The present invention provides a process which utilizes biodiesel and other high boiling esters containing short alkyl groups to produce liquid fuels from waste material. The waste material is added to a solvent having a predetermined cycle starting solvent volume. An energy source is introduced into the solvent for a predetermined time at a predetermined temperature and pressure to form a non-grindable product. The energy source is removed and the product is cooled to a predetermined temperature to produce the fuel. The invention also encompasses the fuel formed by the process described.

The accumulation of waste materials has become a significant societal problem. Such waste materials include, for example, non-organic matter, organic matter, and polymeric materials having extremely low or zero degradation rates. For example, the number of tires produced and disposed of in the United States is estimated to be about 300 million annually. Additionally, fluff produced by, for example, recycled motor vehicles and appliances is estimated to be 500 pounds of fluff for each ton of recovered steel.
The uses for waste tires are rather limited. While they have been added to asphalt, burned in kilns, used as shock absorbers in playgrounds, and used as absorbers of oil spills, the vast majority of waste tires remain as a problematic environmental and health concern.
Natural rubber is a polymer deriving from isoprene (2-methyl-1,3-butadiene). The molecular weight of the natural rubber varies significantly and is between 104 and 106. The Merck Index defines rubber as cis-1,4-polyisoprene with a molecular weight varying from 100,000 to one million. Both natural and synthetic rubber is usually cross-linked with sulfur, peroxides or bisphenol. The process, called vulcanization, produces a three-dimensional lattice. It improves properties of the product which becomes much stronger, more temperature sensitive, more elastic and non-sticky.
While natural rubber is soluble in chloroform, absolute ether, many fixed and volatile oils, petroleum ether, carbon disulfide, and oil of turpentine, the cross-linked product is much less so. The synthetic varieties can derive from one or more of the following: 1,3-butadiene, chloroprene (2-chloro-1,3-butadiene), and similar monomers. The relevant copolymers often derive from styrene. Styrene-butadiene-rubber, or SBR, is the largest synthetic component of tires.
An estimated 60% of all manufactured rubber is used in tires. A typical passenger tire consists of natural rubber (14%), synthetic rubber (27%), carbon black (28%), steel (14-15%), and additives (fabric, fillers, accelerators, antiozonants, etc.) (16-17%). Its average waste weight is 20 lbs. A typical waste truck tire weights 100 lbs and contains reverse proportions of synthetic and natural rubber as compared with a car tire.
Waste tires are not biodegradable, thereby creating both an environmental and health problem. They exacerbate the spread of mosquito-borne diseases in that they provide an insect breeding ground. Additionally, whole tires are difficult to store in landfills in that they are bulky and cause damage to the landfill cap or seal, as they tend to "float" their way to the top of the fill. In an attempt to prevent this migration, many landfills require that scrap tires be shredded, a process which is energy intensive and wasteful if it does not produce any useful product. Due to the cost associated with proper disposal, many tires are dumped illegally.
In response to these problems, there are a number of known methodologies utilized to recycle used rubbers, all of which have significant limitations. Tires have been both combusted to produce energy and pyrolized to produce fuels. Pyrolysis is generally defined as thermal degradation at temperatures as high as 900 degree C. in an inert atmosphere and has been favored because lower temperature attempts to use tires as a source of energy have heretofore not been economic.
The breakage of rubber's covalent bonds requires that relatively large quantities of energy be delivered to the waste rubber material. Pyrolysis usually takes place at temperatures above 530 degrees C. All of these high-energy techniques use "dry" processing, in that the two reaction products are gas and solids. Some of the gas exhibits molecular weight high enough to condense with cooling water, useful as a valuable liquid fuel, but most is lower value gas and solid fuel.
Potentially economic and useful methodologies that have been attempted to introduce energy into rubber to break the covalent bonds are direct heating, ultra-sound, and microwave energy.
A single car waste tire weighing about 20 pounds has about the same heating value of coke, approximately 15,000 BTU's per pound, or approximately 258,000 BTU's per tire. Therefore, if economical, environmentally sound processes can be formulated to convert waste tires, fluff and other polymeric materials into a fuel source, much of the aforementioned problems can be obliviated. Accordingly, there is still a continuing need for improved methods of transforming tires, fluff and other polymeric materials into fuel. The present invention fulfills this need and further provides related advantages.


This specification discloses a method of hydraulic fracturing a subterranean formation wherein two horizontally spaced-apart wells are provided and completed to communicate with the formation. Hydraulic fluid pressure is sequentially applied to create and propagate vertical fractures into the formation and to create a vertical fracture that communicates both wells.

This invention is concerned with an enhanced method of sequentially hydraulic fracturing a subsurface formation. This invention is also concerned with a method of producing hydrocarbons from a hydrocarbon-bearing formation that has been fractured by using an enhanced sequential hydraulic fracturing method.
Hydraulic fracturing techniques have been widely used for stimulating wells penetrating subsurface or subterranean hydrocarbon-bearing formations by creating fractures which extend from the wells into the formation. These techniques normally involve injecting a fracturing fluid down a well and into contact with the subterranean formation to be fractured. A sufficiently high pressure is applied to the fracturing fluid to initiate a fracture in the formation and the fracturing fluid is injected down the well at a sufficiently high rate to propagate the fracture thereinto. Propping materials are normally entrained in the fracturing fluid and are deposited in the fracture to maintain the fracture open.
In U.S. Pat. No. 4,067,389 there is described a technique of hydraulically fracturing a subterranean formation wherein there is used a fracturing fluid comprised of an aqueous solution of an interaction product of a polysaccharide and a galactomannan.
In U.S. Pat. No. 3,547,198 there is described a method of forming two vertically disposed fractures communicating with a well equipped with a casing and which well penetrates a subterranean earth formation having a known preferred fracture orientation.
In U.S. Pat. No. 4,724,905 there is described a process for sequentially hydraulic fracturing a hydrocarbon-bearing formation penetrated by two closely spaced wells. In sequential hydraulic fracturing, the direction that a hydraulic fracture will propagate is controlled by altering the local in-situ stress distribution in the vicinity of a first wellbore. By this method, a hydraulic fracturing operation is conducted at the first wellbore wherein hydraulic pressure is applied to the formation sufficient to cause a hydraulic fracture to form perpendicular to the least principal in-situ stress.
While maintaining pressure in this first hydraulic fracture, a second hydraulic fracture is initiated in a second wellbore. This second hydraulic fracture, due to the alteration of the local in-situ stresses by the first hydraulic fracture, will initiate at an angle, possibly perpendicular, to the first hydraulic fracture.

Two well hydrocarbon producing method using multiple fractures


In an apparatus for actively controlling a steer angle of front wheels of a vehicle, a steering angle of a steering wheel is detected and then an active control amount for actively controlling the steer angle of the front wheels including a proportional term and a differential term is calculated. After only the differential term has been delayed, the steer angle of the front wheels is controlled in accordance with the active control amount. Since the differential component in the active control amount has been delayed, the steer angle of the front wheels is changed gradually, so that the variation in the steering force is suppressed. Therefore, the maneuverability and operating properties of the vehicle can be improved.

Field of the Invention and Related Art Statement
The present invention relates to an apparatus for controlling a steer angle of front wheels of a vehicle, and more particularly to an apparatus for effecting an active control in which a steer angle of the front wheels is increased actively in accordance with a steering wheel angle.
There has been proposed an apparatus for actively controlling a steer angle of front wheels of a vehicle, in which, in addition to a usual control of the front wheels in proportion to a steering wheel angle, the steer angle of the front wheels is auxiliarily controlled in an active manner. There has been also proposed an apparatus for auxiliarily controlling both the front wheels and the rear wheels in an active manner. The latter apparatus is utilized in a so-called four wheel steering (4WS) vehicle. For instance, in Japanese Patent Publication Kokai Sho No. 60-161,266, the above mentioned steer angle controlling apparatus is described.
In the known apparatus for actively controlling the steer angle of front wheels, an active control amount for auxiliarily or actively controlling the steer angle of the front wheels is calculated in accordance with a steering wheel angle and a running velocity of the vehicle, and the steer angle of the front wheels is additionally increased by the thus calculated active control amount. This improves the stability and handling properties of the vehicle. For instance, when the steer angle of the front wheels is increased by the active control amount, upon a turn of the vehicle, a head-turning characteristic of the vehicle can be improved due to an increase in a yaw rate, i.e. an angular velocity of a yawing movement of a body of the vehicle.
In the known apparatus for controlling the steer angle of the front wheels in the active manner, the active control amount is derived by effecting calculations based on a steering wheel angle and an angular velocity of the steering wheel angle. Therefore, although the steering wheel angle is the same, a sideslip angle of the front wheels might be changed in dependence upon the angular velocity of the steering wheel angle. That is to say, the sideslip angle of the front wheels is increased in relation to a differential in time of the steering wheel angle. This results in that at an initiation of steering wheel operation by a driver, a force necessary for manipulating the steering wheel, i.e., a so-called steering force, is increased very abruptly, so that the steering force shows a large variation as illustrated by a curve A in FIG. 4C. Therefore, the known apparatuses for actively controlling the steer angle of the front wheels could not achieve optimum stability and maneuverability.

