Tokyo Shibaura Denki Kabushiki Kaisha

Kabushiki Kaisha Toshiba

Showa Electric Wire & Cable Co., Ltd.

Hironori Maki

Mituo Kasori

Takeshi Takano

Kenji Yagi

Hiroshi Imagawa

Naohiko Ogino

Kunihide Sawamura

Osamu Kokubo

A cladding glass for optical fiber comprises 60 to 80% by weight of silicon dioxide (SiO.sub.2), 0.5 to 10% by weight of aluminum oxide (Al.sub.2 O.sub.3), 9 to 17% by weight of an alkali metal oxide, 3 to 15% by weight of boron oxide (B.sub.2 O.sub.3) and more than 0 but not more than 3% by weight of fluorine (F). The cladding glass of this invention can simultaneously satisfy low refractive index and lowered viscosity, and is also excellent in water resistance and weathering resistance.

Cladding glass for optical fiber

There is provided a multi-component system glass fiber for optical communication which comprises a multi-component system glass for core having a composition comprising SiO.sub.2, BaO, Al.sub.2 O.sub.3, B.sub.2 O.sub.3, at least one alkali metal oxide selected from Na.sub.2 O, K.sub.2 O and Li.sub.2 O, MgO and CaO in amounts as specified in the specification and claims, and a multi-component system glass for clad layer having a composition comprising SiO.sub.2, Al.sub.2 O.sub.3, B.sub.2 O.sub.3, Na.sub.2 O, K.sub.2 O, Li.sub.2 O, at least one alkaline earth metal selected from MgO and CaO in amounts as specified in the specification and claims. The core in the glass fiber for optical communication according to the present invention shows lower optical loss and the clad layer shows high weathering resistance, and the glass fiber according to the present invention suffers from no devitrification during fiber drawing and is excellent in dimensional stability.

Multi-component glass optical fiber for optical communication

An optical fiber which consists of a multicomponent core glass member which is formed of SiO.sub.2, Al.sub.2 O.sub.3 and an alkali metal oxide and preferably contains CaO, MgO and B.sub.2 O.sub.3 ; and a multicomponent cladding glass member which is prepared from SiO.sub.2, Al.sub.2 O.sub.3, an alkali metal oxide and at least one component selected from the group consisting of ZnO, ZrO.sub.2 and TiO.sub.2, and preferably contains CaO, MgO and B.sub.2 O.sub.3 ; and consequently reduces transmission loss of light and exhibits prominent durability.

Optical fiber of high durability prepared from multicomponent glass

Growing community of inventors

Kawasaki, Japan

Hironori Maki