| 摘要 |
<p>A device for treating a substrate with laser radiation is described. The device has a rotating polygon mirror with N reflecting surfaces which are used to direct a laser beam via a system of converting focusing lenses, whereby the focal planes of the lenses are located on a surface of the substrate. Active reflecting surfaces direct the laser beam onto the converging lens system, and subsequently on the substrate, while inactive reflecting surfaces have a different inclination to the active reflecting surfaces in relation to the converging lens system. The laser beam from the surfaces is directed onto an absorber. The large number of inactive reflecting surface helps to reduce serial hole density. When the laser is switched on and off while the inactive reflecting surfaces are being scanned, further reduction of serial hole density can be achieved.</p> |