Apparatus for actively controlling steer angle of front wheels of vehicle


A wafer bonded composite structure is provided for matching a coefficient of thermal expansion of a first semiconductor chip to a coefficient of thermal expansion of a second semiconductor chip in order to provide a thermally matched hybridized semiconductor chip assembly. The wafer bonded composite structure includes a first semiconductor chip having a top and a bottom surface. The first semiconductor chip has a coefficient of thermal expansion which is less than the coefficient of thermal expansion of the second semiconductor chip. Preferably, the first semiconductor chip is an readout integrated circuit (ROIC) and the second semiconductor chip is an infrared detector chip. Further, the wafer bonded composite structure also includes a substrate wafer bonded to a bottom surface of the first semiconductor chip to form the wafer bonded composite structure itself. The wafer bonded substrate is preferably transparent to infrared radiation, so that the first semiconductor chip or ROIC of the resulting wafer bonded composite structure may be aligned with the second semiconductor chip or infrared detector chip before hybridization has taken place. Moreover, the composite structure has a coefficient of thermal expansion which at least substantially matches the coefficient of thermal expansion of the second semiconductor chip, thereby providing thermal matching between the first and second semiconductor chips.

1. Field of the Invention
This invention relates to matching the coefficient of thermal expansion (CTE) of one semiconductor chip to the CTE of another semiconductor chip and, more particularly to matching the CTE of an ROIC to the CTE of an infrared detector chip.
2. Prior Art
It is known in the art to hybridize different semiconductor chips together to form a hybrid array. One particular example would be hybridizing a readout integrated circuit chip (ROIC) and an infrared detector chip together to form a hybridized infrared detector array or sensor chip assembly (SCA). However, distinct semiconductor chips, such as the ROIC and the infrared detector chip, almost always have substantially different CTE's from one another, which leads to thermal mismatch problems.
One such thermal mismatch problem usually occurs when conducting the hybridization process of the ROIC to the infrared detector chip at elevated temperatures, e.g. 70-200° C. In particular, under elevated hybridization temperatures, if there is a substantial mismatch between the CTE of the ROIC and the infrared detector then a misalignment of the chips will occur. Namely, the indium bump connections between the ROIC and infrared detector chip will become misregistered or misaligned due to thermal mismatch. One result of the above thermal mismatch problems is a lessening of the number of options one has in performing hybridization of these chips.
Another major disadvantage with the prior art hybridized IR detector arrays and processes occurs when the hybridized infrared detector array is thermally cycled between room temperature and the typical 78 K (Kelvin) operating temperature. A problem arises because the ROIC chip (in most cases silicon) has a different CTE than the infrared chip (e.g. HgCdTe/CdZnTe) and a differential contraction will occur. One result is that the indium bump connections between the ROIC and the infrared chip can crack and open leading to circuit failure.
Other problems which typically result from thermal mismatch between the ROIC and the infrared detector chip manifest themselves as physical damage in the hybrid array and degraded performance. The physical damage may manifest itself as either local or global delamination of the hybrid, i.e., actual separation of the indium bumps between the detector and readout circuit, or cracking of the detector array. The performance degradation may manifest itself as a lack of uniformity between arrays, within an array, or as a general reduction in performance specifications.
Some prior art methods have attempted to rectify the above noted drawbacks using approaches discussed below. For example U.S. Pat. No. 5,672,545 to Trautt et al. ("the Trautt patent") is directed in relevant part to matching the CTE's between an ROIC and an infrared detector chip in order to provide a thermally matched flip-chip assembly. In order to accomplish this, a composite structure is designed to have a CTE which substantially matches the CTE of an infrared detector chip. The composite structure is comprised of the ROIC, a first compensation layer and a second compensation layer. The components of the composite structure are bonded together using epoxy adhesives.
In addition, U.S. Pat. No. 5,308,980 to Barton ("the Barton Patent") relates in relevant part to a hybrid detector array wherein the ROIC and the infrared detector chip are thermally matched. In particular, the Barton patent describes a hybrid infrared detector array, including a readout circuit chip hybridized to an infrared detector chip. The hybrid detector array further includes a readout circuit substrate having metal constituents which is bonded using epoxy adhesives to the bottom exposed surface of the ROIC to form a composite structure after hybridization has already taken place. The resulting composite structure is designed to have a CTE which is substantially the same as the infrared detector portion.
Further, U.S. Pat. No. 6,417,514 B1 to Eneim et al. relates in relevant part to a sensor/support system which includes a sensor assembly having a radiation detector, a readout circuit, and an interconnect joining the radiation detector to the readout circuit. The system further includes a support structure having a platform with a first side to which the sensor assembly is affixed and a second side oppositely disposed from the first side. A shim is affixed to the second side of the platform. The shim is designed to reduce the strain in the interconnect when the temperature of the sensor/support system is changed, as compared with the strain in the interconnect in the absence of the stabilization structure.
While some of the prior art noted above has addressed the issue of thermal mismatch between a readout circuit and an infrared detector chip, there is still a need in the art for an apparatus and method wherein the CTE of the ROIC is substantially matched to the infrared detector prior to hybridization. There is also a need in the art for a process of preparing a hybridized infrared detector array without the use of any adhesives, such as epoxy adhesives. The present invention fulfills these needs, and further provides related advantages.

Wafer bonded composite structure for thermally matching a readout circuit (ROIC) and an infrared detector chip both during and after hybridization


An improved dental strip which includes a dental rubber tube with a reduced silicon coating and wherein the talcum powder generally used between the inner surfaces of the rubber tube is replaced with by a flavoring compound, which is preferably in the form of a tooth powder, such as baking soda. Many flavoring compounds may be used, such as those which impart a fresh mint taste plus a medicament (e.g., fluoride), which is effective to inhibit the formation of dental caries. Baking soda, as eluded to above will neutralize the odor. A further improvement, and alternative embodiment of the present invention involves improving the appearance of the dental strip and making it easier to remove from a conventional dental strip pack.

1. Field of the Invention
The present invention relates, generally, to an improved dental strip is used to clean food particles from between one's teeth. More particularly, the present invention relates to an improved dental strip wherein the rubber floss utilized to make the dental strip is impregnated with a fluoride medicament and dentifrice. By the addition of flavoring to the dental strip, it can be expected that consumer acceptance of the improved dental strip of the present invention and, thus, the encouragement of routine flossing to aid therapeutic results will be improved.
Additionally, the inversion of the rubber floss strip, or tube, during manufacture of the same, improves utilization of the strip by providing the dental strip with a more rounded shape a conventional tube.
2. Description of the Prior Art
Heretofore, dental strips have been manufactured by die cutting a latex rubber tube. In the manufacturing of such tubes, a silicon coating is applied to the outer surface in order to prevent the same from becoming tacky. The inner surface of the conventional dental tube, or strip, is coated with talcum powder in order to prevent the dental tube from sticking together.
The latex rubber with the silicon coating and talcum powder, unfortunately, leaves a foul taste and odor in one's mouth. As a result, notwithstanding the benefits from flossing on a regular basis, users are inclined to avoid flossing as much as might be beneficial.
This type of dental strip is disclosed and claimed in my earlier patent, U.S. Pat. No. 3,860,013, issued Jan. 14th, 1975.
As will be explained in greater detail hereinafter, the present invention overcomes the prior art deficiencies encountered when the tube of the dental strip becomes stuck together. Additionally, the present invention avoids the deficiencies encountered when users of the dental strips, presently known to the art, seek to avoid proper and regular usage of such strips due to the foul taste and odor.
Finally, the present invention seeks to overcome the deficiencies inherent in the prior art in a manner which is economically competitive for conventional dental strips.


The present invention relates to a cooling system for a cryostat incorporating a pulse tube refrigerator 8. The cryostat usually consists of several interior cylindrical or oval-shaped vessels for storing liquids. The cryostat for MRI/NMR applications and related fields usually comprises an outer vacuum case, a nitrogen can or a radiation shield instead, and a further radiation shield and the helium vessel housing 4 the superconducting magnet 2. The magnet usually is made of NbTi, Nb3Sn, or some HTC conductor or a combination of both.

