Samsung Electronics Co., Ltd.

Lg Electronics Inc.

Sung-hyuk Park

Seong-taek Lim

Woong Lin Hwang

Won-ho Kim

Se-Yong Ro

Seong-Taek Lim

Won-Ho Kim

A motor is provided. The motor includes a stator, a rotor rotatably disposed in the stator, and a motor shaft provided in the rotor to rotate integrally with the rotor. The rotor includes at least one permanent magnet fixing core, at least one injection fixing core alternately stacked with the at least one permanent magnet core in a direction of the motor shaft, a plurality of permanent magnets inserted at a predetermined interval in the at least one permanent magnet fixing core and the at least one injection fixing core, and an injection ring formed to cover the at least one permanent magnet fixing core, the at least one injection fixing core, and the plurality of permanent magnets. The at least one permanent magnet fixing core is formed to prevent the permanent magnets from becoming separated from the rotor by a centrifugal force, and the at least one injection fixing core is formed to prevent the injection ring from becoming separated from the rotor by the centrifugal force.

Motor rotor

A memory chip mounted on an optical disk provided with a data recording region, a TOC (Table Of Content) recording region, a clamp region, and a center hole, includes an MID (Memory In Disk) chip on a portion of the optical disk for recording index data, and a plurality of input/output terminals which are in contact with the MID chip. The optical disk enables index data to be quickly and conveniently recorded and searched for in accordance with physical contact between input/output terminals provided in a recording/reading apparatus and the input/output terminals provided in the optical disk.

Optical disk with a memory chip mounted thereon

Growing community of inventors

Seoul, South Korea

Sung-hyuk Park