Fiber optic devices including volume Bragg grating (VBG) elements are disclosed. A fiber optic device may include one or more optical inputs, one or more VBG elements, and one or more optical receivers. Methods for manufacturing VBG elements and for controlling filter response are also disclosed. A VBG chip, and fiber optic devices using such a chip, are also provided. A VBG chip includes a monolithic glass structure onto which a plurality of VBGs have been recorded.

Light wavelength selectivity of thick periodic structures was, historically, studied first in x-ray diffraction on crystalline solids. It was recognized that such selectivity arises due to the coherent addition of the light energy diffracted by individual layers forming precisely spaced stacks, such as that of the atomic layers of a crystalline lattice. The name of phenomenon, "Bragg diffraction," was given in recognition of the studies of it performed by Bragg.
Later, largely the same behavior was observed during the diffraction of light at optical wavelengths on the acoustic waves of the appropriate frequencies created inside optically transparent solid media. Acoustic waves create a periodic modulation of the index of refraction of a dielectric material via perturbation of its density. As a result, an acoustic wave can be used to manipulate light based on its wavelength. Thus, it functions as a wavelength filter.
Acoustic perturbation, however, is of a temporal nature, and relaxes completely after its source is extinguished and with it disappears the filter. Long-lasting Bragg gratings were first utilized, perhaps, with the invention of full-color holography. It employed relatively thick films of dichromatic gelatins (DCG) for holographic recording of color-realistic images of 3-D objects by using lasers of different colors. Subsequent reconstruction of images with conventional white light sources became possible due to the wavelength selectivity property of volume Bragg gratings. However, to the inventors' knowledge, even though the wavelength selectivity of the volume Bragg gratings was the underlying mechanism that enabled white-light reconstruction of thick-layer DCG display holograms, their utility for separating, combining, or otherwise manipulating specific wavelengths of light with the intention of achieving practical device functionality has not been recognized.
Use of volume Bragg gratings (VBG) recorded in doped lithium niobate photorefractive crystals for filtering light at optical wavelengths was adopted in construction of solar and lidar filters used to isolate light at a particular wavelength from the broad band background. A principal issue, however, is that recording of such filters must be performed at the same wavelength at which the filter will subsequently operate. As a result, the use of these filters is limited to a very limited range of wavelengths where sufficiently powerful lasers exist. Furthermore, the list of appropriate recording materials is confined to two or three narrow classes of photorefractive materials, which often have physical properties that are unsuitable for their intended mode of operation. For example, no material is known to the inventors that would allow construction of practical functional fiber-optic devices that would utilize volume Bragg grating filters recorded at wavelengths in the range of about 800–1650 nm.
This drawback can be partially overcome in photorefractive lithium niobate crystals when a VBG filter is recorded through a different surface than that used for its operation. By using this approach, filters can be constructed in lithium niobate that can operate at wavelengths that are useful for practical photonic devices, such as, for example, fiber-optic devices. Nonetheless, this approach is still rather limited due to a number of factors. First, the usable wavelength range is limited to λop>n*λrec on the one side, and the near infrared absorption edge of the lithium niobate on the other. Also, for practical devices, the bandwidth of the filter Δλ is limited by the maximum refractive index modulation achievable in that material (or its dynamic range, Δn): Δλ<(λop)*Δn/2n. This factor substantially limits the usefulness of this type of filter. This approach also requires the use of at least two (and typically four) polished surfaces that are orthogonal to each other, which increases the complexity of the filter manufacturing process and its cost. Additionally, the wavelength of the filter is substantially fixed to the value determined by the angle between the recording beams in the holographic setup. As a result, the wavelength must be controlled precisely for any practical device and is, therefore, unique for a particular wavelength or information-carrying "channel" of light, which complicates the issues in manufacturing of these elements.

Fiber optic devices having volume Bragg grating elements


A static random access memory (SRAM) device including a substrate and an SRAM unit cell. The substrate includes an n-doped region interposing first and second p-doped regions. The SRAM unit cell includes: (1) a first pass-gate transistor and a first pull-down transistor located at least partially over the first p-doped region; (2) first and second pull-up transistors located at least partially over the n-doped region; and (3) a second pass-gate transistor, a second pull-down transistor, and first and second read port transistors, all located at least partially over the second p-doped region. A boundary of the SRAM unit cell comprises first and second primary dimensions having an aspect ratio of at least about 3.2.

The present disclosure relates generally to static random access memory (SRAM) devices and, more specifically, to an SRAM device having a high aspect ratio cell boundary.
The physical dimension of a feature on a chip is referred to as "feature size." Reducing the feature size on a chip permits more components to be fabricated on each chip, and more components to be fabrication on each silicon wafer, thereby reducing manufacturing costs on a per-wafer and a per-chip basis. Increasing the number of components in each chip can also improve chip performance because more components may become available to satisfy functional requirements.
SRAM devices are one type of device that may undergo such scaling to reduce manufacturing costs. SRAM is random access memory that retains data bits in its memory as long as power is being supplied. Unlike dynamic random access memory (DRAM), SRAM does not have to be periodically refreshed. SRAM also provides faster access to data than DRAM. Thus, for example, SRAM is frequently employed in a computer's cache memory, or as part of the random access memory digital-to-analog converters in video cards.
However, SRAM is more expensive than other types of memory. Thus, SRAM designers and manufacturers continually strive to reduce the costs of manufacturing SRAM devices. The scaling of features sizes discussed above is one of the means to achieve such cost reduction. However, scaling feature sizes is not the only means available to reduce SRAM manufacturing costs. For example, modifying the layout of features within an SRAM chip to further increase the packing density of SRAM cells within each chip can also reduce manufacturing costs.
Accordingly, what is needed in the art is an SRAM device and method of manufacture thereof that addresses the above discussed issues.

SRAM device having high aspect ratio cell boundary

Taiwan Semiconductor Manufacturing Company, Ltd.


A vehicle wheel axle assembly comprises an axle element with a first outer face and a second outer face and a clamping assembly including a clamping element and a gripping element. The gripping element includes an axially inwardly facing grip face and an axially outwardly facing pressure face. The clamping element includes a helical threaded portion and an axially inwardly facing clamping face. The clamping assembly includes an elastically resilient element to axially bias said grip face to be axially inward and distal from said clamp face. The pressure face is axially inboard of the clamping face. The gripping element is rotatable relative to said clamping element. The clamping element is rotationally coupled to the gripping element by a coupling means at a coupling interface.

Field of the Invention
The present invention relates to a vehicle wheel axle assembly, particularly including aspects that facilitate the connection between axle of a vehicle wheel and the frame to which the vehicle wheel is mounted. More specifically, the present invention relates to a vehicle wheel axle assembly with a threaded connection to the frame that includes a rotational coupling feature to restrict inadvertent loosening of this threaded connection. The present invention is particularly applicable to a bicycle wheel axle assembly that facilitates the connection between axle of a bicycle wheel and the frame of a bicycle.
Discussion of Prior Art
Heretofore, the prior art threadable axle assemblies for bicycles and similar vehicles (commonly referred to as "through-axles") are designed to work only with frames having "closed dropouts" with enclosed axial apertures to receive this through-axle. This arrangement requires that the through-axle be completely withdrawn from the frame in order to release the wheel from the dropouts. This renders this procedure as time consuming, complex, and clumsy, since the operator must now be able to manage three separate items: the bicycle, the wheel, and the through-axle.
Further, conventional through-axles rely on a generally fine pitch thread for this threadable assembly. This fine pitch arrangement provides good axial clamping to secure the axle assembly to the frame and also has a lower tendency to inadvertently unscrew or loosen. However, this fine pitch also requires many rotations of the through-axle to secure the axle assembly to the frame, which adds significant time the procedure of installing and removing the axle assembly (and wheel) from the frame. In contrast, a coarse pitch thread engagement has a steeper thread helix angle and thus considered a "faster thread" to axially advance the threaded engagement with fewer turns and greater speed than a fine-pitch thread. This rapid tightening/loosening of the through-axle saves precious seconds, particularly in race conditions.
Particularly in bicycle racing conditions, where seconds count, the added time and complexity of conventional through-axle is very problematic for the racer. This problem is significant enough that such through-axle systems have not been widely adopted in bicycle road-racing applications, where the ability to quickly swap out wheels (due to a flat tire, for instance) is particularly critical.
Further still, conventional through-axles commonly do not employ any locking features to restrict any inadvertent loosening or unthreading of this connection. Bicycles commonly experience a high degree of vibration, both on-road and off-road. This may induce the through-axle to loosen during the ride, which may permit the wheel to be wobbly in the frame, resulting in a wobbly connection and a reduction in control. Further loosening may cause the wheel to become inadvertently detached from the frame, a circumstance with potentially disastrous consequences.
Yet further, in the case where conventional slotted dropouts ("open dropouts") are utilized, the through-axle is not captured and proper wheel retention relies solely on the axial clamping between the axle assembly and the dropouts. In such a configuration, an axle that is inadvertently loosened may more easily result in the wheel becoming detached from the frame. As such, it is that much more critical that the axle assembly does not loosen from the frame.


The present invention provides a method for designing a frequency-shifting isolator system that includes selecting, an impact absorption envelope; a geometry for the isolator mount system; and an elastomeric dampening material formed in the selected geometry. The isolator mount system is preferably configured to shift frequencies at predetermined displacements upon impact, at or before the system attains resonance.

