Opaque silica composition

Ophthalmic and optical glass

Ophthalmic and optical glasses

Ophthalmic glass of high refractive index

Ophthalmic glasses with high indices of refraction

Optical amplifier glass

Optical amplifying glass

Optical amplifying glass and method for its production

Optical and ophthalmic glass with refractive indices greater tha

Optical and ophthalmic glass with refractive indices greater tha

Optical and ophthalmic glass with refractive indices nd>1.58,

Optical and ophthalmic glasses

Optical CdO and ThO.sub.2 -free glass with refractive indices of

Optical colored and filter glass

Optical colored glass, its use, and an optical long-pass...

Optical colored glass, its use, and an optical long-pass...

Optical colored glasses

Optical crown glass having negative anomalous partial dispersion

Optical elements made from ThF.sub.4 --BeF.sub.2 glasses

Optical fiber amplifier and a glass therefor