Abstract: A light polarizing glass article comprising a base glass and metallic copper particles dispersed in said base glass wherein said metallic copper particles have aspect ratios in the range of from about 2:1 to 15:1 and said base glass is selected from the group consisting of silicate, borosilicate, borate and phosphate glasses which contain at least one reductant element. The article is prepared by heating a batch of glass containing copper and halogen containing constituents to develop copper halide particles in the glass, elongating said glass containing copper halide particles at a temperature where said glass exhibits a viscosity of from 1×108 to 1×1011 poises, and reducing at least a portion of the copper halide particles in the elongated glass to produce metallic copper particles therein. An optical isolator employing the above light polarizing glass articles is also provided.

Abstract: Disclosed is disc substrate consisting of SiO2—Al2O3—RO (RO=divalent metal) glasses having high specific elastic modulus of 36×106 Nm/kg or more or high Young's modulus of 110 GPa or more, high transition temperature of 700° C. or higher (high heat resistance), excellent surface smoothness (surface roughness Ra<5 Å) and high strength. The substrates exhibiting high specific elastic modulus or high Young's modulus and high strength enables to realize thinner magnetic discs and prevent breakdown of magnetic discs. Since glass substrates being composed of the glass have excellent heat resistance and flatness, the substrates can be subjected to heat treatment for improvement of magnetic layer characteristics and realize smaller flying height of magnetic head, i.e., higher recording density.

Abstract: In a glass substrate for use in an information recording medium which is specified by Young's modulus E, the Young's modulus E is determined by the following equation (1) so that the Young's modulus exceeds 90, E=&Sgr;xi&rgr;i&Sgr;xisi  (1) where Si=2NA(Gi/M) (4&pgr;/3) (mRA3+nRO3), &rgr;i is the density of component i, NA is the Avogadro's number, Gi is dissociation energy of the component i, Mi is molecular weight of the component i, RA and RO is ionic radius of cation A and anion O of the component i defined by AmOn.

Abstract: The present invention relates to a process for producing a titanium oxide thin film, said process comprises soaking a substrate in an aqueous solution containing 10.sup.-9 to 9.times.10.sup.-2 mol/L of a titanium fluoro complex compound in the presence of a fluoride ion capturing agent to form a titanium oxide thin film on the surface of the substrate; and a photocatalyst comprising the titanium oxide thin film thus produced; and can provide a simple process for the formation of a highly homogeneous titanium oxide thin film which is fast and corrosion resistant, and has a high refractive index and a catalytic activity for the photoreaction.

Abstract: A material according to the invention is made of a glass whose transition temperature is 750 degrees Celsius or greater and used for a substrate for information recording media, and for example, the glass has an essential component made of any group chosen from SiO.sub.2 --Al.sub.2 O.sub.3 --MgO--CaO, SiO.sub.2 --Al.sub.2 O.sub.3 --MgO--Y.sub.2 O.sub.3, SiO.sub.2 --Al.sub.2 O.sub.3 --CaO--Y.sub.2 O.sub.3, SiO.sub.2 --Al.sub.2 O.sub.3 --MgO--CaO--Y.sub.2 O.sub.3, and SiO.sub.2 --Al.sub.2 O.sub.3 --M.sub.2 O.sub.3 (wherein M denotes a trivalent metal.). This material can form a substrate for information recording media, or more specifically, a substrate on which at least a magnetic layer is formed to constitute a magnetic disc.

Abstract: A method for seeking, from an outer circle radius a, an inner circle radius b, and a thickness h of a disc substrate and a deflection Wmax permissive at a time of rotation, a specific elastic modulus G that a material forming the substrate has, ##EQU1## The material for providing a substrate for information recording media having a thickness h of 0.6 millimeter and a deflection Wmax of 1.4 micrometer has a specific elastic modulus G satisfying above Formula (1).

Abstract: Disclosed are an optical fiber comprising a core and a cladding wherein the core is composed of a In-Ga-Cd-Pb halide glass and the clad composed of a halide glass possesses a refractive index of 1.515 or less, which has a large specific refractive index difference (.DELTA.n) and a large numerical aperture, and such an optical fiber as mentioned above wherein the core contains one or more activating ions as well as an optical fiber amplifier comprising a pumping source, a laser glass fiber and a means for introducing pumping light and signal light into the above laser glass fiber, wherein the laser glass fiber is the optical fiber of the present invention mentioned above.

