Abstract: A known method for producing a cylindrical body uses a precipitation assembly (5) consisting of several precipitators (4), to which a parent substance is fed via medium supply lines (9), whereby the precipitation assembly (5) completes a closed trajectory (6) according to a predetermined displacement course, said trajectory comprising at least one precipitation path (8) that runs along the longitudinal axis (2) of the support. The aim of the invention is to provide an economical, reproducible, failsafe method based on said known procedure, which enables in particular the production of soot layers (3) on a support (1) at a high precipitation rate and nevertheless a high degree of uniformity. To achieve this, the displacement course (6) comprises a first loop (7a, 8) and a second loop (7b, 8), whereby the completion of the first loop (7a, 8) causes a right-hand torsion in the medium supply lines (9) and the completion of the second loop (7b, 8) causes a left-hand torsion in said lines (9).

Abstract: The present invention provides an optical synthetic quartz glass material which substantially does not cause changes in transmitted wave surface (TWS) by solarization, compaction (TWS delayed), rarefaction (TWS progressed) and photorefractive effect when ArF excimer laser irradiation is applied at a low energy density, e.g. at energy density per pulse of 0.3 mJ/cm2 or less. The present invention further provides a method for manufacturing the same. In order to solve the above-mentioned problems, the optical synthetic quartz glass material of the present invention is characterized in that, in a synthetic quartz glass prepared by a flame hydrolysis method using a silicon compound as a material, the followings are satisfied that the amount of SiOH is within a range of more than 10 ppm by weight to 400 ppm by weight, content of fluorine is 30 to 1000 ppm by weight, content of hydrogen is 0.

Abstract: A quartz glass crucible for use in pulling up a silicon single crystal, wherein it has, at least in the curved portion thereof, a three-layer structure comprising a transparent inner layer being composed of a synthetic quartz glass and having a low Al concentration, a transparent or nontransparent intermediate layer being composed of a natural quartz glass or a mixture of natural and synthetic quartz glasses and having a high Al concentration, and a nontransparent outer layer being composed of a natural quartz glass and having an Al concentration higher than that of the intermediate layer. The quartz glass crucible is reduced in the deformation of the transparent inner layer, and allows the suppression of the change in the amount of dissolution of the quartz glass crucible associated with the pull-up of a single crystal and the achievement of the uniform oxygen concentration in the longitudinal direction of a single crystal.

Abstract: It is an object of the present invention to provide synthetic quartz glass optical materials suitable for use in YAG of higher order harmonics. The damage threshold value in J/cm2 (energy density at which cracks occur generated by irradiation) is to be considered when synthetic quartz glass material is irradiated with YAG laser of third or higher order harmonics with single pulses or continuously. Regarding a synthetic quartz glass optical material in use for the optical parts constituting the prism and lens used in a laser beam machine, this invention provides a synthetic quartz glass material suitably used for the YAG laser with the third or higher order of harmonic, choosing the following conditions: OH group concentration is in the range of ?1 to ?300 ppm; contained hydrogen molecule concentration is in the range of ?2×1018 to ?2×1019 molecules/cm3; transmittance of ultraviolet rays at 245 nm of wavelength is 99.9% or more; and the fictive temperature is in the range of ?880 to ?990° C.

Abstract: Method and apparatus for dynamically placing sensors in a 3D model is provided. Specifically, in one embodiment, the method selects a 3D model and a sensor for placement into the 3D model. The method renders the sensor and the 3D model in accordance with sensor parameters associated with the sensor and parameters desired by a user. In addition, the method determines whether an occlusion to the sensor is present.

Abstract: An object of the present invention is to provide a polishing method for producing, in a relatively short period of time, a tubular brittle material having an inner surface of high surface precision with a maximum roughness Rmax of 0.1 ?m or smaller and a center line average roughness Ra of 0.01 ?m or smaller, and to provide a tubular brittle material with high precision using said polishing method. The polishing method according to the invention is characterized by that the inner surface of the tubular material being pre-cut into a tubular shape using a honing machine is further polished with a sheet material having diamond abrasives attached thereon. Also claimed is a tubular brittle material obtained by said polishing method.