1. Field of the Invention
This invention relates generally to shock and vibration protection devices and systems, and more particularly to a technique for implementing frequency shifting isolator devices and systems that shift natural frequencies when approaching a resonance point.
2. Description of the Prior Art
Nearly all objects vibrate when hit, struck or somehow disturbed. Vibration of objects continues to pose a challenge for operators, especially in environments where sensitive equipments are connected to surfaces that may be subjected to impacts, shocks or unintended disturbances.
Materials having dampening properties are widely used in applications where shock and vibrations must be minimized. These materials are increasingly used in applications requiring minimal or no equipment failures due to impact forces or vibrations. Such applications include sports equipment, tools, electronics, automobiles, airplanes and the like. As an example, computers used in harsh, rugged environments may be damaged if adequate dampening materials and systems are not provided to address potential impacts and vibrations.
There have been advances in materials that offer dampening qualities, and their uses have been broadened. Some of these materials are suggested in U.S. Pat. No. 5,766,720, issued to Yamagishi, et al. on Jun. 16, 1998, and include natural rubbers, synthetic resins such as polyvinyl chlorides, polyurethanes, polyamides, polystyrenes, copolymerized polyvinyl chlorides, polyolefin synthetic rubbers, as well as urethanes, EPDM, styrene-butadiene rubbers, nitrites, isoprene, chloroprenes, polypropylene, and silicones.
Further, users of materials having impact absorption and shock isolation properties have long desired to understand how to better design products that can meet or exceed expected impact requirements, without the routine of trial and error testing after the products have already been manufactured. The present invention addresses these concerns.


Glass or crystal particles of nanocrystalline size having a minor dimension of 0.1 to 100 Angstrom units. They may be prepared by controlled thermal separation of phase-separable glasses. Preferred crystal forms are zinc pyrophosphate and lithium disilicate. A crystallizable glass is combined with phyllosilicate particles and sintered to form an oriented composite body. During slow sintering, the crystal grows epitaxially on the phyllosilicate.

The invention relates to glass and glass-ceramic particles of nanocrystalline size. It is further concerned with methods of producing materials of such minute particle size.
The term "nanocrystalline" refers to particles having a diameter or thickness on the order of a nanometer. More particularly, it is here used to refer to particles in the size range of 0.1 to 100 Angstrom units. Such minute particles are characterized by large surface areas, as measured by the nitrogen absorption (BET) method.
Particles of nanocrystalline size are of interest in diverse applications. In general, they react with each other, or with other materials, at lower temperatures than are normally required for the same reaction of such materials in a bulk state. Thus, they are of particular value in forming composite materials with either organic or inorganic reactants.
It is known to delaminate phyllosilicate materials to produce platelets of nanocrystalline size. It is a purpose of the present invention to provide particles of corresponding size from glass and glass-ceramic materials.


An acrylic rubber, comprising an alkoxyalkyl(meth)acrylate monomer unit in an amount of 70.1 to 99.8 wt %, a methacrylonitrile monomer unit in an amount of 0.1 to 9.9 wt % and a butenedionic acid monoester monomer unit in an amount of 0.1 to 20 wt %; and a cross-linkable acrylic rubber composition made by containing the acrylic rubber and a cross-linking agent. According to the invention, it is possible to provide a cross-linkable acrylic rubber composition having excellent scorch stability and an acrylic rubber cross-linked product, which can be obtained by cross-linking the cross-linkable acrylic rubber composition, having excellent heat resistance, cold resistance and fuel oil resistance.

Since an acrylic rubber has excellent heat resistance and oil resistance, etc., it is widely used as a material of rubber parts to be used in a state of contacting oil, etc., such as seals, hoses, tubes and belts, etc. in the automobile-related fields, etc. An acrylic rubber is subjected to cross-linking to obtain rubber elasticity so as to be used as these rubber parts. For that purpose, it is copolymerized with a cross-linkable monomer having an active cross-linking point normally in an amount of 1 to 5 wt % or so. Such a cross-6 linkable acrylic rubber is demanded to have small permanent compression set as well as excellent heat resistance and cold resistance and, furthermore, there has been a demand for those also having excellent fuel oil resistance and excellent scorch stability.
Selection of the cross-linkable monomer to be copolymerized with an acrylic rubber as well as a cross-linking agent to be used in combination therewith results in determining a cross-linking reaction speed, so that it affects storage stability, mechanical characteristics, permanent compression set and heat resistance, etc. Generally, as a cross-linkable monomer to serve as such a cross-linking agent, 2-chloroethylvinyl ether, vinylchloro acetate and other chlorine based monomers, allylglycidyl ether and other epoxy based monomers may be used.
As cross-linkable monomers, maleic acid, fumaric acid and other butenedionic acid monoesters, specifically, butenedionic acid monobutyl ester has been also studied. Among them, a cross-linked product of an acrylic rubber composition formed by including an aromatic diamine cross-linking agent and a guanidine compound cross-lining auxiliary in an acrylic rubber obtained by copolymerizing with 0.1 to 10 wt % of monolower alkyl ester of fumaric acid has been reported to exhibit excellent heat resistance and cold resistance (the patent article 1). However, these acrylic rubber compositions were poor particularly in scorch stability.
Also, it has been reported that when using an acrylic rubber composition obtained by copolymerizing alkoxyalkyl acrylate, acrylonitrile in an amount of 10 to 15 wt % and a necessary amount of cross-linkable monomer as an automobile fuel hose, fuel impermeability can be improved while maintaining sour gasoline resistance and amine resistance, etc. (the patent article 2). However, the composition has a disadvantage that the cold resistance and heat resistance become poor.
Furthermore, it is reported that a composition obtained by blending a specific cross-linking agent and a specific amine compound in a carboxyl group containing acrylic rubber including a specific structure unit derived from methacrylonitrile does not adhere to metal surfaces and does not cause scorch at the time of processing and that an obtained cross-linked product has excellent heat resistance, cold resistance and degraded oil resistance (the patent article 3). However, the composition does not have enough cold resistance and fuel oil resistance.
The patent article 1: The Japanese Unexamined Patent Publication No. H11-92614
The patent article 2: The Japanese Unexamined Patent Publication No. 2001-146540
The patent article 3: The Japanese Unexamined Patent Publication No. 2003-342437

Acrylic rubber and cross-linkable acrylic rubber composition


In order to suppress a reverse short-channel effect, a plurality of dummy gates, wherein gate electrodes are respectively to be formed, are formed in selective regions on the substrate. Further, the regions wherein first conductive type elements are to be formed are masked. Thereafter, a first conductive type well by ion planting a first conductive type impurity is formed. Further, a second conductive type source and drain region is formed by ion planting a second conductive type impurity. The resist covering the regions, wherein the first conductive type elements are to be formed, are removed. Following this, regions wherein second conductive type elements are to be formed, are masked by a resist. Further, a second conductive type well is formed by ion planting a second conductive type impurity. A first conductive type source and drain region is formed by ion planting a first conductive type impurity. Subsequently, the resist covering the regions wherein the second conductive type elements are to be formed, is removed, after which the source and drain regions are activated. Thereafter, a first layer on the substrate is formed, and the first layer is polished until the surface of each of the dummy gates is exposed. Then, the dummy gates are removed and, regions wherein the first conductive type elements are to be formed are masked. After a first conductive type impurity is implanted, the resist covering the regions wherein the first conductive type elements are to be formed is removed. Further, regions wherein the second conductive type elements are to be formed, are masked. Then, a second conductive type impurity is implanted, after which the resist covering the regions wherein the second conductive type elements are to be formed is removed. Further, a gate oxide layer in each recess is left by removing the dummy gate. Following this, after the substrate is covered with a gate electrode material, the gate electrode material covering the substrate is polished until the first layer is exposed.

