摘要:
A process for producing an optical fibre glass preform. A burner is provided in the direction of a deposition target. The burner generates a first flame, a second flame surrounding the first flame and a third flame surrounding the first flame. The first flame is generated by feeding a substantial amount of a combustible gas together with a glass precursor material to a central duct of the burner.
摘要:
A method for fabricating a porous silica preform includes the steps of supplying fuel gas for generating an oxyhydrogen flame to a glass synthesizing burner; supplying Gas A containing silicon and Gas B containing fluorine to the burner; synthesizing glass particles; and depositing the glass particles around a starting rod, in which when glass particles are deposited directly on the starting rod, a supply of Gas A and a supply of Gas B supplied to the burner are adjusted so that a ratio of the number of fluorine atoms to the number of silicon atoms in the gas supplied to the burner satisfies the following Formula (1): {(number of F atoms)/(number of Si atoms)}≦0.1 (1)
摘要:
A flame stabilizing apparatus is disclosed for application to a burner for a flame hydrolysis deposition (FHD) process. In the flame stabilizing apparatus, a co-flow diffusion flame burner emits a flame onto a substrate and a flame stabilizer, installed around the burner coaxially, isolates the emitted flame from an instable ambient flow to stabilize the flame and a particle flow.
摘要:
An optical member includes a fused silica glass having a concentration of ≡SiH moiety below detection limit as measured by Raman spectroscopy and a concentration of molecular hydrogen of at least 1×1017 molecules/cm3. The fused silica glass exhibits an induced absorption level which quickly attains an initial peak upon exposure to irradiation and rapidly decays to a low value. The induced absorption level after decaying to the low value remains substantially unchanged by further irradiation.
摘要翻译:光学构件包括通过拉曼光谱测量的浓度= SiH部分低于检测限的熔融石英玻璃,并且分子氢浓度至少为1×10 17分子/ cm 3。 熔融石英玻璃表现出诱导吸收水平,其在暴露于照射时快速达到初始峰值并迅速衰变至低值。 通过进一步照射,衰减至低值后的诱导吸收水平基本上保持不变。
摘要:
A concentric multi-tubular burner for synthesizing glass particles having a center port group constituted by a combination of jet ports of raw material gas, combustible gas and oxygen gas, wherein an outer wall of the oxygen gas jet port in the center port group protrudes more toward a burner head than an inner wall of the oxygen gas jet port. The flow rate of oxygen gas jetted from the oxygen gas jet port of the center port group is controlled to be in a proper range.
摘要:
In a known method, a quartz glass preform is produced by supplying a glass-forming base material in liquid form to an injection nozzle of a multi-nozzle flame deposition burner, vaporizing or gasifying the liquid glass-forming base material in the deposition burner, mixing the vaporized or gasified glass-forming base material with a gas containing oxygen under creation of SiO.sub.2 particles in a chemical reaction, deposition of the SiO.sub.2 particles on a substrate under creation of a porous preform and sintering of the preform. In this method, expensive devices such as pumps and ultrasonic vaporizers are needed for the vaporization of the liquid glass-forming base material; in addition, these devices are subject to mechanical wear and chemical attack and furthermore, they require extensive maintenance and due to their size result in a great height of construction. In order to avoid these disadvantages, a method is proposed according to the invention wherein a gas for the creation of a mist is fed to the deposition burner for the vaporization or gasification of the glass-forming base material, resulting in the creation of a low pressure in the area of the injection nozzle orifice. In an apparatus suitable for implementing the method, a vaporizing device comprises a vaporizing nozzle for the supply of a vaporizing gas, said nozzle being located adjacent to the injection nozzle and having an opening which, as seen in the direction of travel of the vaporizing gas, extends in a plane behind the injection nozzle opening.
摘要:
A precision burner for oxidizing halide-free, silicon-containing compounds, such as, octamethylcyclotetrasiloxane (OMCTS), is provided. The burner includes a subassembly (13) which can be precisely mounted on a burner mounting block (107) through the use of an alignment stub (158), a raised face (162) on the burner mounting block (107), and a recess (160) in the back of the subassembly (13). The burner's face includes four concentric gas-emitting regions: a first central region (36, 90) from which exits a mixture of OMCTS and O.sub.2, a second innershield region (38, 92) from which exits N.sub.2, a third outershield region (40, 42, 94, 96) from which exits O.sub.2, and a fourth premix region (44, 98) from which exits a mixture of CH.sub.4 and O.sub.2. The burner provides more efficient utilization of halide-free, silicon-containing raw materials than prior burners.
摘要:
An improvement is proposed in the method for the flame hydrolysis of a silicon-containing gas, e.g., silicon tetrachloride, to produce fine silica particles to be deposited on a substrate in a process for the preparation of a silica glass preform of optical fibers by using a fivefold concentric multiplex-tube burner nozzle. In contrast to the conventional way for the flame hydrolysis in which the center or first nozzle opening of the burner serves for ejection of a mixture of silicon tetrachloride and oxygen and hydrogen is ejected from the third nozzle opening while argon is ejected from the second nozzle opening inbetween, the gas ejected from the second nozzle opening is, instead of argon alone, a mixture of oxygen and argon in a specified mixing proportion so that deposition of silica particles on the nozzle end can be prevented even when the feed rate of silicon tetrachloride is relatively high.
摘要:
An improved method for fabricating an optical fiber preform by the vapor phase axial deposition (VAD) method, comprises forming core and cladding soots at the same time by the use of core and cladding burners. The improvement is that the cladding burner is designed so that at least one of the outlets for a feed material gas, a fuel gas, an auxiliary fuel gas, and an inert gas is composed of a plurality of openings. In this improved method, the temperature distribution from the boundary of the core soot to the periphery of the cladding soot is made smooth, and thus the cladding soot is prevented from cracking.
摘要:
A torch for fabricating an optical fiber perform which has a plurality of raw gas injection passages at the center of the torch, a plurality of small-diameter combustion supporting gas injection passages independent of each other and disposed to surround the raw gas injection passages on the outer periphery of the raw gas injection passages disposed at the center of the torch, and an annular combustible gas injection passage disposed around the small-diameter combustion supporting gas injection passages. Thus, the torch can stably manufacture porous glass preforms.