KIBANJONOHAISENPATAANKENSHUTSUHOHOOYOBISONOSOCHI

摘要

PURPOSE:To make it possible to detect not only a shortcircuit fault low in light reflectivity but also the fault of a wiring pattern of which only the upper part is broken off without falsely reporting the flaw on the wiring pattern as a fault, by using a reflected light detecting system and a fluorescence detecting part in combiniation and utilizing mutual advantages thereof. CONSTITUTION:An infrared reflected ray detector 15' and an infrared ray reflrecting mirror 20 are provided other than a fluorescence detector 19 and light 31 from high brightness light 11 comes to light 32 having a short wavelength easy to generate the fluorescence of the base material of a printed circuit board 1 by a first filter 16 while the light 32 is changed in its direction by a translucent mirror 17 and allowed to irradiate a wiring surface 2. The fluorescence generated from the base material and fluorescence 42 comprising a combination of intensive reflected light having a short wavelength and reflected light due to infrared rays now transmit the translucent mirror 17 and pass a second filter 18 to form light 43, wherein intensive reflected light having a short wavelength is cut while the light 43 is separated into infrared reflected rays 45 and fluorescence 44 by the infrared ray reflecting mirror 20 and a pattern image is obtained by the infrared reflected ray detector 15' and the fluorescence detector 19.