Abstract:
Helium recycling for optical fiber manufacturing in which consolidation process helium is recycled (440) either directly for use in consolidation at high purity or recycled at lower purity adequate for usage in draw or other processes having a lower helium purity. Integrated processes for recycling helium from two or more helium using processes in the optical manufacturing process are also described. Substantial helium and cost savings are recognized.
Abstract:
The device includes a housing (1), a means for heating the housing (2), and a means (8) for supporting, in the housing, at least one group (9i) composed of plates (24i) of malleable material under pressure at the temperature established in the housing (1). Moreover, the group (9i) includes generally flat molds (25i, 25'1, 25'2) and each mold includes at least one non malleable pitted surface under pressure at said temperature. The molds (25i, 25'1, 25'2) are inserted between the plates (24i). Means (13, 15, 19, 20, 21) are envisaged to apply a roughly uniform pressure, oriented perpendicularly to the surface of the plates (24i) to the entire group (9i). This pressure is suitable for causing the production of convex surfaces of microlenses on the sides of the plates (24i), which are opposite said pitted surfaces of the molds (25i, 25'1, 25'2).
Abstract:
The present invention is directed to a silica forming feedstock and a method of making optical wageguides and optical waveguide preforms. The feedstock for use in the manufacturing of germanium doped silica glass products includes a siloxane and a germanium dopant component such as germanium alkoxide. The invention further relates to the manufacturing of optical waveguides and optical waveguide preforms using a fluid feedstock which includes a siloxane and germanium dopant component preferably germanium alkoxide.
Abstract:
A package for a temperature sensitive optical component (20) includes inner (14) and outer (12) containers of low thermal conductivity plastics material, a foam insulation (18) being situated between the two containers. Within the inner container (14) are a thermally conductive plate to which the component (20), a temperature sensitive resistor, and a resistive heating element are affixed. A temperature compensating circuit (16) is located outside the inner container. The temperature sensitive resistor is part of a Wheatstone bridge at the input of the circuit (16), whereby the circuit compensates for variations in operating voltage. The output transistor of the circuit regulates the current through the resistive heating element in response to variations in the resistance of the temperature sensitive resistor. This transistor extends into the inner container (14) and is in contact with the thermally conductive plate, whereby heat from the transistor is dissipated into the plate. This maintains the temperature of the transistor substantially constant.
Abstract:
A polarizing glass article, and a method of making the article, that exhibits a broad band of high contrast polarizing properties in the infrared region of the radiation spectrum, that is phase-separated by precipitating silver, copper, or copper-cadmium halide crystals in the glass within a size range of 200-5000 ANGSTROM , and that contains elongated silver, copper, or copper-cadmium metal particles formed on or in the halide crystals, and having an elongated aspect ratio of at least 2:1, the article having a contrast ratio of at least 100,000 over a range of at least 300 nm.
Abstract:
According to this method, a sheet made of a material in the plastic state is processed by thermoforming. A mold (4) is made, which is perforated with the pluralities of holes (5i) distributed according to a distribution of wells to be formed in said sheet, said sheet is placed on said mold (4) and the sheet is heated to a temperature where it is in the plastic state, and c) between the two sides of the sheet, a gas pressure difference is established so that the material of said sheet, perpendicular to the holes of the mold, is aspired into these holes to assume the shape of wells (7i) whose bottoms are separated from any contact with other surfaces.
Abstract:
Fused silica stepper lens for photolithographic application are disclosed which are resistant to laser-induced damage, specifically, compaction or densification which can lead to an increase in the optical path length of the lens. The figure compares the phase front distortions of a standard fused silica with the phase front distortions observed in two inventive stepper lens fused silica.
Abstract:
A multiplexer/demultiplexer (10) for routing different wavelength signals between a common pathway (12) for conveying a plurality of the signals, and individual pathways (14a-14b) for separately conveying the signals, includes a reflective diffraction grating (16) with reduced polarization sensitivity for dispersing the signals. The grating (16) includes facets (20) that are oriented for reducing efficiency variations within a transmission bandwidth and that are shaped for reducing differences between the diffraction efficiencies in two orthogonal directions of polarization.
Abstract:
Improved optical waveguide fiber (1) comprised of a central core (10) region surrounded by inner clad region (12). The second annular region (14) is doped with tantalum. The core (10) is doped with germanium. The first annular region (20) located between two adjacent regions of relatively high indexes of refraction. The index of refraction of both adjoining regions (10, 20) is greater than the central region (20).
Abstract:
A fusion sealing material, and a fusion seal prepared therefrom, consisting essentially of at least 65 % of a SnO-ZnO-P2O5 glass frit, up to 10 % of a crystallization catalyst and 0-25 % of an additive that decreases the effective CTE of a seal prepared with the material.