Claims
- 1. A furnace for heating a glass rod comprising:
- a zirconia susceptor tube having an interior region for receiving said glass rod;
- a cylindrical silica beaker circumscribing said zirconia susceptor tube; and
- between said susceptor tube and said beaker an insulating region comprising magnesia grog.
- 2. A furnace according to claim 1 further comprising a magnesia tube disposed between said magnesia grog and said susceptor tube for holding said grog in place.
- 3. A furnace according to claim 2 wherein said magnesia tube is spaced from said susceptor tube.
- 4. A furnace according to claim 1 further comprising a layer of aluminosilicate insulator disposed between said beaker and said magnesia grog.
- 5. A furnace according to claim 1 further comprising an RF induction coil for heating said furnace.
- 6. A furnace according to claim 5 further comprising a metal shell substantially surrounding said RF induction coil for reducing radiation from said coil away from said furnace.
- 7. Apparatus for drawing glass fiber comprising:
- a preform feed mechanism for feeding a glass preform into a furnace;
- apparatus for drawing optical fiber from said furnace; and
- wherein said furnace has a furnace bore for receiving said preform and heating at least a portion of the preform to reflow temperature; said furnace comprising a zirconia susceptor tube, a cylindrical silica beaker circumscribing said susceptor, and between said susceptor and said beaker, an insulating region comprising magnesia grog.
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of application Ser. No. 08/443,510, filed on May 18, 1995, now abandoned.
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4450333 |
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Non-Patent Literature Citations (1)
Entry |
R.B. Runk, "A Zirconia Induction Furnace For Drawing Precision Silica Waveguides", Optical Fiber Transmission II Technical Digest (TuB5-1)(Feb. 22-24, 1977). |
Continuations (1)
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Number |
Date |
Country |
Parent |
443510 |
May 1995 |
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