| 摘要 |
PURPOSE:To eliminate nonuniformity in the direction of light inputting from a prism to a microscope by a method wherein the prism delivering upward perpendicularly a light reflected from soldered portions through a gap between a package and a substrate is set with the package used as a reference. CONSTITUTION:A holder 15 is so mounted on a circuit board 12 as to hold a package 11 to be checked, and the inside end face 21 of the holder 15 is made to contact with one side face of the package 11. As the result, a reflecting prism 16 is opposed in a prescribed manner to an array of soldered portions 13 to be checked up. When a light is applied from the back of the circuit board 12 so that the soldered portions 13 be irradiated by the light transmitted by the bard, the form of the soldered portions 13 can be observed by a microscope set above a deflecting prism 17, through the intermediary of a reflecting prism 16 and the deflecting prism 17. |