1. Field of the Invention
The present invention relates generally to a method of fabricating a semiconductor device, and more specifically to a method of fabricating an n-MOSFET (metal-oxide-semiconductor field-effect-transistor) which features an effective suppression of reverse short-channel effects.
2. Description of the Related Art
As is known in the art, one of the most important subjects for MOS devices is a short-channel effect. A threshold voltage is determined by the space charge in a depletion layer formed under a gate electrode. However, in a short channel MOSFET, the charge is reduced because of a charge sharing with the drain field. For this reason, the threshold voltage of a short channel MOSFET is undesirably reduced.
In addition to the above mentioned short-channel effect, as the MOSFET channel length becomes smaller, another undesirable effect which is reverse to the short-channel effect, called a reverse short-channel effect. That is, as the channel length is reduced, the threshold level increases. This reverse short-channel effect will be described later.
Before turning to the present invention, a conventional method of fabricating an n-MOSFET is briefly described with reference to FIGS. 1A-1E, 2A-2B, 3A-F, and 4A-4E.
Referring to FIGS. 1A-1E, processes of fabricating a MOSFET are shown.
As shown in FIG. 1A, a plurality of element isolating regions 61 are formed at predetermined portions of a p-type semiconductor substrate 60. Thereafter, a suitable resist 62 covers a region to which an n-MOSFET is to be formed. Following this, an n-type impurity is ion implanted to the region thereby to form an n-well 64. At the same time, n-type impurities are also ion implanted to the same region to adjust a threshold voltage of. p-MOSFET.
Further, as shown in FIG. 1B, a p-MOSFET forming region is masked using a resist 65, after which a p-type impurity is ion implanted to the region in order to form a p-well 67. At the same time, the p-type impurity is also ion implanted to the p-MOSFET forming region to adjust a threshold voltage of the n-MOSFET.
Subsequently, as shown in FIG. 1C, a gate oxide 68 and a polycrystalline silicon 69 are deposited in this order on the p-type substrate 60, after which gate electrodes 70 are formed using photolithography and etching techniques.
Then, as shown in FIG. 1D, after the n-well 64 is masked with a resist 71, an n-type impurity is ion implanted to the p-type well 67 thereby to form a n-type source-drain region 73. On the contrary, as shown in FIG. 1E, after the p-well 67 is masked with a resist 74, a p-type impurity is ion implanted to the n-type well 64 thereby to form a p-type source-drain region 76. Following this, after the resist 74 is removed, the substrate is annealed in an atmosphere of nitrogen for activating the source-drain regions 73 and 76. The annealing is to repair lattice damage and put dopant atoms on substitutional sites where they will be electrically active.
However, in the processes shown in FIGS. 1A-1E, while the source-drain regions 73 and 76 are subject to heat treatments (viz, annealing) for being activated, point defects in interstitial sites in the source and drain regions are liable to combine with boron ions and diffused in an accelerated manner along the direction of channel. Thus, as the channel length becomes shorter, the concentration of boron immediately below the channel becomes higher. As a result, threshold voltages of MOSFETs become higher. This phenomenon is called a reverse "short-channel" effect.
On the contrary, with MOSFETs, as the channel length is reduced, the depletion layer widths of the source and drain junction become comparable to the channel length, whereby the threshold voltage of the MOS device is lowered (short-channel effect).
In the case where the above mentioned two effects occur at the same time, it is extremely difficult to control the threshold voltage. Therefore, it is highly desirable to effectively suppress the anti-short-channel effect.
One known approach to suppressing the reverse short-channel effect is to implement ion implantation for forming the source-drain regions, which follows the annealing for activation of the source-drain regions. Subsequently, the ion implantation for adjusting the threshold voltage is carried out. Such a known technique is described with reference to FIGS. 2A and 2B.
As shown in FIG. 2A, a gate oxide layer 81 and a gate polysilicon electrode 82 are formed onto a p-type substrate 80 using known techniques. Subsequently, an n-type impurity such as As.sup.30 is implanted into the substrate 80 thereby to form a source-drain region 84. Thereafter, the substrate 80 undergoes annealing at 1000.degree. C. for 10 seconds. Following this, as shown in FIG. 2B, an p-type impurity such as B.sup.30 is implanted, via the gate polysilicon electrode 82 and the gate oxide layer 81, into the substrate 80 thereby to adjust a threshold voltage.
With the conventional technique shown in FIGS. 2A and 2B, the ion implantation for adjusting the threshold voltage is implemented after annealing the source-drain region 84 and thus, the reverse short-channel effect is able to be suppressed. However, in order to adjust the threshold voltage, the dopant is implanted through the gate oxide 81 into the substrate. Therefore, this prior technique suffers from the problem that the reliability of the gate oxide 81 is undesirably degraded.
In order to overcome the difficulty inherent in the second prior technique, it is necessary to form the gate oxide layer after the processes of the annealing and the ion implantation for adjusting the threshold voltage. Such a known technique, disclosed in Japanese Laid-open patent application No. 4123439. This third prior art however suffers from the problem in that when an oxide is formed on source and drain regions, the substrate is exposed to aluminum. Therefore, the aluminum forms an energy level which deteriorates the characteristics of the device. Further, an SiO.sub.2 film of this prior art is grown in a liquid phase and thus the quality of the film is degraded. As a result, in order to solve the above mentioned problems, it is necessary to use using a CVD technique for forming an oxide film on a source and drain region. A prior method using the CVD technique is disclosed in Japanese Laid-open Patent Application No. 4123439. However, this prior art is encountered the difficulty of a large number of fabrication processes.

Method of fabricating a MOSFET featuring an effective suppression of reverse short-channel effect


The Invention relates to a method for the manufacture of a smart label web. The smart label web comprises smart labels placed one after another and/or side by side and comprising a circuitry pattern and an integrated circuit on a chip therein. In the method, an electrical contact is formed between the integrated circuit on a chip and the circuitry pattern of the smart label in the smart label web in such a way that a structural part separated from a separate carrier web and comprising an integrated circuit on a chip is attached to the smart label. The structural part contains a thermoplastic material whereby it is attached to the smart label.

For attaching an integrated circuit on a chip in such a way that it is in electrical contact with a circuitry pattern, methods are known for direct attachment of the chip by flip-chip technology. Alternatively, the chip can be attached in such a way that a separate structural part, onto whose surface the chip is attached, is connected to the smart label.
A method is known from the publication U.S. Pat. No. 5,810,959, in which a substrate and a silicon chip are attached by means of an anisotropic conductive thermosetting adhesive by using heat and pressure.
Publication U.S. Pat. No. 5,918,113 discloses a method, in which an anisotropic conductive adhesive is applied onto a circuit board. The adhesive contains a thermoplastic or thermosetting resin and conductive powder dispersed therein. The adhesive layer is softened, and a semiconductor chip is adhered to it on application of heat and pressure.
From the publication U.S. Pat. No. 5,918,363, a method is known in which integrated circuits formed on a wafer are tested to determine whether they are functional. An underfill is applied on the functional integrated circuits, and the chips are separated from each other. The underfill can contain a thermoplastic substance. After this, the silicon chips are connected to their location of use in such a way that the underfill is spread around the electric connections.
From the publication U.S. Pat. No. 5,936,847, an electronic circuit is known in which there is a non-conductive polymer layer forming an underfill between a substrate and a chip. The polymer layer is provided with openings for electrical contacts. The substrate is also provided with openings, through which a conductive polymer is injected to form an electrical contact between the substrate and the chip.
The publication U.S. Pat. No. 6,040,630 discloses a connection for a chip which can also be disconnected, if necessary. On a substrate having a circuitry pattern formed on the substrate, a thermoplastic film is positioned, the film exposing the bumps of the chip. The thermoplastic film forms an underfill for the chip, and when the film is heated, it connects the chip and the circuitry pattern.
A method is known from the publication U.S. Pat. No. 6,077,382, in which an anisotropic conductive thermosetting adhesive is placed on a circuit board, and the circuit board is heated to a temperature which is lower than the setting temperature of the adhesive. A semiconductor chip is placed in its position and attached by means of heat and pressure.
Methods based on flip-chip technology have for example the following disadvantages:                the production line is complicated, expensive and inconvenient in view of further development, because all the operations are integrated on the same line, and        the placement of the chip on the smart label requires that the tool used has a long path and also that the chip is positioned very precisely in the correct location.
The smart label can also be provided with a separate structural part comprising an integrated circuit on a chip, attached on a film material.
The electrical contact between the integrated circuit on the chip and the circuitry pattern of the smart label is formed so that the film material of the separate structural part is impregnated with a conductive layer which is connected to the chip and which layer is brought into contact with the circuitry pattern in connection with the manufacture of the smart label by connecting both ends of the strip-like structural part to the circuitry pattern. That is, the structural part is off the smart label in the area between its ends. The structural part is attached to that side of the smart label on whose opposite side the circuit pattern is located so that the chip comes against the smart label.
The above-mentioned methods involve for example the following problems:                the techniques of attaching the structural part are unsophisticated and complex,        the materials presently used require long processing times, for which reason a significant difference is not achieved in the production rate when compared with flip-chip technology,        due to the slow processes, lines for single process steps become relatively complex and expensive,        the mechanical techniques for connecting the structural parts, such as crimp connections, restrict the material choices and may also cause problems of reliability,        in some existing smart labels, the distance between the structural part and the circuitry pattern and simultaneously the distance between the integrated circuit on the chip and the circuitry pattern are changed by bending, because the structural part is not wholly attached to the smart label, wherein the stray capacitance affecting the frequency of the electrical oscillating circuit is changed, and        the smart label has a relatively thick construction, which is disadvantageous in further processing steps.

Smart label web and a method for its manufacture


A new and useful traverse rod structure, designed to maintain or improve the functionality of a traverse rod, while improving the aesthetics of the traverse rod is provided. The traverse rod is designed to improve the functionality of the rod, while minimizing the risk of damaging the aesthetic features of the traverse rod as the hanging object is manipulated. Still further, the traverse rod is designed with an attractive and aesthetic external appearance. In addition, the traverse rod is designed to be efficient to assemble and operate. In its preferred form, a traverse rod comprises (a) a longitudinally extending tube having an opening extending along the tube, (b) a longitudinally extending track located within the tube, the track comprising a pair of substantially co-planar track sections with a gap therebetween, and (c) one or more moveable carriers each of which is configured to engage a wall covering. Each moveable carrier has a follower extending through the opening in the tube. The follower has a first portion located at least partially in the gap in the pair of track sections and engaging the pair of substantially co-planar track sections such that the follower can ride along the track, so that the moveable carrier can be selectively moved along the tube. The foregoing structure is configured to provide the traverse rod with an aesthetic external appearance, provide a traverse rod that is efficient to assemble and operate, and in a way that maintains the aesthetic appearance of the traverse rod, as well as any surface ornamentation on the components of the traverse rod.

