Abstract: An optical device assembled by means of an adhesive composition which is free from the cracking of an adhesive layer thereof, is prepared easily and has excellent adhesive strength. The optical device is produced by placing an adhesive composition prepared by hydrolyzing, dehydrating and condensing a starting solution which contains 10 to 50 mol % of a silane compound represented by SiX14 (X1 is a hydrolyzable group) or a combination of the silane compound and a metal alkoxide, 25 to 65 mol % of a silane compound represented by PhSiX23 (Ph is a phenyl group or substituted phenyl group, and X2 is a hydrolyzable group), and 25 to 65 mol % of a silane compound represented by (CH3)2SiX32 (X3 is a hydrolyzable group) between an optical part and another part and heating it to bond the optical part to the another part.

Abstract: An article having a predetermined surface configuration, such as an optical element having fine irregularities in the surface which has high heat resistance, small heat shrinkage at the time of molding a film and high dimensional stability, and a production process therefor. The article having a predetermined surface configuration is produced by setting a composition comprising a compound which contains a dimethylsiloxane skeleton having at least three recurring units and at least one polymerizable organic group in the molecule between and in contact with the surface of a substrate and the molding surface of a mold in the form of a film, applying at least one of heat and ultraviolet radiation to the composition, removing the mold, and heating as required to form a film having a surface configuration which is the inversion of the surface configuration of the mold on the surface of the substrate.

Abstract: There can be provided a method for producing a pattern film-coated article which has excellent film formability, can remove unexposed portions of a film completely in the development step after exposing the film to light. and has excellent pattern accuracy; and a photosensitive composition. The method for producing a pattern film-coated article comprises the steps of coating a photosensitive composition comprising an organometallic or organosilicon compound having photosensitivity and a hydrolyzable metal or silicon alkoxide on a substrate, irradiating the coated film on the substrate with light to polymerize the exposed portions of the coated film and then dissolving unexposed portions to remove them, wherein a pattern film-coated article is produced from an allyl group-containing metal or silicon alkoxide as the organometallic or organosilicon compound.

Abstract: An echelon diffraction grating which has excellent heat resistance and can be produced at a low cost and an optical waveguide which has high heat resistance, small absorption of a communication wavelength of a near infrared range, and satisfies reliability and a low loss at an optical communication range. The echelon diffraction grating comprises a substrate, and an organopolysiloxane film having a maximum thickness of 1 &mgr;m to 1 mm formed on the surface of the substrate and has a plurality of steps having a predetermined width of 1 to 500 &mgr;m and a predetermined height of 5 to 500 &mgr;m formed on the organopolysiloxane film, and the organopolysiloxane film contains dimethylsiloxane and phenyl(or substituted phenyl)siloxane as essential ingredients.

Abstract: An optical device assembled by means of an adhesive composition which is free from the cracking of an adhesive layer thereof, is prepared easily and has excellent adhesive strength.

Abstract: Anti-reflection colored film-coated glass products prepared by forming on a transparent glass substrate with a refractive index of 1.47-1.53, a high refractive index film with a refractive index of 1.59-2.30 and a film thickness of 80-140 nm and containing 0-85% silicon oxides, 10-95% titanium oxides and 5-30% fine gold particles in terms of weight percentage, and by forming on the high refractive index film, a low refractive index film with a refractive index which is a value in the range of 1.35-1.58 and at least 0.20 smaller than the refractive index of the high refractive index film, having a film thickness of 70-99 nm and containing 90-100% silicon oxides in terms of weight percentage.

Abstract: To provide a light transmitting material which has high transmission at wavelength ranges used for communication and excellent characteristic properties such as heat resistance, water resistance and chemical resistance, and makes it possible to produce a grating and incorporate it in a mounting module with ease. A photosensitive composition for forming a light transmitting material comprising a silane compound or hydrolysis/dehydration condensation reaction product thereof, a photoinitiator and water, the silane compound being represented by the following formula (1): R1SiX13  (1) wherein R1 is an organic group having a polymerizable carbon-carbon double bond, and X1 is a hydrolyzable group or atom, with the proviso that at least 40% of the total number of hydrogen atoms of the organic group R1 are substituted by at least one substituent atom selected from the group consisting of deuterium, fluorine, chlorine and bromine.

Abstract: An optical circuit is designed with demultiplexing and optical detection functionality with minimal crosstalk. An Nth order harmonic generation device is positioned before the demultiplexer to either convert the frequency or down convert the wavelength of the demultiplexed light wave by N-times. Upconverting the multiplexed signal at the receiver station is performed by either simultaneously upconverting N-times to create N times the original spacing between each optical channel or by upconverting the frequency of one optical channel at a time.

Abstract: An article having a predetermined surface configuration comprising a substrate and a gelled film having a high refractive index, excellent heat resistance, high film hardness and excellent transferability formed on the surface of the substrate.

Abstract: An optical element comprises a solid material in an optical path of the optical element, wherein the solid material comprises a first material and a second material, and the first and second materials have first and second temperature coefficients of refractive index, respectively, wherein the first temperature coefficient of refractive index has a sign which is opposite that of the second temperature coefficient of refractive index.

