An optical scanning device can scan two types of record carriers each having a transparent layer with a different thickness, in which a radiation beam scans an information layer of the record carrier through the transparent layer. When scanning a first type of record carrier the best focus of a scanning radiation beam is positioned on the information layer and when scanning a second type of record carrier the paraxial focus of the radiation beam is positioned on the information layer.
申请公布号
EP0763236(A2)
申请公布日期
1997.03.19
申请号
EP19960903166
申请日期
1996.03.08
申请人
KONINKLIJKE PHILIPS ELECTRONICS N.V.;PHILIPS NORDEN AB