The present invention relates to traverse curtain rod structure, that is designed to provide an efficient structure for supporting and manipulating a hanging curtain, drape, wall covering, etc., while also minimizing the risk of damaging the aesthetic features of the curtain rod, as the hanging curtain, drape, wall covering, etc., is being manipulated.
Traverse curtain rods typically are designed to support a hanging object (e.g. a curtain, drape, wall or window covering, etc.), and to enable the hanging object to be manipulated over the span of a wall or ceiling. Such traverse curtain rods may also have various features that are designed to enhance their aesthetic appeal. For example, they may be painted or have other forms of surface decorations. They may also have decorative finials at their ends, that further enhance their aesthetic appeal
In order to manipulate a hanging object from a traverse curtain rod, and particularly a relatively heavy object such as a curtain or drape, it is known to provide a traverse cord that is supported by the traverse rod, and connected to the hanging object. The traverse cord is manipulated to draw the hanging object along the span of the traverse rod. In some instances, a traverse cord is not provided or is not used, and the hanging object, which effectively connects the carriers, is grasped and pulled, in order to move the hanging object along the traverse rod.
In the applicants' experience, there is a need to improve the structure of a traverse rod, to maintain or improve the manner in which a hanging object is moved along the span of the traverse rod. Moreover, there is a need to maintain or enhance such functionality, while minimizing the risk of damaging the aesthetic features of the traverse rod as the hanging object is manipulated. For example, if the traverse rod is painted or has some other form of decorative surface ornamentation, applicants believe it is useful to provide for efficient manipulation of the hanging object, while avoiding contact between the object and the rod surface that can wear the surface ornamentation of the rod. Moreover, applicants believe it is desirable to provide a traverse rod that is efficient to assemble and operate.
Specifically, in applicants' experience, certain rods on that market that are decorative with traversing capabilities have only ½ rings. The openings are on the back side of the rod. The rings have a carrier that runs on a track on the backside of the rod and then this glide hangs below the rod, where the drapery pins into. Thus, the carrier can be seen above the drapery top.
Other traverse ornamental type rods of which applicants are aware are made out of thin metal and telescope out. Applicants believe this style is dated and doesn't have the capabilities of the new massive look of the rod and rings, that customers want or need. A center support is needed for this type of rod between every 3 to 4 feet. This is why the rings can only be ½ around. The parts in this type of rod are thin metal and plastic type parts and pieces.
Still other ornamental rods that are presently on the market have metal rings and are hand drawn, with batons. The problem with such rods is that it is very difficult to draw the draperies open and closed. It is almost impossible on a window, when the top of the window is 7 feet from the floor. When you need or want to cover a window where the top of the window maybe anywhere from 7 to 12 feet off the floor, you cannot move the drapes without tearing the fabric after awhile. Getting on a chair can only help if top of window is 8 feet or less from the floor. When you go to open or close the drapes it is very difficult to move rings with the baton, without tearing fabric, struggling with opening and closing of drape. The rings tip and wear off the finish on the rods because it is sliding and bumping the rod. The rings don't move smoothly on the rod they tend to grab the rod and stick and bind. This lends itself to tearing of the fabric. Most of the time people get very annoyed and put the drape in one position and leave them there, then they have a nice look of the rod and rings but they don't have any functioning of the drapery on the rod.


A low cost, compact projection display source that serves as a very bright image source for an automotive head up display. The present invention is comprised of a high intensity halogen light source and a liquid crystal display. The liquid crystal display is controlled by display electronics that write images onto the liquid crystal display that are to be displayed to the driver or passengers of a vehicle. Light output from the high intensity light source is transmitted through a piece of infrared energy absorbing glass, a decentered lens, such as a Fresnel lens, and a diffuser that uniformly backlights the liquid crystal display. Crossed polarizers are used on either side of the liquid crystal display. The high intensity light output transmitted by the liquid crystal display is passed through a yellow-orange output window which is projected onto a toric combiner for display to the driver of the vehicle. A fan provides cooling for the liquid crystal display and display circuitry that interfaces between the display electronics and the liquid crystal display. The projection display source produces a very high contrast (very bright) image source without heat problems. The projection display source is capable of producing 20,000 foot-lamberts of light energy output. The projection display source is the brightest known image source for non-military head up displays of either the non-reconfigurable or reconfigurable variety. The yellow-orange color used for the output window of the projection display source is used to maximize color contrast with the display background.

The present invention relates to head up displays, and more particularly, to a high intensity head up display image source for use with head up displays, and the like.
In recent years, there has been a great deal of effort relating to the development of head up displays for use in automotive vehicles. For example, the assignee of the present invention has developed a head up display system for use by law enforcement personnel, for example. This head up display system provides for virtual display of images and data derived from a number of sources, including radar, television, and a mobile data terminal that is linked by way of a communications link to law enforcement computers. However, it has been found that a high brightness image source is required for optimum performance of the system under high ambient light conditions encountered during daytime use.
The closest prior art in terms of brightness is a vacuum fluorescent display (VFD) image source. The vacuum fluorescent displays are non-reconfigurable. The brightest VFD provides a light output of about 7,000 foot-lamberts. Heretofore available head up display sources have not produced images at high brightness levels.
Therefore, it is an objective of the present invention to provide for a high brightness image source for use in head up display systems, and the like.

Head up display with a lens decentered to the optical axis of the illumination


Transmitter apparatus to broadcast coded orthogonal frequency-division multiplexed (COFDM) radio-frequency carriers conveying low-density parity-check (LPDC) coding transmits the same coded DTV signals twice some time apart. The coded DTV signals of initial transmissions and of final transmissions are mapped to quadrature amplitude modulation (QAM) of the COFDM carriers according to first and second patterns, respectively. Bits that map to lattice points in the first mapping pattern more likely to experience error are mapped to lattice points in the second mapping pattern less likely to experience error. Bits that map to lattice points in the second mapping pattern more likely to experience error are mapped to lattice points in the first mapping pattern less likely to experience error. Receiver apparatus combines the earlier and later transmissions of twice-transmitted COFDM signals as part of iterative procedures for de-mapping QAM and decoding the LDPC coding of the DTV signals.

