Abstract: Optical components using a germania-silica glass are made by a gel technique. Tetra pentyloxygermane and a silicon alkoxide are hydrolyzed to form a gel, which is subsequently dried. Optical components, including optical fibers and devices, can be made using glass prepared by this technique.

Abstract: A cesium-containing optical glass comprising, by weight, 32-56% of SiO.sub.2, 6-25% of K.sub.2 O, 6-32% of Cs.sub.2 O, 0-30% of BaO, 0-2.5% of MgO, 5-34% of ZnO, 0-3% of ZrO.sub.2 and 0-5% of SnO.sub.2, provided that the total proportion of BaO, MgO and ZnO is 8-40% and the total proportion of ZrO.sub.2 and SnO.sub.2 is 0.2-6%. When this cesium-containing optical glass is treated in a molten bath containing potassium nitrate, the cesium ion in the glass is easily exchanged with a potassium ion and therefore, the cesium ion concentration gradually decreases radially outwardly from the central axis and the potassium ion concentration gradually increases in that direction. Thus, there is obtained a light converge-type lens in which the refractive index gradually decreases in the same direction.

Abstract: An acid-soluble glass used in manufacture of a flexible fiber optic bundle and a process for manufacturing a flexible fiber optic bundle using the glass. The glass has a composition expressed by mol percent comprising more than 15.0% and less than 41.0% of SiO.sub.2, more than 29.0% and less than 54.0% of B.sub.2 O.sub.3, more than 6.0% and less than 23.0% of BaO, and more than 5.0% and less than 19.0% of at least one alkali metal oxide selected from the group consisting of Na.sub.2 O, K.sub.2 O and Li.sub.2 O, the total amount of SiO.sub.2, B.sub.2 O.sub.3 and BaO being more than 71.0% and less than 80.0%.

Abstract: An acid-soluble glass for use in making a flexible optical fiber bundle, which comprises the following composition:20.0 mol %<SiO.sub.2 <48.0 mol %25.0 mol %<B.sub.2 O.sub.3 <50.0 mol %5.0 mol %.ltoreq.BaO.ltoreq.6.0 mol %7.0 mol %<Na.sub.2 O, K.sub.2 O, or Li.sub.2 O, or total of the two or more thereof<18.0 mol %71.0 mol %<SiO.sub.2 +B.sub.2 O.sub.3 +BaO<80.0 mol %7.4 mol %<ZnO<12.0 mol %1.8 mol %<Al.sub.2 O.sub.3 <7 mol %The acid-soluble glass exhibits a high solubility in an acid, a high resistance to water, and a high viscosity at the fiber-forming temperature.

Abstract: A range of alkali metal borosilicate glass compositions modified by the addition of alkaline earth metal oxides has been found to be especially suitable for the production of graded index optical fibre using the double crucible method. A core glass from this range may be paired with a suitable cladding glass, which may be another glass from the same range or an unmodified alkali metal borosilicate, so that in the nozzle of the double crucible thermal diffusion takes place to give a composition gradient of alkaline earth metal oxide and hence a refractive index gradient. The fibres thus obtained have better refractive index profiles if the proportions of the oxides in the core and cladding glasses are chosen so as to exclude a simple ion-exchange mechanism. Fibres having numerical apertures of up to 0.268 and best loss values as low as 5.0 dB/km have been prepared.

Abstract: Fluorozirconate glasses containing sodium fluoride and aluminum fluoride are used to improve an infrared transmitting fluoride glass optical wave guides thereby to obtain optical wave guides having high numerical aperture.

Abstract: A glass suitable for use as the core glass in a high numerical aperture optical fibre has a composition selected from the range of glasses which comprise(i) from 15 to 25 mole percent of soda,(ii) from 25 to 65 mole percent of silica and germania, taken together, the content of germania not exceeding 42 mole percent,(iii) up to 22.5 mole percent of boric oxide and barium oxide, taken together, the content of boric oxide not exceeding 20 mole percent, and the content of barium oxide not exceeding 12 mole percent, and(iv) from 0.01 to 1 weight percent of a redox buffering agent. The glass can be prepared by controlling the partial oxygen pressure of the melt so that it is approximately 10.sup.-5 atmospheres. An optical fibre can be produced, by using a soda-boro-silicate clad glass, and a core glass having the composition in the above range.

Abstract: An optical fiber of the graded index type consisting of a glass having predominantly the composition 60-70 mole % SiO.sub.2, 15-30 mole % alkali metal oxides, and 10 to 15 mole % MgO in combination with at least one oxide selected from the group formed by CaO, SrO, BaO and ZnO. The impurity content of the fiber is less than 0.01 ppm. In the fiber the MgO content increases from the axis of the fiber to the circumference of the fiber. The oxide or the other oxides, having cations which can be exchanged for the magnesium cation, decrease to a corresponding extent in this direction.

Abstract: An optical fiber with a graded index crystalline core (2,3) is made by filling a tube (1) with a mixture of two salts for which the one with the higher melting point has the lower refractive index. A graded composition results from partition effects when the fused salts are slowly cooled so that solidification proceeds uniformly inwardly from the tube wall. Fiber is pulled conventionally from the reesulting preform, and later is passed through a short hot zone to convert the core into single crystal form.

