Patent Number: 6,310,840

Title: Optical scanning device comprising a main lens and an auxiliary lens

Abstract: An optical player includes an optical scanning device. The scanning device includes an optical lens system for focusing a light beam into a scanning spot on a track of an information carrier. The scanning device includes a first actuator for displacing the lens system parallel to an optical axis for focusing the light beam on the information carrier. The lens system includes a main lens or objective lens and an auxiliary or solid immersion lens, providing the lens system with a large numerical aperture, so that the scanning device is suitable for scanning information carriers with a high information density, such as, for example, high density compact discs. The auxiliary lens is secured in a fixed position to a housing of the lens system, while the main lens is suspended in the housing in a direction parallel to the optical axis by an elastically deformable mounting unit. The lens system includes a second actuator for moving the main lens relative to the auxiliary lens in a direction parallel to the optical axis for compensating for spherical aberration in a transparent protection layer of the information carrier. Thus, the necessary power of the first actuator is limited considerably.

Inventors: Baartman; Jan P. (Eindhoven, NL), Aarts; Jan W. (Eindhoven, NL)

Assignee: U.S. Philips Corporation

International Classification: G11B 7/125 (20060101); G11B 7/09 (20060101); G11B 7/135 (20060101); G11B 007/09 ()

Expiration Date: 10/30/2018