Abstract: A known quartz glass crucible for crystal pulling consists of a crucible wall, having an outer layer which is provided in an external area thereof with a crystallisation promoter which results in crystallisation of quartz glass, forming cristobalite when the quartz glass crucible is heated according to specified use in crystal pulling. The aim of the invention is to provide a quartz glass crucible which has a long service life. As a result, the crystallisation promoter contains, in addition to a silicon, a first component which acts as a reticulating agent in quartz glass and a second component which is free of alkali metals and which acts as an agent forming separating points in quartz glass. The above mentioned components are contained and incorporated into a doping area (8) of the outer layer (6) having a layer thickness of more than 0.2 mm.

Abstract: Jacket tubes of synthetically produced quartz glass as a semi-finished product for producing an outer cladding glass layer of an optical fiber are generally known. The invention relates to an improvement of a jacket tube in terms of inexpensive producibility and of suitability as a semi-finished product for optical fibers having a low optical attenuation. According to the invention this object is achieved by a jacket tube in which the quartz glass has a content of metastable OH groups of less than 0.05 wt ppm and a content of anneal-stable OH groups of less than 0.05 wt ppm.

Abstract: An object is to provide a method for producing an optical synthetic quartz glass and an optical synthetic glass, having a birefringence of lower than 0.5 nm/cm and having favorable refractive index distribution, yet without lowering the productivity, as well as to provide an annealing furnace suitably used in practicing said method. In a step of raising the temperature of a columnar optical synthetic quartz glass preform to a temperature of from 800° C. to 1200° C., and after keeping for a definite time, lowering the temperature, the temperature is lowered with a temperature difference of from 1 to 20° C. between the temperature of the light transmitting surface of the optical synthetic quartz glass preform and the temperature of the outer peripheral side surface of the optical synthetic quartz glass preform at temperature-lowering rates of from 2 to 50° C./hour, respectively.

Abstract: An object of the present invention is to overcome the problems of the prior art technique, and to provide a heat treatment method as well as a heat treatment apparatus capable of heat treating, with higher efficiency, a synthetic quartz glass for optical use having higher homogeneity and higher purity. Another object of the present invention is to provide and a synthetic quartz glass for optical use.

Abstract: On the basis of a known process for the production of a preform for an optical fiber for optical data transmission technology, the productivity of the process for the production of complex refractive index profiles is to be improved by providing a quartz glass substrate tube which exhibits different doping in radial direction, introducing a core glass made of synthetic quartz glass into the substrate tube and covering the substrate tube with a jacket tube. A substrate tube suitable therefor is also being provided which tube requires less core glass material for the production of the preform, whether during the internal deposition or for the core glass rod in the rod-in-tube technique.

Abstract: The present invention relates to a quartz glass blank for an optical component for transmission of ultraviolet radiation of a wavelength of 250 nm or shorter, and to a use of the quartz glass blank in microlithography in combination with ultraviolet radiation of a wavelength of 250 nm or shorter. Moreover, the invention relates to a procedure for manufacture of the quartz glass blank. A quartz glass blank of the described type should show little induced absorption and be optimized with respect to compaction and decompaction. The quartz glass blank according to the invention is characterized by the following properties: a glass structure essentially free of oxygen defect sites, an H2-content in the range of 0.1×1016 molecules/cm3 to 4.0×1016 molecules/cm3, an OH-content in the range of 125 wt-ppm to 450 wt-ppm, an SiH group-content of less than 5×1016 molecules/cm3, a refractive index inhomogeneity, ?n, of less than 2 ppm, and a stress birefringence of less than 2 nm/cm.

Abstract: The present invention relates to a quartz glass blank for an optical component for transmission of ultraviolet radiation of a wavelength of 250 nm or shorter, and to a use of the quartz glass blank in microlithography in combination with ultraviolet radiation of a wavelength of 250 nm or shorter. Moreover, the invention relates to a procedure for manufacture of the quartz glass blank. A quartz glass blank of the described type should show little induced absorption and be optimized with respect to compaction and decompaction. The quartz glass blank according to the invention is characterized by the following properties: a glass structure essentially free of oxygen defect sites, an H2-content in the range of 0.1×1016 molecules/cm3 to 4.0×1016 molecules/cm3, an OH-content in the range of 125 wt-ppm to 450 wt-ppm, an SiH group-content of less than 5×1016 molecules/cm3, a refractive index inhomogeneity, ?n, of less than 2 ppm, and a stress birefringence of less than 2 nm/cm.

