PURPOSE: To simply detect the misregistration of many pins projecting from a molded body to utilize the detected result for surface mounting to a substrate by providing a light source part for applying light from the transverse direction toward the tip parts of pins of respective rows and a light-receiving part for detecting the maximum bending quantity of the pins of respective rows from the width of light intercepted by the pins of respective rows.

CONSTITUTION: The visual inspection system for a multi-pin tip with many pins 3 erected in the X- and Y-directions on the principal plane of a molded body 2 is equipped with a light source part 12 for applying light from the transverse direction toward the tip parts of pins of respective rows arranged in parallel in the X and Y-directions, and with a light-receiving part 13 for detecting the maximum bending quantity of pins 3 of respective rows from the width (t) of light intercepted by the pins 3 of respective rows. For example, the title device is provided with the light source part 12 for applying a slit-type laser beam and with a light-receiving part 13 equipped with a light-receiving element 14. The laser beam has an effective width D and is applied from the transverse direction toward the tip parts of pins 3 of respective rows arranged in the X- and Y-directions so that the maximum bending quantity of the pins 3 of respective rows is detected from the width (t) of light intercepted by the pins 3 of those rows.