Abstract: A coating method for coating a crucible and a quartz crucible for growing a silicon crystal are provided. In the coating method, a bubble-free quartz layer which is 80 ?m to 4 mm thick is formed on an inner surface of a crucible for growing a silicon crystal, and the surface of the bubble-free quartz layer is covered with alkaline earth hydroxide, following which heating is performed to a temperature at which the surface becomes devitrified. The surface may be covered by immersing the inner surface in a solution of the alkaline earth hydroxide. The heating may be performed before the crucible for growing silicon crystal is filled with a solid raw material to be melted.

Abstract: An Eu-doped SrI2 single crystal having a fluorescence spectrum in which the intensity ratio of defect-related luminescence at around 550 nm to Eu-derived luminescence at around 430 nm is 1% or less, the fluorescence spectrum being measured at room temperature using ultraviolet light having a wavelength of 193 nm as excitation light, and a radiation detector that includes a scintillator that includes the Eu-doped SrI2 single crystal.

Abstract: A coating method for coating a crucible and a quartz crucible for growing a silicon crystal are provided. In the coating method, a bubble-free quartz layer which is 80 ?m to 4 mm thick is formed on an inner surface of a crucible for growing a silicon crystal, and the surface of the bubble-free quartz layer is covered with alkaline earth hydroxide, following which heating is performed to a temperature at which the surface becomes devitrified. The surface may be covered by immersing the inner surface in a solution of the alkaline earth hydroxide. The heating may be performed before the crucible for growing silicon crystal is filled with a solid raw material to be melted.

Abstract: The apparatus is provided with a vessel 1 for accommodating a melt 3 of material sought to be crystallized, and heaters 2 disposed symmetrically on both sides of the vessel. The vessel 1 has an interior space whose front cross section is symmetrical in shape along a vertical center line. The heaters 2 heat the vessel to create a temperature distribution in the melt in which the upper part of the vessel 1 is at a higher temperature, and the lower part thereof is at a lower temperature. The temperature distribution causes symmetrical convection flows of the melt in such a manner that two flows each move up along the side walls of the interior space of the vessel 1 and meet with each other at the top of the interior space where the vertical center line runs, and move together down along the vertical center line toward the bottom of the interior space. A single crystal is formed as the temperature at the lower end of the vessel 1 is gradually lowered below the melting point of the material.

Abstract: A fluoride-based fluorescent material designated by a composition formula of MFn:R, wherein M is at least one element selected from the group consisting of rare earth elements, Al and Bi, alkaline earth metals, and alkaline metals, and R is a rare-earth-based activator including at least either Tb or Tb and Ce and n=1, 2 or 3. The fluoride-based fluorescent materials efficiently emit white-light of a luminescent peak at 543 nm.

Abstract: A thermoelectric chip unit (1) comprises equal numbers of n-type thermoelectric semiconductor elements (30n) and p-type thermoelectric semiconductor elements (30p) that are held embedded within a single chip substrate (2). It is therefore difficult for the crystals of the thermoelectric semiconductor elements (30) to split at the cleavage surfaces thereof. The thermoelectric chip unit (1) can be made to be flexible by forming the chip substrate (2) of a flexible insulator such as plastic or rubber. A thermoelectric unit (4) comprises this thermoelectric chip unit (1) to which are attached electrodes (5). The thermoelectric unit (4) can be made to be flexible by forming the electrodes (5) of flexible members such as thin copper plates. A thermoelectric module (6) comprises the thermoelectric unit (4) to which is attached a flexible sheet or cover (8). This thermoelectric module (6) can be used as a cooling device for a computer's CPU or a semiconductor laser, or in an insulated refrigerator.

Abstract: A thermoelectric component is provided. The component comprises a partition plate with electrical insulation, P-type and n-type thermoelectrical semiconductor elements that are equal in number and retained with juts in the partition plate, flat metallic electrodes connected to the cold junction of the p-type and n-type thermoelectric semiconductor elements, and T-shaped metallic electrodes connected to the hot junction of the p-type and n-type thermoelectric semiconductor elements.

Abstract: A shaper (2) is arranged within a shaping vessel (1). A raw material for a crystal is inserted into the shaping vessel (1) and a crystal melt (5) is formed by setting it in a predetermined atmosphere and heating it. A mechanical force F1 is applied to the crystal melt (5), which is present on the upper surface of the shaper (2), by a pressuring member (4) from above. The crystal melt (5) has nowhere to escape but a gap (3) formed by the shaper(2), so it is injected into that gap (3) as shown by the arrow. This method of fabricating a shaped crystal is suitable for fabricating a monocrystal or multicrystal semiconductor from a material such as silicon, germanium, or bismuth telluride.

Abstract: An infrared optical fiber comprises a core preponderantly made of a halogenide and a trace quantity of a dopant formed of a halogenide and retains its infrared transmission property stably for a long time.

Abstract: A mechanism for cooling optical fibers which include optical fibers, metal netting wound around the fibers to conduct heat therefrom, and a sheath in which the fibers and netting are inserted. In accordance with one embodiment, the sheath and netting are spaced from each other so as to permit cooling air to flow therebetween to cool the fibers. In another embodiment, the netting is connected to a cooler by a heat connected element so that heat in the fibers is drawn to the cooler through the heat conductive element to cool the fibers.

Abstract: A construction for holding optical fibers, in which at least one of the ends of an optical fiber in a cable is a free end which is slidably and rotatively mounted to a hand piece at an end of the cable so as to prevent breakage of the optical fiber during bending of the cable.

Abstract: A focal point direct observation type laser scalpel device has a construction wherein laser beams generated by an infrared laser generator and transmitted through an optical fiber adapted for infrared laser beams and visible rays issued from a visible ray source and transmitted through optical fibers adapted for visible rays are passed through one common converging lens system so that recognition of the focal point of the laser beams is accomplished by visual observation of the focal point of the visible rays.

Abstract: A CO.sub.2 laser machining apparatus, has a CO.sub.2 laser oscillator connected with a condenser through a flexible cable including a fiber bundle for transmitting infrared rays of 10.6 micrometers therein.

Abstract: A safety device for a laser ray guide in which a laser ray-receiving element is installed on the input side of a lens of a laser ray guide including said lens, and troubles occurring in said laser ray guide can be detected by means of said laser ray-receiving element.

Abstract: A flexible cable suitably used as a jacket or cover for an inner conduit member such as a gas conduit or a liquid conduit, a signal transmission line, or an energy transmission line, or the like, which can provide safe use of the conduit inserted thereinto by limiting the bending radius thereof. The cable includes a plurality of axially symmetrical pipe members having large and small diameter ends which are assembled with the small ends of each pipe member fitted into the large end of an adjacent pipe member and loosely fitting flexible ring members fitted over the small ends of the pipe members.

Abstract: A preform is prepared to comprise a step index structure consisting of a core and a clad both made of metal halogenides or arsenic-selenium glass sparingly capable of transmitting infrared light of long wavelength and a layer of lubricant applied to the outer surface of the clad. The preform is set inside a metal cylinder. By pulling this metal cylinder through a plurality of dies containing orifices of successively decreased diameters at a temperature below the melting point, the preform can be elongated into an optical fiber of a prescribed diameter. The optical fiber thus produced is capable of transmitting infrared light of high power with a small loss. Protected and reinforced by the metal cylinder jacket, this fiber enjoys high mechanical strength.

Abstract: An optical fiber for infrared transmission constructed by winding a cladding around a core in the manner of a coil, the cladding having a refractive index lower than that of the core, a protective tube being employed to jacket the clad core.