Abstract: The present invention is directed to an electroconductive silver thick film paste composition comprising Ag, a glass frit and rhodium resinate, Cr2O3 or a mixture thereof all dispersed in an organic medium. The present invention is further directed to an electrode formed from the paste composition and a semiconductor device and, in particular, a solar cell comprising such an electrode. The paste is particularly useful for forming a tabbing electrode.

Abstract: An optical glass includes, in weight percent: 15% to 36% of SiO2; 13% to 31% of B2O3; 4% to 27% of Al2O3; 0% to 19% of Ta2O5; 0% to 10% of ZrO2; and 0% to 10% of Nb2O5; wherein Ta2O5+Nb2O5+ZrO2?7.1%; and has optical constants including a refractive index nd between 1.54 and less than 1.61 and an Abbe number vd in the range of 50 to 57; and wherein ?Pgy that denotes the anomalous dispersion is ?0.004 or less.

Abstract: An optical Glass characterized by comprising, denoted as molar percentages: B2O5—5 to 45 percent; SiO2—0 to 6 percent (excluding 6 percent); Li2O, Na2O, K2O in total—0 to 3 percent; ZnO—10 to 40 percent; La2O3. 5 to 30 percent; Gd2O3—1 to 20 percent; and ZrO2, TaO2, TiO2, Nb2O5, WO3, and Bi2O3 in total—2.5 to 20 percent. The cation ratio of the Ti4+ content relative to the total content of Zr4+, Ta5+, Ti4+, Nb5+, W6+, and Bi3+ is 0.30 or lower; in that the temperature Tp at which a viscosity of 107.2 dPa·s is exhibited is 706° C. or lower. The refractive index nd and the Abbé number v(nu)d satisfy all of the following relations (I) to (IV): 34.0?vd<40 (I); nd?1.87 (II); nd?2.245?0.01×vd (III) and nd?2.28?0.01×vd (IV).

Abstract: The invention includes a composition for sealing agent, generally in the form of glass frit, lead-free, comprising by weight over the total weight of the composition: 30-80% Bi2O3; 2-10% ZnO; 2-10% B2O3; 0-5% Na2O; 1-10% SiO2; 1-8% Al2O3; 0-7% BaO; and 0-8% MgO. The composition for sealing agent as defined above can be added with a filler in a quantity up to 20% by weight over the total weight of the resulting mixture. The invention also includes a sealing paste containing the composition for sealing agent, the optional filler, an organic binder and optionally an organic solvent. The invention also includes methods for producing and using the composition for sealing agent and the sealing paste, as well as an electronic device sealed with the sealing paste.

Abstract: The present invention relates to an optical glass including, in terms of mass % on the basis of oxides, B2O3: 10% to 20%, SiO2: 0.5% to 12%, ZnO: 5% to 19%, Ta2O5: 3% to 17%, Li2O: 0.2% to 3%, ZrO2: 0.6% to 4.9%, WO3: 6.1% to 20%, La2O3: 32.5% to 50%, and Y2O3: 0.2% or more and less than 1.5%, in which a mass fraction (La2O3/Y2O3) of a content of La2O3 to a content of Y2O3 in terms of mass % is 40 or higher, and the optical glass has optical constants of a refractive index nd of 1.83 to 1.88 and an Abbe's number ?d of 39 to 42.

Abstract: An aspect of the present invention relates to optical glass, which is oxide glass comprising various cationic components in prescribed amounts without Pb, with a refractive index nd of 1.750 to 1.850, an Abbé number ?d of 29.0 to 40.0, and a glass transition temperature of less than 630° C.

