| 摘要 |
PURPOSE:To inspect a board even when mounted parts are at a blind spot of a reflecting light in an apparatus which inspects a surface shape of the board by scanning the mounted printed board with fine beams and receiving the reflecting light, of fine beams by a photoelectric converting element. CONSTITUTION:Fine beams from a light source 1 are deflected by a polygon mirror 3 to scan over a substrate 7. A reflecting light from an irradiated position is received by four photoelectric converting elements 12, 13, 14, 15. Although one of the photoelectric converting elements enters a blind spot in the vicinity of a mounted part, it is distinguished from a difference of luminance, namely, a difference of the detecting amount of light, thereby to inspect the substrate. |
