摘要:
Apparatus (700) for sintering a glass base material (2) which is a base material for an optical fiber. The sintering apparatus (700) includes: a control unit which varies a condition for sintering the glass base material; and a furnace (12) which sinters the glass base material by heating the glass base material in an atmosphere of dehydration gas and inert gas. The control unit includes a drive source (3) which supplies the glass base material to the furnace at various speeds. The control unit includes a temperature control unit which controls the temperature of a heating source provided in the furnace.
摘要:
An apparatus for manufacturing a glass base material which is an parent material of an optical fiber, comprising: a tank which contains a raw material of the glass base material to vaporize the raw material to generate a raw material in gas phase; a temperature control unit which controls a temperature of the raw material; and a pressure control unit which controls the pressure of the raw material in gas phase.
摘要:
There are provided a sintering method and a sintering apparatus of a porous glass base material for sintering a porous glass base material to be dehydrated and vitrified into a transparent glass without causing core displacement and cross-sectional shape deformation. In detail, an aspect of the present invention is a sintering method of a porous glass base material for sintering a rod-like porous glass base material by hanging and moving the rod-like porous glass base material though a heating furnace. Here, the porous glass base material is lowered into a heating furnace heated to a sintering temperature, and after every part of the porous glass base material is moved through a preheated region extending from an upper edge of an insulating member to an upper edge of a heater in a heating furnace body in 4.5 hours or longer, the porous glass base material is sintered by the heater to be vitrified into a transparent glass.
摘要:
An improvement is proposed in the process for the preparation of a porous silica glass preform as a precursor of optical fibers by the VAD method, in which fine silica particles produced by the flame hydrolysis of a silicon-containing compound are deposited on the lower end of a seed rod suspended at the lower end of a suspender rod rotated by a carriage in a vertical tubular reactor furnace to grow in the vertical direction. Instead of taking the fully grown porous preform out of the tubular furnace by pulling up as suspended on the suspender rod as is undertaken in the prior art, the seed rod is temporarily held by clamping with a holding device with disconnection from the suspender rod and the porous preform and seed rod are pulled up by a separate vertical driving device so that the overall height of the apparatus can be greatly decreased contributing to a reduction of the manufacturing cost of optical fibers of silica glass.
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:
Proposed is an improvement in the VAD process for the preparation of a porous silica glass preform for double-core optical fibers by using three oxyhydrogen flame burners installed one above the other in a flame hydrolysis chamber in which a porous silica glass body consisting of the center core portion formed by the lowermost burner, side core portion formed by the middle burner and the cladding layer formed by the uppermost burner is gradually pulled up as it grows under rotation. Different from conventional procedures in which the extension of the nozzle axis of each of the burners intersects with the rotation axis of the growing body, the extension of the nozzle axis of the middle burner for the side core is displaced in a horizontal direction by a limited distance not to intersect nor to be in parallel with the rotation axis in the invention. By this means, an improvement is obtained in the uniformity of distribution of the refractive index in the side core which otherwise is remarkably disordered.
摘要:
An improvement is proposed in the apparatus and method for the preparation of a transparent silica glass preform as a precursor of optical fibers by sintering and vitrifying a porous silica glass preform in a sintering furnace as vertically suspended at the lower end of a suspender rod rotated by a carriage. Different from the conventional process in which the porous preform is lowered into the sintering furnace and the transparent preform after vitrification is pulled up out of the furnace as suspended at the lower end of the suspender rod throughout, a separate vertical driving device is provided along with a horizontal driving device for the carriage so that the effective up-and-down stroke of the carriage can be greatly reduced and the apparatus as a whole can be by far more compact contributing to the reduction of the manufacturing costs of the optical fibers of silica glass.
摘要:
When transmitting serial data from a master device to a slave device, it is possible to promptly detect a communication error if any occurs. Serial data transmitted from the master device to the slave device has two or more continuous bytes of dummy data having an identical structure. When the slave device recognizes the dummy data, communication error processing is executed. Assume that the serial data is shifted by an affect of a noise. In this case, “a text end control code (ETX)” is also shifted and the serial data cannot be recognized and no data reception end process is executed. However, during a period after this, a part of the first dummy data and a part of the second dummy data are received and one dummy data is recognized. Thus, the slave device can promptly execute the communication error processing.
摘要:
A method of manufacturing an optical fiber base material includes: forming a porous glass base material by depositing glass particles; providing a vessel which employs a composite tube, the composite tube including a portion formed by jacketing a first quartz glass containing aluminum equal to or less than 0.01 ppm with a second quartz glass containing aluminum equal to or more than 15 ppm; introducing dehydration reaction gas and inert gas into the vessel; heating the jacketed portion in the vessel which contains the dehydration reaction gas and the inert gas; and inserting the porous glass base material into the heated vessel to dehydrate and sinter the porous glass base material.
摘要:
A method of manufacturing an optical fiber base material includes: forming a porous glass base material by depositing glass particles; providing a synthetic quartz glass vessel at least partly made of quartz glass which contains aluminum equal to or less than 0.01 ppm; introducing dehydration reaction gas and inert gas into the vessel; heating a portion made of quartz glass which contains aluminum equal to or less than 0.01 ppm in the vessel that contains the dehydration reaction gas and the inert gas; and inserting the porous glass base material into the heated vessel to dehydrate and sinter the porous glass base material.