| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 065424000 | Inert, nonoxidizing, or reducing environment | 9 |
| 20080282743 | Extended-Baking Process for Glass Deposition Tubes - 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. | 11-20-2008 |
| 20090038345 | APPARATUS FOR FABRICATING AN OPTICAL FIBER AND METHOD FOR SEALING A DRAWING FURNACE - In an apparatus for fabricating an optical fiber, the apparatus includes a drawing furnace provided with an insertion opening for receiving an optical fiber perform, a feed mechanism configured to support one end of the optical fiber preform so as to feed into the drawing furnace, a first sealing unit configured to seal a clearance gap between the optical fiber preform and the insertion opening, and a second sealing unit configured to seal a gap between the optical fiber preform and the first sealing unit when a tapered portion formed at the one end side of the optical fiber preform passes through the insertion opening. As a result, the available entirety of the optical fiber preform can be changed to an optical fiber, so that the cost for fabricating the optical fiber can be significantly reduced. | 02-12-2009 |
| 20090100876 | METHOD OF MANUFACTURING OPTICAL FIBER BASE MATERIAL AND APPARATUS OF THE SAME - 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. | 04-23-2009 |
| 20090211302 | METHOD OF MANUFACTURING OPTICAL FIBER BASE MATERIAL AND APPARATUS OF THE SAME - 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. | 08-27-2009 |
| 20100043497 | OPTICAL FIBER FOR WDM SYSTEM AND MANUFACTURING METHOD THEREOF - An optical fiber having a length of 1 km or more with average transmission loss in a wavelength band of 1383 nm being less than average transmission loss in a wavelength band of 1310 nm, wherein a maximum value of any 1 km section loss in the wavelength band of 1383 nm does not exceed the average transmission loss by 0.03 dB/km or more. | 02-25-2010 |
| 20110226020 | Glass-Tube Extended-Baking Process - 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. | 09-22-2011 |
| 20110265522 | OPTICAL FIBER MANUFACTURING APPARATUS AND OPTICAL FIBER MANUFACTURING METHOD - An optical fiber manufacturing apparatus including: a heating furnace in which an optical fiber is formed by melt-drawing an optical fiber preform; a sealing mechanism which is provided on an opening portion located at an upstream of the heating furnace and seals the heating furnace with an inert gas; a first pipe which is connected to the heating furnace and introduces the gas into the heating furnace; a second pipe which is connected to a lowermost compartment closest to the heating furnace among the compartments and introduces the gas into the lowermost compartment; and a gas flow rate control unit which controls a total sum of a flow rate of a gas supplied from the first pipe into the heating furnace and a flow rate of a gas supplied from the second pipe into the lowermost compartment to be substantially constant. | 11-03-2011 |
| 20110289979 | METHOD FOR PRODUCTING OPTICAL FIBER AT REDUCED PRESSURE - An optical fiber production system and method are provided for producing optical fiber. An optical fiber is drawn from a preform in a furnace and passes through a treatment device under a reduced pressure in the range of 0.01 to 0.80 atm. The treatment device cools the bare optical fiber as it cools to a temperature in the range of at least 1,600° C. to 1,300° C. A non-contact fiber centering device is located near an exit of the treatment device to provide centering of the optical fiber as it exits the treatment device. | 12-01-2011 |
| 20120000249 | METHOD FOR PRODUCING OPTICAL FIBER PREFORM - Provided is a method for producing an optical fiber preform including a dehydration step and a sintering step. In the dehydration step, a porous glass base material is provided to a furnace core tube of a dehydration-sintering furnace, and the porous glass base material is dehydrated using a dehydration agent added with an argon gas. In the sintering step, the porous glass base material dehydrated in the dehydration step is sintered. Further, in the dehydration step, a temperature of the porous glass base material begins to be increased in a condition such that a high heat conductivity gas, having a heat conductivity higher than a heat conductivity of the argon gas, is remaining inside the porous glass base material. | 01-05-2012 |