Abstract: A high-refractivity low-dispersion optical glass of which the Ta2O5 content is suppressed is provided, the optical glass comprising, by mass %, 1 to 30% of B2O3, 0.1 to 20% of SiO2, 55 to 75% of a total of La2O3, Gd2O3, Y2O3 and Yb2O3, the content of La2O3 being 15 to 55%, the mass ratio of the content of Gd2O3 to the total content of La2O3, Gd2O3, Y2O3 and Yb2O3, Gd2O3/La2O3+Gd2O3+Y2O3+Yb2O3), being 0.17 to 0.65, 0 to 13% of Ta2O5 (exclusive of 13%), and 0 to 25% of a total of Nb2O5, TiO2, WO3 and ZrO2, the content of Nb2O5 being less than 10%, and having a refractive index nd of 1.83 to 1.92 and an Abbe's number ?d of 36 to 45.

Abstract: Thin glasses having high refractive index (nd), a layer composite assembly made from these thin glasses, a method for the production of the thin glasses, and the uses of the thin glasses are provided. The thin glasses are processed in an in line manufacturing process and have the optical properties of a classical optical glass. The thin glasses are highly transparent, crystallization-resistant, chemically resistant and highly refractive. The viscosity/temperature behavior of the thin glasses is adjusted to the manufacturing process via in line flat glass methods.

Abstract: An optical glass, comprising, denoted as cation percentages: a content of Si4+ and B3+ (35 to 55); a combined content of La3+, Gd3+, and Y3+ (30 to 55), wherein Gd3+ is 5 to 20%; a content of Ti4+, Nb5+, Ta5+ and W6+ (7 to 20); Zr4+ (2 to 8); and Zn2+ (0 to 10); wherein a cation ratio of Zn2+ to Gd3+ is 0 to 0.80; a cation ratio of Gd3+ to Ti4+, Nb5+, Ta5+, and W6+ combined is 0.65 to 2.00; a cation ratio of Ta5+ to Ti4+, Nb5+, Ta5+, and W6+ combined is 0 to 0.30; a cation ratio of Ti4+ to Ti4+, Nb5+, Ta5+, and W6+ combined is 0.30 to 0.90; and a refractive index nd is 1.890 to 1.950, and an Abbé number ?d of equal to or lower than 39.0, the Abbé number ?d satisfying a relation of ?d?(2.334?nd)/0.012 relative to nd.

Abstract: An optical glass comprising, by mass %, 12 to 40% of SiO2, 15% or more but less than 42% of Nb2O5, 2% or more but less than 18% of TiO2, (provided that Nb2O5/TiO2 is over 0.6), 0.1 to 20% of Li2O, 0.1 to 15% of Na2O, and 0.1 to 25% of K2O, and having an Abbe's number ?d of 20 to 30, a ?Pg,F of 0.016 or less and a liquidus temperature of 1,200° C. or lower.

Abstract: The invention discloses an optical glass and an optical element. The optical glass comprises 0.1 wt % -8 wt % of SiO2, 20 wt % -32 wt % of B2O3, 20 wt % -35 wt % of La2O3, 15 wt % -30 wt % of Gd2O3, 1-6 wt % of Ta2O5, 1 wt % -15 wt % of ZnO, and 0.1 wt % -2 wt % of Li2O. The optical glass claimed in the invention has a refractive index of 1.75-1.8, an Abbe number of 45-52, a transformation temperature of less than 610° C., and a wavelength of less than 390 nm at 80% transmittance. Thus the claimed optical glass meets the requirements for a modern imaging device.

Abstract: A method of bonding a first substrate to a second substrate includes providing a glass, applying the glass in a layer between the first and second substrates to form an assembly, and heating the assembly to a bonding temperature above a glass transition temperature of the devitrifying glass, selected to cause the glass to bond the first substrate to the second substrate. The devitrifying glass has constituents that include various amounts of group A in a molar concentration of 70-95%, group B in a molar concentration of 5-20%, group C in a molar concentration of 1-20%, group D in a molar concentration of 0-6%; and group E in a molar concentration of 0-10%. The group A, B, C, D and E groups are disclosed herein.

