| 摘要 |
<p>PROBLEM TO BE SOLVED: To accurately and easily detect whether a hole passed through an insulating layer. SOLUTION: At making of a hole 13 through the insulating layer 10 of a printed wiring board 1 for electrical continuity of a conductor 11, formed on the insulating layer 10 with a conductor 12 formed under the layer 10 and exposing the lower conductor 12 in the bottom of the hole 13, a printed wiring board provided with a treated layer 14, which radiates an electromagnetic wave having a different wavelength from that of a laser beam for machining at performing laser beam machining between the lower conductor 12, and the insulating layer 10 is used as the printed wiring board 1, and at the time as performing of the laser beam machining for making the hole 13 through the insulating layer 10, the remaining state of the layer 10 is discriminated by measuring the change of a signal generated from the treated layer 14 of the board 1. Since the reflected light of the laser beam is not utilized, and electromagnetic waves, radiated from the treated layer 14 provided between the conductor 12 and insulating layer 10 when the laser beam machining is performed, are utilized, whether or not the hole 13 passed through the insulating layer 10 can be detected precisely.</p> |