The present invention relates to the use of coaxial pulse tube refrigerators in MRI or NMR systems, particularly in the neck tube of such systems.
Coaxial pulse tube refrigerators are described in a paper entitled xe2x80x9cDevelopment of a Practical Pulse Tube Refrigerator: Coaxial design and the influence of viscosityxe2x80x99 by R. N. Richardson in Cryogenics 1988 Vol. 28 August, pages 516-520. A pulse tube refrigerator (PTR) comprises two tubes, a pulse tube and a regenerator tube, in which an oscillating pressure-wave of gas produces the cooling effect. The paper states that the concentric pulse tube design provides a convenient, compact configuration for achieving high heat pumping rates. Instead of placing the regenerator concentrically around the pulse tube which is the preferred configuration, the pulse tube occupies the annular space and surrounds the regenerator at the center.
One object of the present invention is to incorporate a coaxial pulse tube refrigerator into the neck portion of an MRI and NMR system.
According to the present invention there is provided an MRI or NMR system comprising a magnet assembly immersed in a cooling liquid contained within a vessel, and having an orifice in the form of a neck-tube. The neck-tube is adapted to house a pulse tube refrigerator which is in the form of an annulus or a section of an annulus.
The pulse tube refrigerator may have an enhanced surface structure which is either a natural or an artificial structure.
The pulse tube refrigerator has its regenerator tube in the form of an annulus which is concentric and coaxial and in contact with either the inside or outside of its pulse tube.
The regenerator tube or pulse tube may also act as a suspension element.

Abstract: The present invention uses a pulse tube refrigerator 8, the so-called pulse tube cooler, which essentially comprises an empty tube and a further tube housing the regenerator material for the cooler, which is inserted into any opening of a cryostat. The opening is defined as e.g. the neck-tube 6 or any other location required for accessing the cryostat, e.g. for the transfer of liquids, for energising the magnet, an opening acting as a pressure relief or most simply as a drainage outlet in case of storage vessel for cryogenic fluids.


A pattern matching method for matching between a first symbol sequence and a second symbol sequence which is shorter than the first symbol sequence is provided. The method includes the steps of performing DP matching between the first and second symbol sequences to create a matrix of the DP matching transition, detecting the maximum length of lengths of consecutive correct answers based on the matrix of the DP matching transition, and calculating similarity based on the maximum length.

1. Field of the Invention
The present invention relates to a pattern matching method and apparatus for performing Dynamic Programming (DP) matching of symbol sequences and to a speech information retrieval system.
2. Description of the Related Art
DP matching is well known as pattern matching used in the fields of information retrieval and speech recognition (for example, see Japanese Patent Application Laid-Open No. 11-282488). This is an approach for calculating the level of similarity between two symbol sequences using, as a measure of penalty, incorrectness (under operations of insertion, deletion, substitution, etc.) other than a coincidence or correct answer as a penalty.
The DP matching method mentioned above is used for calculating similarity between two symbol sequences to be compared. Specifically, if the two symbol sequences have different respective lengths and one of these symbol sequences contains another symbol sequence, the similarity is calculated to be low because it is calculated as having an insertion error. For example, if "aaabbb" and "aaa" are matched to each other, a penalty may be added taking into account the fact that there is an insertion of "bbb." Thus, matching using the DP method is not suitable in cases requiring a determination of whether or not "aaa" is contained in "aaabbb."
In order to perform matching between these symbol subsequences, a method in which no insertion error is simply taken into account is a possible approach. In this case, the similarity may however be the same both when there is a string of matching symbol sequences as a symbol subsequence, and when the symbol sequences appear apart from each other. For example, the same score (similarity) is obtained both in considering whether "ab" is contained in "acccb" and in determining whether "ab" is contained in "abccc."
To deal with this problem, in matching between symbol subsequences using the DP matching, a method for repetitively calculating while shifting the matching range is known. This method has a problem in that it requires a significant amount of calculation.

Pattern matching method and apparatus and speech information retrieval system


A striker assembly for use with a vehicle door latch is disclosed. The striker assembly may include a U-shaped strap that mounts to vehicle body structure, and a striker pin that is mounted to the strap. The striker pin may include a neck that is peened to form a head and neck that fills a countersunk pocket in a pin support arm of the strap. The strap may also have a base plate that mounts to vehicle structure and includes one or more water drain channels and a coined edge to better control water drainage and intrusion.

The present application relates generally to vehicle door latch and striker assemblies, and more particularly to a striker assembly that is attached to vehicle structure and engaged by a door latch when a vehicle door is closed.
Automotive vehicles are typically equipped with a door latch mounted in each door that engages a striker assembly mounted to vehicle structure, such as a vehicle door jam. The latch typically has a fish mouth slot that engages with a striker pin to hold the door in its closed position.
For some striker assemblies, a striker pin is attached to a U-shaped strap having a base that is bolted to the vehicle structure. The striker pin may have a shank that slides through the base, with a larger portion that bottoms in the base to retain the pin in the base, and an opposed end that is secured in a concentric hole through the other end of the strap. For various cost, performance, and aesthetic reasons, many of these prior striker assemblies are not as desirable as they could be.
The striker assemblies used in today's vehicles must not only satisfy strength and durability requirements, but must do so while still enabling the door system to perform satisfactorily under various environmental conditions, all while improving the visual aesthetics of the striker assemblies and providing a perceived quality feel for customers when opening and closing the vehicle doors.


The present invention discloses an image-projecting apparatus which employs an AF (auto-focusing) system suitable for use conditions of the image-projecting apparatus and is capable of securing satisfactory AF accuracy under bright conditions. The image-projecting apparatus comprises a projection optical system which projects light from an image-forming element onto a projection surface, and a detecting system which performs a detecting operation of a distance to the projection surface or a detecting operation of a focusing state of the projection optical system with respect to the projection surface. The detecting system determines a condition of the detecting operation on the basis of the light-receiving intensity level of the light-receiving element which receives reflected light from the projection surface of light projected and performs the detecting operation in accordance with the condition.

1. Field of the Invention
The present invention relates to an image-projecting apparatus such as a liquid crystal projector, etc. In particular, the invention relates to a technology for detecting a focusing state by receiving reflected light when projecting light onto a projection surface, which is a focusing detection technology in the case where the light to be detected is reflection light which derives from image projecting light of the image-projecting apparatus.
2. Description of Related Art
Conventionally, as an AF (Auto-Focusing) method of a projector, some methods have been known, one of which is an active method which performs auto-focusing based on a principle of triangulation-optical type focusing detection by using infrared light, and another of which is a passive method which reads a contrast of brightness on a screen by means of a pair of light-receiving sensors and driving a lens by obtaining correlation values of respective pixels output and obtaining a distance.
Also, the passive method of the AF method has two types classified in a large category, one of which is a so-called two-image correlation (or, displacement detection) AF method (Refer to Japanese Patent No. 3120526) which an parallax image such as an AF chart being an object for focusing detection is formed on a plurality of photo electric sensors disposed in a predetermined base length and performs obtaining and comparing of image information, and another method (hill climbing) which obtains the optimal state of focusing by imaging an object for focusing detection on a multi-pixel optical sensor having a one-dimensional or two-dimensional pixel arrangement and detects the image sharpness (contrast) from the image information, and driving the focusing position of a lens for forming the object image in the sensor.
In addition to the above, by using characteristics of a projector itself projecting an image, a technology which detects a specifically projected image by a camera and detects the focusing by comparing an original image information projected with an image-taking information (Refer to Japanese Patent Application Laid-Open No. 2000-28901).
Where projection light of such a projector itself is used for focusing adjustment, processing is performs under the same conditions as advantageous conditions of brightness regardless although disadvantageous brightness for the passive AF, the passive AF method can be performing unnecessarily erroneous detecting operation of a focusing.
For this reason, a number of technologies which change such as a determination algorithm, a focusing detecting operation and a focusing detecting method in accordance with a target object and environmental brightness, when focusing detection is performed (Refer to Japanese Patent No. 3272429 and Japanese Patent Application Laid-Open No.2001-317935).
In Japanese Patent No. 3272429, a focusing detecting apparatus which comprises a light emission unit which emits a light projected to a target object, a light emission output controller which controls light emitting output of the light emission, a first detector which receives reflected light from the target object and measuring the distance from the light-receiving position to the target object, and a determining unit which determines a dispersion of the distance measured a plurality of times by the first detector and the light emission output controller increases the light emitting output from the light emission unit when the dispersion determined by the determining unit exceeds a predetermined value.
Also, Japanese Patent Application Laid-Open No.2001-317935 relates to a distance-detector apparatus which detects the distance to a target object by receiving reflected light from the target object with light projected, the distance-detector apparatus comprises a detector which detects a light-receiving intensity level of the reflected light and a controller which determines the number of times of projecting and receiving light in accordance with the detected light-receiving intensity level and controls for performing repeated projected and receiving by the number of times. In the distance-detector apparatus, the lower the light-receiving intensity level becomes, the greater the number of times of projecting and receiving light increased, and measurement result information are calculated by executing an average processing calculation on the basis of information obtained by projecting and receiving by a plurality of times.
However, the respective technologies are based on an infrared LED as a projection light source and an apparatus driven a battery. The respective technologies do not disclose any technology to improve the AF accuracy, which is suitable for a distance detecting or focusing detecting method used for an image-projecting apparatus such as a liquid crystal projector, etc.
Specifically, as has been proposed in Japanese Patent No. 3272429, in the case where the light emitting output of the light emission unit is increased in auto focusing (AF), in the image-projecting apparatus such as a liquid crystal display, etc., it is necessary to employ a lamp suitable for output control as a lamp for illuminating image-forming elements such as a liquid crystal panel, etc., thus problems occur such a costs are increased and it is not realistic.
Further, as described above, in the image-projecting apparatus, auto focusing of a projection optical system is performed on the basis of signals output from a sensor by forming reflected light from a projection screen onto the sensor. However, if the original brightness of a screen on which no image is projected is high (that is, environmental brightness: which becomes brightness at an area other than the projection screen during projecting an image) even if the brightness of a projection surface is high, a contrast suitable for distance detection (or focusing detection) on the screen cannot be obtained.
Therefore, in a case where a distance-detecting apparatus proposed by Japanese Patent Application Laid-Open No. 2001-317935 is applied to an image-projecting apparatus and only distance detection (or focusing detection) is performed by the number of times in accordance with the light-receiving intensity level of light (sum of projection light and environmental light) from a projection surface, there are cases where a contrast suitable for distance detection (or focusing detection) cannot be obtained on the sensor, and it is impossible to securely improve the AF accuracy.


