摘要:
An optical pickup apparatus capable of reading information from recording media of different read wavelengths, includes a light-emitter having a first light source for emitting a first laser beam integrated with a second light source for emitting a second laser beam of a different wavelength from that of the first laser beam. The optical pickup apparatus includes a photodetector for receiving a beam reflected by each of the recording media and an optical system having a plurality of optical elements which form an optical path to guide the first and second laser beams to the recording media and which form an optical path for guiding the reflected beam to the photodetector and through which the first and second laser beams pass.
摘要:
An optical pickup apparatus includes a semiconductor laser device having a plurality of light emitting portions for emitting laser beams having different wavelengths on a substrate for emitting a laser beam from one of the plurality of light emitting portions in response to a light emitter selecting instruction in the same emitting direction. The laser beam emitted from the semiconductor laser device is converged by an objective lens and led to a recording surface of an optical disk, and the objective lens is moved to one of a plurality of different positions in a radial direction of the optical disk, corresponding to the selected light emitting portion.
摘要:
An optical pickup apparatus and a laser diode chip which can simplify and miniaturize a construction of the apparatus is provided for using a plurality of laser beams of different wavelengths. The laser diode chip is a chip for the optical pickup apparatus in which a plurality of light emitting portions for emitting the laser beams of the different wavelengths in the same emitting direction are formed on a substrate. Light emitting points of the plurality of light emitting portions are located at positions which are different in the emitting direction.
摘要:
An optical pickup apparatus which supports two wavelengths and is amenable to a reduction in size without employing a combining prism. The optical pickup apparatus employs a semiconductor laser device implemented in the form of a one-chip laser diode having two light sources for emitting a first laser beam and a second laser beam at a wavelength different from that of the first laser beam. A photodetector unit has a first detector section for receiving the first laser beam and a second detector section for receiving the second laser beam, and is set at positions at which the first and second laser beams follow return light paths of different lengths from an optical disc to the first and second detector sections.
摘要:
Laser beams h1, h2 with different wavelengths emitted from semiconductor lasers 2a, 3 are incident to an optical path joint prism 13 and each of optical intensities of the laser beams h1, h2 is detected by a photoelectric conversion element 15 provided in an optical path integrated by the optical path joint prism 13 on which a semi-transmission film HM is provided and APC control of each of light emission intensities of the semiconductor lasers 2a, 3 is performed on a basis of each of detection results. As a result of this, the beam intensity of the laser beam h1 passing through the optical path joint prism 13 to be applied to an information recording medium and the laser beam h2 reflecting the optical path joint prism 13 to be applied to the information recording medium are controlled properly.
摘要:
A reflective mirror 14 is inclined and placed with respect to an objective lens 16 and a photoelectric conversion element 15 for monitor is placed in the back side of the reflective mirror 14. The reflective mirror 14 is formed into a structure in which a semi-transmission film HM having predetermined reflectance and transmittance is formed on one surface of a substrate of a transparent medium. When a laser beam for information record or information reproduction is launched from semiconductor lasers 2a, 3 to the reflective mirror 14, the semi-transmission film HM splits the laser beam into a reflected beam and a transmitted beam and the reflected beam is emitted to the side of the objective lens 16 and the transmitted beam is emitted to the side of the photoelectric conversion element 15. As a result of this, any laser beams for the information record and the information reproduction can be detected by one photoelectric conversion element 15 to perform APC control of the semiconductor lasers 2a, 3 and the intensity of the laser beam for the information record and the information reproduction with respect to an information record medium can be controlled properly.
摘要:
A pipe joint construction for joining two pipes by having a bead formed on the outer side near the end of one of the pipes being joined and a radially expanded portion for embracing therein a sealing member fitted around the base of said bead formed near the end of the other pipe, setting in position a union screw with the inner end surface thereof in engagement with said radially expanded portion and a nut with the inner end surface thereof in engagement with said beads, and screw tightening the union screw and the nut against each other thereby pressing the leading end of said radially expanded portion into contact with said beads, which pipe joint construction has a tapered portion formed along the inner circumferential edge of the leading end of said union screw so that the leading end of said radially expanded portion will be deformed along the outer circumferential surface of said bead.
摘要:
The invention relates to a receiver-drier for use in an air conditioning system. This receiver-drier has (a) a lower portion defining a lower chamber in the receiver-drier; (b) an upper portion defining an upper chamber in the receiver-drier; and (c) a strainer for removing foreign particles from the refrigerant. The lower portion has an inlet for allowing the refrigerant to flow into the lower chamber and an outlet for allowing the refrigerant to flow out of the lower chamber. Each of the inlet and the outlet is formed at a bottom of the lower portion. The upper chamber is on top of the lower chamber and is charged with a desiccant for removing moisture from the refrigerant. The strainer is disposed at a position in a flow of the refrigerant from the inlet to the outlet.
摘要:
A safety device for an engine cooling system having a heater core circuit for circulating the engine cooling water through the heater core of an automotive air conditioning system, and a radiator circuit for circulating the engine cooling water through a radiator. The safety device comprises a safety valve provided in the heater core circuit and capable of discharging the engine cooling water outside the vehicle when the temperature of the engine cooling water exceeds a predetermined temperature and/or when the pressure of the engine cooling water exceeds a predetermined pressure.