Optical pickup device and optical disk apparatus

An optical pickup device comprising:

• a laser source which emits a laser beam having a predetermined wavelength;
• first and second objective lenses which cause the laser beam to converge onto a recording medium;
• a polarization beam splitter which is disposed between the laser source and the first and second objective lenses;
• a first optical system which guides the laser beam transmitted through the polarization beam splitter to the first objective lens;
• a second optical system which guides the laser beam reflected by the polarization beam splitter to the second objective lens;
• first and second optical elements which are respectively disposed in the first and second optical systems such that optical axes of the first and second optical elements become in parallel with each other, the first and second optical elements being moved in optical axis directions of the laser beams to adjust optical characteristics of the laser beams respectively;
• an actuator which drives a holder integrally holding the first and second optical elements in the optical axis directions of the first and second optical elements;
• and
• a wave plate which is disposed in an optical path between the laser source and the polarization beam splitter, the wave plate being inserted in and retracted from the optical path to change the polarization direction of the laser beam incident to the polarization beam splitter,
• wherein the first and second optical elements are moved in a direction in which the wave plate is inserted and retracted during the optical characteristic adjustment,
• the wave plate is disposed in a support portion integral with the holder holding the first and second optical elements,
• the actuator moves the holder in both a first stroke for the optical characteristic adjustment with the first optical element and a second stroke exceeding the first stroke,
• the holder is moved between the first stroke and the second stroke to insert and retract the wave plate in and from the optical path,
• the polarization direction of the laser beam incident to the polarization beam splitter is adjusted such that the laser beam is guided to the first optical system, when the holder is located in the first stroke, and
• the polarization direction of the laser beam incident to the polarization beam splitter is adjusted such that the laser beam is guided to the second optical system, when the holder is located in the second stroke.

An optical disk apparatus comprising:

• an optical pickup device;
• and
• a servo circuit which controls the optical pickup device,
• wherein the optical pickup device including:
• a laser source which emits a laser beam having a predetermined wavelength;
• first and second objective lenses which cause the laser beam to converge onto a recording medium;
• a polarization beam splitter which is disposed between the laser source and the first and second objective lenses;
• a first optical system which guides the laser beam transmitted through the polarization beam splitter to the first objective lens;
• a second optical system which guides the laser beam reflected by the polarization beam splitter to the second objective lens;
• an optical element which is disposed in one of the first and second optical systems, the optical element being moved in an optical axis direction of the laser beams to adjust an optical characteristic of the laser beam;
• an actuator which drives the optical element;
• and
• a wave plate which is disposed in an optical path between the laser source and the polarization beam splitter, the wave plate being inserted in and retracted from the optical path to change the polarization direction of the laser beam incident to the polarization beam splitter,
• wherein the optical element is moved in a direction in which the wave plate is inserted and retracted during the optical characteristic adjustment,
• the wave plate is disposed in a support portion integral with the holder holding the optical element,
• the actuator moves the holder in both a stroke for the optical characteristic adjustment and an additional stroke exceeding the stroke for the optical characteristic adjustment,
• the holder is moved between the stroke for the optical characteristic adjustment and the additional stroke to insert and retract the wave plate in and from the optical path,
• the polarization direction of the laser beam incident to the polarization beam splitter is adjusted such that the laser beam is guided to the optical system not having the optical element in the first and second optical systems, when the holder is located in the additional stroke, and
• the polarization direction of the laser beam incident to the polarization beam splitter is adjusted such that the laser beam is guided to the optical system having the optical element in the first and second optical systems, when the holder is located in the stroke for the optical characteristic adjustment, and
• wherein the servo circuit controls the actuator to adjust the optical characteristic of the laser beam, and the servo circuit controls whether the laser beam is guided to the first or second optical system.