Abstract: In a glass processing method according to the invention, in the case of performing chemical vapor deposition or diameter shrinkage of a substrate glass tube G by relatively moving a heating furnace 20 comprising a heating element 21 for annularly enclosing the circumference of the substrate glass tube in a longitudinal direction of the substrate glass tube G with respect to the substrate glass tube G in which an outer diameter is 30 mm or more and a wall thickness is 3 mm or more and is less than 15 mm and an ovality of the outer diameter is 1.0% or less using a glass processing apparatus 1, a temperature of at least one of the heating element 21 and the substrate glass tube G is measured and the amount of heat generation of the heating element 21 is adjusted based on the measured temperature.

Abstract: In a glass processing method according to the invention, in the case of performing chemical vapor deposition or diameter shrinkage of a substrate glass tube G by relatively moving a heating furnace 20 comprising a heating element 21 for annularly enclosing the circumference of the substrate glass tube in a longitudinal direction of the substrate glass tube G with respect to the substrate glass tube G in which an outer diameter is 30 mm or more and a wall thickness is 3 mm or more and is less than 15 mm and an ovality of the outer diameter is 1.0% or less using a glass processing apparatus 1, a temperature of at least one of the heating element 21 and the substrate glass tube G is measured and the amount of heat generation of the heating element 21 is adjusted based on the measured temperature.

Abstract: In a glass processing method according to the invention, in the case of performing chemical vapor deposition or diameter shrinkage of a substrate glass tube G by relatively moving a heating furnace 20 comprising a heating element 21 for annularly enclosing the circumference of the substrate glass tube in a longitudinal direction of the substrate glass tube G with respect to the substrate glass tube G in which an outer diameter is 30 mm or more and a wall thickness is 3 mm or more and is less than 15 mm and an ovality of the outer diameter is 1.0% or less using a glass processing apparatus 1, a temperature of at least one of the heating element 21 and the substrate glass tube G is measured and the amount of heat generation of the heating element 21 is adjusted based on the measured temperature.

Abstract: In a glass processing method according to the invention, in the case of performing chemical vapor deposition or diameter shrinkage of a substrate glass tube G by relatively moving a heating furnace 20 comprising a heating element 21 for annularly enclosing the circumference of the substrate glass tube in a longitudinal direction of the substrate glass tube G with respect to the substrate glass tube G in which an outer diameter is 30 mm or more and a wall thickness is 3 mm or more and is less than 15 mm and an ovality of the outer diameter is 1.0% or less using a glass processing apparatus 1, a temperature of at least one of the heating element 21 and the substrate glass tube G is measured and the amount of heat generation of the heating element 21 is adjusted based on the measured temperature.

Abstract: In a glass processing method according to the invention, in the case of performing chemical vapor deposition or diameter shrinkage of a substrate glass tube G by relatively moving a heating furnace 20 comprising a heating element 21 for annularly enclosing the circumference of the substrate glass tube in a longitudinal direction of the substrate glass tube G with respect to the substrate glass tube G in which an outer diameter is 30 mm or more and a wall thickness is 3 mm or more and is less than 15 mm and an ovality of the outer diameter is 1.0% or less using a glass processing apparatus 1, a temperature of at least one of the heating element 21 and the substrate glass tube G is measured and the amount of heat generation of the heating element 21 is adjusted based on the measured temperature.

Abstract: A method produces a glass body that contains a reduced amount of OH groups in the metallic-oxide-containing glass layer and that has a reduced amount of transmission loss due to OH groups when the glass body is transformed into an optical fiber. The production method produces an optical glass body. An optical fiber contains the optical glass body in at least one part of its region for guiding a lightwave. The production method includes the following steps: (a) introducing into a glass pipe a gas containing an organometallic compound and a glass-forming material; (b) decomposing the organometallic compound into an organic constituent and a metallic constituent; (c) heating and oxidizing the metallic constituent so that produced glass particles containing a metallic oxide are deposited on the inner surface of the glass pipe to form a glass-particle-deposited layer; and (d) consolidating the deposited layer to form a metallic-oxide-containing glass layer.

Abstract: An apparatus can heat a glass body with high efficiency, and a method incorporating the apparatus produces an optical fiber preform. The apparatus has (a) a heating element that has a nearly cylindrical shape and that heats a glass body inserted into the heating element and (b) an infrared reflector that is placed at a position next to each of the openings of the heating element, that surrounds the glass body together with the heating element, and that has an inner surface having a spectral emissivity of at most 0.70 in a wavelength range of 4 to 12 ?m.

Abstract: A method produces a glass body that contains a reduced amount of OH groups in the metallic-oxide-containing glass layer and that has a reduced amount of transmission loss due to OH groups when the glass body is transformed into an optical fiber. The production method produces an optical glass body. An optical fiber contains the optical glass body in at least one part of its region for guiding a lightwave. The production method includes the following steps: (a) introducing into a glass pipe a gas containing an organometallic compound and a glass-forming material; (b) decomposing the organometallic compound into an organic constituent and a metallic constituent; (c) heating and oxidizing the metallic constituent so that produced glass particles containing a metallic oxide are deposited on the inner surface of the glass pipe to form a glass-particle-deposited layer; and (d) consolidating the deposited layer to form a metallic-oxide-containing glass layer.

Abstract: In a glass processing method according to the invention, in the case of performing chemical vapor deposition or diameter shrinkage of a substrate glass tube G by relatively moving a heating furnace 20 comprising a heating element 21 for annularly enclosing the circumference of the substrate glass tube in a longitudinal direction of the substrate glass tube G with respect to the substrate glass tube G in which an outer diameter is 30 mm or more and a wall thickness is 3 mm or more and is less than 15 mm and an ovality of the outer diameter is 1.0% or less using a glass processing apparatus 1, a temperature of at least one of the heating element 21 and the substrate glass tube G is measured and the amount of heat generation of the heating element 21 is adjusted based on the measured temperature.