Optical glass and core material for optical fiber
AssigneeKabushiki Kaisha Ohara
InventorsMichiko Ogino, Masahiro Onozawa
Life of this patent
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Abstract
Provided is optical glass that does not contain lead, which is an environmental pollutant. The optical glass is ideal for the transmission of light even after being exposed to X-rays, and has a high refractive index. The optical glass comprises, by mass % in terms of oxide versus the glass total mass, 1.0% to 60.0% of an SiO2 component, and one or more selected from the group consisting of an La2O3 component, ZrO2 component, TiO2 component, Nb2O5 component, and Ta2O5 as essential components. The optical glass has a refractive index (nd) of 1.50 or greater, and has a light intensity recovery rate of 45% or greater when the glass having been irradiated with X-rays with a dose of 2.5 Gy is irradiated with light of a xenon lamp for 11 hours.
Claims14
An optical glass, comprising an SiO2 component of no less than 1.0% and no greater than 60.0% by mass percent based on total mass of the glass in terms of oxide composition,
- a La2O3 component content of greater than 4.0% and no greater than 15.0%,
- a ZrO2 component content of no less than 2.40% and no greater than 20.0%,
- a TiO2 component content of 0 to 5%,
- an Al2O3 component content of 0 to 0.14%,
- a MgO component content of 0 to 5.0%,
- a CaO component content of 0 to 7.0%,
- a SrO component content of 0 to 20.0%,
- a BaO component content of 0 to 40.0%,
- a ZnO component content of 0 to 20.0%,
- a B2O3 component content of 0 to 10.0%,
- a GeO2 component content of 0 to 15.0%,
- a WO3 component content of 0 to 15.0%,
- a Bi2O3 component content of 0 to 15.0%,
- a TeO2 component content of 0 to 15.0%,
- a Sb2O3 component content of 0 to 1.0%,
- substantially no lead compound,
- a total mass percentage of (Na2O+K2O) of no less than 0.1% and no greater than 8.79%,
- a total mass of a La2O3 component, a ZrO2 component, a TiO2 component, a Nb2O5 component and a Ta2O5 component is no less than 10.52% and no greater than 30.0% and
- having a refractive index (nd) of no less than 1.50, wherein a light intensity recovery rate is no less than 45% when the glass having been irradiated with X-rays with a dose of 2.5 Gy is irradiated with light of a xenon lamp for 11 hours.
Dependencies are inferred from the claim text.