| 摘要 |
<p>A dam bar (5) is cut by detecting the arranging state of leads (3) with a photoelectric detector (41) and deciding the oscillating timing of pulsed laser light (13A) by processing the detecting signal of the detector (41), and then, relatively moving the axis (13C) of the laser light (13A) at a speed (V0) by means of a machining table (21) while the laser light (13A) is oscillated. At the time of cutting the dam bar (5), the spot (13B) of the laser light (13A) is formed across the width (W1) of the bar (5) by making the length of the spot (13B) two times or more longer than the width (W1) of the dam bar (5) by means of a beam length converter (11a) and width of the spot (13B) 1/2 or more wider than and 4/5 or more narrower than the length of the dam bar (5) by means of a beam width converter (11b), and then, making the length direction of the spot (13B) nearly coincident with that of the leads (3) by appropriately operating a beam rotating device (11c). Thus the cutting accuracy and cut shape of the dam bar (5) are improved.</p> |
