparison. Thus, efficient inspection is performed according to the condition of the brightness diviation, so as to suppress foreign materials and scratch defects on the light emitting surface of the subject 6 to be in the prescribed range. |