Abstract: An optical glass having a refractive index nd of 1.70 or greater and an Abbé number of 50 or greater. Given as mole percentages, it comprises: B2O3 (20 to 80 percent), SiO2 (0 to 30 percent), Li2O (1 to 25 percent), ZnO (0 to 20 percent), La2O3 (4 to 30 percent), Gd2O3 (1 to 25 percent), Y2O3 (0 to 20 percent), ZrO2 (0 to 5 percent), MgO (0 to 25 percent), CaO (0 to 15 percent), and SrO (0 to 10 percent), with the combined quantity of the above components being 97 percent or greater. The molar ratio of {ZnO/(La2O3+Gd2O3+Y2O3)} is 0.8 or less and the molar ratio of {(CaO+SrO+BaO)/(La2O3+Gd2O3+Y2O3)} is 0.8 or less. Ta2O5 may be incorporated as an optional component, with the molar ratio {(ZrO2+Ta2O5)/(La2O3+Gd2O3+Y2O3)} being 0.4 or less.

Abstract: An optical glass having high-refractivity and low-dispersion properties and containing, by mol %, 0.1 to 40% of SiO2, 10 to 50% of B2O3, wherein the mass ratio of the content of SiO2 to the content of B2O3, SiO2/B2O3, is 1 or less, 0.5 to 22% of ZnO, 5 to 50% of La2O3, and optionally other ingredients. The optical glass has a refractive index nd of 1.86 to 1.95 and an Abbe's number ?d of (2.36?nd)/0.014 or more but less than 38, and a glass transition temperature of equal to or greater than 640° C.

Abstract: A high-refractivity low-dispersion optical glass that can be stably supplied and has excellent glass stability and that has coloring reduced, composed of in mass %, 5 to 32% of total of SiO2 and B2O2, 45 to 65% of total of La2O2, Gd2O2 and Y2O2, 0.5 to 10% of ZnO, 1 to 20% of total of TiO2 and Nb2O5, and optionally other components. The optical glass has a refractive index nd of 1.89 to 2.0, an Abbe's number ?d of 32 to 38 and a coloring degree ?70 of 430 nm or less.

Abstract: An optical glass that is an oxide glass having a very high refractive index in spite of its low-dispersion property, having excellent glass stability and having less susceptibility to coloring.

Abstract: An optical glass having optical constants of a refractive index (nd) of 1.78 or over, an Abbe number (?d) of 30 or below, and a partial dispersion ratio (?g, F) of 0.620 or below comprises SiO2 and Nb2O5 as essential components, wherein an amount of Nb2O5 in mass % is more than 40%. The optical glass further comprising, in mass % on oxide basis, less than 2% of K2O and one or more oxides selected from the group consisting of B2O3, TiO2, ZrO2, WO3, ZnO, SrO, Li2O and Na2O wherein a total amount of SiO2, B2O3, TiO2, ZrO2, Nb2O5, WO3, ZnO, SrO, Li2O and Na2O is more than 90% and TiO2/(ZrO2+Nb2O5) is less than 0.32.

Abstract: The present invention provides a lead-free glass for semiconductor encapsulation, which can encapsulate semiconductor devices at a low temperature, has an excellent acid durability and hardly precipitates crystals when forming a glass tube, and an encapsulator for semiconductor encapsulation made of the glass. The glass comprises, as a glass composition, from 45 to 58% of SiO2, from 0 to 6% of Al2O3, from 14.5 to 30% of B2O3, from 0 to 3% of MgO, from 0 to 3% of CaO, from 4.2 to 14.2% of ZnO, from 5 to 12% of Li2O, from 0 to 15% of Na2O, from 0 to 7% of K2O, from 15 to 30% of Li2O+Na2O+K2O, and from 0.1 to 8% of TiO2, in terms of % by mol, wherein a ratio of ZnO to Li2O is in the range from 0.84 to 2.

