Abstract:
Coating compositions, and methods for depositing them on the surface of an article to produce an antireflection coating, are disclosed. In one embodiment, the coating composition includes a (meth)acrylate-functional silicon alkoxide, silica particles, a (meth)acrylate monomer, an epoxy (meth)acrylate oligomer, a photoinitiator, a solvent, an acid, and water. The relative amounts of these constituents are controlled such that, when the coating composition is deposited onto the surface of an article and cured, it has a refractive index less than about 1.60 at a wavelength of 510 nm. In another embodiment, the coating composition includes an organo-metallic compound other than an organo-metallic compound of silicon, an epoxy-functional silicon alkoxide, a non-epoxy-functional silicon alkoxide, a curing agent compatible with epoxy-functional molecules, a solvent, an inorganic acid, and water. The relative amounts of these constituents are controlled such that, when the coating composition is deposited onto the surface of an article and cured, it has a refractive index greater than about 1.70 at a wavelength of 510 nm. The coating compositions are deposited in a process that produces an antireflection coating in less than 90 minutes of processing time.
Abstract:
An encapsulant is described for an optoelectronic device or optical component, which provides a coefficient of thermal expansion of less than 50 ppm/° C., with a variation of less than ±30%, and further provides an optical transmittance of at least 20% at a wavelength in the range of 400 to 900 nm, at an encapsulant thickness of about 1 mm. The encapsulant includes a filler consisting essentially of glass particles having diameters smaller than 500 μm, being essentially free of titania and lead oxide, and having a refractive index in the range of 1.48 to 1.60, with a variance of less than about 0.001. A method for making the encapsulant also is described, the method including steps of (1) processing the glass to form particles having diameters between 1 and 500 μm, (2) preparing an epoxy resin composition having at a cured stage a refractive index close to that of the glass filler particles, (3) mixing the epoxy resin composition with the filler particles to form a filled epoxy resin composition, (4) encapsulating an optoelectronic device with the filled epoxy resin composition, and (5) curing the filled epoxy resin composition.
Abstract:
An optical fiber which has just been drawn from an optical preform is provided with two external hermetic coatings. The primary coating is a metallic or dielectric coating provided by, for example, using a heterogeneous nucleation thermochemical deposition (HNTD) technique. This technique involves passing the fiber through a reaction zone which contains a gaseous medium that includes a reactant which decomposes, or a mixture of reactants which chemically react, at a predetermined temperature, to form the material of the coating. Such predetermined temperature is available from the heat of the fiber forming process which is retained at the fiber surface by means of a shielding element so that additional heating means is not required. The second coating may be deposited, by for example, using an HNTD or a chemical vapor deposition process. The resulting fiber may then be provided with an additional polymer coating layer.
Abstract:
Coating compositions, and methods for depositing them on the surface of an article to produce an antireflection coating, are disclosed. In one embodiment, the coating composition includes a (meth)acrylate-functional silicon alkoxide, silica particles, a (meth)acrylate monomer, an epoxy (meth)acrylate oligomer, a photoinitiator, a solvent, an acid, and water. The relative amounts of these constituents are controlled such that, when the coating composition is deposited onto the surface of an article and cured, it has a refractive index less than about 1.60 at a wavelength of 510 nm. In another embodiment, the coating composition includes an organo-metallic compound other than an organo-metallic compound of silicon, an epoxy-functional silicon alkoxide, a non-epoxy-functional silicon alkoxide, a curing agent compatible with epoxy-functional molecules, a solvent, an inorganic acid, and water. The relative amounts of these constituents are controlled such that, when the coating composition is deposited onto the surface of an article and cured, it has a refractive index greater than about 1.70 at a wavelength of 510 nm. The coating compositions are deposited in a process that produces an antireflection coating in less than 90 minutes of processing time.
