Abstract: In the initial stage of die-opening operation when an upper core 3 moves upward together with an upper die plate 1, an upper cavity die 2 is biased downwardly by an elastic member 10 so as to press the lower surface of the upper cavity die 2 against the upper surface of a lower cavity die 6 and keep their contact, thereby forcing a molded glass element 4 to remain on a lower core 5 by utilizing the difference in outside diameter between the lower core 5 and the upper core 3. This makes it possible to securely release the molded glass element 4 from the upper core 3 and leave the molded product on the lower core 5 upon die opening, enabling smooth removal and automated transportation of the molded product.

Abstract: In the initial stage of die-opening operation when an upper core 3 moves upward together with an upper die plate 1, an upper cavity die 2 is biased downwardly by an elastic member 10 so as to press the lower surface of the upper cavity die 2 against the upper surface of a lower cavity die 6 and keep their contact, thereby forcing a molded glass element 4 to remain on a lower core 5 by utilizing the difference in outside diameter between the lower core 5 and the upper core 3. This makes it possible to securely release the molded glass element 4 from the upper core 3 and leave the molded product on the lower core 5 upon die opening, enabling smooth removal and automated transportation of the molded product.

Abstract: A metallic material 27 is placed between an upper die 6 and a lower die 13. Inert gas is fed into the processing chamber 17 defined by a transparent quartz tube 16. The dies 6 and 13 are heated together with the metallic material 27 by infrared lamps 20. The dies 6 and 13 are closed to form the material 27.

Abstract: A metallic material 27 is placed between an upper die 6 and a lower die 13. Inert gas is fed into the processing chamber 17 defined by a transparent quartz tube 16. The dies 6 and 13 are heated together with the metallic material 27 by infrared lamps 20. The dies 6 and 13 are closed to form the material 27.

Abstract: A press forming machine for optical devices which manufactures, an optical device from silica glass with a high glass transition point. A transparent quartz tube surrounds an upper die unit, lower die unit, fixed shaft, and moving shaft to form an airtight chamber inside it. Infrared lamps are arranged along the outer surface of the transparent quartz tube, and a reflecting mirror is arranged behind the infrared lamps. A cooling gas jacket is formed to cover the rear surface of the reflecting mirror. The inner-diameter side wall surface of the jacket and the reflecting mirror have many through holes. A cooling gas is sprayed from the interior of the jacket toward the transparent quartz tube through the through holes, thereby cooling the reflecting mirror, quartz bulbs constituting the outer surfaces of the infrared lamps, and the transparent quartz tube.

Abstract: The object of this invention is to provide a press die for press forming of glass, which is capable of preventing the generation of interdiffusion between a matrix material of press die and a releasing film, making it possible to retain the excellent releasability of the releasing film for a long period of time. Matrix body is covered by a diffusion preventive film, which in turn is covered with a releasing film. In this example, the matrix body is constituted by a sintered body of tungsten carbide (WC) containing 3 wt% of titanium carbide and none of metal-based binder, the diffusion preventive film is constituted by a sputtered film of niobium (Nb) 0.05 micrometer in thickness, and the releasing film is constituted by a sputtered film of an alloy consisting of platinum (Pt) and iridium (Ir) 0.3 micrometer in thickness. The diffusion preventive film may be a high-melting point metal such as Ta, Hf, Zr, Re, Ir, Mo, Rh, Ru or Os other than Nb.

Abstract: The object of this invention is to provide a press forming machine for optical devices which manufactures, an optical device from silica glass with a high glass transition point. A transparent quartz tube surrounds an upper die unit, lower die unit, fixed shaft, and moving shaft to form an airtight chamber inside it. Infrared lamps are arranged along the outer surface of the transparent quartz tube, and a reflecting mirror is arranged behind the infrared lamps. A cooling gas jacket is formed to cover the rear surface of the reflecting mirror. The inner-diameter side wall surface of the jacket and the reflecting mirror have many through holes. A cooling gas is sprayed from the interior of the jacket toward the transparent quartz tube through the through holes, thereby cooling the reflecting mirror, quartz bulbs constituting the outer surfaces of the infrared lamps, and the transparent quartz tube.

Abstract: In press molding, a shaft (metal mold 13) is moved by positional or torque control to cause upper and lower molds to reach a set position slightly before a position where the upper and lower molds are set in a final mold closed state. As soon as the upper and lower molds reaches the set position, the control is switched to torque control using a small force which does not deform a glass material to perform feedback control. For this reason, when the cooling process is started, the mobile shaft is moved by the same amount as a contraction amount of the shaft, the actual position of the shaft is moved. However, a tight contact state between the molds and the glass material is kept without changing the thickness of the glass material, and positional control and torque control can be apparently performed at once. Thereafter, when temperature reaches an almost glass transition point, final pressing is performed.

Abstract: A method of manufacturing an optical waveguide comprises a first step of laminating, on one major surface of a first glass material, a second glass material to a desired thickness, the second glass material having optical characteristics different from those of the first glass material, a second step of forming the second glass material to have a desired circuit pattern, and a third step of laminating a third glass material having optical characteristics similar to those of the first glass material on an entire surface of the first glass material on which the circuit pattern is formed by the second glass material. In at least one of the first and third steps, the glass material to be laminated is laminated by coupling.

Abstract: In press molding, a shaft (metal mold 13) is moved by positional or torque control to cause upper and lower molds to reach a set position slightly before a position where the upper and lower molds are set in a final mold closed state. As soon as the upper and lower molds reaches the set position, the control is switched to torque control using a small force which does not deform a glass material to perform feedback control. For this reason, when the cooling process is started, the mobile shaft is moved by the same amount as a contraction amount of the shaft, the actual position of the shaft is moved. However, a tight contact state between the molds and the glass material is kept without changing the thickness of the glass material, and positional control and torque control can be apparently performed at once. Thereafter, when temperature reaches an almost glass transition point, final pressing is performed.