Abstract: The present invention relates to an optical glass having a refractive index nd of 1.86 or higher and an Abbé number v(nu)d of 28 to 36; a preform for precision press molding and an optical element that are comprised of this glass; and a method for manufacturing the optical element.

Abstract: The present invention relates to an optical glass with a refractive index nd of 1.89 or higher and an Abbé number v(nu)d of 28 to 36; a preform for precision press molding and an optical element that are comprised of this glass; and a method for manufacturing the optical element.

Abstract: The present invention relates to an optical glass with a high refractive index and good precision press moldability, and a preform for precision press molding and an optical element that are comprised of the optical glass. The present invention further relates to a method of manufacturing an optical element, a lens unit being equipped with an optical element and an image pickup device being equipped with a lens unit.

Abstract: [Problems to be Solved] To provide a high-refractivity low-dispersion optical glass that enables the stable production of high-quality optical elements. [Means to Solve the Problems] An optical glass comprising, as essential components, 20 to 50% of B3+, 5 to 35% of La3+, 1 to 30% of Nb5+, 0.5 to 15% of Ta5+, and 11 to 40% of Zn2+, the total content of B3+ and Si4+ being 20 to 50%, the total content of La3+, Gd3+ and Y3+ being 5 to 35%, the cationic ratio of ((B3++Si4+)/(La3++Gd3++Y3+)) being from 1 to 5, the total content of Ti4+, Nb5+, Ta5+ and W6+ being 10 to 35%, the cationic ratio of ((Nb5++Ta5+)/(Ti4++Nb5++Ta5++W6+)) being from 0.7 to 1, the cationic ratio of ((B3++Si4+)/(Ti4++Nb5++Ta5++W6+)) being from 0.5 to 4, the cationic ratio of ((La3++Gd3++Y3+)/(Ti4++Nb5++Ta5++W6+)) being from 0.2 to 3, the cationic ratio of Zn2+/Zn2++Mg2++Ca2++Sr2++Ba2+) being from 0.8 to 1, the optical glass having a refractive index nd of 1.89 or more and an Abbe's number ?d of 27 to 37.

Abstract: An optical glass comprising, by mass %, 12 to 30% of total of B2O3 and SiO2, 55 to 80% of total of La2O3, Gd2O3, Y2O3, Yb2O3, ZrO2, Nb2O5 and WO3, 2 to 10% of ZrO2, 0 to 15% of Nb2O5, 0 to 15% of ZnO and 0% or more but less than 13% of Ta2O5, wherein the ratio of the content of Ta2O5 to the total content of La2O3, Gd2O3, Y2O3, Yb2O3, ZrO2, Nb2O5 and WO3 is 0.23 or less, the ratio of the total content of La2O3, Gd2O3, Y2O3 and Yb2O3 to the total content of B2O3 and SiO2 is from 2 to 4, the optical glass having a refractive index nd of 1.86 or more and an Abbe's number ?d of 38 or more, and a rod-shaped glass shaped material and an optical element formed of the above optical glass each.

Abstract: A glass composition for electrode formation includes, as a glass composition expressed in terms of oxides by mass %, 73.1 to 90% of Bi2O3, 2 to 14.5% of B2O3, 0 to 25% of ZnO, 0.2 to 20% of MgO+CaO+SrO+BaO (total content of MgO, CaO, SrO, and BaO), and 0 to 8.5% of Si02+Al2O3 (total content of SiO2 and Al2O3).

Abstract: An optical glass comprising, by mass %, 12 to 40% of SiO2, 15% or more but less than 42% of Nb2O5, 2% or more but less than 18% of TiO2, (provided that Nb2O5/TiO2 is over 0.6), 0.1 to 20% of Li2O, 0.1 to 15% of Na2O, and 0.1 to 25% of K2O, and having an Abbe's number ?d of 20 to 30, a ?Pg,F of 0.016 or less and a liquidus temperature of 1,200° C. or lower.