DTV broadcasting in the United States of America has been done in accordance with broadcasting standards formulated by an industry consortium called the Advanced Television Systems Committee (ATSC), which standards have prescribed the use of a vestigial-sideband amplitude-modulated single carrier in each radio-frequency (RF) channel allocated for broadcasting DTV signals. Consideration is being given to replacing those DTV broadcasting standards with new standards that may prescribe coded orthogonal frequency-division multiplexed (COFDM) plural carriers in each RF channel allocated for broadcasting DTV signals. These new standards may, for example, resemble the DVB-T2 broadcasting standard developed for use in Europe.
COFDM is typically generated beginning with randomizing digital data to insure that subsequent encoding of forward-error-correction (FEC) coding receives sufficient density of logic ONEs to operate efficiently. Then, the resulting FEC coding is subjected to some form of bit interleaving, and the bits of the interleaved FEC coding are mapped to quadrature-amplitude-modulation (QAM) symbol constellations. The real-axis and imaginary-axis spatial coordinates of the QAM symbol constellations are parsed into orthogonal frequency-division multiplex (OFDM) symbols, which modulate a single carrier wave at high rate using quadrature-amplitude-modulation (QAM). The resulting modulated carrier wave is then transformed in a fast inverse discrete Fourier transform (I-DFT) procedure to generate a multiplicity of RF carrier waves uniformly distributed within the frequency spectrum of the RF channel, each of which RF carriers is modulated at low symbol rate. (In this specification and the accompanying drawing and claims the general term "QAM" is to be considered to include QPSK, QPSK being an alternative term for 4QAM.)
Reception of COFDM generated as described in the foregoing paragraph will fail if there is severe flat-spectrum fading of substantial duration. Such flat-spectrum fading is sometimes referred to as a "drop-out" in received signal strength. Such drop-out occurs when the receiving site is changed such that a sole effective signal transmission path is blocked by an intervening hill or structure, for example. Because the signaling rate in the individual OFDM carriers is very low, COFDM receivers are capable of maintaining reception despite drop-outs that are only a fraction of a second in duration. However, drop-outs that last as long as a few seconds disrupt television reception perceptibly. Automatic gain control of the front-end tuner stages of a DTV receiver will increase their gain, amplifying noise to introduce burst noise into the FEC coding. Such protracted drop-outs are encountered in a vehicular receiver when the vehicle passes through a tunnel, for example. By way of further example of a protracted drop-out in reception, a stationary receiver may briefly discontinue COFDM reception when receiver synchronization is momentarily lost during dynamic multipath reception conditions, such as caused by an aircraft flying over the reception site. Electric motors can generate radio-frequency noise strong enough to overload the front-end tuner stages of a DTV receiver, acting as a jamming signal that obliterates COFDM reception and generates burst noise too long to be corrected by FEC coding.
The DVB-T2 standard for DTV broadcasting prescribes Bose-Chaudhuri-Hocquenghem (BCH) coding concatenated with subsequent low-density parity-check coding (LPDC) as FEC coding. The concatenated BCH-LDPC coding prescribed in the DVB-T2 standard is reported to allow better performance in the presence of AWGN to be achieved using 256QAM symbol constellations than could be achieved with DVB-T using 16QAM symbol constellations. The bits of the LDPC coding are block interleaved using a modification of matrix type of interleaving in which successive bits of LDPC coding are arranged in columns for subsequent row-by-row utilization for mapping to lattice points within successive QAM symbol constellations, which modification introduces "column twist". The DVB-T2 standard authorizes an alternative to parsing the real-axis and imaginary-axis spatial coordinates of 16QAM or 64QAM symbol constellations directly into orthogonal frequency-division multiplex (OFDM) symbols. In this alternative these QAM symbol constellations are in effect rotated relative to the real and imaginary axes of coordinate space so that every one of the lattice points of successive QAM symbols has unique coordinates along both the real axis and the imaginary axis. The unique coordinates of each QAM symbol constellation along the imaginary axis are then delayed for transmission respective to the unique coordinates of that QAM symbol constellation along the real axis. Accordingly, two unique coordinates of each QAM symbol constellation are transmitted, the second transmission being delayed respective to the first transmission for a time longer than the duration of a QAM symbol of an individual carrier. This facilitates iterative-diversity reception that can often avoid complete loss of reception of a portion of DTV signal owing to flat-spectrum fading, despite signal drop-outs that last up to a second or so.
An alternative way to facilitate iterative-diversity reception that can avoid complete loss of reception of a DTV signal owing to flat-spectrum fading, despite signal drop-outs that last up to a few seconds, is single-time retransmission of complete QAM symbol constellations after a suitable interval. Obviously, ignoring effects of signal corruption arising from noise in the transmission channel, twice transmitting complete QAM symbol constellations halves digital payload compared to transmitting them once.
When superficially considered, rotation of the QAM symbol constellations respective to the real and imaginary axes of modulation signal space appears not to reduce digital payload compared to a single-time transmission. Also, the respective times at which the initial transmission of a mapping of a set of data bits occur and at which the subsequent retransmission of a mapping of that same set of data bits occur are automatically referenced respective to each other.
However, the sizes of the data-slicing bins of the I-axis coordinates are reduced from what they would be for the square QAM symbol constellation without rotation. Also, the sizes of the data-slicing bins of the Q-axis coordinates are reduced from what they would be for the square QAM symbol constellation without rotation. E. g., the sizes of the data-slicing bins would be reduced by a factor of four when 16QAM symbol constellations are rotated. Reduction in the size of the data-slicing bins results in more bit errors being caused by AWGN corrupting the QAM. U.S. Pat. No. 8,958,490 granted 17 Feb. 2015 to A. L. R. Limberg, titled "COFDM broadcasting with single-time retransmission of COFDM symbols" and incorporated herein by reference points out the following. The reduced-size data bins are substantially the same size as those for non-rotated 256QAM symbol constellations. The number of bit errors in data slicing that are caused by AWGN corrupting the non-rotated 256QAM symbol constellations is substantially the same as the number of bit errors in data slicing that are caused by AWGN corrupting the rotated 16QAM symbol constellations. The number of data bits that can be mapped by each of the rotated 16QAM symbol constellations is four. The number of data bits that can be mapped by each of the non-rotated 256QAM symbol constellations is eight, and single-time retransmission of the non-rotated 256QAM symbol constellations results in the same eight data bits being conveyed over two COFDM symbol block intervals. Whichever of the two methods is used to transmit data twice, two COFDM symbol block intervals convey on average eight data bits times the number of QAM symbol constellations in each COFDM symbol block interval. I. e., for given size of data-slicing bins and given number of bit errors in data slicing that are caused by similar AWGN, single-time retransmission of 256QAM symbol constellations results in similar code rate as rotated 16QAM symbol constellations do.
When the Q-axis coordinates of rotated 16QAM symbol constellations are delayed respective to their I-axis coordinates, the OFDM carriers are no longer each modulated in accordance with a respective rotated 16QAM constellation. Instead, each OFDM carrier is modulated in accordance with a respective 256QAM constellation. Presuming the 16QAM symbol constellations each used Gray mapping, the 256QAM symbol constellations are not Gray-mapped. The coordinates for the two orthogonal axes in which data-slicing is done are not Gray-coded, nor are they independent of each other. So, de-mapping rotated 16QAM constellations in a DTV receiver involves two-dimensional metrics for estimating errors in each of the four de-mapped bits to support subsequent soft decoding procedures for the FEC coding. This is a much more challenging task than de-mapping 256QAM symbol constellations that are Gray-mapped and have independent coordinates for the two orthogonal axes in which data-slicing is done. These independent coordinates are Gray-coded and de-mapping involves two sets of one-dimensional metrics for estimating errors in each of the eight de-mapped bits to support subsequent soft decoding procedures for the FEC coding. Errors can be estimated quite simply, proceeding from the departures of data-slicing results from values associated with lattice points in a 256QAM symbol constellation uncorrupted by noise.
Initial and final transmissions of the same coded data often allows a DTV receiver to replace burst noise in one of those transmissions with coded data from the other one of those transmissions. So, single-time retransmission of the same coded data facilitates the receiver being provided with substantial capability for overcoming peaks in noise of additive white Gaussian noise (AWGN) character, such as Johnson noise, as well as exceptionally effective capability for overcoming burst noise of substantial duration. This capability for overcoming burst noise facilitates the use of concatenated BCH-LDPC coding being used as FEC coding. LDPC coding is effective for overcoming AWGN, doing so at code rates almost three times those of concatenated convolutional coding (CCC) similarly effective for overcoming AWGN. LDPC coding does not have the tendency to extend burst errors that CCC has. However, LDPC coding is not very effective for correcting burst noise. While BCH coding can correct burst errors, using the BCH coding to correct a good amount of burst error distributed through each lengthy LDPC codeword requires many parity bits being associated with the systematic bits of the LDPC codeword. This undesirably reduces overall code rate of the concatenated BCH-LDPC coding. The DVB-T2 standard prescribes BCH coding capable of correcting only 10 or 12 bits in a block of 7,200 to 541,000 bits, keeping the number of parity bits per block less than 200. Accordingly, the retransmission provided by dissecting rotated symbol constellations is the principal mechanism allowing a receiver to correct burst noise in its reception of transmissions from a single COFDM transmitter. The primary reason that BCH coding was employed in DVB-T2 was to overcome the so-called "floor" in rate of reduction of bit-error-rate (BER) that occurs for signals having higher signal-to-nose ratio (SNR).
If a reception site is not more than a few kilometers distant from the COFDM transmitter or transmitters, multipath reception can cause severe frequency-selective fading of a large group of OFDM carriers in a particular portion of the RF channel. Frequency-selective fading has been observed that extends over three MHz in a 6-MHz-wide RF channel and reduces the amplitude of a central few of the selectively faded OFDM carriers as much as 35 dB respective to less affected OFDM carriers. Such frequency-selective fading corrupts so many of the QAM symbols used for modulating respective OFDM carriers that de-interleaving of the results of de-mapping the QAM symbols is unable to reduce the density of bit errors in the recovered bit-wise FEC coding to permit successful decoding thereof. In some circumstances a directional reception antenna may be able to mitigate this problem. However, the whip antenna of a hand-held receiver is apt not to have appreciable capability for rejecting co-channel interference.
U.S. Pat. No. 8,958,490 discloses the following procedures to overcome severe frequency-selective fading of a large group of OFDM carriers in a particular portion of the RF channel. COFDM symbols of initial transmissions of the coded DTV data are arranged such that their circular discrete Fourier transforms (DFTs) are rotated one-half revolution respective to the circular DFTs of corresponding COFDM symbols in time-slices of subsequent transmissions of that same DTV data. DTV receivers then de-rotate the COFDM symbols of initial transmissions of the DTV data and after delaying the resulting COFDM symbols combine them with COFDM symbols of subsequent transmissions of that same DTV data. Such DTV receivers are capable of overcoming severe frequency-selective fading that is apt to be caused by multipath reception from nearby DTV transmitters, as well as overcoming protracted severe flat-spectral fading of one of the initial and subsequent transmissions of the same DTV data.
Delaying the final transmissions of coded DTV signals up to few seconds respective to the initial transmissions of them allows receivers of suitable design to overcome protracted drop-outs in received signal strength. However, retransmitting COFDM symbols without intervening delay, or with intervening delay of only a few OFDM symbol intervals, enables receivers of suitable design better to overcome randomly occurring burst noise of short duration.
U.S. Pat. No. 8,958,490 describes COFDM receivers that decode separately the FEC coding of initial transmissions and final transmissions for iterative-diversity reception; data packets without error or with as little error as available are then chosen from the results of such separate decoding. U.S. Pat. No. 8,958,490 also describes COFDM receivers that use maximal-ratio code combining of the coordinates of corresponding QAM symbol constellations from the initial and final transmissions of iterative-diversity reception prior to QAM de-mapping of those constellations.
The single-level LDPC block coding prescribed in the DVB-T2 DTV broadcast standard was originally designed for satellite transmission systems employing multiple-phase-shift-keying (MPSK) modulation of COFDM carriers. Single-level LDPC block coding is not optimal for uniform quadrature amplitude modulation (QAM) of COFDM carriers insofar as overcoming AWGN is concerned, since the bits of the received QAM symbols do not all have similar likelihoods of error. One prior-art approach taken to alleviate this problem is to use a plurality of various strength LDPC codes in a multi-level coding (MLC) scheme. The design of appropriate component LDPC block codes and implementation of decoders for them present problems with this approach, especially for higher order QAM constellations having larger numbers of lattice points in them.
Replacing uniform QAM of COFDM carriers with non-uniform quadrature-amplitude modulation (NUQAM) of the COFDM carriers is another prior-art approach taken to alleviate single-level LDPC block coding not being optimal for overcoming AWGN when uniform QAM of COFDM carriers is used. The problem with this approach is difficulty with the digital partitioning of received signals into regions mapping bits with equal likelihoods of them being correct.