Abstract: A process for producing an optical element which has excellent heat resistance and adhesion to a substrate. This process comprises applying a liquid composition for forming an optical element to the molding surface of a substrate having a regular pattern surface consisting of areas having high wettability and areas having low wettability as the molding surface and curing the composition to form projections in the areas having high wettability. A solution containing at least one compound selected from the group consisting of a hydrolyzable compound which can be hydrolyzed and polycondensed and a hydrolyzed/polycondensed product thereof is used as the liquid composition for forming an optical element.

Abstract: A method of bonding an optical part, comprising the steps of applying a primer composition which comprises a trialkoxysilane having an epoxy group or alkenyl group, tetraalkoxysilane, Ti, Al or Zr alkoxide and a solvent to the surface of an optical part to be bonded, placing an epoxy resin or silicon resin adhesive composition between the optical part and another optical part and curing it.

Abstract: A process for producing an article having a fine uneven surface, coated with a film which has high heat resistance, does not crack and does not peel off from a substrate. The process for producing the article comprises disposing a film-forming solution between a substrate and a mold in the form of a film so as to make the solution closely contact with the substrate and the mold, said solution being prepared by carrying out the hydrolysis and dehydration polycondensation reaction of a stock solution containing a specific silane compound (A) having an unhydrolyzable organic group and a hydrolyzable group, a specific silane compound (B) having a hydrolyzable group and a catalyst, and heating to form an article having an uneven film having a surface shape which is the inversion of the surface shape of the mold on the surface of the substrate. The film-forming solution contains the above silane compounds (A) and (B) in the form of unhydrolysates in amounts of 0.5 to 40 wt % and 0.

Abstract: There is provided an article which can be produced at a low cost, is excellent in heat resistance, chemical resistance and dimensional accuracy, and has a predetermined surface shape. In particular there is provided an optical waveguide which has high heat resistance and chemical resistance, a large difference in refractive index, small absorption at a communication wavelength of a near infrared range, reliability and a low loss at an optical communication range. The process for producing the article involves disposing a sol-gel material containing specified silanes between a substrate and a mold in the form of a film so as to make the sol-gel material closely contact the substrate and the mold, and heating to form a gelled film having a surface shape which is the inversion of the surface shape of the mold on the surface of the substrate.

Abstract: A process for producing a coated article which has excellent releasability and a surface pattern having a high degree of accuracy efficiently. The process is a process for producing an article having a given surface pattern, which comprises holding a mold horizontally with its surface facing up, feeding a sol-gel material solution onto the surface to form a film, heating them, bringing a substrate into contact with the film, heating them, removing the mold, and further heating the film and the substrate as required to obtain the article having a gelled film whose surface pattern is the inverse of a surface pattern of the mold coated on a surface of the substrate, wherein sol-gel material solution film edge holding zone is provided along the perimeter of the surface of the mold at a lower position than the surface of the mold, and the sol-gel material solution is fed such that the edges of the formed film of the sol-gel material solution reach the zone beyond the perimeter of the surface of the mold.

Abstract: An optical device having at least two optically transparent optical parts which are bonded together with an optically transparent adhesive layer. The adhesive layer is formed from a matrix containing silicon, titanium, zirconium, aluminum or germanium, and oxygen atoms. At least part of the atoms is bonded to other atom(s) through a polyvalent hydrocarbon group and directly bonded a monovalent hydrocarbon group. The refractive index value of the adhesive layer approximates to the refractive index values of the at least two optically transparent optical parts. An adhesive composition for bonding optical parts and a method of bonding optical parts are also proposed.

Abstract: A process for producing articles covered with a patterned film which can be formed by a short time of exposure and has high development sensitivity after exposure and excellent pattern accuracy and a photosensitive composition. The process comprises applying the photosensitive composition to a substrate, exposing the coating film to light in a pattern-form to polymerize exposed portions of the coating film, dissolving and removing unexposed portions. The composition comprises a metal alkoxide, a &bgr;-diketone and acrylic acid or methacrylic acid.

Abstract: An article having a predetermined surface configuration, such as an optical element having fine irregularities in the surface which has high heat resistance, small heat shrinkage at the time of molding a film and high dimensional stability, and a production process therefor. The article having a predetermined surface configuration is produced by setting a composition comprising a compound which contains a dimethylsiloxane skeleton having at least three recurring units and at least one polymerizable organic group in the molecule between and in contact with the surface of a substrate and the molding surface of a mold in the form of a film, applying at least one of heat and ultraviolet radiation to the composition, removing the mold, and heating as required to form a film having a surface configuration which is the inversion of the surface configuration of the mold on the surface of the substrate.

Abstract: An adhesive composition for bonding optical parts comprising (A) 3 to 60 wt % of an epoxysilane or a hydrolysis/polycondensation product thereof, (B) 5 to 90 wt % of a bisphenol type epoxy resin having a viscosity of 2,000 to 5,000 mPa·s, (C) 5 to 35 wt % of a novolak type epoxy resin, 3 to 30 wt % of a curing agent which is an amine, and water and an alcohol in an amount of 0 to 0.75 time the total number of mols of the hydrolyzable groups or atoms of the epoxysilane. This composition has excellent moisture resistance and heat resistance, suppresses the formation of bubbles during curing, is free from such a defect as opaqueness caused by bubbles and can be used for the assembly and bonding of optical parts.

Abstract: There can be provided a method for producing a pattern film-coated article which has excellent film formability, can remove unexposed portions of a film completely in the development step after exposing the film to light. and has excellent pattern accuracy; and a photosensitive composition.