Samsung Electronics Co., Ltd.

Samsung Electro-Mechanics Co., Ltd.

Hag-hyeon Jang

Jang-hoon Yoo

Soo-han Park

Ho-Sik You

Bong-gi Kim

Yong-han Yoon

Soo-Jin Jung

An optical pickup device according to an embodiment of the present invention comprises a light source for projecting a beam of light to record and reproduce information with respect to an optical recording medium. A collimating lens is disposed on a path of the light to converge and convert the light into a parallel beam. An object lens condenses the parallel beam from the collimating lens and projects the parallel beam onto the optical recording medium. An optical element is disposed between the collimating lens and the object lens. A first actuator moves the collimating lens along the optical axis to thereby control a distance between the collimating lens and the optical element. A first controller drives the first actuator to find a position for the collimating lens, for reducing aberration generated in the light being projected to the optical recording medium. Accordingly, the aberration can be effectively prevented, thereby improving recording and reproducing performance of the optical pickup device.

Optical pick-up device

An optical pickup which is compatible with different types of media is disclosed. A plurality of light sources emit light with different wavelengths. Light path changers change the path of light emitted by the plurality of light sources so that the light is incident upon an objective lens. The objective lens focuses the incident light onto a recording medium. A collimating lens is disposed in front of the objective lens to collimate the incident lights. The collimating lens is movable to correct a spherical aberration. A diffractive optical element is disposed in a path of a light with a short wavelength and has a diffractive surface to correct a chromatic aberration.

Optical pickup which is compatible with multiple types of media

An optical pickup apparatus includes a first objective lens having a low numerical aperture (NA) suitable for a low density recording medium, a second objective lens having a high NA suitable for a high density recording medium, a first light source that emits short wavelength light which is focused onto an optical recording medium by the first and second objective lenses, a first photodetector that receives a returning reflected light from the optical recording medium, and a first optical path converter for selectively guiding part of the light emitted from the first light source towards the first or the second objective lens, and guiding the reflected light towards the first photodetector.

Optical pickup apparatus which is compatible with multiple types of media

An optical pickup is provided which includes a light source and an objective lens for converging incident light from the light source onto a recording medium. The objective lens is arranged to be movable in radial and vertical directions of the recording medium. A holographic optical element (HOE) for changing a traveling path of the incident light is positioned along an optical path between the light source and the recording medium, and has first and second diffraction plates which are divided along a first boundary line and have different diffraction patterns. A photodetector has first and second divided plates which are divided along a second boundary line which is perpendicular to the radial and vertical directions of the recording medium. The first and second divided plates receive light passed through the first and second diffraction plates after being reflected from the recording medium. The first boundary line of the HOE is arranged at a predetermined angle with respect to the radial direction of the recording medium, such that the amount of light received by the first and second divided plates is equal to each other when the center of the objective lens is properly located on the optical path, and amount of light received by the first and second divided plates is different from each other when the center of the objective lens is deviated from the optical path.

Growing community of inventors

Seongnam-si, South Korea

Hag-hyeon Jang