Abstract: 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.

Abstract: A silver halide glass is formed from silver iodide, silver fluoride and aluminum fluoride.

Abstract: An infrared ray-transmitting glass composition for optical fibers consisting essentially of 28 mol % to 38 mol % of BaF.sub.2, 2 mol % to 7 mol % of GdF.sub.3 and 58 mol % to 69 mol % of ZrF.sub.4, and optical fibers comprising said glass composition.

Abstract: Aluminum metaphosphate optical fibers are disclosed. In a specific embodiment, aluminum metaphosphate, doped with from 10 to 30 mole percent of diboron trioxide, is found to yield an optical fiber which combines the desirable properties of both high numerical aperture and low material dispersion. The fiber is nonhygroscopic and has a high melting temperature. The index of refraction of the glass may be lowered by doping with silicon dioxide. Consequently, a graded fiber may be made by increasing the concentration of silicon oxide from the core to the cladding.

Abstract: This invention provides a light-transmitting glass having superior weatherability which has the following composition in % by weight:______________________________________ SiO.sub.2 38-70 B.sub.2 O.sub.3 4-22 Na.sub.2 O 8-24 K.sub.2 O 0-15 Li.sub.2 O 0-15 Cs.sub.2 O 0-15 Al.sub.2 O.sub.3 1-22 ZnO 1-16 TiO.sub.2 0-7 ZrO.sub.2 0-7 CaO 0-7 BaO 0-7 MgO 0-7 ______________________________________provided that Na.sub.2 O+K.sub.2 O+Li.sub.2 O+Cs.sub.2 O is 13 to 24, and Al.sub.2 O.sub.3 +ZnO+TiO.sub.2 +ZrO.sub.2 +CaO+BaO+MgO is 2 to 32.The aforesaid multicomponent glass exhibits superior water resistance even when used as a covering ingredient of a light-transmitting glass fiber.

Abstract: A process is described for making a doped-silica ingot useful in the manufacture of optical fibers. At least a silicon compound and a titanium compound are decomposed in the flame of the induction plasma burner in the presence of a determined supply of hydrogen and are reacted with the oxygen contained in the burner feed gas and/or in the vector gas to form SiO.sub.2 and H.sub.2 O against a heat-stable support. As a result silica and titanium oxide are deposited on the support in the form of a homogeneous vitreous mass exhibiting a selected concentration of hydroxyl groups between 10 and 50 parts per million. Fluorine-doped silica is deposited radially in the same way on the resulting ingot. The resulting semifinished product is a cylinder consisting of a titanium-doped silica core, whose TiO.sub.2 concentration by weight is about 0.1 to 8%, covered by a sheath of fluorine-doped silica, whose fluorine concentration is about 0.1 to 3%.

Abstract: Glass for an optical fiber consists essentially of 10 to 64 mol % of at least one kind of fluoride selected from a first group consisting of CaF.sub.2, SrF.sub.2 and BaF.sub.2 ; 0.5 to 50 mol % of at least one kind of fluoride selected from a second group consisting of YF.sub.3 and fluorides of lanthanide elements; and 30 to 65 mol % of AlF.sub.3.

Abstract: In optical glass fibres formed of high-silica glass which is susceptible to the production of color centers on drawing into fibres, the attenuation due to such drawing-induced color centers is suppressed or reduced by incorporating from 1 to 100 (preferably 3 to 50) parts per million of cerium oxide in the glass from which the fibre is drawn, under oxidizing conditions such that a significant proportion of the cerium is in the form of ceric ions and the total attenuation is not more than 20 dB/Km in the wavelength range from 800 to 900 nm.

Abstract: Improved multicomponent fluorozirconate glasses, doped with chlorine, and a process for making them are disclosed that are continuously transmissive in the infrared spectrum.

Abstract: A potassium fluoro-borate glass, including silica and optionally alumina, containing at least 20 mole % potassium computed as K.sub.2 (O,F.sub.2), and wherein there are more fluorine atoms in the glass than oxygen atoms. The range of compositions includes low refractive index glasses, some with refractive indices less than that of silica, and high coefficient of thermal expansion glasses, some with coefficients matching those of aluminum, copper and brass.

Abstract: Glass for optical fibers is made of material of a binary system containing a fluoride selected from BaF.sub.2, SrF.sub.2 CaF.sub.2 and PbF.sub.2 and another fluoride selected from AlF.sub.3 and ZrF.sub.4.

Abstract: Aluminum metaphosphate optical fibers are disclosed. In a specific embodiment, aluminum metaphosphate, doped with from 10 to 30 mole percent of diboron trioxide, is found to yield an optical fiber which combines the desirable properties of both high numerical aperture and low material dispersion. The fiber is nonhygroscopic and has a high melting temperature. The index of refraction of the glass may be lowered by doping with silicon dioxide. Consequently, a graded fiber may be made by increasing the concentration of silicon oxide from the core to the cladding.