Abstract: Embodiments are directed to glass frits containing phosphors that can be used in LED lighting devices and for methods associated therewith for making the phosphor containing glass frit and their use in glass articles, for example, LED devices.

Abstract: A glass for a light guide fiber GA1 is used in a core of a fiber 10 of a light guide, and has a refractive index nd between 1.56 and 1.74. The glass for a light guide fiber GA1 has the following composition: (A) SiO2: 20 to 55 wt %, (B11) B2O3: 0 to 2.0 wt %, (B2) does not contain P2O5 and GeO2, (C1) (BaO+SrO+La2O3+Lu2O3+Ta2O5+Gd2O3+WO3): 39 to 46 wt %, (D1) ZnO: 4 to 16 wt %, (E) does not contain Al2O3, (F) does not contain ZrO2, (G) does not contain PbO and As2O3, (H1) (Na2O+K2O): 4 to 10 wt %, (I) Sb2O3: 0 to 0.050 wt %, and (J1) (Na2SO4+K2SO4): 0.32 to 0.78 wt %.

Abstract: There is provided a glass composition having a devitrification temperature of 1000° C. or below, a glass transformation temperature (Tg) of 535° C. or below and a specific gravity within a range from 3 to 4. The glass composition has a refractive index (nd) within a range from 1.60 to 1.75 and an Abbe number (?d) within a range from 50 to 60.

Abstract: The present invention provides an optical glass, containing, in % by weight on an oxide basis, 30 to 50% of P2O5, 18 to 43% of BaO, 2 to 12% of B2O3, 1.4 to 5% of Al2O3, more than 0 to 6% of Li2O, more than 0 to 9% of La2O3, 0.1 to 8% of MgO, 0 to 10% of CaO, 0 to 15% of SrO, 0 to 5% of ZnO, 0 to 7% of Gd2O3, and 0 to 3% of SiO2, and having optical constants of a refractive index nd of 1.59 to 1.63 and an Abbe number ?d of 63 to 68.

Abstract: Provided is an optical glass having homogeneous optical characteristics such that striae and devitrification hardly occur at the time of producing a gob. The optical glass includes cationic components having the following composition, provided that a total of the cationic components is 95 cat %, and has a refractive index (nd) of 1.6 or more and less than 1.7 and an Abbe number (vd) of 50 or more and 56 or less, Si4+ 3 cat % or more and 13 cat % or less B3+ 40 cat % or more and 55 cat % or less La3+ 4 cat % or more and 9 cat % or less Ca2+ 6 cat % or more and 12 cat % or less Li+ 11 cat % or more and 18 cat % or less Zn2+ 6 cat % or more and 12 cat % or less Zr4+ 1 cat % or more and 4 cat % or less provided that Si4+/B3+ is 0.05 or more and 0.3 or less, and Li+/Zn2+ is 1.3 or more and 2.0 or less.

Abstract: A high-refractivity low-dispersion optical glass that can be stably supplied and has excellent glass stability and that has coloring reduced, composed of in mass %, 5 to 32% of total of SiO2 and B2O3, 45 to 65% of total of La2O3, Gd2O3 and Y2O3, 0.5 to 10% of ZnO, 1 to 20% of total of TiO2 and Nb2O5, and optionally other components. The optical glass has a refractive index nd of 1.89 to 2.0, an Abbe's number ?d of 32 to 38 and a coloring degree ?70 of 430 nm or less.

Abstract: The invention relates to aluminophosphate-based glasses suitable for use as a solid laser medium, which further contains SiO2 and B2O3. The laser glasses possess desirable figure of merit values for FOMTM and FOMlaser, as described herein.

