Abstract: An optical pickup device is provided which includes a double-wavelength objective lens (34) that collects a light beam selectively emitted from a light-emitting/-detecting element (31) that selectively emits a plurality of light beams different in wavelength from each other, and also return light from an optical disk (2), a first diffraction grating (45) that splits the light beam emitted from a light-emitting/-detecting element (31) into three beams including a zero-order light beam and positive and negative first-order light beams, a second diffraction grating (46) that diffracts the return light for traveling along a light path separate from that of the outgoing light, and a third diffraction grating (47) that corrects a light-path deviation by diffracting the positive first-order light beam diffracted by the second diffraction grating (46).

Abstract: This invention is an optical pickup device having a composite optical element (32) which has a first diffraction grating (45) for splitting a light beam emitted from a light source (31) into zeroth-order light, plus-first-order light and minus-first-order light, a second diffraction grating (46) for diffracting the optical path of a return light beam from an optical disc (2), and a split prism (47) arranged at a position where the minus-first-order light diffracted by the second diffraction grating (46) is incident and adapted for splitting the minus-first-order light into a plurality of light beams. It also has a light receiving unit (35) for acquiring a focusing error signal FE by receiving each return light beam split by the split prism (47) and for acquiring a tracking error signal by receiving return light beams from the optical disc (2) of the plus-first-order light and the minus-first-order light split by the first diffraction grating (45).

Abstract: A channel capacity is increased by using MIMO (multiple input multiple output) radio relaying system. A transmission is made from a transmitter 10 using a first antenna 111 and a second antenna 112 having polarization characteristics which are orthogonalized to each other. A reception is made in a repeater 201 using reception antennas 211 and 212 each having the same polarization characteristic as the first and the second antenna 111 and 112, respectively. Each signal received by the first and the second reception antenna 211 and 212, respectively, is passed through loop interference suppressors 271 and 272, respectively, and through amplifiers 241 and 242, respectively, to be transmitted from the first and the second transmission antenna 211 and 212 having the same polarization characteristics as the second and the first antenna 112 and 111, respectively.

Abstract: An optical pickup device is provided which includes a first diffraction grating (45) that splits a light beam emitted from a light-emitting/-detecting element (31) into a zero-order light beam and positive and negative first-order light beams, a second diffraction grating (46) that diffracts return light from an optical disk (2) for traveling along a light path separate from that of the outgoing light, and a third diffraction grating (47) that corrects the deviation of the light path by diffracting the positive first-order light beam diffracted by the second diffraction grating (46). The light-emitting/-detecting element (31) provides a focusing error signal FE by detecting the negative first-order light beam, and a tracking error signal by detecting return portions of the positive and negative first-order light beams from the first diffraction grating (45).

Abstract: This invention relates to an objective lens driving device which moves an objective lens; an optical pickup device, comprising this objective lens driving device, which condenses a light beam onto the information recording surface of an optical disc; and an optical information recording and/or reproduction device, comprising this optical pickup device, which drives in rotation an optical disc and moves the optical pickup device to record and/or reproduce information signals onto or from the information recording surface. Two printed coil boards, with a first printed coil with a first shape formed on at least one face and a second printed coil with a second shape formed on the other face, are provided in parallel in an objective lens driving device of this invention, and a moveable portion on which an objective lens is provided is connected with the two printed coil boards; also, a magnet is positioned between the two printed coil boards provided in parallel.

Abstract: An optical pickup apparatus includes a movable unit with an objective lens, a focus servo coil for moving the objective lens in the optical-axis direction, and tracking servo coils for moving the objective lens in the horizontal directions. Furthermore, a liquid crystal element is disposed for correcting the refractive index. Power feeding to the liquid crystal element and support for the movable unit are provided simultaneously by springs. Two sheets each having four springs extending across an opening on the sheet are disposed parallel to each other at a predetermined distance. On these sheets, a fixed unit and a movable unit are formed by insert-molding. Then, an objective lens, a focus servo coil, tracking servo coils, and a liquid crystal element are mounted on the movable unit.

Abstract: An optical pickup device and an optical information recording and/or reproducing apparatus which make it possible to stably secure electrical wires at predetermined locations in a slide base when forming the slide base by covering a surface of a circuit core, which functions as an electrical wiring, with an external base portion, with a portion of the circuit core being exposed. The slide base includes a circuit core and an external base portion. The circuit core is an electrical conductor forming an electrical circuit for supplying electricity to a bi-axial actuator. The external base portion is an insulating member for covering a surface of the circuit core with a portion of the circuit core being exposed. An external frame is continuously formed with the outer side of the circuit core and is cut off from the circuit core after covering the circuit core with the external base portion by injection molding.

Abstract: This invention relates to an objective lens driving device which moves an objective lens; an optical pickup device, comprising this objective lens driving device, which condenses a light beam onto the information recording surface of an optical disc; and an optical information recording and/or reproduction device, comprising this optical pickup device, which drives in rotation an optical disc and moves the optical pickup device to record and/or reproduce information signals onto or from the information recording surface. Two printed coil boards, with a first printed coil with a first shape formed on at least one face and a second printed coil with a second shape formed on the other face, are provided in parallel in an objective lens driving device of this invention, and a moveable portion on which an objective lens is provided is connected with the two printed coil boards; also, a magnet is positioned between the two printed coil boards provided in parallel.

Abstract: This invention is an optical pickup device having a composite optical element (32) which has a first diffraction grating (45) for splitting a light beam emitted from a light source (31) into zeroth-order light, plus-first-order light and minus-first-order light, a second diffraction grating (46) for diffracting the optical path of a return light beam from an optical disc (2), and a split prism (47) arranged at a position where the minus-first-order light diffracted by the second diffraction grating (46) is incident and adapted for splitting the minus-first-order light into a plurality of light beams. It also has a light receiving unit (35) for acquiring a focusing error signal FE by receiving each return light beam split by the split prism (47) and for acquiring a tracking error signal by receiving return light beams from the optical disc (2) of the plus-first-order light and the minus-first-order light split by the first diffraction grating (45).

Abstract: The present invention has for its object to provide a compact and simplified optical pickup device which secures sufficient quantity of converged light required for recording and reproducing onto/from respective optical disks, can obtain required imaging magnification of respective optical systems, and does not generate performance degradation at lens shift, when recording or reproduction is performed onto/from optical disks with different base material thickness by plural optical systems of a single optical pickup device.

Abstract: A method of reproducing a mirage-like phenomenon which comprises forming a structure comprising at least two see-through phases wherein the density of a lower phase in contact with an upper phase is larger than that of the upper phase, the density ratio (A) therebetween is 1<A<50 and the interface between the lower phase and the upper phase has an even or curved surface.