Abstract:
To provide opaque quartz glass having no water absorbing properties and being excellent in infrared light shielding properties, and a method for its production. In the production of opaque quartz glass of the present invention, a fine amorphous silica powder and a pore forming agent are mixed, then molded and heated at a predetermined temperature, to obtain opaque quartz glass wherein contained pores are closed pores, the average pore size of pores is from 5 to 20 μm, and the content density of pores is high, whereby the heat shielding properties are high.
Abstract:
The present invention provides a silica container for pulling single crystal, the container having a straight body portion, a curved portion, and a bottom portion, wherein an outer side of the container is made of opaque silica glass containing bubbles, and an inner side of the container is made of transparent silica glass, and a mixed silica layer in which a phase in which a crystalline silica powder is fused and a phase in which an amorphous silica powder is fused are mixed in a granular texture is provided on at least an inner surface layer portion of the straight body portion. As a result, there is provided the silica container for pulling single crystal silicon which can suppress melt surface vibration of a silicon melt in the silica container at a high temperature.
Abstract:
The present invention is directed to a silica container for pulling single crystal silicon, the silica container including a straight body portion, a curved portion, and a bottom portion, wherein the outside of the silica container is made of opaque silica glass containing gaseous bubbles, the inside of the silica container is made of transparent silica glass containing substantially no gaseous bubble, and, on the inner surface of the bottom portion, a silica glass layer containing the OH group in a concentration of more than 300 ppm by mass but 3000 ppm by mass or less, the silica glass layer having a thickness of 20 μm or more but 1000 μm or less, is formed. As a result, a low-cost silica container for pulling single crystal silicon, the silica container that can reduce cavity defects called voids and pinholes in pulled single crystal silicon, is provided.
Abstract:
Disclosed is a method of heat treating quartz glass deposition tubes at between 900° C. and 1200° C. for at least 115 hours. The resulting deposition tubes are useful in forming optical preforms that can yield optical fibers having reduced added loss.
Abstract:
Disclosed is a method of heat treating quartz glass deposition tubes at between 900° C. and 1200° C. for at least 115 hours. The resulting deposition tubes are useful in forming optical preforms that can yield optical fibers having reduced added loss.
Abstract:
The invention relates to an optical fiber having an axial direction and a cross section perpendicular to said axial direction, and a method and preform for producing such an optical fiber. The optical fiber is adapted to guide light at a wavelength λ, and comprises a core region, an inner cladding region surrounding said core region, and at least one of a first type of feature comprising a void and a surrounding first silica material. The core, the inner cladding region and the first type of feature extends along said axial direction over at least a part of the length of the optical fiber. The first silica material has a first chlorine concentration of about 300 ppm or less.
Abstract:
Fused silica glass having an internal transmittance of UV with 245 nm wavelength, being at least 95% at 10 mm thickness, a OH content of not larger than 5 ppm, and a content of Li, Na, K, Mg, Ca and Cu each being smaller than 0.1 ppm. Preferably the glass has a viscosity coefficient at 1215° C. of at least 1011.5 Pa·s; and a Cu ion diffusion coefficient of not larger than 1×10−10 cm2/sec in a depth range of greater than 20 μm up to 100 μm, from the surface, when leaving to stand at 1050° C. in air for 24 hours. The glass is made by crystobalitizing powdery silica raw material; then, fusing the crystobalitized silica material in a non-reducing atmosphere. The glass exhibits a high transmittance of ultraviolet, visible and infrared rays, has high purity and heat resistance, and exhibits a reduced diffusion rate of metal impurities, therefore, it is suitable for various optical goods, semiconductor-production apparatus members, and liquid crystal display production apparatus members.
Abstract:
A method is provided for producing a vitreous silica crucible having excellent shape formability and fewer internal bubbles without excessively heating the curved portion and the bottom part. The method comprises arc melting a quartz powder molded product loaded in a rotating mold while performing vacuum suction, wherein the electrode is moved sideways with respect to the mold center line upon the initiation of arc melting or during the arc melting, and the arc melting is performed at an eccentric position, and preferably the time for total heating is limited to 60% or less of the total arc melting time. A vitreous silica crucible produced by this method is also provided.
Abstract:
A synthetic quartz glass for an optical member which is free from compaction and rarefaction is obtained. A synthetic quartz glass for an optical member to be used for an optical device employing a light having a wavelength of at most 400 nm and at least 170 nm as a light source, which contains substantially no oxygen excess defects, dissolved oxygen molecules nor reduction type defects, which has a chlorine concentration of at most 50 ppm and a OH group concentration of at most 100 ppm, and which contains oxygen deficient defects within a concentration range of at most 5×1014 defects/cm3 and at least 1×1013 defects/cm3. The fluorine concentration is preferably at most 100 ppm.
Abstract translation:得到不含压实和稀释的用于光学构件的合成石英玻璃。 用于光学元件的合成石英玻璃,其用于使用波长最多为400nm且至少170nm的光作为光源的光学元件,其基本上不含氧过剩缺陷,溶解氧分子或还原型 其浓度最多为50ppm,OH基浓度为100ppm以下,含有缺氧缺陷量为5×1014个/ cm 3以下且至少1×10 13个缺陷/ cm 3以下的缺陷缺陷。 氟浓度优选为100ppm以下。
Abstract:
Disclosed are high purity synthetic silica material having an internal transmission at 193 nm of at least 99.65%/cm and method of preparing such material. The material is also featured by a high compositional homogeneity in a plane transverse to the intended optical axis. The soot-to-glass process for making the material includes a step of consolidating the soot preform in the presence of H2O and/or O2.