Iterative-diversity COFDM broadcasting with improved shaping gain


A hard surface cleaner having a cleaning head with rotational assist. In one embodiment, the cleaning head includes a housing having a fluid-supply and vacuum inlets. The housing also includes at least one flow-control inlet arranged with the vacuum inlet to draw a flow of air into the housing through the flow-control inlet. The cleaning head further includes a spray assembly at least partially enclosed within the housing. The spray assembly includes a shaft, at least one spray nozzle operably coupled to the shaft, and a plurality of fins also operably coupled to the shaft. The spray nozzle is configured to receive a pressurized fluid from the fluid-supply inlet and to rotate about the shaft by delivering the pressurized fluid toward a floor surface. The fins are positioned at least partially within the flow of air through the flow control inlet to control the rotational speed of the spray assembly.

Conventional devices have been developed to clean hard surfaces using a cleaning head with a rotating spray bar that directs pressurized water toward the target surface. One drawback with such devices is that high pressures can damage delicate surfaces. Lowering the pressure, however, decreases the rotational speed of the spray bar, making these devices unsuitable for these applications.
Another drawback with such devices is that they typically include a truck-mounted or large portable water pressurization system and/or a truck-mounted or large portable wastewater collection system. Accordingly, such systems are cumbersome and/or too complicated for the typical homeowner. As a result, there exists a need for simplified high pressure systems suitable for cleaning hard surface, including tiled and/or grouted surfaces.

Hard surface cleaners having cleaning heads with rotational assist, and associated systems, apparatuses and methods


A bidirectional optical fiber (12) amplifier suitable for use in a dual payout fiber-optic communication link (10) is disclosed herein. The inventive amplifier (12) is typically encasted in a shell or service loop, and is preferably connected between first and second optical fiber segments (18 and 20). The amplifier (12) includes a pump laser (102) for generating optical energy of a first wavelength. A wavelength selective optical coupler (82), in optical communication with the first fiber segment (18) and the pump laser (102), combines optical energy propagating through the first fiber segment (18) with the optical output of the pump laser (102). The amplifier (12) of the present invention further includes a doped optical fiber (114), optically connected between the wavelength selective optical coupler (82) and the second optical fiber segment (20), for amplifying optical energy within a predetermined wavelength spectrum passing therethrough. The inventive amplifier (12) may be advantageously employed within certain fiber-optic communication links in order to enhance optical signal strength.

1. Field of the Invention:
This invention relates to fiber-optic communication systems. More specifically, this invention relates to optical amplification arrangements for fiber-optic communication systems.
While the present invention is described herein with reference to a particular embodiment, it is understood that the invention is not limited thereto. Those having ordinary skill in the art and access to the teachings provided herein will recognize additional embodiments within the scope thereof.
2. Description of the Related Art:
In certain remote-guidance systems, communication with a guided vehicle is facilitated by an optical fiber link between the vehicle with a control station. The optical fiber is typically wound around a bobbin, or secured by other means capable of dispensing the fiber as the vehicle travels downrange. An optical carrier of a first wavelength is used to transport commands from the control station to the vehicle, while data from the vehicle is impressed upon an optical carrier of a second wavelength and carried by the fiber to the control station. Hence, bidirectional communication is effectuated in conventional fiber-optic systems by using optical energy at a pair of wavelengths to carry information in opposing directions.
Unfortunately, signal loss induced by the connecting fiber is typically minimized only at relatively long optical wavelengths. Since the optical carriers propagating in opposite directions along the link must generally be separated by a sufficient wavelength spacing to prevent inter-channel interference (cross-talk), it is generally not possible to choose the wavelength of both carriers to be within the relatively narrow wavelength spectrum of minimal signal loss. Accordingly, the signal transmission range of conventional dual-wavelength bidirectional optical fiber communication links is less than would be possible for a fiber link operative within a wavelength spectrum of minimal signal loss.
Fiber-induced signal loss generally necessitates intermediate amplification in long range systems. However, in conventional dual wavelength systems complex and expensive optical repeaters are used for signal amplification. Optical repeaters operate by first converting the signals carried by the light energy back to the electrical domain. Next, these extricated electrical signals are superimposed upon a separately generated optical carrier. In addition, optical repeaters complicate system design as these circuits often need to be included at multiple locations in very long-range fiber-optic links.
It follows that a need in the art exists for an optical amplifier suitable for use in a long-range fiber-optic communication link, wherein the amplifier is operative over an optical spectrum of minimal fiber-induced signal loss.

Amplifier for optical fiber communication link


The present invention provides a technique for ordering responses received over a split transaction bus, such as a HyperTransport bus (HPT). When multiple non-posted requests are sequentially issued over the split transaction bus, control logic is used to assign each request an identifying (ID) number, e.g. up to a maximum number of outstanding requests. Similarly, each response received over the split transaction bus is assigned the same ID number as its corresponding request. Accordingly, a “response memory” comprises a unique memory block for every possible ID number, and the control logic directs a received response to its corresponding memory block. The responses are extracted from blocks of response memory in accordance with a predetermined set of ordering rules. For example, the responses may be accessed in the same order the corresponding non-posted requests were issued.

A computer network is a geographically distributed collection of interconnected subnetworks for transporting data between nodes, such as computers. A local area network (LAN) is an example of such a subnetwork; a plurality of LANs may be further interconnected by an intermediate network node, such as a router or switch, to extend the effective "size" of the computer network and increase the number of communicating nodes. The nodes typically communicate by exchanging discrete frames or packets of data according to predefined protocols. In this context, a protocol consists of a set of rules defining how the nodes interact with each other.
Each node typically comprises a number of basic systems including a processor, a main memory and an input/output (I/O) system. Data is transferred between the main memory, processor and I/O system over a system bus, while data transactions within the I/O system occur over an external bus, such as an I/O bus. Each bus typically consists of either address, data and control lines, with the control lines carrying control signals specifying the direction and type of transfer, or a pair of unidirectional communication lines for passing bus packets containing address, data and control information, such as in the case of a HyperTransport (HPT) bus. For example, the processor (i.e., a source) may issue a read transaction to request the transfer of data from an addressed location on an I/O device (i.e., a target) coupled to the I/O bus and over the system bus to the processor. The processor then processes the retrieved data in accordance with instructions that may have been obtained from main memory. The processor may thereafter issue a write transaction requesting that the results be stored in, e.g., an addressed location in the main memory.
Some buses operate in an "atomic" manner such that the source is granted exclusive access (i.e., control) to the bus until the transaction is complete. However, an atomic bus may potentially waste bus cycles, particularly when waiting for data in response to, e.g., a read request. In a split transaction bus, on the other hand, the source relinquishes control over the bus once the request is sent and an independent response to the request is subsequently returned to the source. Here, the target acquires control of the bus to return the response to the source. The split transaction bus thus essentially enables a transaction to be divided into at least two transfers: the request and the response.
Devices coupled to the split transaction bus typically include common sets of resources (such as buffers or queues) used to store request and response transfers sent over the bus. It is possible that some of the resources may be consumed by these transfers, thereby causing the bus to stall waiting on the resources to no longer be in use (freed). This stall, in turn, may result in a plurality of transferred requests concurrently awaiting responses (i.e., "outstanding") over the split transaction bus. These resources allow several requests to be concurrently awaiting responses over the split transaction bus. Responses to pending requests are additionally limited by the inherent latency of accessing memory locations over the bus.
When a plurality of requests are outstanding, memory access delays may result in responses arriving "out of order." That is, the responses may be received in a different order than their corresponding requests. For example, assume a source sends a non-posted request R0 to a first target device over a split transaction bus, e.g. a HPT bus. Subsequently, the source sends a non-posted request R1 over the bus to a second target device. As used herein, a non-posted request is a request requiring a response, such as a request to read data. In the situation where the second target device has a lower memory latency than the first target device (i.e., due to memory access optimizations or a faster memory controller), the response to request R1 is received before the response to request R0. Similarly, other consecutive requests may arrive "out of order" depending on how quickly their respective target devices process the requests.
Often, the order responses are received from a split transaction bus is important for reconstructing a packet of information, e.g. a network data packet. Typically, a sequence of responses is sequentially concatenated to form a discrete packet of data/information. The data packet may be used within a predefined network protocol, such as the TCP/IP protocol. Unordered responses may therefore inhibit proper construction of a received information packet.
Furthermore, the order responses are received from a split transaction bus can be important when the response data is retransmitted over another communication channel. These responses may comprise data that will be retransmitted over a general communication link having predefined ordering rules. Thus, responses received from the split transaction bus may have to be reordered to comply with the ordering protocol of the general communication link.
Often, target devices are responsible for returning responses in a predefined order over a split transaction bus. These target devices typically require dedicated resources, such as circuitry and memory structures, to implement an ordering protocol. However, resources configured to implement an ordering scheme in a target device may limit the device's "read" bandwidth, i.e. how quickly data is retrieved from memory. For example, if a first-in, first-out (FIFO) queue in a target device maintains the order of requests received from a split transaction bus, then a delay processing a first request in the queue affects the processing times for subsequent requests in the queue. In those situations where requesting sources are configured to reorder responses received from a split transaction bus, each source must consume resources and bandwidth to implement the ordering protocol.


The invention features a thin light transmissive layer of the ternary semiconductor indium aluminum arsenide (InAlAs) as a front surface passivation or "window" layer for p-on-n InP solar cells. The window layers of the invention effectively reduce front surface recombination of the object semiconductors thereby increasing the efficiency of the cells.

