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US 11,887,624 B2Granted
Detection apparatus, optical drive, and detection method
AssigneeHuawei Technologies Co., Ltd.
InventorsJia Xu, Jun Xu, Peng Lin
Life of this patent
Estimating the term…
Abstract
A detection apparatus determines whether a recording layer of an optical disc is at a focal point of an objective lens. The detection apparatus includes an objective lens, a beam splitter, a reflector, a detector, and a servo controller. The reflector and the detector are disposed opposite to each other on two sides of an optical axis of the objective lens, and a normal line of the reflector is perpendicular to the optical axis. The beam splitter is disposed between the reflector and the detector and is located on the optical axis. The servo controller is connected to the detector.
Claims20
A detection apparatus, comprising:
- an objective lens comprising an optical axis, wherein the optical axis comprises a first side and a second side, wherein the second side is opposite the first side;
- a beam splitter located on the optical axis and configured to:
- receive an incident pulsed laser beam, wherein a propagation direction of the incident pulsed laser beam is parallel to the optical axis;
- split the incident pulsed laser beam into a first beam and a second beam;
- transmit the first beam in a first transmission direction that is perpendicular to the optical axis;
- and
- transmit, to the objective lens, the second beam in a second transmission direction that is parallel to the optical axis;
- a reflector disposed on the first side, wherein a normal line of the reflector is perpendicular to the optical axis, and wherein the reflector is configured to:
- receive the first beam from the beam splitter;
- reflect the first beam to obtain a third beam;
- and
- transmit, to the beam splitter, the third beam;
- an optical disc comprising recording layers and configured to:
- receive, from the objective lens, second beam;
- reflect the second beam to obtain a fourth beam;
- and
- transmit, to the objective lens, the fourth beam;
- a detector disposed on the second side and configured to:
- receive the third beam and the fourth beam from the beam splitter;
- obtain an interference beam from the third beam and the fourth beam;
- determine an interference signal of the interference beam;
- and
- a servo controller coupled to the detector and configured to determine, based on the interference signal, whether one of the recording layers is located at a focal point of the objective lens.
20 more elements
An optical drive, comprising:
- a light source emitter configured to emit an incident pulsed laser beam;
- and
- a detection apparatus comprising:
- an objective lens comprising an optical axis, wherein the optical axis comprises a first side and a second side, wherein the second side is opposite the first side;
- a beam splitter located on the optical axis and configured to:
- receive an incident pulsed laser beam, wherein a propagation direction of the incident pulsed laser beam is parallel to the optical axis;
- split the incident pulsed laser beam into a first beam and a second beam;
- transmit the first beam in a first transmission direction that is perpendicular to the optical axis;
- and
- transmit, to the objective lens, the second beam in a second transmission direction that is parallel to the optical axis;
- a reflector disposed on the first side, wherein a normal line of the reflector is perpendicular to the optical axis, and wherein the reflector is configured to:
- receive the first beam from the beam splitter;
- reflect the first beam to obtain a third beam;
- and
- transmit, to the beam splitter, the third beam;
- an optical disc comprising recording layers and configured to:
- receive, from the objective lens, the second beam;
- reflect the second beam to obtain a fourth beam;
- and
- transmit, to the objective lens, the fourth beam;
- a detector disposed on the second side and configured to:
- receive the third beam and the fourth beam from the beam splitter;
- obtain an interference beam from the third beam and the fourth beam;
- and
- determine an interference signal of the interference beam;
- and
- a servo controller coupled to the detector and configured to determine, based on the interference signal, whether one of the recording layers is located at a focal point of the objective lens.
24 more elements
A method implemented by a detection apparatus, wherein the method comprises:
- receiving, by a beam splitter, an incident pulsed laser beam, wherein a propagation direction of the incident pulsed laser beam is parallel to an optical axis of an objective lens;
- splitting, by the beam splitter, the incident pulsed laser beam into a first beam and a second beam;
- transmitting, by the beam splitter, the first beam in a first transmission direction that is perpendicular to the optical axis;
- transmitting, by the beam splitter to the objective lens, the second beam in a second transmission direction that is parallel to the optical axis;
- receiving, by a reflector, the first beam from the beam splitter;
- reflecting, by the reflector, the first beam to obtain a third beam;
- transmitting, by the reflector to the beam splitter, the third beam;
- receiving, by an optical disc from the objective lens, the second beam;
- reflecting, by the optical disc, the second beam to obtain a fourth beam;
- transmitting, by the optical disc to the objective lens, the fourth beam;
- receiving, by the optical disc, the third beam and the fourth beam from the beam splitter;
- obtaining, by the optical disc, an interference beam from the third beam and the fourth beam;
- determining, by the optical disc, an interference signal of the interference beam;
- and
- determining, by a servo controller and based on the interference signal, whether a recording layer of the optical disc is located at a focal point of the objective lens.
12 more elements
Dependencies are inferred from the claim text.