Method and device for determining one or more Z distances from an object surface to a reference plane, for example the primary plane of the primary objective of a microscope. By projecting an optical pattern onto an object, and subsequently detecting and computationally evaluating the object's reflection of this pattern by means of an image processing unit, it is possible to obtain relief-like imaging of the object and to identify the individual Z distances, irrespective of the object's contouring.

Determining the distance from an operation microscope to an object is very important, especially in surgery—for example in neurosurgical applications, since it is common for operations to be carried out with navigation systems and for the microscope to be used as a non-contact sensor. Once focusing has been carried out successfully via the defined measurement integral, for example, over a limited area around the focal point, a measured value can be sent to the navigation system, processed there and subsequently indexed in the data record of the object, which is generally the patient. In the currently known focusing systems, the working distance which is set once the image sharpness has been optimized is used for determining the working distance between a stereo microscope and the object surface. The evaluation of the image sharpness may be carried out in the entire field of view or in a restricted field of view, for example in a narrowly defined region around the centre of the field of view, normally a substantially point-like region with a diameter of approximately 1 to 2 mm. The focusing is normally carried out via the primary objective.

Method for measuring the separation of extended objects in conjunction with an optical observation system and microscope for carrying out the same


To provide a vacuum pump capable of evacuating in pressure ranges from an atmospheric pressure to a high vacuum, capable of rotating at a high speed to be downsized and improved in pumping performance, and capable of producing a completely oil-free vacuum.

1. Field of the Invention
The present invention relates to a vacuum pump, and more particularly to a vacuum pump capable of effective evacuation in pressure ranges from an atmospheric pressure to a high vacuum.
2. Description of the Related Art
FIG. 31 is a schematic diagram of a semiconductor manufacturing apparatus with a conventional vacuum pump.
As shown in FIG. 31, a semiconductor manufacturing apparatus 101 has a plurality of process chambers 102, a transfer chamber 103 and a cassette chamber 104. A wafer (substrate) to be processed is placed in the cassette chamber 104, transferred by way of the transfer chamber 103 to the process chamber 102, where it is subject to a predetermined process (such as PVD, CVD, and etching). A plurality of process chambers 102 are commonly provided in order to perform a plurality of processes or to increase the number of wafers to be processed in the single semiconductor manufacturing apparatus 101.
It is necessary to create a high vacuum state in the process chamber 102 before processing, and to exhaust a process gas continuously from the process chamber 102 during processing. To this end, a turbo molecular pump 105 is widely used as a vacuum pump for vacuum evacuation of the process chamber 102. While the turbo molecular pump 105 is operable in moderate and high vacuum ranges at the order of 101 Pa or below, it cannot operate independently under atmospheric pressure. Therefore, a backing pump 106 for preliminary evacuation is connected to the exhaust port of the turbo molecular pump 105 through piping 107. The backing pump 106 is configured to evacuate a gas at a pressure from atmospheric pressure to the order of 101 Pa.
A semiconductor manufacturing apparatus with the above configuration requires two types of vacuum pumps, namely the turbo molecular pump 105 and the backing pump 106, for each process chamber 102, as pumps for exhausting a gas therefrom. Therefore, there has been a problem of an increased space for installation, an increased number of components, a high cost, and so on. In recent years, the volume of gas used in semiconductor processing has tended to increase, which in turn has caused the vacuum pumps to be upsized, and the piping 107 to be upsized in diameter as well. Thus, the above problem becomes conspicuous.
There is mainly used a positive displacement pump, such as a roots pump, a screw pump, and an oil rotary pump, as the backing pump 106. This type of pump is configured that a rotor rotating at a relatively low speed reduces the volume of an exhaust flow passage in an exhaust chamber (casing) gradually to transfer a gas. Therefore, in order to increase the volume of gas transferred, the volume and the mass of the rotor need be increased, which unavoidably accompanies upsizing of the backing pump.
As measures for the above problem, there is a method in which the rotor is rotated at a high speed, in order to increase the volume of gas transferred without upsizing the backing pump. However, a roots pump and a screw pump have two main shafts, to each of which a rotor is fixed, and require a mechanism to constrain the rotation phases of the two main shafts (such as timing gear), and thus are not suitable for high-speed rotation. An oil rotary pump has an asymmetric rotor with respect to the rotation axis, and thus is not suitable for high-speed rotation, either. Thus, it is extremely difficult to downsize a backing pump with increasing the volume of gas transferred by causing the backing pump to rotate at a high speed.
In the above backing pumps, an oil such as lubricant is used in a bearing or a sealed portion, which hinders creation of a completely oil-free vacuum. This causes the quality and yield of products manufactured by the semiconductor manufacturing apparatus to be reduced.
In view of the above problems, Japanese Patent, JP-B-03-007039 discloses a vacuum pump capable of efficient vacuum evacuation from an atmospheric pressure to a high vacuum solely. The vacuum pump disclosed in the above Japanese Patent includes a centrifugal compression pump step having a plurality of impellers, and a circumferential flow compression pump step. However, the impellers are all attached to a tip of the main shaft, and therefore the rotor is a cantilever rotor with the tip of a large mass distribution. This deteriorates the vibration characteristics of the rotor and makes it difficult for the rotor to rotate at a high speed, causing a problem that the pump cannot be downsized. Furthermore, since a lubricant or the like is used in the bearing section, it was not possible to create a completely oil-free vacuum.
A vacuum pump disclosed in Japanese Patent, JP-B-07-086357 aims to adapt the rotor for high-speed rotation with the use of a magnetic bearing. However, since the magnetic bearing is located in the vicinity of an intake port, the magnetic bearing produces a resistance to exhaust gas, causing a problem that the exhaust performance of the vacuum pump was impaired. In particular, when the pressure on the intake port side is in the molecular flow range, the exhaust conductance reduces significantly, that is, the resistance to exhaust gas increases, causing a problem that the effective exhaust rate reduces conspicuously. Since a liquid coolant is introduced into a space connected to the exhaust flow passage of the pump, there also was a problem that the liquid coolant may contaminate the vacuum environment.
In the meantime, a turbo vacuum pump including a centrifugal drag pump element is occasionally used for vacuum evacuation of a process chamber of a semiconductor manufacturing apparatus. This type of turbo vacuum pump is described with reference to the drawings. FIG. 32 is a sectional view of a conventional turbo vacuum pump. FIG. 33(a) is a plan view of a centrifugal drag vane shown in FIG. 32, and FIG. 33(b) is a sectional view of the centrifugal drag vane shown in FIG. 32. FIG. 34(a) is a plan view of a fixed vane shown in FIG. 32, and FIG. 34(b) is a sectional view of the fixed vane shown in FIG. 32.
As shown in FIG. 32, the turbo vacuum pump comprises centrifugal drag vanes 133 constituting plural stages, a plurality of fixed vanes 134 disposed to face each of the stages of the centrifugal drag vanes 133, and a casing 108 having an intake port 111 and an exhaust port 131. The centrifugal drag vanes 133 are fixed to a main shaft 195, and are driven to rotate by a motor 123 through the main shaft 195. The main shaft 195 is supported in a non-contact manner by an upper radial magnetic bearing 122, a lower radial magnetic bearing 144, and an axial magnetic bearing 143. An upper touchdown bearing 126 and a lower touchdown bearing 147 are disposed above the upper radial magnetic bearing 122 and below the lower radial magnetic bearing 144, respectively.
As shown in FIG. 33(a) and FIG. 33(b), each of the centrifugal drag vanes 133 has a plurality of spiral blades 135 extending rearward with respect to the rotation direction, and a disk-shaped base 109 to which the spiral blades 135 are fixed. On the other hand, as shown in FIG. 34(a) and FIG. 34(b), the fixed vane 134 has a plurality of spiral guides 166 extending rearward with respect to the rotation direction of the centrifugal drag vanes 133, and an annular plane portion 167 to which the spiral guides 166 are fixed. The arrows G shown in FIG. 33(a) and FIG. 34(a) indicate the flow of a gas.
When the centrifugal drag vanes 133 are rotated in the direction of the arrow Q, a gas is drawn into the casing 108 from the intake port 111, and is compressed as it is transferred toward the radially outer side through action of a centrifugal force. The gas having been transferred to the radially outer side, then flows into a space defined by the spiral guides 166, the plane portion 167, and the backside of the base 109, and the gas is compressed as it is transferred toward the radially inner side through drag action due to viscosity of the gas. In this manner, the gas is transferred at each stage to be compressed to a desired pressure, and discharged through the exhaust port 131.
In the conventional turbo vacuum pump, however, since the number of stages of the vanes was simply increased to improve the exhaust performance, the exhaust efficiency remained low. Therefore, a problem was raised that the exhaust rate reduced and that the compression ratio remained low, which as a result caused upsizing of the entire turbo vacuum pump and an increase in manufacturing costs.
The present invention has been made in view of the foregoing, and it is therefore an object of the present invention to provide a vacuum pump capable of evacuating in pressure ranges from an atmospheric pressure to a high vacuum, capable of rotating at a high speed to be downsized and improved in pumping performance, and capable of producing a completely oil-free vacuum.