Abstract: Disclosed is a glass material for press forming providing an optical element having a sufficient optical performance without surface cracks, cloudiness, scratches, and the like even when the glass material contains a highly reactive component. Also disclosed are an optical element having a sufficient optical performance without surface cracks, cloudiness, scratches, and the like and a method for manufacturing the same. Specifically disclosed is a glass material for press forming which comprises a core portion composed of multicomponent optical glass and a surface glass layer covering at least a region serving as an optical functional surface of the core portion. The surface glass layer contains more than 90 mass % of SiO2, and the thickness of the layer is less than five nanometers. Also specifically disclosed is a method for manufacturing a glass optical element by heating the glass material and by press forming the softened glass material using a forming die.

Abstract: An optical glass comprising, by mass %, 12 to 40% of SiO2, 15% or more but less than 42% of Nb2O5, 2% or more but less than 18% of TiO2, (provided that Nb2O5/TiO2 is over 0.6), 0.1 to 20% of Li2O, 0.1 to 15% of Na2O, and 0.1 to 25% of K2O, and having an Abbe's number ?d of 20 to 30, a ?Pg,F of 0.016 or less and a liquidus temperature of 1,200° C. or lower.

Abstract: Provided is a glass for electrode formation, comprising, as a glass composition in terms of mass %, 65.2 to 90% of Bi2O3, 0 to 5.4% of B2O3, and 0.1 to 34.5% of MgO+CaO+SrO+BaO+ZnO+CuO+Fe2O3+Nd2O3+CeO2+Sb2O3 (total content of MgO, CaO, SrO, BaO, ZnO, CuO, Fe2O3, Nd2O3, CeO2, and Sb2O3).

Abstract: A glass composition for protecting a semiconductor junction contains at least SiO2, Al2O3, MO, and nickel oxide, and substantially contains none of Pb, P, As, Sb, Li, Na and K (M in MO indicates one of alkali earth metals).

Abstract: An optical glass that is an oxide glass and comprises, by cationic %, 20 to 40% of a total of Si4+ and B3+, 15 to 40% of a total of Nb5+, Ti4+, W6+ and Zr4+, 0.2 to 20% of a total of Zn2+, Ba2+, Sr2+ and Ca2+, and 15 to 55% of a total of Li+, Na+ and K+, the cationic ratio of the content of B3+ to the total content of B3+ and Si4+ being 0.01-0.5, the cationic ratio of the content of Zr4+ to the total content of Nb5+, Ti4+, W6+ and Zr4+ being 0.05 or less, the molar ratio of the total content of Zn2+ and Ba2+ to the total content of Zn2+, Ba2+, Sr2+ and Ca2+ being 0.8-1, the optical glass having a refractive index nd of 1.815 or more and an Abbe's number ?d of 29 or less.

Abstract: An optical glass comprising, by mol %, 0.1 to 40% of SiO2, 10 to 50% of B2O3, 0 to 10% of total of Li2O, Na2O and K2O, 0 to 10% of total of MgO, CaO, SrO and BaO, 0.5 to 22% of ZnO, 5 to 50% of La2O3, 0.1 to 25% of Gd2O3, 0.1 to 20% of Y2O3, 0 to 20% of Yb2O3, 0 to 25% of ZrO2, 0 to 25% of TiO2, 0 to 20% of Nb2O5, 0 to 10% of Ta2O5, over 0.1% but not more than 20% of WO3, 0 to less than 3% of GeO2, 0 to 10% of Bi2O3, and 0 to 10% of Al2O3, the mass ratio of the content of SiO2 to the content of B2O3, SiO2/B2O3, being 1 or less, the optical glass having a refractive index nd of 1.86 to 1.95 and an Abbe's number ?d of (2.36?nd)/0.014 or more but less than 38.

Abstract: Disclosed is a lead-free, low melting point glass composition, which is characterized by being substantially free from a lead component and comprising 0-8 mass % of SiO2, 2-12 mass % of B2O3, 2-7 mass % of ZnO, 0.5-3 mass % of RO (MgO+CaO+SrO+BaO), 0.5-5 mass % of CuO, 80-90 mass % of Bi2O3, 0.1-3 mass % of Fe2O3, and 0.1-3 mass % of Al2O3. This glass composition is not easily crystallized at high temperatures and is stable. Therefore, it is useful as an insulating coating material and a sealing material for electronic material substrates.

