Abstract: The disk-chucking device includes a chuck base having a plurality of arranging parts recessed along an outer periphery of the chuck base and formed at the center of the chuck base with a central boss connected to the motor, a plurality of chuck pins respectively assembled to the arranging parts, a plurality of spring members elastically supporting a rear end of the chuck pins forwardly such that a leading end of the chuck pins can be exposed to an outer surface of the chuck base, and a rigid frame contacting the spring members and formed with a central hole such that the central hole has an inner diameter larger than an outer diameter of the central boss, thereby providing a degree of freedom, which allows the rigid frame to be moved in a horizontal direction within an allowable range.

Abstract: The present invention relates, in general, to a light modulator having a variable blaze diffraction grating and, more particularly, to a light modulator having a variable blaze diffraction grating, in which a diffraction member rotates due to piezoelectric force so as to incline a reflective surface.

Abstract: A vibration speaker is configured to selectively supply an input current in accordance with the frequency of the input current in response to an incoming call, thereby allowing the incoming call to be recognized by sound or vibrations using a single element. The vibration speaker includes a hollow housing with open ends with a vibrating plate attached at one end a shield plate at the other end. A yoke is fixedly mounted to an inner peripheral surface of the housing by plate springs, and a vertically polarized magnet is mounted on the yoke. A voice coil having an upper end fixed to the vibrating plate has a lower end arranged adjacent to the magnet, and a vibration coil is mounted on the shield plate so as to face the magnet. Damping means at the inner peripheral surface of the housing provide damping to the plate springs, thereby reducing the amplitude of vibrations.

Abstract: Disclosed is a vibration speaker configured to selectively supply an input current in accordance with the frequency of the input current in response to an incoming call, thereby allowing the incoming call to be recognized by sound or vibrations using a single element.