Vacuum pump and semiconductor manufacturing apparatus

Abstract: A vacuum pump for exhausting a gas comprises: a main shaft 5 rotatably supported by a bearing 22; a motor 23 for driving the main shaft 5 for rotation; a first exhaust section 10 having a first rotary vane 13 attached to the main shaft 5, a first fixed vane 14 fixed in a first casing 12, and an intake port 11; and a second exhaust section 30 having a second rotary vane 33 attached to the main shaft 5, a second fixed vane 34 fixed in a second casing 32, and an exhaust port 31. The intake port 11 is located in the vicinity of an end of the main shaft 5, and the first exhaust section 10, the bearing 22 and the second exhaust section 30 are arranged in this order axially along the main shaft 5.


In a technique to improve the high-frequency power gain of an LDMOS, the distance from the surface of a passivation film covering electrode pads to the rear surface of a silicon substrate is set into 200 μm or less, or a trench of 2 μm or more in thickness, in which an insulating film or a conductor is embedded, is formed between a region where a p type impurity is diffused, when a p+ type source penetrating layer is formed, and the channel region of a third LDMOS, so as to extend from the front surface of a semiconductor layer toward a silicon substrate. This trench restrains the p+ type source penetrating layer from spreading to the channel region, thereby lowering the inductance or the resistance of the source and improving the high-frequency power gain.

The present invention relates to a semiconductor device and to a technique for manufacturing the same; and, in particular, the invention relates to a semiconductor device having laterally diffused metal oxide semiconductor field effect transistors (LDMOS•FETs) and to a method of manufacturing the same.
In recent years, LDMOS•FETs (hereinafter referred to merely as LDMOSes) have been used to amplify high-frequency electric power for portable telephone base stations or digital television station transmitters, instead of bipolar transistors, since the LDMOSes produce various advantages, such as simplification of the bias circuits or the provision of high power gain.
An LDMOS is formed in a p-epitaxial layer grown on a p+ substrate, and it is composed of a gate, an n+ source region reaching the bottom of one end of the gate, an n− drain region reaching the bottom of the other end of the gate, an n+ drain region spaced from the latter gate end by the length of the n− drain region, and a p well wherein a channel region is formed.
Although the n+ source region and the n+ drain region of the LDMOS are positioned on the front surface of the chip, a source electrode is formed in the p+ substrate in the rear surface of the chip. Therefore, the n+ source region is connected to the p+ substrate in the rear surface of the chip through a low-resistance p+ source penetrating layer that is diffused in the horizontal direction or a conductor (see, for example, Patent Document 1). The connection of the n+ source region to the p+ substrate through the low-resistance p+ source penetrating layer or the conductor causes a reduction in the inductance or the resistance of the n+ source region so as to prevent the high-frequency power gain of the LDMOS from being lowered.
[Patent Document 1]
Japanese Patent Application Laid-Open No. Hei 5(1993)-218321
In order to obtain a higher gain in the LDMOS, it is necessary that the inductance or the resistance of the n+ source region is made low by at least one of the following methods: (1) the thickness of the p+ substrate is made small; (2) the plane area of the p+ source penetrating layer is enlarged; and (3) the concentration of the p+ source penetrating layer is made high. However, the inventors have found that these methods (1) to (3) have the following problems.

Semiconductor device and a method of manufacturing the same


A method, apparatus and computer program product are provided to facilitate interworking a plurality of cellular radio access networks and wireless local area networks (WLANs). In the context of a method, a set of information is maintained for a plurality of different cellular radio access networks that defines a relative priority of selection among the cellular radio access networks. The method also includes maintaining wireless access selection information defining a relative priority of selection among one or more WLANs relative to the cellular radio access networks. The method also permits the relative priority of the WLANs to be modified without modification of the set of information. For example, the relative priority the WLANs may be modified in a manner specific to the user equipment or specific to a cell. The method may also include causing notification to be provided to user equipment of the set of information and the wireless access selection information.

A variety of access networks may be utilized by user equipment in order to access a core network. For example, user equipment may utilize a variety of cellular radio access networks, such as long term evolution (LTE) radio access networks and universal mobile telecommunications system (UMTS) radio access networks as well as second generation (2G) radio access networks. Additionally, the different types of radio access networks may also operate at different frequencies such that LTE radio access networks may be provided that operate at 800 MHz, 2100 MHz and 2600 MHz.
In order to facilitate selection of a radio access network, one or more radio access technology (RAT) and frequency selection priority (RFSP) profiles may be defined. Each RFSP profile defines a prioritized ordering of radio access networks such that user equipment may attempt to utilize radio access networks to access a core network in the prioritized order set forth by the respective RFSP profile. Each profile may be identified by an RFSP index. The set of RFSP profiles may be initially provided by the network, such as a mobility management entity (MME) or the home subscriber server (HSS), and may be stored both by the network, such as an access point, e.g., a node B or evolved Node B (eNB), that serves the user equipment (UE), as well as the user equipment itself. The set of RFSP profiles to be utilized by the user equipment may be identified by a RFSP index that is provided by the network, such as by the MME or the HSS subscription profile, and is delivered to the user equipment, such as in the idle mode MobilityControl information element (1E) broadcast in the system information message.
An increasing number of wireless local area networks (WLANs) are being deployed and being utilized by WLAN stations (STA) with the trend toward increasing Wi-Fi usage expected to continue. Mobile devices may include the WLAN station capabilities and cellular user equipment capabilities, the capabilities of which may be independent of each other and may be selected suitable for a given device type. Generally, any device communicating in said networks is referred to herein as user equipment. As such, user equipment is more frequently faced with the decision as to whether to utilize a cellular radio access network, such as an LTE cell, or a WLAN. The choice between a cellular radio access network and a WLAN has typically been governed by the user of the user equipment, such as by user settings or configurations or by concrete momentary choices by the user. In some instances, the selection among cellular radio access networks or WLAN networks may be assisted by a network server, such as the access network discovery and selection function (ANDSF) server, that may store the preferences set by the operator for the user. Among other things, the user settings or configurations or the user's preferences as maintained by the ANDSF server may generally define selection criteria, Inter System Routing Policies (ISRP), selection thresholds and network preferences, e.g., service set identifier (SSID), etc. for different locations or geographical areas. However, interworking between the radio access networks and WLANs is limited and, in any event, is relatively static. Often these choices are ON/OFF selections for either enabling the use or disabling the use of one, e.g., either the cellular radio access networks or the WLANs, while having an independent choice for the other.

