OBJECTIVE LENS ACTUATOR, DIFFRACTIVE OPTICAL ELEMENT, AND OPTICAL PICKUP DEVICE

摘要

An objective lens is directly fixed to one surface of a lens holder. Driving coils that generate focusing thrust and tracking thrust are provided in the lens holder, which is elastically supported by supporting springs according to an amount of thrust generated by the driving coils. A compatible diffractive optical element that outputs a laser beam and is compatible with a reflection signal of the laser beam is directly fixed to the lens holder on the rear side of the objective lens. An inertia ballast is provided on the other surface of the lens holder.