Abstract: An optical glass that is an oxide glass having a very high refractive index in spite of its low-dispersion property, having excellent glass stability and having less susceptibility to coloring.

Abstract: Provided is a glass composition for protecting a semiconductor junction which contains at least SiO2, Al2O3, ZnO, CaO and 3 mol % to 10 mol % of B2O3, and substantially contains none of Pb, P, As, Sb, Li, Na and K. It is preferable that a content of SiO2 falls within a range of 32 mol % to 48 mol %, a content of Al2O3 falls within a range of 9 mol % to 13 mol %, a content of ZnO falls within a range of 18 mol % to 28 mol %, a content of CaO falls within a range of 15 mol % to 23 mol %, and a content of B2O3 falls within a range of 3 mol % to 10 mol %.

Abstract: The lead-free and arsenic-free optical glasses have a refractive index of 1.83?nd?1.95 and an Abbé number of 24??d?35, good chemical resistance, excellent crystallization stability and a composition, in wt. % based on oxide content, of SiO2, 2-8; B2O3, 15-22; La2O3, 35-42; ZnO, 10-18; TiO2, 9-15; ZrO2, 3-10; Nb2O5, 4-10; and WO3, >0.5-3. Besides containing at most 5 wt. % of each of GeO2, Ag2O and BaO and conventional fining agents, they may also contain at most in total 5 wt. % of Al2O3, MgO, CaO, SrO, P2O5 and up to at most in total 5 wt. % of the components F, Ta2O5. The glasses are preferably free of alkali metal oxides, Bi2O3, Y2O3, Gd2O3 and/or Yb2O3. Optical elements made from the optical glass are also described.

Abstract: An optical glass in includes SiO2, B2O3, Al2O3, BaO, CaO, ZnO, La2O3, Gd2O3, and Y2O3, each in a specific ratio. Further, the optical glass satisfies the following conditional expressions (1) and (2), taking the content of SiO2 as A, the content of B2O3 as B, the content in total of La2O3, Gd2O3 and Y2O3 as C, and the content in total of SiO2 and B2O3 as D. 0.35<A/B<0.70??(1) 0.80<C/D<1.0??(2) By the above constitution, a high refractive index and low dispersibility are secured and at the same time deformation temperature (and glass transition temperature) lowers. By containing Al2O3, the glass structure is stabilized and a failure in appearance such as cloudiness in press molding is difficult to occur.

Abstract: A flat panel display glass substrate includes a glass comprising, in mol %, 55-80% SiO2, 3-20% Al2O3, 3-15% B2O3, and 3-25% RO (the total amount of MgO, CaO, SrO, and BaO). The contents in mol % of SiO2, Al2O3, and B2O3 satisfy a relationship (SiO2+Al2O3)/(B2O3)=7.5-17. The strain point of the glass is 665° C. or more. The devitrification temperature of the glass is 1250° C. or less. The substrate has a heat shrinkage rate of 75 ppm or less. The rate of heat shrinkage is calculated from the amount of shrinkage of the substrate measured after a heat treatment which is performed at a rising and falling temperature rate of 10° C./min and at 550° C. for 2 hours by the rate of heat shrinkage (ppm)={the amount of shrinkage of the substrate after the heat treatment/the length of the substrate before the heat treatment}×106.