Method and apparatus for facilitating interworking of cellular radio access networks and wireless local area networks


Bulk gallium arsenide having a high hold-off voltage is optically activated by a laser resulting in high power output. A high voltage input is applied to a semi-insulating gallium arsenide material. The gallium arsenide material is activated by laser light, thereby resulting in large current conduction. An external oscillating signal is superimposed on the high current resulting in a high power output.

1. Field of the Invention
This invention relates generally to high peak power oscillating signals, and particularly to a high power microwave device.
2. Description of the Prior Art
As electronic devices and microwave devices in particular become more sophisticated, and are applied to more applications, more power is increasingly desired. The Gunn-effect diode is used to produce oscillating signals due to the periodic nucleation and disappearance of traveling space-charge instability domains. The Gunn-effect diode is made of an n-type GaAs, gallium arsenide, material. N-type gallium arsenide material has free electrons ranging from 10.sup.14 to 10.sup.17 per cubic centimeter at room temperature.
Two references that disclose the use of semiconductors to provide an oscillation of current are, J. B. Gunn, "Microwave Oscillation of Current in III-V Semiconductors", Solid State Communications, Vol. 1, pp 88-91, 1963; and R. Pastore and M. Weiner, "RF Oscillation in Optically Activated GaAs", Record of 7th IEEE Pulse Power Conference, Jun. 1989, pp 872-874. In the R. Pastore and M. Weiner article, a cavity is used to couple the gallium arsenide to the cavity fields. Therefore, the frequency is determined by the cavity adjustment, and the device operates as an oscillator.
While these semiconductor devices for producing oscillation of current resulted in devices useful for their intended purpose, they are not suitable for all applications. In the n-type gallium arsenide devices, power is limited by the voltage hold off capabilities of the n-type gallium arsenide. Additionally, n-type gallium arsenide devices have a high dark current due to relatively high concentration of free electrons. When high power is desired, and high input voltage used, high dark currents are induced resulting in undesirable thermal heating effects. The undesirable thermal heating effects will eventually lead to thermal runaway, and a destruction of the device.
Therefore, there is a need for an improved high power device for amplifying a signal.

Signal amplification using optically activated bulk semi-insulating GaAs

The United States of America as represented by the Secretary of the Army


This invention relates to optical elements capable of second harmonic generation and novel compositions for use in such optical elements comprising polar molecules placed in noncentrosymmetric configuration wherein such optical element has an electron donor moiety linked through a conjugated bonding moiety to an electron acceptor moiety which consists of a selected fluorinated sulfone, fluorinated ketone, fluorinated vinyl sulfone or fluorinated alkyl vinyl sulfone.

It has been recognized that certain media having a polarization susceptability provide sensitive ways of manipulating beams of incident electromagnetic radiation. Such media are said to possess nonlinear polarization. The size of the effects attributable to such nonlinear polarization depends on the arrangement of electrically charged particles (electrons, ions and nuclei) within the media. To obtain the highest nonlinear polarization property of a medium, the molecules within the medium must be arranged so that the nonlinear properties of the individual polar molecules within the medium do not cancel each other out.
On a molecular level the polarization of a medium can be described by the following expression: EQU .mu.=.mu..sub.0 +.alpha.E+.beta.EE+.gamma.EEE+
where
.mu. is the induced dipole moment PA1 .mu..sub.0 is the permanent dipole moment PA1 E is local electric field PA1 .alpha., .beta., and .gamma. are tensors representing the linear, second order and third order polarizabilities, respectively. .beta. and .gamma. are also referred to as the first and second hyperpolarizabilities, respectively. PA1 P is the induced polarization PA1 P.sub.0 is the permanent polarization PA1 E is the applied electric field PA1 .chi..sup.(1), .chi..sup.(2) and .chi..sup.(3) are tensors representing the linear, second order and third order polarization susceptibilities, respectively. PA1 .chi..sup.(2) arises from the second order molecular polarizability or first hyperpolarizability, .beta., and .chi..sup.(3) arises from further hyperpolarizabilities, etc. As tensor quantities, the susceptibilities, .chi..sup.(i), are highly symmetry dependent; odd order coefficients are nonvanishing for all materials, but even order coefficients, e.g., .chi..sup.(2) are nonvanishing only for noncentrosymmetric materials. PA1 Z.sup.1, Z.sup.2, Z.sup.3, Z.sup.4 and Z.sup.5 are individually selected from H, alkyl of 1 to 20 carbon atoms, aryl, OR.sup.2, SR.sup.3 and NR.sup.4 R.sup.5, PA1 R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are individually selected from aryl, alkyl of from 1 to 20 carbon atoms, and COR.sup.6, wherein R.sup.6 is selected from H, aryl, and alkyl of from 1 to 20 carbon atoms, PA1 X and Y are the same or different and are individually selected from H, F, Cl, Br, I, alkyl and fluoroalkyl of 1 to 20 carbon atoms, aryl, fluoroaryl, SR and OR.sup.7, wherein R.sup.7 is selected from alkyl of 1 to 20 carbon atoms and aryl, PA1 with the following provisos (1) for structures 1 and 4 that when D is NH.sub.2, F, Br, NH(C.sub.2 H.sub.5), N(CH.sub.3).sub.2, OCH.sub.3, OH or SH, X is not F and Y is not a fluoroalkyl of less than 7 carbon atoms; (2) for structure 7 that when D is H, p--Cl, p--F, m--F, p--NO.sub.2 or p--NH.sub.2 and X and Y are not F; and (3) for structure 8 that when D is OC.sub.n H(2n+1), n is not 1.
On the molecular level first order or linear polarization is described by .alpha.E; second order or first nonlinear polarization by .beta.EE; and third order or second nonlinear polarization by .gamma.EEE.
The polarization of an ensemble of molecules induced by an applied electric field can be described by the following expression: EQU P=P.sub.0 +.chi..sup.(1) E+.chi..sup.(2) EE+.chi..sup.(3) EEE+
where
Franken et al., Physical Review Letters, 7, 118-119 (1961), disclose the observation of second harmonic generation (SHG) upon the projection of a pulsed ruby laser beam through crystalline quartz. The use of a laser remains the only practical way to generate an E large enough to be able to detect the SHG phenomenon.
Second order nonlinear optical phenomena, such as SHG, sum and difference frequency generation, parametric processes and electro-optical effects, all arise from the .chi..sup.(2) term. Consequently, for significant nonlinear optical phenomena it is desirable that a molecule possess a large hyperpolarizability, .beta., and that an ensemble of such molecules possess a large .chi..sup.(2).
The art has recognized that organic molecules having conjugated .pi.-electron systems or low-lying charge transfer excited states often have extremely large hyperpolarizabilities, but unfavorable alignment of the molecules in the crystalline phase, in thin films or in other forms can result in a centrosymmetric material in which the .chi..sup.(2) vanishes. This problem may be circumvented by using a chiral molecule to insure a noncentrosymmetric (i.e., symmetrical about its center) crystal, but problems associated with the creation and maintenance of a high level of optical purity limit the value of this approach. In addition, optical activity per se does not guarantee that .chi..sup.(2) will be large, only that it will not be zero.
One approach to the problem disclosed by Anderson et al. U.S. Pat. No. 4,818,898 involves the formation of inclusion complexes consisting of a crystalline lattice forming host compound with continuous channels containing a nonlinearly polarizable guest compound having a second order polarizability greater than 10.sup.-30 electrostatic units.
Ulman et al. U.S. Pat. No. 4,792,208 discloses an optical article containing a medium exhibiting a second order polarization susceptibility greater than 10.sup.-9 electrostatic units comprised of polar aligned noncentrosymmetric molecular dipoles having an electron donor moiety linked through a conjugated .pi. bonding system to an electron acceptor moiety to permit oscillation of the molecular dipole between a lower polarity ground state and a higher polarity excited state. A wide variety of donor and acceptor moieties are disclosed with a sulfonyl electron acceptor group in combination with a hydrocarbon substituted electron donor group preferred. The second order nonlinearity is achieved by the polar alignment of the molecular dipoles, in, for example, polymeric binders, to form Langmuir-Blodgett (LB) films.
While the art continues to investigate the alteration of chemical structure to continuously increase molecular nonlinearity and corresponding molecular dipole moment, this approach may not always produce the material having the best combination of overall properties. Large dipole moment, which favors strong polar alignment, can often be associated with aggregation and solubility problems, allowing only a small amount of optically active material to be contained in a binder. Furthermore alterations in chemical structure to increase nonlinearity can often adversely effect the color of the resulting material. Since the first and second harmonic wavelengths of diode lasers lie near 800 and 400 nanometers, respectively, the optimum nonlinear molecules must have high transparency, i.e., very low absorption at these wavelengths, and, in addition, possess high photochemical stability under the conditions of exposure to high optical intensities. One of the major chemical challenges in this area of technology is to discover molecules that have high nonlinearity, but absorb very little light over the visible range of wavelengths from 350 to 850 nanometers.
Accordingly, it is an object of this invention to provide a novel nonlinear optical medium which exhibits a high transparency over the visible range of wavelengths.
It is another object of this invention to provide a nonlinear optical element comprising a transparent medium selected from fluorinated sulfones and fluorinated ketones.
It is a further object of this invention to provide a novel composition which is a physical blend of fluorinated sulfones or ketones with a polymer component.
It is an additional object to provide an apparatus for second harmonic generation.
These and other objects and advantages will become apparent from the accompanying description and examples.