Abstract: Disclosed are laser glasses composed of a Ga--Na--S glasses doped with one or more kinds of activating ions, laser glass fibers comprising a core and a clad wherein the core is composed of the above-mentioned laser glasses of the present invention and optical fiber amplifiers comprising a pumping source, a laser glass fiber and a means for introducing pumping light and signal light into the laser glass fiber wherein the laser glass fiber is the above-mentioned laser glass fiber of the present invention. The laser glasses of the present invention show high radiative quantum efficiency and host glass stability and can be produced easily.

Abstract: Faraday rotation glass having a practically sufficiently large Verdet's constant, which contains 60 to 75 mol % of P.sub.2 O.sub.5, 10 to 20 mol % of Tb.sub.2 O.sub.3 and 10 to 25 mol % of K.sub.2 O and having substantially no platinum inclusion.

Abstract: A phosphate based laser glass composition for high average power systems including by mol percent 60-66% P.sub.2 O.sub.5, 6-9% Al.sub.2 O.sub.3, 8-12% Li.sub.2 O, 0-15% MgO, 0-15% ZnO, 0-5% B.sub.2 O.sub.3 and 0.1-4%, Nd.sub.2 O.sub.3, with MgO+ZnO totaling 14-16%.

Abstract: Processes in which glass parts are strengthened by ion exchange with cations in a molten salt bath are improved by removal of the small amounts of moisture and other forms of the hydroxyl group present in the salt melt by either chemical or electrolytic means, prior to the ion exchange. The chemical means involve reacting the hydroxyl-containing compounds with the chlorine-containing gas, while the electrolytic means involve electrolysis to gaseous hydrogen and oxygen. Preferred embodiments further include a gas purge prior to the chemical or electrolytic treatment.

Abstract: An antireflective coating and a process for producing the same are described. This antireflective coating has the difference in refractive index between the glass interface and the outer surface of the antireflected coating of 0.15 or less. This antireflective coating can be formed by treating a glass with an aqueous solution containing specified amounts of an acidic salt, Al.sup.3+ and Si.sup.4+. The antireflective coating has a high mechanical strength and optical elements having such an antireflective coating are useful for use in the laser nuclear fusion system.

Abstract: A method of increasing the thermal shock resistance of a phosphate laser glass is described, comprising coating the surface of the glass with a sol solution which is prepared by hydrolyzing at least one organometallic compound dissolved in an organic solvent and then partially polycondensing, and then heat-treating to form a glassy coating on the surface of the glass. The phosphate laser glass having such increased thermal shock resistance is useful for high repetitive operation.

Abstract: A glass for edge-cladding a disc laser glass, comprising, in mol%, followed in parentheses by wt % value,______________________________________ P.sub.2 O.sub.5 46- 63, (64-76) Al.sub.2 O.sub.3 4- 8, (3.5-7.5) B.sub.2 O.sub.3 0- 5, (0-3.0) K.sub.2 O 2- 20, (2.5-16.5) Na.sub.2 O 0- 15, (0-8.5) Li.sub.2 O 0- 14, (0-3.5) K.sub.2 O + Na.sub.2 O + Li.sub.2 O 18- 30, (11.5-20.5) CuO 2- 20, (1.4-13.5) ZnO 0- 15, (0-11.5) MgO 0- 5, (0-2.0) and CuO + ZnO + MgO 7- 20. (4.7-13.5).

Abstract: A phosphate optical glass, whose length of the light path is substantially independent of temperature, comprising, in % by weight,______________________________________ P.sub.2 O.sub.5 27 - 55 K.sub.2 O 6 - 26 BaO 10 - 50 K.sub.2 O + BaO larger than 35 Al.sub.2 O.sub.3 2 - 15 TiO.sub.2 + Nb.sub.2 O.sub.5 + Ta.sub.2 O.sub.5 4 - 20 TiO.sub.2 0 - 14 Nb.sub.2 O.sub.5 0 - 20 Ta.sub.2 O.sub.5 0 - 7 B.sub.2 O.sub.3 0 - 5 Li.sub.2 O 0 - 2 Na.sub.2 O 0 - 5 MgO 0 - 6 CaO 0 - 8 SrO 0 - 10 ZnO 0 - 10 PbO 0 - 13, and As.sub.2 O.sub.3 0 - 2 .