Global Patent Index - EP 1047641 A1

EP 1047641 A1 2000-11-02 - QUARTZ GLASS TUBE FOR USE IN THE PRODUCTION OF OPTICAL FIBER PREFORMS

Title (en)

QUARTZ GLASS TUBE FOR USE IN THE PRODUCTION OF OPTICAL FIBER PREFORMS

Title (de)

ROHR AUS QUARZGLASS FÜR DIE VERWENDUNG BEI DER HESTELLUNG VON VORFORMEN FÜR OPTISCHE FASERN

Title (fr)

TUBE EN VERRE DE SILICE DESTINE A LA PRODUCTION DE PREFORMES DE FIBRE OPTIQUE

Publication

EP 1047641 A1 (EN)

Application

EP 99963290 A

Priority

  • EP 9908539 W
  • JP 31789598 A
  • JP 913099 A

Abstract (en)

[origin: WO0027767A1] An object of the present invention is to provide a quartz glass tube for optical fiber preforms capable of producing optical fiber preforms having high dimensional precision, excellent distribution of refraction index, and yet free from degradation and the like of working environment. The object above is accomplished by a quartz glass tube for use in the production of optical fiber preforms, characterized in that the high temperature viscosity thereof is varied in the wall thickness direction, and that the high temperature viscosity in the inner layer side is lower than that of the outer layer side. It is shown how the viscosity and the refractive index are influenced by different doping agents to optimize producing parameters for the optical fiber preform and the distribution of refraction index of the optical fiber preform obtained. A method for producing an optical fiber preform comprising inserting a core glass rod into said quartz glass tube and melt welding them together is also disclosed.

IPC 1-7 (main, further and additional classification)

C03B 37/012

IPC 8 full level (invention and additional information)

C03B 37/012 (2006.01); C03C 13/04 (2006.01); G02B 6/00 (2006.01)

CPC (invention and additional information)

C03B 37/01211 (2013.01); C03B 37/01205 (2013.01); C03B 2201/04 (2013.01); C03B 2201/075 (2013.01); C03B 2201/12 (2013.01); C03B 2201/20 (2013.01); C03B 2201/28 (2013.01); C03B 2201/31 (2013.01)

Citation (search report)

See references of WO 0027767A1

Designated contracting state (EPC)

DE FI FR GB IT NL

EPO simple patent family

WO 0027767 A1 20000518; WO 0027767 B1 20000727; EP 1047641 A1 20001102; JP 2000203859 A 20000725; JP 4079204 B2 20080423; KR 100345358 B1 20020724; KR 20000035123 A 20000626

INPADOC legal status


2004-05-12 [RBV] DESIGNATED CONTRACTING STATES (CORRECTION):

- Ref Legal Event Code: RBV

- Designated State(s): DE FI FR GB IT NL

2003-08-06 [18W] WITHDRAWN

- Ref Legal Event Code: 18W

- Effective date: 20030605

2003-03-26 [17Q] FIRST EXAMINATION REPORT

- Ref Legal Event Code: 17Q

- Effective date: 20030207

2000-11-02 [17P] REQUEST FOR EXAMINATION FILED

- Ref Legal Event Code: 17P

- Effective date: 20000627

2000-11-02 [AK] DESIGNATED CONTRACTING STATES:

- Ref Legal Event Code: AK

- Designated State(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE