Sharp Kabushiki Kaisha Corporation

Seiichi Nagatome

Toshiyuki Tanaka

Tomoyuki Miyake

Toshio Tahira

Akihiro Suzuki

Hideaki Fujita

Tohru Okuda

Shigeaki Kakiwaki

Kazuhiko Ueda

Kazushi Fujioka

Hiroki Okuno

A particle detection device detects a biological particle. The particle detection device includes a collection unit that collects a particle to a collection substrate, a fluorescence detection unit that emits excitation light toward the particle collected on the collection substrate and receives fluorescence emitted from the particle, and a cleaning unit that removes the particle from the collection substrate at a refreshing position separated from a collection/heating position and a detection position. At the collection/heating position, the particle is collected onto the collection substrate by the collection unit. At the detection position, fluorescence is received by the fluorescence detection unit. With such a structure, the particle detection device in which the particle is highly accurately detected is provided.

Particle detection device

In an objective lens actuator, when an action force generation force including a focus coil and a magnetic circuit generates an action force for displacing an objective lens holder in a focus direction of an optical disk, a leaf spring supports the magnetic circuit with respect to an actuator base, in such a manner that the magnetic circuit can be rotated about an arbitrary point in the leaf spring, by a reaction force of the action force. At the same time, the equation a&equals;I/Mh is satisfied, where M is a mass of the magnetic circuit, I is a moment of inertia of the magnetic circuit about a center of gravity, a is a distance between the center of gravity of the magnetic circuit and a line of action in a direction of the action force, and h is a distance between a center of rotation in the leaf spring and the center of gravity of the magnetic circuit. As a result, even if the reaction force of the action force acting on the objective lens holder is generated, stable focus servo can be performed, and the actuator can be downsized with a simple structure.

Objective lens actuator

The magnetic head of the present invention includes a magnetic body in the form of a flat plate, and a magnetic pole in the form of a pillar for applying a magnetic field to a recording medium, which is provided to rise on a portion of the magnetic body which is offset in one direction from a center of the magnetic body, and is provided with a coil around its outer periphery. Thus, the magnetic head has a core of a raised shape which is composed of the pillar-shaped magnetic pole being attached to the magnetic body in the form of a flat plate, making it possible to provide a heat capacity and a heat radiation area required for the core and the magnetic body, respectively, thus adapting to high frequencies. Further, because the magnetic pole is provided on a position which is offset in one direction from the center of the magnetic body, there will be no interference between the magnetic head and the cartridge or mechanical components even when the size of the core is increased due to the core of the raised shape. As a result, less restriction is imposed on a moving range of the magnetic head, thus using the entire recording area of the recording medium.

Magnetic head and magnetic head assembly using the same

A magneto-optical recording and reproduction device includes an optical pickup for irradiating a magneto-optical disk with a laser beam for performing at least one of information recording to a magneto-optical disk, information reproduction from the magneto-optical disk, and information erasure from the magneto-optical disk; a magnetic head for providing a magnetic field to a position of the magneto-optical disk irradiated with the laser beam for performing at least one of the information recording and the information erasure, the magnetic head being located opposite to the optical pickup with respect to the magneto-optical disk where the magneto-optical disk is mounted on the magneto-optical recording and reproduction device; a housing for accommodating the optical pickup; a guide shaft for moving the housing; a suspension for supporting the magnetic head; and an arm for connecting the suspension and the housing. The guide shaft is on a straight line extending in a direction perpendicular to a plane of the magneto-optical disk from the center of gravity of a combination of at least the arm, the magnetic head and the suspension, so as to suppress a vibration of the arm, with the guide shaft being a fulcrum of the vibration.

Magneto-optical recording and reproduction apparatus exhibiting suppressed vibration

A magnetic head of the present invention is to switch a direction of magnetic fields applied to a heated portion in a recording region in accordance with recording information. The magnetic head is composed of a single magnetic pole in a pillar shape and a coil. The magnetic pole is provided on a magnetic base, with one end surface of the magnetic pole brought into contact with the magnetic base. The coil, wound around the magnetic pole, is provided for generating the foregoing magnetic fields. The foregoing arrangement enables suppression of heat generation at the magnetic head, thereby allowing the recording frequency to be set higher, as well as improving the recording rate.

Magnetic head

An image forming apparatus including a rotatably driven transfer drum is provided. The transfer drum includes a main body and a dynamic vibration reducer. The dynamic vibration reducer includes an inertia pipe having an inertial moment, and at least one element connecting the inertia pipe to the interior of the main body so as to provide a spring-like property and a damping property therebetween. The apparatus dynamically reduces vibrations in a predetermined frequency band, such as that of the natural frequency of a specific gear, or the natural frequencies of an entire drive mechanism. In particular, the apparatus reduces vibratory peaks generated during the operation of the image forming apparatus.

Image forming apparatus with dynamic vibration reduction

A multi-beam optical head includes a plurality of light sources for emitting a plurality of light beams. An optical system for irradiating the light beams onto the recording surface of a recording medium is included and receives the light beams reflected from the recording medium. The optical system includes a reflecting mirror for directing the light beams emitted from the light sources toward the recording medium; a photodetector for detecting the light beams received by the optical system and for generating electric signals based on the detected light beams; and rotational controller for controlling the reflecting mirror to rotate around an axis which is perpendicular to the recording surface by an amount determined based on the electric signals. The reflecting mirror positions the light beams on tracks on the recording surface of the recording medium. The tracks are tracks on which information is recorded from which the information is reproduced.

Growing community of inventors

Tenri, Japan

Seiichi Nagatome