Abstract: A display apparatus for displaying projected images to a user comprises an enclosure with an aperture between the interior and exterior of the enclosure. A projector adjacent the aperture projects light through the aperture and against a screen surface to form an image that is visible to the user at a viewing station. A mask blocks the light from the projector proceeding to the eyepoint of the user. The method of the invention comprises projecting an image through the aperture onto the projection screen and blocking a portion of the light that is scattered from the last lens surface with the mask while permitting the image to proceed to the projection screen to be viewed.

Abstract: It is an object of the present invention to provide a hydrogen-doped silica powder that is useful in the formation of a quartz glass crucible that is capable of pulling a silicon single crystal without causing a state having dislocations in the silicon single crystal due to peeling of quartz glass segment. It is a further object of the invention to provide a quartz glass crucible for use in pulling a silicon single crystal whose inner surface is formed by use of the hydrogen-doped silica powder and a producing method of the silica powder.

Abstract: The present invention concerns a quartz glass blank for an optical component for the transmission of ultraviolet radiation of a wave length of 250 nm and under, as well as its utilization in microlithography in connection with ultraviolet radiation of a wavelength of 250 nm and under. Such quartz glass blank is to have low induced absorption, while being optimized in respect of compaction and de-compaction. The quartz glass blank according to the invention has the following properties: A glass structure essentially free of oxygen defect sites; a H2 content in the range of 3×1017 molecules/cm3 to 2.0×1018 molecules/cm3; an OH content in the range of 500 weight ppm to 1000 weight ppm; a SiH group content of less than 2×1017 molecules/cm3; a chlorine content in the range of 60 weight ppm to 120 weight ppm; a refractive index inhomogeneity, ?n, of less than 2 ppm; and a stress birefringence of less than 2 nm/cm.

Abstract: An aircraft light assembly comprises a light apparatus configured to be supported in a space on the body of an aircraft. The apparatus has one or more light emitting diodes (13) generating visible light and an outer structure overlying the LEDs. The outer structure includes a light transmission portion through which visible light from the LEDs can pass, and a metallic portion with an outer surface exposed to the external airflow. A heat-transmitting connection thermally links the LEDs to the metallic portion so that heat from the LEDs flows to the outer surface and is dissipated to the external airflow. The light assembly is configured to be secured in a conventional socket for an incandescent navigation light bulb and to receive the electrical current supplied thereto by the aircraft electrical system. Civilian applications of the unit have only visible LEDs.

Abstract: This system and process for providing a rendered image of a virtual 3-D scene comprises an image generating system which stores therein data defining the 3-D scene. Responses to receiving control data such as viewing parameters, editing commands, or instructions to a software application working with the scene data, the visualization systems renders a pixel data image of the scene and transmits the pixel data over a data network, such as the Internet, to a user computer to be viewed on a display device, such as a monitor.

Abstract: In the known method for producing an optical fiber, a coaxial arrangement comprising a core rod and an outer jacket tube is elongated, the coaxial arrangement being supplied in a vertical orientation to a heating zone and being softened therein zonewise, starting with the lower end thereof, and the optical fiber being withdraw downwards from the softened portion, whereby an annular gap existing between core rod and jacket tube is collapsed. Starting therefrom, in order to provided a method which makes it possible to produce optical fibers with a minimum curl and at low costs, the invention suggests that a quartz glass cylinder treated mechanically to its final dimension and having an outer diameter of at least 100 mm should be used as the jacket tube. An optical fiber obtained according to the method is characterized in that without the action of external forces it assumes a radius of curvature of at least 6 mm.

Abstract: An optical system provides a higher resolution image, especially for use with a projection system, using a combiner formed of fiber optics each having an input end and an output end, with the fiber optics grouped together so that the combiner has one or more image input ends each configured to receive an image from an associated image source. The input images are combined to yield an output image at the other end of the combiner that is smaller in area than the sum of the input image areas, increasing resolution. According to an embodiment, the output image is also counter-distorted to compensate for the distortion of the image caused by the relay optics used in projection.