US4822399A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Glass preform for dispersion shifted single mode optical fiber and method for the production of the same
Assignee: Sumitomo Electric Industries Ltd
•
Filing: 1987-06-10
•
Granted: 1989-04-18
•
Expires: 2007-06-10
Abstract
Abstract A glass preform for use in the fabrication of a dispersion shifted single mode optical fiber is produced by a method for comprising steps of inserting a core member consisting of an inner core part made of a germanium-added quartz glass which optionally contains fluorine and an outer core part made of a quartz glass having a refractive index smaller than that of the inner core part in a glass tube made of a fluorine-added quartz glass having a refractive index smaller than that of the outer core part, heating the core member and the glass tube to collapse the glass tube and fuse them together to produce a glass perform. The glass preform comprises a core member consisting of an inner core part made of GeO 2 -SiO 2 glass or GeO 2 -F-SiO 2 glass and an outer core part made of F-SiO 2 glass and a cladding made of F-SiO 2 glass and provides a dispersion shifted single mode optical fiber having reduced attenuation of light transmission in the 1.5 μm wavelength band.
Inventors
- 👤 Hiroo Kanamori
- 👤 Hiroshi Yokota
- 👤 Gotaro Tanaka
- 👤 Yoichi Ishiguro
- 👤 Masahiro Takagi
- 👤 Hiroshi Suganuma
- 👤 Masayuki Shigematsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:28
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/02; G02B6/02214; G02B6/02219; G02B6/02276; C; C03; C03B; C03B37/00; C03B37/01; C03B37/012; C03B37/01205; C03B37/01211; C03B37/014; C03B37/01446; C03B37/01466; C03B37/10; C03B37/12; C03C; C03C13/00; C03C13/04; C03C13/045; G02B6/036; G02B6/03616; G02B6/03622; G02B6/03633; C03B2201/00; C03B2201/06; C03B2201/08; C03B2201/12; C03B2203/00; C03B2203/10; C03B2203/22; C03B2203/36; Y; Y10; Y10S; Y10S65/00; Y10S65/15; Y10S65/16; Y10S65/90
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
300 words
A method for producing a glass preform for use in the fabrication of a dispersion shifted single mode optical fiber comprising steps of: preparing a core member by flame hydrolyzing glass forming raw materials to produce glass soot particles of SiO 2 containing GeO 2 , depositing glass soot particles on a starting member to form an inner core part, flame hydrolyzing glass raw materials to produce glass soot particles of SiO 2 , depositing the glass soot particles on the inner core part to form a soot core member consisting of the inner core part and an outer core part, dehydrating and sintering the soot core member to form a vitrified core member, and drawing the vitrified core member in an atmosphere not containing hydrogen atoms to produce an elongated core member, preparing a cladding member by flame hydrolysing glass forming raw material to produce glass soot particles of SiO 2 , depositing them on a starting member to form a soot glass rod, dehydrating the soot glass rod, heating it in an atmosphere containing a fluorine-containing compound, sintering the soot glass rod to form a vitrified glass rod, and boring a center part of the vitrified glass rod along its axis to form a tube shape cladding member, inserting the elongated core member consisting of the inner core part made of a germania-added quartz glass and the outer core part made of the quartz glass having a refractive index smaller than that of the inner core part in the tube shape cladding member made of the fluorine-added quartz glass having a refractive index smaller than that of the outer core part, and heating the core member and the tube shape cladding member to collapse the tube shape cladding member and fuse them together to produce a glass preform.
Claim 2
Independent Claim
300 words
A method for producing a glass preform for use in the fabrication of a dispersion shifted single mode optical fiber comprising steps of: preparing a core member by flame hydrolyzing glass forming raw materials to produce glass soot particles of SiO 2 containing GeO 2 , depositing glass soot particles on a starting member to form an inner core part, flame hydrolyzing glass raw materials to produce glass soot particles of SiO 2 , depositing the glass soot particles on the inner core part to form a soot core member consisting of the inner core part and an outer core part, dehydrating and sintering the soot core member to form a vitrified core member, and drawing the vitrified core member in an atmosphere not containing hydrogen atoms to produce an elongated core member, preparing a cladding member by flame hydrolysing glass forming raw material to produce glass soot particles of SiO 2 , depositing them on a starting member to form a soot glass rod, dehydrating the soot glass rod, heating it in an atmosphere containing a fluorine-containing compound, sintering the soot glass rod to form a vitrified glass rod, and boring a center part of the vitrified glass rod along its axis to form a tube shape cladding member, inserting the elongated core member consisting of the inner core part made of a germania-added quartz glass and the outer core part made of the quartz glass having a refractive index smaller than that of the inner core part in the tube shape cladding member made of the fluorine-added quartz glass having a refractive index smaller than that of the outer core part, and heating the core member and the tube shape cladding member to collapse the tube shape cladding member and fuse them together to produce a glass preform.
Claim 3
Dependent Claim
23 words
A method according to claim 1, wherein sintering of the soot core member is carried out in an atmosphere containing a fluorine-containing compound.
Claim 4
Dependent Claim
13 words
A method according to claim 1, wherein the germania-added glass further contains fluorine.
References Cited (Backward Citations)
US3933454A
Cited
US4165915A
Cited
GB2029400A
Cited
JPS5567533A
Cited
US4306767A
Cited
US4283213A
Cited
US4310339A
Cited
EP0154026A2
Cited
US4675038A
Cited
JPS5792536A
Cited
JPS596825A
Cited
EP0125828A1
Cited
US4629485A
Cited
EP0151438A2
Cited
US4620861A
Cited
JPH0654938A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-17 | 1992-10-17 | 1993-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-17 | 1996-10-17 | 1997-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-17 | 2000-10-17 | 2001-04-18 | $7700.00 | Window Closed / Lapsed |