Abstract: An optical system of an optical pick-up device 1 comprises a half mirror 13 and a prism 14 which serve to guide a first laser beam L1 for a CD and a second laser beam L2 for a DVD to the optical recording medium side and a common light receiving element 19. The half mirror 13 is set to have a ratio of a reflectance to a transmittance of 5:1 in the first laser beam L1 to be a P polarized light and the prism 14 is set to have a ratio of a reflectance to a transmittance of 1:3 in the first laser beam L2 having a P polarization component and an S polarization component mixed. The first laser beam for a CD can be guided to the optical recording medium without a light quantity loss. At the same time, a return light Lr can be sent in a sufficient light quantity back to the light receiving element 19 for servo signal generation. Therefore, it is possible to implement a reliable CD recording operation by using the first laser beam.

Abstract: An optical pick-up device (1) includes a laser diode (2) for recording which acts as a fixation side light source attached to an attachment portion (5) of a device frame (4) and has a great calorific value, and a laser diode (3) for reproduction which acts as an adjustment side light source held in a holder (6) fixed with an adhesive (7) in a clearance (46) provided on a side surface (45) of the device frame. Heat generated from the laser diode (2) for recording is radiated efficiently through the device frame (4), and heat generated from the laser diode (3) is also radiated efficiently through the holder (6) fixed with the adhesive (7) which is partially filled for the device frame (4) with the clearance (46) formed.

Abstract: An optical pickup apparatus has an objective lens, a lens holder that mounts the objective lens, a main frame holding the lens holder, and first and second inclination angle adjusting mechanism for adjusting angles of inclination of the objective lens. A main shaft guide frame is mounted on one side of the main frame. A main shaft mounted on the main shaft guide frame for guiding the objective lens in a radial direction of an optical disc. An auxiliary shaft guide frame is mounted on another side of the main frame. An auxiliary shaft is mounted on the auxiliary shaft guide groove to allow the objective lens to slidably move in parallel with the main shaft. The first inclination angle adjusting mechanism has a first bearing shaft for rotatably supporting the main shaft guide frame about a first axis with respect to the main frame. The main shaft defines a second axis extending generally in parallel with the main shaft and perpendicular to the first axis.

Abstract: An optical pick-up device 1 comprises a laser diode 2 for recording which acts as a fixation side light source attached to an attachment portion 5 of a device frame 4 and has a great calorific value, and a laser diode 3 for reproduction which acts as an adjustment side light source held in a holder 6 fixed with an adhesive 7 in a clearance 46 provided on a side surface 45 of the device frame. Heat generated from the laser diode 2 for recording is radiated efficiently through the device frame 4, and heat generated from the laser diode 3 is also radiated efficiently through the holder 6 fixed with the adhesive 7 which is partially filled for the device frame 4 with the clearance 46 formed.

Abstract: An optical system of an optical pick-up device 1 comprises a half mirror 13 and a prism 14 which serve to guide a first laser beam L1 for a CD and a second laser beam L2 for a DVD to the optical recording medium side and a common light receiving element 19. The half mirror 13 is set to have a ratio of a reflectance to a transmittance of 5:1 in the first laser beam L1 to be a P polarized light and the prism 14 is set to have a ratio of a reflectance to a transmittance of 1:3 in the first laser beam L2 having a P polarization component and an S polarization component mixed. The first laser beam for a CD can be guided to the optical recording medium without a light quantity loss. At the same time, a return light Lr can be sent in a sufficient light quantity back to the light receiving element 19 for servo signal generation. Therefore, it is possible to implement a reliable CD recording operation by using the first laser beam.

Abstract: A method for manufacturing a precursor wire for a CFRM material, which comprised a continuous carbon fiber bundle of carbon filaments as a reinforcement and a metal as a matrix. In a pretreatment process, the fiber bundle with a sizing agent adhered thereto is passed through an inert atmosphere at a temperature in the range of from 350.degree. to 800.degree. C., thereby thermally decomposing the sizing agent, the chemical structure of the sizing agent including ether linkages, and a residue of thermal decomposition containing the ether linkages is left on the surface of each single filament. In a chemical vapor deposition process, a material gas containing a titanium compound and a boron compound and a reducing gas containing zinc are caused to act simultaneously on the fiber bundle at a temperature in the range of from 700.degree. to 800.degree. C.

Abstract: The present invention relates to a high-strength, high-productivity perform wire for a carbon fiber reinforced aluminum composite material, which comprises: a continuous fiber bundle of carbon filaments having a 2/3-width ranging from 25 to 75 cm.sup.-1, as measured on the basis of Raman spectroscopy, the 2/3-width corresponding to 2/3 of the peak level of a Raman band obtained corresponding to a wave number of about 1,585 cm.sup.-1, the peak level attributed to E.sub.2g symmetric vibration of a graphite structure; one or two materials selected from the group consisting of carbon, silicon carbide, titanium, titanium carbide, boron, and titanium boride, the material(s) covering the individual fibers constituting the continuous fiber bundle; and a matrix consisting essentially of aluminum or aluminum alloy each of which contains 0.1% or less of copper and 0.45% or less of silicon, both by weight based on the weight of matrix, and infiltrated into the continuous fiber bundle.