Abstract: Disclosed herein is an apparatus for measuring sub-resonance, which is capable of simultaneously measuring the fundamental frequency characteristics and displacements of an optical pickup actuator through the use of a very simple interferometer. The sub-resonance measuring apparatus of the present invention includes a laser light source, a beam splitter, and an optical detection element. The beam splitter splits light emitted from the laser light source into two light beams. The beam splitter has a reference surface that allows a part of a first beam of the two light beams to be reflected inside of the reference surface and allows the remaining part thereof to pass through the reference surface, and a diffused surface that allows a second beam of the two light beams to be dispersed thereon.

Abstract: The present invention relates an absorptive high temperature desorber for mechanically narrowing the width of the combustion area, and an absorption chiller-heater using the absorptive high temperature desorber. The high temperature desorber comprises a plurality of combustion chambers, a group of liquid ducts arranged in the perpendicular direction in the combustion chambers, and the distribution chambers independently supplying a mixing gas to the plurality of combustion chambers. Therefore, the high temperature desorber can form flame independently and variably in the combustion chamber, and has a mechanically small width.

Abstract: An actuator for an optical unit moves an objective lens in a tracking direction and/or in a focusing direction of a storage medium, such as a disk. A lens holder has recesses in two surfaces opposing each other and being parallel to a photo axis of the objective lens. Elastic rods are supported by a fixed support member and couple the lens holder to the support member. A plurality of fixed coils are fixedly wound about the surfaces of the lens holder parallel or substantially parallel to the photo axis of the objective lens, in such a manner that individual axes of the wound coils forms two acute angles with respect to the photo axis of the objective lens. A magnetic field generation member generates a magnetic field influencing a portion of the plurality of the fixed coils spaced from the lens holder by the recesses. The objective lens moves in a direction designated by the current or currents flowing through the plurality of fixed coils.

Abstract: An optical system driving apparatus is capable of vertically and horizontally driving an optical lens, a part of the lens or a complete optical system including the optical lens. The apparatus is miniaturized and lightened in order to have a rapid response characteristic and a wide control limit, by the utilization of a single magnetic circuit forming a ferromagnetic field between two magnets, and an electronic circuit having a plurality of coil elements having a force acting in each direction in a ferromagnetic field. The optical system is placed in the magnetic field between the two magnets and interlinked to the coil elements, thereby occupying minimal space.

Abstract: A compact optical pickup in which the optical elements are mounted on an optic holder driven as a unitary structure. The pickup includes the optic holder having a vertical hole at one end through which a laser beam passes, a horizontal opening which communicates with the vertical hole, an objective lens installed at the top of the vertical hole, a reflection mirror at the juncture of the vertical hole and horizontal opening, and a hybrid optical unit consisting of optical elements positioned at the other end of the optic holder to scan the reflection mirror with the laser beam via the horizontal opening and detect the laser beam reflected from the disk. The pickup further includes a support for suspending the optic holder from a base, simultaneously keeping balance between the objective lens at the one end of the optic holder and the hybrid optical unit at the other, and elastically supporting the optic holder, and a driver for driving the optic holder vertically and horizontally.

Abstract: An objective lens driving apparatus for an optical pick-up, in which an objective lens is loaded on a driving body which is driven in a horizontal and a vertical direction and an objective lens driving portion is supported by four elastic linear members, includes two supports having two penetration holes each through which two pairs of elastic linear members pass, wherein the objective lens driving body is connected to the two pairs of elastic linear members, so as to prevent the driving body from rolling.

Abstract: An objective lens driving apparatus includes a lens holder holding an objective lens, a focusing coil wound around the vertical outer periphery of the lens holder, yoke members each constituted by an inner yoke and an outer yoke, permanent magnets each retained on the outer yoke to oppose the focusing coils, and tracking coil fixed to the focusing coil. Each tracking coil is twice bent at right angles to wrap around the front, rear and one side of the inner yoke. Electromagnetic forces generated from each upper and lower parts of the tracking coil when the lens holder moves in the horizontal direction, and capable of causing the rolling of the lens holder, offset each other, so that the position of the lens holder is controlled without its axis being inclined and the driving range of the lens holder is wide.

Abstract: An optical pickup, installed in an optical or magneto-optical disc driver, for reproducing/recording optical information is disclosed. The optical pickup is of a subminiature united body type and very light weight, high speed seek, and is composed of an optical system including a hologram lens element. The hologram of the lens element is formed of a predetermined pattern which diffracts a spherical wave and focuses reflected light from the disc onto a detector offset from the light source. This optical pickup can reproduce optical information having no interference and detect focus and track errors without an optical element separating the incident light and reflected light by a hologram pattern. Accordingly, a very light, subminiature optical pickup composed of an optical system having one lens element is provided.