1450123-A is referenced by 5 patents.

1450123 Optical glass fibres POST OFFICE 13 Nov 1974 [27 Nov 1973 29 Nov 1973] 30649/73 and 55388/73 Heading C1M In a dielectric optical fibre waveguide having a core region and a cladding region (e.g. of vitreous silica) the core region comprises glass consisting of between 90 and 99À9% of silica by weight and 0À1 and 10% by weight of Si x R y where R is an anion other than oxygen. Preferably R is nitrogen and x=3, y=4. As disclosed, a mixture of argon and silicon tetrachloride is fed to a mixing chamber 1 via pipe 5 and nitrogen via pipe 4, the streams being combined and adequately mixed by passage through silica wool 7 to a pipe 8 and thence to the induction coupled plasma discharge 11. Pipes 9 and 10 are concentric with pipe 8, pipe 9 initially carrying argon, then a mixture of argon and oxygen and pipe 10 oxygen, the exterior of pipe 10 being cooled by a water jacket.; The plasma torch is powered by radio frequency coupled to the plasma by coil 12. The resultant boule is condensed on to a rotating target. The boule is then heated to over 800 C. in an oxygen containing atmosphere to form a SiO 2 cladding, withdrawing into fibre form before or after heating. Alternative gas mixtures for making the doped silica are SiH 4 or SiCl 4 or Si 2 OCl 6 mixed with (1) NO+N 2 +NH 3 , (2) N 2 O+NH 3 + N 2 or (3) NH 3 +N 2 or Si(NR 1 R 2 ) x (OR 3 ) 4-x +N 2 +NH 3 (wherein R 1 , R 2 and R 3 are organic radicals).

Title
Doped vitreous silica
Application Number
GB19730030649 19731127
Publication Number
1450123 (A)
Application Date
November 27, 1973
Publication Date
September 22, 1976
Assignee
Post Office
IPC
C03C 17/02
C03C 03/06
C03C 13/00
H05H 01/26
H05H 01/00
G02B 06/02
G02B 06/00
C03C 13/00
C03C 04/00
C03C 03/06
C03C 03/04
C03B 37/018
C03B 37/014
B01J 19/08
H05H 01/30
H05H 01/00
G02B 06/02
G02B 06/00
C03C 13/04
C03C 04/16
C03C 03/06
C03C 03/04
C03B 37/018
C03B 37/014
B01J 19/08
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