Abstract: Provided is a cleaning device that does not cause degradation of cleaning performance even if there is an obstacle on a surface to be cleaned. A cleaning device includes a housing, blades used for cleaning, a cleaning liquid supply section for supplying cleaning liquid to a surface of a solar cell module, and a wheel for travelling on a solar photovoltaic power generation device. Moreover, the blades are arranged in such a manner that regions which pass through a fixation member are shifted and overlap each other in a front-rear direction with respect to an advancing direction.

Abstract: A cleaning device includes a nozzle that discharges water toward a light-receiving surface, and a blade that wipes away the water on the light-receiving surface. A hole in the nozzle is arranged so as to face the surface to be cleaned or arranged so as to be inclined to a side of the blade with respect to a reference plane.

Abstract: A conventional optical disk apparatus detects the amount of shift of an objective lens with a tracking error signal and an RF signal, and controls, when an optical pickup is moved, the shift amount for performing high-speed seek and high-speed access. The problem here is that this apparatus cannot be applied to an optical disk having an area where no RF signal is recorded, and requires higher costs. In view of this, an optical disk apparatus of the present invention has a shift signal detecting portion that detects a shift signal based on a push-pull signal generated during generation of a tracking error signal based on the reflected light resulting from a beam reflected from an optical disk, and a shift amount control portion that drives, when an optical pickup is moved, an objective lens actuator based on the shift signal detected by the shift signal detecting portion.

Abstract: An optical pickup (20) projects a read beam onto an optical disc (40) as an optical storage medium which is driven to rotate by a spindle motor (30) and receives its reflection. A laser beam from a laser producing element (21) passes through a liquid crystal panel (25) and guided to an objective lens (26). The panel (25) is provided to correct spherical aberration caused by an irregular thickness of a transparent substrate of the optical disc (40). A control circuit (50) changes a spherical aberration correction signal SA to carry out sampling more than once, covering a range of the output of an optical sensor (31) where the output shows large changes. The circuit (50) determines the position of a peak of an approximation curve through calculation and designates that position as the magnitude of correction. Thus, the optical pickup (20) can quickly and accurately detect the magnitude of the correction of the spherical aberration caused by an irregular thickness of the optical disc (40).

Abstract: In an integrated optical unit of the present invention, a photo detector (12) and a holding member (17) that sustains a semiconductor laser (11) are provided on a polarizing beam splitter (14). This makes it possible to reduce a deviation from a designed value due to tolerance, and adjust a relative positional relationship between the semiconductor laser (11) and the photo detector (12). Therefore, returned light from an optical disk (4) is accurately adjusted with respect to a division line of a photo-detecting device (13). As a result, stable servo-control is realized, and an information signal with fine quality is obtained.

Abstract: It is an object of the present invention to realize stable tracking control even in a structure including an objective lens whose center is offset from a central line extending from the central axis of an optical disk in the direction of the axis along which an optical pick-up is moved. An optical pick-up of the present invention includes a second optical system having (i) a light source for emitting a beam, (ii) a second diffraction grating for splitting, into three beams MB, SB1, and SB2, the beam emitted from the light source, (iii) a second objective lens for converging the three beams on an optical disk, and (iv) a photodetector for detecting a push-pull signal from reflected light obtained by reflecting the three beams. The second objective lens is placed in an offset position offset from a central line.

Abstract: In order to (i) reduce astigmatism due to a diffraction grating capable of compensating light intensity distribution of a light beam emitted by a light source and (ii) simplify fabrication processes, an optical pickup device of the present invention includes: a semiconductor laser 1; a collimator lens 4; a diffraction grating 3 capable of changing light intensity distribution of a light beam emitted by the semiconductor laser 1; a polarizing beam splitter 5 for causing a laser beam reflected by an optical disc 8 to be directed in a direction different from a direction of the light beam emitted by the semiconductor laser 1; and a parallel plate 2 for compensating astigmatism due to the diffraction grating 3, the parallel plate 2 being provided between the semiconductor laser 1 and the collimator lens 4 so as to be inclined to an optical axis of the semiconductor laser 1.

Abstract: In an integrated optical unit of the present invention, a photo detector (12) and a holding member (17) that sustains a semiconductor laser (11) are provided on a polarizing beam splitter (14). This makes it possible to reduce a deviation from a designed value due to tolerance, and adjust a relative positional relationship between the semiconductor laser (11) and the photo detector (12). Therefore, returned light from an optical disk (4) is accurately adjusted with respect to a division line of a photo-detecting device (13). As a result, stable servo-control is realized, and an information signal with fine quality is obtained.