The invention relates to indium phosphide (InP) semiconductor devices, and more particularly to a method of improving the efficiency of InP solar cells and other photo-receivers, and the improved cells produced thereby. InP solar cells have excellent radiation tolerance and the potential for extremely high efficiency. However, to date InP solar cells have not equalled the efficiency of other materials such as GaAs because of its propensity for high recombination of minority carriers at the front surface of the cell. The purpose of this invention is to increase the efficiency of InP solar cells by reducing the recombination of minority carriers at the front surface.
In InP, one of the most significant causes of poor efficiency is the recombination of electrons and holes at the front surface of the device, a process called surface recombination. Experimentally measured values of surface recombination velocity (SRV) on InP solar cells are extremely high. The surface recombination velocity calculated from measured values of the short wavelength quantum efficiency and current-voltage characteristics of the best existing InP solar cells is in the range of 5.times.10.sup.6 to 10.sup.7 cm/s, which is unfavorably high. Once recombined at the surface, the carriers are lost and cannot contribute to either the output voltage or the output current of the cell.
High front surface recombination in InP cells is typically addressed by using n-on-p cell configurations, where n-type InP is used as the front surface or "emitter" layer. High doping (n.sup.+) levels in the n-InP and extremely shallow emitter layers contribute to minimize surface losses in the emitter. However, the best n-on-p type InP cells have 19% conversion efficiency measured at Air Mass Zero (AM0), and the best p-on-n InP cells today have efficiencies of 15% AM0. Thus, with the present technology, p-on-n cells are not as efficient as n-on-p cells, and neither is as efficient as GaAs cells, which have been manufactured with over 22% efficiency.
In front surface recombination velocity could be reduced, theoretical studies by the inventors indicate that p-on-n cells would have better open circuit voltage and higher efficiency than n-on-p cells. The heavy doping of the emitter required in n-on-p cells to minimize the adverse effects of high surface recombination leads to efficiency loss. The shallow emitter required is difficult to fabricate and has high resistance, leading to further losses.
Some InP solar cells have been made using as the active material InP which has been deposited or "grown" on a substrate of a different crystalline material. This is advantageous because a substrate may be used which is stronger, lighter or lower in cost than single crystal wafers of InP, while retaining all of the features of an InP solar cell. Two crystalline substrates of particular interest are silicon and germanium, which are available in wafer form. A difficulty in this approach, however, is that in the process of growing the InP, the Si or Ge will tend to diffuse from the substrate into the InP layer being grown, doping the InP to n-type. The p-on-n type solar cell is preferable for this application because it can make use of the n-type doping in the base. Thus, reduction of surface recombination in p-on-n type InP is particularly important for these cell designs.
InP solar cells can also be used as one element in a tandem solar cell, where it is used in conjunction with other solar cell materials. For example, an InP solar cell may be used on top of an InGaAsP solar cell, so that the light which penetrates through the InP can be usefully absorbed by the InGaAsP.
Finally, while the devices discussed in detail are solar cells, other electronic devices designed to absorb light, such as photodetectors, photodiodes, phototransistors, laser power receivers, thermophotovoltaic cells and the like could also be fabricated out of InP and would likewise benefit from reduced surface recombination at the light absorbing surface. Hence, there is a need for alternative methods of minimizing the effects of high surface recombination velocities in InP that do not have the disadvantages associated with current methods. By increasing the efficiency of InP devices, and in particular p-on-n InP, in this way, they will become more suitable for space power applications where their excellent radiation tolerance can be exploited.

The United States of America as represented by the Administrator of the National Aeronautics and Space Administration


A capsule for containing at least one reactant and a supercritical fluid in a substantially air-free environment under high pressure, high temperature processing conditions. The capsule includes a closed end, at least one wall adjoining the closed end and extending from the closed end; and a sealed end adjoining the at least one wall opposite the closed end. The at least one wall, closed end, and sealed end define a chamber therein for containing the reactant and a solvent that becomes a supercritical fluid at high temperatures and high pressures. The capsule is formed from a deformable material and is fluid impermeable and chemically inert with respect to the reactant and the supercritical fluid under processing conditions, which are generally above 5 kbar and 550° C. and, preferably, at pressures between 5 kbar and 80 kbar and temperatures between 550° C. and about 1500° C. The invention also includes methods of filling the capsule with the solvent and sealing the capsule, as well as an apparatus for sealing the capsule.

The invention relates generally to a capsule to be used with pressure vessels. More particularly, the invention relates to a capsule used in conjunction with a high-pressure vessel for processing at least one material in a supercritical fluid.
Supercritical fluids (also referred to hereinafter as "SCF") may be used to process a wide variety of materials. Examples of SCF applications include extractions in supercritical carbon dioxide, the growth of quartz crystals in supercritical water, and the synthesis of a variety of nitrides in supercritical ammonia.
Processes that employ supercritical fluids are generally performed at high pressure and high temperature (also referred hereinafter as "HPHT") within a pressure vessel. Most conventional pressure vessels not only provide a source of mechanical support for the pressure applied to reactant materials and SCF, but also serve as a container for the supercritical fluid and material being processed. The processing limitations for such pressure vessels are typically limited to a maximum temperature in the range between about 550° C. and 750° C. and a maximum pressure in the range between about 2 kilobar (also referred hereinafter as "kbar") and 5 kbar.
Processing material with supercritical fluids requires a container or capsule that is both chemically inert and impermeable to the solvent and any gases that might be generated by the process. In one approach, the material to be processed, along with a solid or liquid that forms a supercritical fluid at elevated temperatures, is introduced into a capsule. The capsule is then sealed in air, placed in a high pressure apparatus, and heated. The solid (or liquid) decomposes upon heating to provide a supercritical fluid. When such a solid or liquid is used as the SCF source, however, decomposition products other than the supercritical fluid that remain in the reaction mixture may contaminate the reaction mixture. Additional contamination may also result from air introduced during filling of the capsule.
In one method, air may be excluded from a capsule by placing the material to be processed into a fused silica tube having a closed end, evacuating the tube through a vacuum manifold, and condensing a solvent into the tube. The tube is then sealed, usually by welding, without exposing the contents of the capsule to air. Once the capsule is sealed, however, the material inside the tube cannot be processed at internal pressures greater than about 6 bar and temperatures higher than about 300° C., as the internal pressure generated by vaporization of the solvent will cause the sealed capsule to burst when heated to higher temperatures. An external pressure greater than or equal to the internal pressure can be provided by placing the capsule inside a pressure vessel and filling the space between the capsule and the pressure vessel with a solvent. However, as noted above, such pressure vessels are typically limited to a maximum temperature in the range between about 550° C. and 750° C. and a maximum pressure in the range between about 2 and 5 kbar.
If the pressure, temperature, chemical-inertness, size, sealing, and cost limitations of currently available capsules could be extended, supercritical fluids could be used to process a wider range of materials. Therefore, what is needed is an improved capsule or container for processing of materials with supercritical fluids in an air-free environment. What is also needed is a capsule that can be utilized with a solvent that is gaseous at room temperature. What is further needed is a chemically inert capsule that may be used in conjunction with a pressure vessel that is capable of generating pressures greater than about 5 kbar and temperatures between about 550° C. and about 1500° C. What is further needed is a chemically inert capsule that can cost-effectively process materials on a larger scale.

High temperature high pressure capsule for processing materials in supercritical fluids


An inertial decoupler and suppressor assembly, associated components, and associated methods. The inertial decoupler is adjustable to change a preload of a spring biasing a piston toward an at-rest position and/or to change a permitted travel distance of the piston away from the at-rest position. The inertial decoupler can be removable from the suppressor and usable with other suppressors, or can be integrated with a dedicated suppressor.

A suppressor mounted on a barrel of a pistol can cause the pistol to not cycle properly after being fired. The mass of the suppressor can increase the effective mass of the barrel such that the barrel does not move properly to cycle the pistol. To overcome this side effect, suppressors mounted on pistols often include an inertial decoupling device called a Nielsen device, booster, or linear inertial decoupler or damper (LID). Such devices temporarily "decouple" the mass of the suppressor from the barrel when the pistol is fired. Accordingly, the pistol is permitted to cycle properly notwithstanding the mass of the suppressor mounted on the barrel.

Inertial decoupler for firearm sound suppressor


A radiation emitter component, in particular an infrared emitter component with a conventional light-emitting diode housing, includes two electrode connections, one of which has a well-shaped reflector. The housing has an optically transparent, electrically non-conducting encapsulation material. A semiconductor laser chip is fastened in a well-shaped reflector of the light-emitting diode housing. The semiconductor laser chip has a quantum well structure, in particular with a strained layer structure, for example MOVPE epitaxial layers with a layer sequence GaAlAs-InGaAs-GaAlAs. A diffusor material can be inserted into the optically transparent, electrically non-conducting material of the light-emitting diode housing. The diffusor material is constructed or inserted with regard to type and concentration in such a way that in connection with the semiconductor laser chip encapsulated in the light-emitting diode housing, a radiation characteristic curve or an increase of an effective emission surface is produced that is comparable to that of a conventional infrared light-emitting diode.

