Abstract: In a heating drawing, a base material glass plate is heated and softened in a heating furnace, and drawn to a desired thickness to form a glass strip. In the heating drawing, the base material glass plate is heated so that the base material glass plate has a U-shaped temperature distribution in a width direction. Such process can be realized through heating by a heating element which has a non-heating portion at a position opposite to a central portion of the base material glass plate in the width direction and a heating portion on both sides of the non-heating portion. Thus provided is a method of manufacturing a glass strip, the method includes heating and softening the base material glass plate, and drawing the base material glass plate to a desirable thickness to form a glass strip, and is capable of manufacturing a thin, rod-like glass strip with an excellent flatness.

Abstract: A manufacturing method of a glass strip, the method including a heating and drawing process of heating and softening a glass plate preform, drawing the glass plate preform to have a desired thickness, and forming a glass strip, wherein at the heating and drawing process, the glass plate preform is drawn so that an internal pressure of a heating furnace is kept positive relative to an atmospheric pressure and so that gas flows introduced to both surfaces of the glass plate preform, respectively are equal to each other within the heating furnace.

Abstract: Included are a reducing-heterogeneous-layer removing process of removing at least a part of a reducing heterogeneous layer in a surface of a plate glass manufactured through a float process, and a heating drawing process of heating and softening the plate glass from which at least the part of the reducing heterogeneous layer is removed in a heating furnace to draw the plate glass to a desirable thickness to form a glass strip. Thus provided is a method of manufacturing a glass strip capable of manufacturing a thin, rod-like glass strip with an excellent flatness even when a plate glass to be subjected to the heating drawing is a plate glass manufactured through the float process.

Abstract: A glass strip manufacturing method includes heat-drawing a preform glass plate by softening the preform glass plate with heat and drawing the preform glass plate down to a desired thickness. The preform glass plate has a level of transmittance that allows radiant heat absorbed therein while passing therethrough to diffuse before locally accumulating therein. The minimum transmittance of the preform glass plate in a thickness of 3 millimeters at a wavelength of 800 to 2200 nanometers is 86 to 95%.

Abstract: In a heating drawing, a base material glass plate is heated and softened in a heating furnace, and drawn to a desired thickness to form a glass strip. In the heating drawing, the base material glass plate is heated so that the base material glass plate has a U-shaped temperature distribution in a width direction. Such process can be realized through heating by a heating element which has a non-heating portion at a position opposite to a central portion of the base material glass plate in the width direction and a heating portion on both sides of the non-heating portion. Thus provided is a method of manufacturing a glass strip, the method includes heating and softening the base material glass plate, and drawing the base material glass plate to a desirable thickness to form a glass strip, and is capable of manufacturing a thin, rod-like glass strip with an excellent flatness.

Abstract: A manufacturing method of a glass strip, the method including a heating and drawing process of heating and softening a glass plate preform (1), drawing the glass plate preform to have a desired thickness and forming a glass strip (11), wherein at the heating and drawing process the glass plate preform (1) is drawn so that an internal pressure of a heating furnace (3) is kept positive relative to an atmospheric pressure and so that gas flows introduced to both surfaces of the glass plate preform (1) respectively are equal to each other within the heating furnace (3). It is possible to improve a surface roughness and obtain a desired surface roughness.

Abstract: An optical fiber drawing furnace capable of the prevention of entry of an ambient gas into an inner space thereof both effectively and economically, provided with a lower gas introduction portion through which inert gas is introduced into the inner space of the optical fiber drawing furnace, a chamber separated by a lower partition, and a bottom cover. The lower partition is arranged immediately below the lower gas introduction portion and has a first hole through which the chamber and the inner space are communicated. The bottom cover has a second hole through which the chamber and the atmosphere are communicated. An optical fiber is passed through the first and second holes. A controller detects a differential pressure between a pressure P1 in the inner space and a pressure P2 in the chamber and controls the suction flow by a pump for evacuating the gas in the chamber to maintain P1>P2.