Abstract:
Coating compositions, and methods for depositing them on the surface of an article to produce an antireflection coating, are disclosed. In one embodiment, the coating composition includes a (meth)acrylate-functional silicon alkoxide, silica particles, a (meth)acrylate monomer, an epoxy(meth)acrylate oligomer, a photoinitiator, a solvent, an acid, and water. The relative amounts of these constituents are controlled such that, when the coating composition is deposited onto the surface of an article and cured, it has a refractive index less than about 1.60 at a wavelength of 510 nm. In another embodiment, the coating composition includes an organo-metallic compound other than an organo-metallic compound of silicon, an epoxy-functional silicon alkoxide, a non-epoxy-functional silicon alkoxide, a curing agent compatible with epoxy-functional molecules, a solvent, an inorganic acid, and water. The relative amounts of these constituents are controlled such that, when the coating composition is deposited onto the surface of an article and cured, it has a refractive index greater than about 1.70 at a wavelength of 510 nm. The coating compositions are deposited in a process that produces an antireflection coating in less than 90 minutes of processing time.
Abstract:
An encapsulant is described for an optoelectronic device or optical component, which provides a coefficient of thermal expansion of less than 50 ppm/° C., with a variation of less than ±30%, and further provides an optical transmittance of at least 20% at a wavelength in the range of 400 to 900 nm, at an encapsulant thickness of about 1 mm. The encapsulant includes a filler consisting essentially of glass particles having diameters smaller than 500 μm, being essentially free of titania and lead oxide, and having a refractive index in the range of 1.48 to 1.60, with a variance of less than about 0.001. A method for making the encapsulant also is described, the method including steps of (1) processing the glass to form particles having diameters between 1 and 500 μm, (2) preparing an epoxy resin composition having at a cured stage a refractive index close to that of the glass filler particles, (3) mixing the epoxy resin composition with the filler particles to form a filled epoxy resin composition, (4) encapsulating an optoelectronic device with the filled epoxy resin composition, and (5) curing the filled epoxy resin composition.
Abstract:
An encapsulant for use with opto-electronic devices and optical components incorporates a filler made from a glass that has been processed into particle form and heated to a predetermined temperature for a predetermined time, along with an epoxy having an index of refraction matched to that of the glass and heated to a predetermined temperature for a predetermined time, to prevent settling of the filler particles after mixing the filler particles with the epoxy, and thereby obtaining uniform dispersion of the particles within the epoxy. The encapsulant provides for high light transmittance, and its coefficient of thermal expansion can be varied by varying the amount of filler without substantially altering the optical properties of the encapsulant. The coefficient of thermal expansion variation within the encapsulant preferably is less than 30%, due to uniform dispersion of the filler particles within the epoxy.
Abstract:
A method for hermetically sealing a silica based fiber product after the fiber product has been drawn from a melt or preform wherein a hermetic layer of boron carbide or a ceramic compound having a density of above about 4 g/cc is deposited upon the fiber product. The fiber product can be initially coated with carbon or boron carbide prior to the application of the ceramic compound. Also, a method for making such fiber products using these methods, and the resultant hermetically sealed fiber products produced thereby.
Abstract:
An article comprising a substrate and an anti-reflection coating, and methods for depositing the coating, are disclosed. The coating comprises (a) a first coating layer having a high refractive index deposited on the substrate; (b) an epoxide-silica coating layer deposited onto the high refractive index coating layer, comprising an inorganic silica component and an organic organo-silicate component, and (c) a silica coating layer consisting essentially of silica, deposited directly onto the epoxide-silica coating layer. The anti-reflection coating optionally comprises a stack of coating layers, between the first high refractive index coating layer and the epoxide-silica coating layer, having alternating a low refractive index and a high refractive index. Individual coating layer compositions, refractive indexes, and thicknesses are carefully controlled such that reflectance is minimized through destructive interference in the visible light wavelength range of 400 to 700 nm. The resulting deposited coating provides excellent mechanical, chemical, and environmental durability.
Abstract:
An encapsulant for use with opto-electronic devices and optical components incorporates a filler made from a glass that has been processed into particle form and heated to a predetermined temperature for a predetermined time, along with an epoxy having an index of refraction matched to that of the glass and heated to a predetermined temperature for a predetermined time, to prevent settling of the filler particles after mixing the filler particles with the epoxy, and thereby obtaining uniform dispersion of the particles within the epoxy. The encapsulant provides for high light transmittance, and its coefficient of thermal expansion can be varied by varying the amount of filler without substantially altering the optical properties of the encapsulant. The coefficient of thermal expansion variation within the encapsulant preferably is less than 30%, due to uniform dispersion of the filler particles within the epoxy.