Field of the Invention
The invention relates to a radiation emitter component including a semiconductor laser chip having a semiconductor substrate, an active laser layer constructed on the semiconductor substrate and having a quantum well structure, and at least one first and one second contact layer each connected to the active laser layer in an electrically conducting manner. The invention relates in particular to an infrared emitter component.
In the prior art, conventional light-emitting diodes on one hand, and GaAs-infrared light-emitting diodes, for example, on the other hand, are known as optoelectronic luminescence components. Due to their limited optical properties, the mass-produced conventional light-emitting diodes cannot as a rule be used where higher power, shorter switching times, and low wavelength band widths are required. In fact, an attempt has been made to improve such infrared light-emitting diodes, for example by adding GaAs-GaAlAs material with so-called double heterotransitions in order to increase power and data rates and to improve them by adding a transparent substrate to increase power further. However, despite those measures, the use of that kind of light-emitting diode particularly in the computer and computer peripheral field has only been possible to a greatly limited degree up till now. That application field has previously been limited almost exclusively to optoelectronic laser components. Due to a high degree of mechanical sensitivity of semiconductor laser chips, until now they have been mounted in the usual way in the known unencapsulated metal housings, e.g. TO-18 housings or SMD housings (Surface-Mounted Device housings). An example of a metal housing of that kind is shown in German Published, Non-Prosecuted Patent Application DE 37 32 075 A1, corresponding to U.S. Pat. No. 4,940,855.
Semiconductor laser chips with a semiconductor substrate and an active laser layer that is constructed on the semiconductor substrate and has a quantum well structure are known, for example, from the following publications:
H. Lang et al.: GaAs/AlGaAs Quantum Well Laser for High-Speed Applications, IEE PROCEEDINGS J. OPTOELECTRONICS, Vol. 138, No. 2, Apr. 1, 1991, pp. 117-121;
C. A. Wang et al.: High Power, High Temperature InGaAs-AlGaAs Strained-Layer Quantum-Well Diode Lasers, Electronics Letters, Vol. 30, No. 8, Apr. 14, 1994, pp. 646-648;
W. T, Tsang et al.: Low-Threshold InGaAs Strained-Layer Quantum Well Lasers (.lambda.=0.98 .mu.m) with GalnP Cladding Layers Prepared by Chemical Beam Epitaxy, Applied Physics Letters, Vol. 61, No. 7, Aug. 17, 1992, pp. 755-757;
D. P. Bour et al.: Tensile-Strained AlGaAsP- and InGaAsP-(AlGa).sub.0.5 In.sub.0.5 P Quantum Well Laser Diodes for TM-Mode Emission in the Wavelength Range 650<.lambda.<850 nm, IEEE Photonics Technology Letters, Vol. 6, No. 11, November, 1994, pp. 1283-1285;
Patent Abstracts of Japan, Vol. 002, No. 027 (E-016), Feb. 21, 1978, JP-A-52 149 081;
F. Bugge et al.: Effect of Growth Interruption on Performance of AlGaAs/InGaAs/GaAs Quantum Well Lasers, Journal of Crystal Growth, Vol. 145, 1994, pp. 907-910; and
S. Karakida et al.: Metalorganic Chemical Vapor Deposition Growth of High-Quality and Highly Uniform Strained InGaAs Quantum Wells in a High-Speed Rotating-Disk Reactor, Journal of Crystal Growth, Vol. 145, 1994, pp. 662-667.


A semiconductor light emitting device comprises: a substrate; a semiconductor stacked structure; a first electrode; a second electrode; and a reflective film. The substrate has a top face and a rear face electrode forming portion opposed thereto, and is translucent to light in a first wavelength band. The rear face electrode forming portion is surrounded by a rough surface. The semiconductor stacked structure is provided on the top face of the substrate and includes an active layer that emits light in the first wavelength band. The first electrode is provided on the semiconductor stacked structure, and the second electrode is provided on the rear face electrode forming portion. The reflective film is coated on at least a portion of the rough surface.

This invention relates to a semiconductor light emitting device and a semiconductor light emitting apparatus, and more particularly to a semiconductor light emitting device and a semiconductor light emitting apparatus having improved extraction efficiency for light emitted from the active layer.
Semiconductor light emitting devices such as LEDs (light emitting diodes) and LDs (laser diodes) provide various emission wavelengths, high emission efficiency, and long lifetime while being compact in size. For this reason, they are widely used for display, lighting, communication, sensor, and other devices.
In such a semiconductor light emitting device, a semiconductor multilayer film including an n-type cladding layer, active layer, p-type cladding layer, and the like is formed on a substrate of GaAs or sapphire by direct epitaxial growth, or by lamination with a heterogeneous substrate. Electrodes are further formed on the n-type and p-type layers, respectively (e.g., Japanese Laid-Open Patent Applications 2002-353502 and 2001-217467).
However, this type of semiconductor light emitting device does not have sufficiently high extraction efficiency for light emitted from the active layer.
More specifically, the light emitted downward from the active layer is incident on the electrode provided under the substrate. However, the substrate has an alloyed region formed with the electrode material near the interface with the electrode. This causes a problem that the light emitted from the active layer is prone to absorption, which leads to a certain loss inside the chip.
In addition, the light reflected from the lower electrode is attenuated by optical absorption in passing through the active layer. This causes a problem that the reflected light cannot be fully exploited.
There is another problem that total reflection is likely to occur at the side face and the like of the chip. More specifically, the above-described LED is typically processed into a rectangular parallelepiped shape having six smooth faces by cleavage and dicing, and covered with mold resin or the like. However, due to the large difference between a high refractive index of the semiconductor crystal (about 3.5) and a low refractive index of the mold resin (about 1.5), total reflection is likely to occur at the interface therebetween. This decreases the probability that the light emitted inside the chip is extracted outside the chip.
An approach to improving the decrease of light extraction efficiency is to roughen the surface by wet etching or the like to form asperities (e.g., Japanese Laid-Open Patent Application 2001-217467). However, surface roughening is not effective for extracting light emitted toward the bottom face inside the chip mounted on a packaging member.

Semiconductor light emitting device and semiconductor light emitting apparatus


One embodiment disclosed relates to a method of providing dynamic temperature-adjusted power redundancy for a system. Tracking is performed of the number of power supply units, n, that are presently in an up state. The temperature in which the power supply units are operating is measured, and a temperature-adjusted number of power supply units, N, which are presently needed to supply power to the system, is dynamically determined.

1. Field of the Invention
The present invention relates generally to power supplies for electronics and computers.
2. Description of the Background Art
Supplying power with back-up or redundancy to computer systems or servers is desirable or required in certain applications. For example, it is becoming increasingly more important to provide mechanisms that minimize unscheduled "down time" in data centers. The term "high availability" (HA) computing is often used to refer to computer systems that include these mechanisms.
HA mechanisms are provided at many levels. For example, a data center may have redundant computer systems so that if one system fails, the workload can be seamlessly shifted to another system. In addition, data may be stored in a disk array subsystem that allows any single disk drive to fail without affecting the ability of the disk array subsystem to continue operating.
One of the most important aspects of HA computing is ensuring that computer circuits receive an uninterrupted supply of DC power. Typically, a loss of DC power is caused by a loss of AC power to the AC-to-DC power supplies, or a failure of an AC-to-DC power supply. Uninterruptible AC power supplies address the problem of AC power loss by providing a constant supply of AC power to AC-to-DC power supplies. Typically, uninterruptible power supplies are implemented using rechargeable batteries, and in some cases, generators.
Redundant AC-to-DC power supplies address the problem of AC-to-DC power supply failure. In the prior art, redundant power supplies have been deployed on a "per system" basis. Typically, one redundant power supply is provided for each system, which is known in the art as "N+1" redundancy.
Computer systems also use DC-DC conversion since in many cases it is more efficient to provide AC-DC conversion to a single high DC voltage (typically 48V), then bus this voltage to second stage down-converters. In many cases, these DC-DC conversion devices are also required to be redundant.

Method for determining number of dynamically temperature-adjusted power supply units needed to supply power according to measure operating temperature of power supply units

Hewlett-Packard Development Company, L.P.


A frequency multiplier for controlling a pulse width maintains a desired pulse width irrespective of a semiconductor fabrication process variation. The multiplier includes a delay unit for delaying an input signal and an exclusive OR-gate for exclusively ORing the delayed signal from the delay unit and the input signal. The multiplier further includes inverters that sequentially invert the signal from the exclusive OR-gate and a low-pass filter that filters the signal from the exclusive OR-gate. A high electric potential comparator and low electric potential comparator are for comparing the signal from the low-pass filter with first and second voltage limits to output first and second switch control signals to the delay unit, respectively.

1. Field of the Invention
The present invention relates to a frequency multiplier for controlling a pulse width, and in particular, to a frequency multiplier for controlling a pulse width that maintains a prescribed pulse width.
2. Background of the Related Art
FIG. 1 illustrates a related art frequency multiplier. Delay units D1, . . . , DN delay respectively an input signal VI at different delay ratios, and a multiplexor 1 selectively outputs a corresponding one of delay speeds TD 1, . . ., TD N of the delay units D1, . . . , DN. An exclusive OR-gate 2 exclusively ORs an output signal from the multiplexor 1 and the input signal VI.
The delay units D ,. . ., DN having different delay ratios delay the input signal VI to output delayed signals having the delay speeds TD 1,. . ., TD N to the multiplexor 1. The multiplexor 1 selects one of the delay speeds TD1, . . ., TD N of the delay units D1, . . . DN and outputs the delay speed. The OR-gate 2 exclusively ORs the output signal from the multiplexor 1 and the input signal VI.
Therefore, an output signal VO from the exclusive OR-gate 2 has a different pulse width based on the delay ratios of the delay units D1, . . . , DN. However, the related art frequency multiplier has various disadvantages. The related art frequency multiplier uses a plurality of delay devices. In addition, an accurate delay ratio is required for the delay units to maintain the pulse width having a predetermined range. If the delay ratio of the delay device varies based on semiconductor fabrication process variations, it is not possible to maintain the pulse width within the predetermined range.

Frequency multiplier for controlling pulse width within a prescribed range