Abstract: An object of the invention is to provide a structure for suppressing occurrence of a track offset in a tracking control using DPP method, and simplified apparatus assembly adjustment. When a diffraction grating provided in an optical pick-up apparatus, diffracts light irradiated from a semiconductor laser at least into zero-order diffraction light and ± first-order diffraction light, disposed adjacent to diffraction area alternately in an extension direction of a grating groove, and an effective diameter of light beam with which the diffraction grating is irradiated is D, and a number of divisions into which the effective diameter D is divided is m (m is an integer of 3 or more), a width W1 and a width W2 are formed to meet W1=W2=D/m.

Abstract: In order to realize a more stable recording/reproducing performance by minimizing decrease of light utilization efficiency, an optical integrated unit 1 of the present invention includes: (i) a semiconductor laser 11 for emitting a light beam 20 to an optical disk 4; (ii) a light receiving element 12 for receiving returning light, which is the light beam 20 reflected by the optical disk 4; (iii) a transparent element 15 for diffracting P polarization component light of the light beam 20 in a direction toward the optical disk 4, and for diffracting S polarization component light of the returning light in a direction toward the light receiving element; and (iv) a ¼ wavelength plate 16 that is provided on a portion, through which the returning light enters the transparent element 15, of the transparent element 15, and that converts the returning light into the S polarization component light.

Abstract: A conventional optical disk apparatus detects the amount of shift of an objective lens with a tracking error signal and an RF signal, and controls, when an optical pickup is moved, the shift amount for performing high-speed seek and high-speed access. The problem here is that this apparatus cannot be applied to an optical disk having an area where no RF signal is recorded, and requires higher costs. In view of this, an optical disk apparatus of the present invention has a shift signal detecting portion that detects a shift signal based on a push-pull signal generated during generation of a tracking error signal based on the reflected light resulting from a beam reflected from an optical disk, and a shift amount control portion that drives, when an optical pickup is moved, an objective lens actuator based on the shift signal detected by the shift signal detecting portion.

Abstract: An optical pickup device includes: a separation section for separating a light beam into (i) a first light beam, which includes an optical axis of the light beam, and (ii) a second light beam, which surrounds a curved side of the first light beam; and a second light receiving section for receiving the light beam. The second light receiving section includes (I) main light receiving regions, which are provided with a division line therebetween so as to be adjacent to each other and (II) auxiliary light receiving regions, which receive a portion of the light beam which protrudes from each of the main light receiving regions. Each of the auxiliary light receiving regions is positioned in a direction orthogonal to a drawing direction of the division line so as to be adjacent to the main light receiving region. The auxiliary light receiving region is shorter than the main light receiving region in the drawing direction of the division line.

Abstract: An optical pickup (20) projects a read beam onto an optical disc (40) as an optical storage medium which is driven to rotate by a spindle motor (30) and receives its reflection. A laser beam from a laser producing element (21) passes through a liquid crystal panel (25) and guided to an objective lens (26). The panel (25) is provided to correct spherical aberration caused by an irregular thickness of a transparent substrate of the optical disc (40). A control circuit (50) changes a spherical aberration correction signal SA to carry out sampling more than once, covering a range of the output of an optical sensor (31) where the output shows large changes. The circuit (50) determines the position of a peak of an approximation curve through calculation and designates that position as the magnitude of correction. Thus, the optical pickup (20) can quickly and accurately detect the magnitude of the correction of the spherical aberration caused by an irregular thickness of the optical disc (40).

Abstract: An object of the invention is to provide a structure for suppressing occurrence of a track offset in a tracking control using DPP method, and simplified apparatus assembly adjustment. When a diffraction grating provided in an optical pick-up apparatus, diffracts light irradiated from a semiconductor laser at least into zero-order diffraction light and ± first-order diffraction light, disposed adjacent to diffraction area alternately in an extension direction of a grating groove, and an effective diameter of light beam with which the diffraction grating is irradiated is D, and a number of divisions into which the effective diameter D is divided is m (m is an integer of 3 or more), a width W1 and a width W2 are formed to meet W1=W2=D/m.

Abstract: Beam shaping means may have a shaping ratio set to allow a light beam emitted from a semiconductor laser and having an elliptic intensity distribution to have an ellipticity of no more than two to obtain a spot achieving high light availability and reduced in size. Furthermore, the shaping ratio can be set to no more than 2.5 to allow a polalized-beam splitter (light separation means) and other components to be arranged in a converged flux passing between the semiconductor laser and a collimator lens.