Lens actuator, optical pickup device, and optical recording and reproducing apparatus

A lens actuator comprising:

• an objective lens condensing a light beam on an optical storage medium;
• a diffractive element providing compatibility with optical storage media of plural types of standards relative to light sources of plural different wavelengths;
• and
• a lens holder including the objective lens and the diffractive element in an opposing manner, the objective lens being driven together with the lens holder in at least a focusing direction and a tracking direction relative to the optical storage medium, wherein
• the diffractive element is disposed on the lens holder such that a diffracting plane of the diffractive element is tilted relative to an optical axis of the objective lens and a diffraction pattern center of the diffracting plane in the diffractive element facing the objective lens corresponds to the optical axis of the objective lens.

An optical recording and reproducing apparatus optically recording and reproducing information on an optical storage medium, comprising:

• an optical pickup device including:
• a unit obtaining optical information from a light beam reflected from an optical storage medium;
• and
• a lens actuator having:
• an objective lens condensing a light beam on an optical storage medium;
• a diffractive element providing compatibility with optical storage media of plural types of standards relative to light sources of plural different wavelengths;
• and
• a lens holder including the objective lens and the diffractive element in an opposing manner, the objective lens being driven together with the lens holder in at least a focusing direction and a tracking direction relative to the optical storage medium, wherein
• the diffractive element is disposed on the lens holder such that a diffracting plane of the diffractive element is tilted relative to an optical axis of the objective lens and a diffraction pattern center of the diffracting plane in the diffractive element facing the objective lens corresponds to the optical axis of the objective lens.