Abstract: The present invention relates to an optical glass containing, in terms of mass % on the basis of oxides, B2O3: 10 to 20%, SiO2: 0.5 to 12%, ZnO: 5 to 19%, Ta2O5: 2.5 to 17%, Li2O: 0.2 to 3%, ZrO2: 0.6 to 4.9%, WO3: 1 to 20%, La2O3: 25 to 50%, Gd2O3: 0 to 13%, and Y2O3: 0.2 to 20%, provided that La2O3+Gd2O3+Y2O3 is 35 to 60%, in which the optical glass does not substantially contain Nb2O5, and has a refractive index (nd) of 1.82 to 1.86, an Abbe's number (?d) of 37 to 44 and a glass transition point (Tg) of 630° C. or lower.

Abstract: An optical glass in which a Cr content is less than 5 ppm, or a Sm content is 3 ppm or less, with respect to a 100% basic glass composition containing 2-10% SiO2, 5-45% B2O3, 0-15% RO (R?Zn, Sr, Ca, Ba), 30-60% La2O3, 0-40% Ln2O3 (Ln=Y, Gd), and, 0-30% ZrO2+Nb2O5+Ta2O5 by weight, and an optical apparatus which is provided with an optical system having the optical glass.

Abstract: The invention provides an environment-friendly optical glass with high refractive index, low dispersion and high light transmittance. The optical glass includes 6%-17% of B2O3, 2-10% of SiO2, more than 25% but less than 45% of La2O3, 5-25% of Gd2O3, 0-3% of Nb2O5, more than 19% but less than 27% of Ta2O5, 0-16% of ZnO, 0-5% of BaO, 0-5% of CaO, 0-5% of SrO, 0-9% of ZrO2, 0-8% of Y2O3, 0-8% of Yb2O3, 0-5% of WO3, 0-2% of Li2O, Na2O and K2O, equal to 0.01% but less than 0.1% of Sb2O3 and 0-1% of SnO2 optical glass. The environment-friendly optical glass does not contain GeO2, and has refractive index of 1.85-1.90, Abbe number of 35-45, the corresponding wavelength below 440 nm when transmittance thereof reaches 80% and high transmittance.

Abstract: An object of the invention is to provide an optical glass for precision press having optical properties of a high refractive index and a low dispersion property and having a low molding temperature, a high devitrification resistance, an excellent molding property, and a small specific gravity. The optical glass of the invention contains, in terms of % by mass on the basis of oxides, respective components of B2O3: 10 to 20%, SiO2: 0.5 to 12%, La2O3: 25 to 50%, Gd2O3: 0 to 20%, Y2O3: 0 to 20%, provided that La2O3+Gd2O3+Y2O3: 35 to 60%, ZnO: 5 to 20%, Li2O: 0.2 to 3%, ZrO2: 0 to 0.5%, Ta2O5: 3 to 18% and WO3: 3 to 20%, and has optical constants of a refractive index nd of 1.84 to 1.86 and an Abbe number vd of 37 to 42 and a glass transition point (Tg) of 630° C. or lower.

Abstract: A flat panel display glass substrate according to the present invention includes a glass comprising, as expressed in mol %, 55-80% SiO2, 3-20% Al2O3, 3-15% B2O3, 3-25% RO (the total amount of MgO, CaO, SrO, and BaO), and substantially no As2O3 and Sb2O3. The devitrification temperature of the glass is 1250° C. or less. The glass substrate has a heat shrinkage rate of 75 ppm or less. The heat shrinkage rate is calculated from the amount of shrinkage of the glass substrate measured after a heat treatment which is performed at a temperature rising and falling rate of 10° C./min and at 550° C. for 2 hours by the heat shrinkage rate (ppm)={the amount of shrinkage of the glass substrate after the heat treatment/the length of the glass substrate before the heat treatment}×106.

Abstract: A lens formed of a high-refractivity low-dispersion glass and free of fogging and scorching on its optical-function surface, which is obtained by precision press-molding of an optical glass having a refractive index (nd) of over 1.83, an Abbe's number (?d) of 40 or more and a glass transition temperature (Tg) of 640° C. or lower and containing no Li2O and has one form of a meniscus form, a biconcave form or a plano-concave form.