| 摘要 |
PURPOSE:To detect exactly a spot position by the dichroic mirrors which are provided to a laser spot projecting optical system as said mirrors reflect or transmit thoroughly laser ray fluxed and are made to function as semi-transparent mirrors for the ray flux of a spot position detecting optical system. CONSTITUTION:The laser spot projecting optical system which condenses the ray flux of a laser light source 1 onto a wafer W via the aperture 4a of a stop member 4 and an objective lens 9 and the spot position detecting optical system which detects the laser spot position via the dichroic mirrors D1, D2 are provided. The mirrors D1, D2 reflect or transmit approximately thoroughly the leaser beam flux and function as the semi-transparent mirrors for the ray flux for spot position detection supplied via a reflecting member 11 from an optical fiber 12. The laser ray flux for processing is thereby efficiently supplied and the optical device for laser beam processing which can detecting exactly the laser spot position is obtd. |
