摘要:
A process and apparatus are described for rapidly drying a wet, porous gel monolith of glass or ceramic, at subcritical temperatures without inducing any cracking of the gel. The wet gel is immersed in a liquid solvent in a chamber, and the liquid solvent is then heated and expelled from the chamber. Further heating, with or without the presence of a flowing inert gas, fully dries the wet gel. When an inert gas is used, the gas is delivered to the chamber with a controlled solvent partial vapor pressure, to correspondingly control the driving force for drying the gel.
摘要:
A process and apparatus are described for rapidly drying a wet, porous gel monolith of glass or ceramic, at subcritical temperatures without inducing any cracking of the gel. The wet gel in immersed in a liquid solvent in a chamber, and the liquid solvent is then heated and expelled from the chamber. Further heating, with or without the presence of a flowing inert gas, fully dries the wet gel. When an inert gas is used, the gas is delivered to the chamber with a controlled solvent partial vapor pressure, to correspondingly control the driving force for drying the gel.
摘要:
An improved sol-gel process for fabricating large, crack-free gel monoliths (e.g., of silica) is described in which a specially-tailored gel microstructure is provided by adjusting the relative concentrations of an alcohol diluent (e.g., ethanol) and/or one or more catalysts (e.g., HCl and HF). Controlled variations in the gel's average pore radius, bulk density, rupture modulus, and elastic modulus over a wide range can be tailored in this fashion. This enables the process to be optimized for the particular application involved.
摘要:
A sol-gel process is disclosed for depositing multi-layer antireflection coatings on plastic substrates. One or more polymerized, titanium-containing solutions are provided by mixing a titanium alkoxide, an alcohol, and water, and one or more polymerized, silicon-containing solutions are provided by mixing a silicon alkoxide, an alcohol, and water. These solutions are applied to the plastic substrate in an alternating fashion, to produce a succession of uniform layers of polymerized titanium dioxide and polymerized silicon dioxide. Each layer is individually cured before the next layer is applied. The resulting coating of multiple polymerized layers provides very low reflectance over the entire visible wavelength range, yet with excellent mechanical strength and durability.
摘要:
A glass optical waveguide filament preform is prepared by chemical reaction of vapor ingredients within a glass bait tube. A reactant feed tube extends into one end of the bait tube and terminates just short of the hot zone where reaction occurs. The end of the feed tube traverses the bait tube along with the burner which generates the hot zone. Reactants flow radially from slots in the end of the wall of the feed tube and combine with a flushing gas to form a mixture which flows in a spiral path through the hot zone.
摘要:
An outside chemical vapor deposition apparatus is disclosed for depositing porous glass-forming material onto a target rod to form a cylindrical body, with substantially higher efficiency than could prior apparatus. The apparatus includes two separate burner arrays, one array optimized for depositing the material during an initial stage of the process, when the cylindrical body has a relatively small diameter, and the other array optimized for depositing the material during a later stage of the process, when the cylindrical body has a relatively large diameter. In addition, each burner array can include a plurality of burners, with each burner azimuthally angled relative to the apparatus' air-flow axis, and with adjacent burners angled in opposite directions relative to that axis, to minimize the density gradient within the deposited porous material.
摘要:
Low attenuation, low dispersion of optical waveguides are provided by a process initiating with axial deposition of a high velocity core soot stream impinging on a target at a high angle of incidence relative to the axis of rotation of the target. A core cylinder is built up axially by relative movement between the soot stream and target during deposition, the movement being non-constant in order to maintain a substantially constant diameter with a constant deposition rate. A cladding layer is then built up by deposition of soot radially on the core. Subsequent drying and sintering provides a vitreous preform which may be drawn directly into optical waveguides. Alternatively, the sintered product may be drawn down to smaller rods, which then are covered with further deposited soot cladding to a desired final thickness, and after further drying and sintering may be drawn to optical waveguides.
摘要:
A method of forming a preform or blank for a high bandwidth gradient index optical filament, the preform itself and the resulting optical filament is disclosed. The preform which ultimately forms the optical filament includes a barrier layer between a tubular starting member which comprises the cladding and the core, the index of refraction of the barrier layer being equal to or less than the index of refraction of the tubular starting member; there being no step increase in the index of refraction of the barrier layer at the barrier layer-cladding interface nor of the core at the core-barrier layer interface of the optical filament. The tubular starting member is formed of a base glass and at least one dopant, the index of refraction of the tubular starting member being in excess of said base glass. The barrier layer is formed from a base glass and at least one dopant which is maintained substantially constant in the barrier layer. The core is formed of a base glass and at least one dopant which is gradually varied during the formation of the core, the core being free of B.sub.2 O.sub.3.
摘要:
The present disclosure relates to the field of microelectronic die packaging, particularly multi-chip packaging, wherein on-substrate modularity is enabled by using in-street die-to-die interconnects to facilitate signal routing between microelectronic dice. These in-street die-to-die interconnects may allow for manufacturing of several products on a single microelectronic substrate, which may lead to improved microelectronic die and/or microelectronic module harvesting and increased product yields.
摘要:
An outside chemical vapor deposition apparatus is disclosed for depositing porous glass-forming material onto a target rod to form a cylindrical body, with substantially higher efficiency than could prior apparatus. The apparatus includes two separate burner arrays, one array optimized for depositing the material during an initial stage of the process, when the cylindrical body has a relatively small diameter, and the other array optimized for depositing the material during a later stage of the process, when the cylindrical body has a relatively large diameter. In addition, each burner array can include a plurality of burners, with each burner azimuthally angled relative to the apparatus' air-flow axis, and with adjacent burners angled in opposite directions relative to that axis, to minimize the density gradient within the deposited porous material.