Fluorinated sulfones/ketones for nonlinear optics


A clip (1, 101, 201, 301) for securing a seat cover (304) to a foam part (303) of a seat cushion, including at least one securing element (1.2, 101.2, 201.2, 301.2, 1.6) for temporarily securing the clip (1, 101,201,301) to a foaming tool (SW) in a form-fitting manner. A foaming tool (SW) is provided for producing a foam part (303) of a seat cushion. A production arrangement (HS) is provided for producing a foam part (303) of a seat cushion, and a method is provided for producing a foam part (303) of a seat cushion.

Clips for fastening a seat cover to a foam part of a seat cushion are generally known from the prior art. These clips are foamed in place in the foam part of the seat cushion during production of the foam part. The seat cushion is then fastenable to the clips.

Clip for fastening a seat cover to a foam part of a seat cushion, foaming tool, production arrangement, and method for producing a foam part of a seat cushion


A liquid crystal display device includes a liquid crystal layer interposed between opposing substrates. One of the substrates includes a conductive black matrix layer formed within a display region and formed in non-display region of the device. A black matrix island formed at the same time as the black matrix layer is isolated from the black matrix layer in the non-display region. A color filter layer of red, green and blue color filters is formed in the display region. A common electrode is formed on the black matrix layer and on the black matrix island. The common electrode formed on the black matrix island is insulated from the black matrix island by an insulator. Silver dots in the non-display region are respectively connected with the black matrix layer and the common electrode on the black matrix island.

1. Technical Field
The present invention relates to a liquid crystal display device (LCD), and more particularly, to an LCD that mitigates electromagnetic interference (EMI), and a fabrication method thereof.
2. Related Art
In general, display devices have used a cathode ray tube (CRT) to display image information on a screen. However, CRT displays are problematic as they take up a large volume and are extremely heavy compared with the display area.
With the rapid development of the electronics industry, the importance of the CRT display devices has decreased. Various electronic devices such as a personal computer, a notebook, a wireless terminal, a vehicle instrument panel, an electronic display board and the like now require much lighter and smaller displays than that afforded by the CRT. Also, due to the development of information communication technology, since it is possible to transmit large capacity image information, the importance on a next generation display device capable of processing and displaying the large capacity image information has increased dramatically.
Such a next generation display device ideally has a slim profile, is lightweight, has a high luminance, a large-sized screen, a low power consumption and a low price. Among such next generation display devices, the liquid crystal display (LCD) is extremely popular due to its excellent resolution, which is better than other flat displays, as well as the fact that its response rate is fast, that is, considerable to that of the CRT in implementing a moving picture.
The LCD generally displays images using light transmittance that varies when a voltage is applied to electrodes of two substrates facing each other to generate an electric field between the electrodes. This electric field aligns liquid crystal molecules disposed between the electrodes.
The LCDs can be made in a variety of structures and materials. An active matrix LCD (AM-LCD) including thin film transistors (TFTS) and pixel electrodes connected with the TFTs is currently in the limelight owing to its excellent resolution and moving picture-implementing capability.
FIG. 1 is a sectional view of a general LCD. Referring to FIG. 1, a general LCD includes an array substrate 110, a color filter substrate 120, and a liquid crystal layer 130 interposed between the two substrates 110 and 120.
The array substrate 110 includes a gate electrode 112 and a gate insulating layer 113. The gate electrode 112 is formed of conductive material such as metal on a first transparent substrate 111. The gate insulating layer 113 covers the gate electrode 112 and is formed of silicon nitride layer (SiNx) or silicon oxide layer (SiO2).
An active layer 114 is formed on the gate insulating layer 113, and an ohmic contact layer 115 is formed on the active layer 114. The active layer 114 is formed of undoped (i.e. unintentionally doped) amorphous silicon, and the ohmic contact layer 115 is formed of intentionally doped amorphous silicon.
Source and drain electrodes 116a and 116b are formed on the ohmic contact layer 115 and constitute a thin film transistor T together with the gate electrode 112. The source and drain electrodes 116a and 116b are formed of conductive material such as metal.
Although not shown, the gate electrode 112 is connected to a gate line, and the source electrode 116a is connected to a data line. The gate line and the data line are perpendicular to each other. The gate line and the data line define a pixel region.
A passivation layer 117 is formed on the source and drain electrodes 116a and 116b and it has a contact hole 117c exposing the drain electrode 116b. The passivation layer 117 is formed of a silicon nitride layer, a silicon oxide layer, or an organic insulating layer.
A pixel electrode 118 is formed on the pixel region and is connected to the drain electrode 116b through the contact hole 117c. The pixel electrode 118 is formed of a transparent conductive material.
The color filter substrate 120 is spaced apart from the first substrate 111 by a predetermined distance. The color filter substrate includes a second substrate 121. A black matrix layer 122 is formed in an inner side of the second substrate 121 at a position corresponding to the thin film transistor T. Although not shown, the black matrix 122 is formed on a front side of the substrate and has an opening at a position corresponding to the pixel electrode 118.
Accordingly, the black matrix layer 122 prevents light leakage, which occurs when liquid molecules are tilted in a region other than the region covered by the pixel electrode 118. Also, the black matrix layer 122 blocks light from being incident on a channel region of the thin film transistor T, thereby preventing light leakage current.
A color filter 123 is formed on the black matrix layer 122. The color filter layer 123 includes red, green and blue color filters, which are repeated in sequence. One color corresponds to one pixel electrode 118. A common electrode 124 is formed of a transparent conductive material below the color filter layer 123.
A method for manufacturing the LCD includes forming a thin film transistor and a pixel electrode on an array substrate, forming a color filter layer and a common electrode on a color filter substrate, arranging the substrates, injecting liquid crystal between the substrates, sealing the substrates, and attaching polarizers to the substrates. In such an LCD, the pixel electrode 118 is formed on the array substrate 110 and the common electrode is formed on the color filter substrate 120. Liquid crystal molecules are driven by an electric field applied in a direction perpendicular to the substrates.
FIG. 2 is a view schematically illustrating a portion of a color filter substrate in an LCD according to the related art. Only one edge of the second substrate is shown in FIG. 2. In FIG. 2, a color filter substrate includes an active region A, which corresponds to an image display region formed on the array substrate. Electrical signals are applied to a variety of elements using a region formed at a periphery of the active region.
As shown, a black matrix layer 122 is formed on the color filter substrate. The black matrix layer 122 prevents light leakage between cells of color filter patterns and at a periphery of the active region A.
Patterns of red (R), green (G) and blue (B) color filters 123 are formed on the active region A of the black matrix layer 122. An overcoat layer 130 for insulation and planarization of the layers thereunder is coated to a predetermined thickness on the substrate on which the color filter patterns are formed. A common electrode 124 is formed on the overcoat layer 130 so as to operate liquid crystal cells together with a pixel electrode formed on a lower TFT substrate.
In order to apply signals from a pad part of a lower substrate to the common electrode 124, a common voltage (Vcom) Ag dot 142 is formed at a position that is in contact with the common electrode 124 formed on the black matrix 122.
FIG. 3 is a partial sectional view of the color filter substrate, taken along line I–I′ of FIG. 2. Referring to FIG. 3, the color filter substrate includes the black matrix layer 122 formed on the transparent insulating substrate 121, the color filter layer 123 of red, green and blue color filters, the overcoat layer 130, and the common electrode 224, which are sequentially formed on the black matrix layer 122. As shown, the Vcom Ag dot 142 is formed at a position that is in contact with the common electrode 124 formed on the black matrix 122.
A conventional LCD with such an arrangement has a good transmittance and aperture ratio. The common electrode 124 acts as ground and prevents breakdown in the liquid crystal cells due to a charge buildup between the substrates. In the conventional LCD, however, a very fast electric change occurs when an image display signal is applied, so that a large amount of electromagnetic interference (EMI) occurs.
Although electromagnetic radiation is useful in wireless communication or radar applications, unintended electromagnetic radiation occurring inside a variety of electronic devices containing the LCD may influence the operation of the electronic devices containing the LCD as well as the operation of other electronic devices present. As a result, operation of the electronic devices may be interrupted or the electronic devices may otherwise malfunction. Further, if the electromagnetic components are radiated or transported through connections between the LCD and other parts of the electronic device, the picture or tone quality of the LCD may be degraded.

