Abstract: An optical pickup equipped with a laser light source which emits light beams of at least three wavelengths for recording/reproducing a plurality of information recording media detects light quantities of the light beams of three wavelengths using one light intensity monitor element. More specifically, one light intensity monitor element is arranged between a first laser light source and a second laser light source, light beams of wavelength ?1 and wavelength ?2 emitted from the first laser light source are made to proceed substantially straightforward, the optical path of the light beam of wavelength ?3 emitted from the second laser light source is changed to a diagonal one so as to cause the light beam to be introduced diagonally to the light receiving surface of the one light intensity monitor element.

Abstract: In an information reproducing apparatus in which a liquid crystal lens element is used for the selection and switching of layers, the instability of servo control during the switching of the layers due to the overlapping of signals from two layers is eliminated and the focal point is shifted onto the correct switched layer. During the switching of the liquid crystal lens, a focus bias is added depending on the direction in which the layers are switched so as to stabilize servo control. Alternatively, the objective lens is held during the switching and after the switching of the liquid crystal lens element, the hold state is released in synchronization with the rotation of the disk.

Abstract: The invention provides an optical disc apparatus which restricts an operation sound generated from an objective lens driving portion of an optical pickup and has a reduce sound, in an optical disc apparatus, in particular, an optical disc apparatus installing a microphone for recording an external voice therein. Coils (107, 108), a magnet (109) and opposing surfaces of a yoke (110) are respectively arranged at substantially point symmetrical positions with respect to an optical axis (111) of an objective lens (103) in a state in which no electric current is applied, the yoke (110) and a unit base (117) are connected via a spring member (118), and the unit base (117) is mounted to a casing (120). In this case, the spring member (118) is connected at a position (121) forward apart from the objective lens (103) with respect to the yoke (110), and is formed so as to have at least a deformation freedom in a direction of the optical axis of the objective lens (103).

Abstract: An optical pickup and an optical information recording and reproducing device in which spherical aberration correction control after a disc is loaded can be efficiently made in a short time. Before an information recording medium is loaded into a drive, an optical axis direction position of a concave lens is preset to a state so as to optimize a converging spot on a recording surface of a single-layered medium of as a first recording medium or a predetermined layer (first layer having a substrate thickness of 0.1 mm) of a medium having two or more layers to which the recording/reproduction is executed by a laser light source. After the information recording medium is loaded, if it is determined to be a second (third) recording medium to which the recording/reproduction is executed by a laser light source, setting of the optical axis direction position of the concave lens is changed.

Abstract: The invention provides an optical disc apparatus which restricts an operation sound generated from an objective lens driving portion of an optical pickup and has a reduce sound, in an optical disc apparatus, in particular, an optical disc apparatus installing a microphone for recording an external voice therein. Coils (107, 108), a magnet (109) and opposing surfaces of a yoke (110) are respectively arranged at substantially point symmetrical positions with respect to an optical axis (111) of an objective lens (103) in a state in which no electric current is applied, the yoke (110) and a unit base (117) are connected via a spring member (118), and the unit base (117) is mounted to a casing (120). In this case, the spring member (118) is connected at a position (121) forward apart from the objective lens (103) with respect to the yoke (110), and is formed so as to have at least a deformation freedom in a direction of the optical axis of the objective lens (103).

Abstract: The invention provides an optical disc apparatus which restricts an operation sound generated from an objective lens driving portion of an optical pickup and has a reduce sound, in an optical disc apparatus, in particular, an optical disc apparatus installing a microphone for recording an external voice therein. Coils (107, 108), a magnet (109) and opposing surfaces of a yoke (110) are respectively arranged at substantially point symmetrical positions with respect to an optical axis (111) of an objective lens (103) in a state in which no electric current is applied, the yoke (110) and a unit base (117) are connected via a spring member (118), and the unit base (117) is mounted to a casing (120). In this case, the spring member (118) is connected at a position (121) forward apart from the objective lens (103) with respect to the yoke (110), and is formed so as to have at least a deformation freedom in a direction of the optical axis of the objective lens (103).

Abstract: A vane pump has a casing, a rotor rotatably mounted in the casing, and a plurality of vanes mounted in the rotor and projecting variable amounts from an outer peripheral wall of the rotor. The outer peripheral wall of the rotor and an inner peripheral wall of the casing are shaped cylindrical. The rotor has an axis of rotation offset from the center of the inner peripheral wall of the casing. Stationary cams concentric with the inner wall of the casing act on proximal ends of the vanes, so that distal ends of the vanes revolve in close vicinity of but not in pressure contact with the inner wall of the casing.

Abstract: There is disclosed a hot gas generator comprising a compressor for supplying compressed air to a combustion chamber, a gas turbine driven by hot gas flowing from the combustion chamber and operatively connected to the compressor by means of a common rotary shaft, a blower for starting the compressor, an air pressure sensor for detecting an inlet pressure of air supplied to the compressor, a flame monitoring sensor for confirming ignition, a valve for controlling fuel gas supply to the combustion chamber, and a control mechanism. The control mechanism is operable to open the valve to a certain extent and actuate an ignition device at the same time upon a predetermined time lapse after blower actuation, to stop the ignition device and open the valve at a predetermined speed at the same time in response to an ignition confirmation signal from the flame monitoring sensor, and to stop the blower in response to a signal from the air pressure sensor indicating that the generator is in self-sustaining operation.

Abstract: A compact electronic device having a calendar function wherein initial data for setting a plurality of specified dates and setting data for setting a plurality of specified dates based on the initial data are input by a key input section. Then, dates to be set as specified dates are calculated by a RAM, a control section and an operation circuit according to the input initial and setting data. The calculated dates are stored in a memory so that the plurality of specified dates may be set.