Liquid crystal display device and fabrication method thereof


The present invention relates to an antenna for WWAN and an integrated antenna for WWAN, WLAN, and GPS. The integrated antenna comprises a ground metal plate, a coupled WWAN antenna, a WLAN antenna, an auxiliary grounding element, and at least one supporting element. The integrated antenna of the invention can be applied to a wireless electronic device with WWAN and WLAN by utilizing the coupled WWAN antenna to induce a WWAN frequency and the WLAN antenna to induce a WLAN frequency. In addition, the ground metal plate and the auxiliary grounding element are selectively connected or not connected to a ground end of the wireless electronic device, and can be separately used to provide grounding effect. Therefore, the integrated antenna can be mounted on any part of the wireless electronic device, and can have stable electrical characteristic.

1. Field of the Invention
The present invention relates to an antenna for wireless networks. More particularly, the present invention relates to an antenna for WWAN or an integrated antenna for WWAN and WLAN.
2. Description of the Related Art
With the rapid development of wireless communication technology, various multi-frequency communication products appear constantly. Therefore, wireless communication products have gradually become a part of daily life. Almost all the new products have been provided with the wireless transmission function to satisfy people's requirements. Notebook computers often perform data transmission. Since wireless transmission has the advantage of simplifying troubles in wiring and setting, the arrangement of antennas is required to achieve wireless transmission. However, the wide acceptance of notebook computers with the function of wireless transmission relies much on the appearance, size, and performance of the products, which are all very important points. Thus, the favorable design of antennas and suitable positions for their placement are especially important.
A conventional antenna arrangement for notebook computers, for example, is disclosed in U.S. Pat. No. 6,339,400B1, in which one or more antennas 11, 12 are disposed around a screen 10 of a notebook computer 1, as shown in FIG. 1. However, since the ground ends of the antennas 11, 12 must be connected to the ground of the screen or the frame of the screen, the conventional design of antenna arrangement has a limitation in the installation site, i.e. the installation site cannot be flexibly adjusted. Moreover, the antennas 11, 12 can only be applicable to WLAN.
Therefore, it is necessary to provide an antenna suitable for WWAN or suitable for both WWAN and WLAN in order to solve the above problem.

Antenna for WWAN and integrated antenna for WWAN, GPS and WLAN


A photoelectric sensor having a photoconductive layer on an electrode and used to form information on an information recording medium. The photoelectric sensor is semiconductive and has such a function that when a voltage is applied between the electrode of the photoelectric sensor and an electrode of the information recording medium while information exposure is being carried out, or when information exposure is carried out with a voltage being applied between the two electrodes, information can be recorded on the information recording medium with an electric current amplified to a level higher than the intensity of a photoelectric current induced by the information exposure, and that even after termination of the information exposure, when the voltage is continuously applied, the photoelectric sensor shows electrical conductivity and continuously effects information recording to the information recording medium. The photoelectric sensor has a photo-induced current amplifying layer provided between the electrode and the photoconductive layer, thereby enabling an image free from unevenness and noise to be formed with high sensitivity.

The present invention relates to a photoelectric sensor capable of recording light information on an information recording medium in the form of visible information or electrostatic information. More specifically, the present invention relates to a photoelectric sensor having on an electrode a photo-induced current amplifying layer which has photo-induced current amplifying action and/or injection current stabilizing action. The present invention also relates to an information recording system including the photoelectric sensor and an information recording medium, and to an information recording and reproducing method which employs the information recording system. More particularly, the present invention relates to an information recording system including a photoelectric sensor having a photo-induced current amplifying layer that markedly amplifies the information recording performance with respect to an information recording medium, thereby making it possible to obtain a predetermined image density and eliminate unevenness of the recorded image and generation of image noise, and also relates to an information recording and reproducing method which employs the information recording system.
There has heretofore been an information recording and reproducing method in which a photoelectric sensor having a photoconductive layer provided with an electrode on the front side thereof is disposed to face, on an optical axis, an information recording medium having an electric charge retaining layer provided with an electrode on the rear side thereof, and exposure is carried out with a voltage being applied between the two electrodes, thereby enabling electrostatic charge corresponding to the incident optical image to be recorded on the electric charge retaining layer, and then the recorded electrostatic information is reproduced by toner development or electric potential reading method, as described, for example, in Japanese Patent Application Laid-Open (KOKAI) Nos. 01-290366 and 01-289975. There is another conventional information recording and reproducing method in which the electric charge retaining layer in the above-described method is replaced by a thermoplastic resin layer, and after electrostatic charge has been recorded on the surface of the thermoplastic resin layer, heating is carried out to form a frost image on the surface of the thermoplastic resin layer, thereby making the recorded electrostatic charge visible, as described, for example, in Japanese Patent Application Laid-Open (KOKAI) No. 03-192288.
The present applicants have developed an information recording and reproducing method in which the information recording layer of the above-described information recording medium is a polymer dispersed liquid crystal layer, and in which exposure is carried out under voltage application in the same way as the above, and the molecules in the liquid crystal layer are aligned by an electric field formed by a photoelectric sensor, thereby effecting information recording, and the recorded information is reproduced as visible information by transmitted or reflected light. With regard to the information recording and reproducing method, we have filed applications as Japanese Patent Application Nos. 04-3394, 04-24722 and 05-266646. This method enables the recorded information to be made visible without using a polarized light plate.
For these information recording methods, there has been a demand for a photoelectric sensor which enables information recording of higher sensitivity, higher resolution and higher image quality. There has also been a demand for a photoelectric sensor of high resolution and high sensitivity which provides a highly stable base current and photo-induced current and which is free from unevenness of sensitivity and noise, thereby enabling an image to be formed at a predetermined image density without scumming.
It is an object of the present invention to provide a photoelectric sensor used to form information on an information recording medium, which has superior information forming power and improved information recording sensitivity, whereby it is possible to obtain an image of high quality which is free from image density variation, sensitivity unevenness and noise, which are particularly noticeable problems in photoelectric sensors of high resolution and high sensitivity, and to provide an information recording system including the photoelectric sensor, and an information recording and reproducing method which employs the information recording system.

Photoelectric sensor, information recording system and information recording and reproducing method


A method and an electronic device for detecting crosstalk data are provided. The method for detecting crosstalk data can detect whether an audio data stream includes crosstalk data. The method includes: receiving a first audio data block, a second audio data block, and a reference time difference, wherein the first audio data block and the second audio data block separately include a plurality of audio data segments; using a time difference between an acquisition time of an audio data segment in the first audio data block and a corresponding audio data segment in the second audio data block as an audio segment time difference; and determining that the audio data segment of the first audio data block includes crosstalk data when the audio segment time difference does not match the reference time difference.

In real life, people get together to communicate and discuss matters. In some scenarios, a microphone can be used to amplify a sound source, and multiple microphones on a site can collect audio data for each character. In some cases, crosstalk may occur when two or more microphones are very close to each other.

Crosstalk data detection method and electronic device


A roller bearing having two cooperating rolling parts of which one is of ceramic and the other of a steel. The steel part is of such structure and/or material and/or is so produced to cause residual compressive stresses to form beneath the contact surface of the steel part, at least in a load-free state, down to a depth.

Accordingly, the invention relates to hybrid bearings. Hybrid bearings are rolling bearings which have bearing rings, or at least the raceways of the bearing rings, made from steel and which are provided with rolling bodies made from ceramic, or in which at least one bearing ring is made from ceramic and the rolling bodies are made from steel.
The materials used for the ceramic rolling bearing element are all industrial ceramics, in particular silicon nitride (Si3N4), but also silicon carbides and also aluminum and zinc oxides. The use, construction and advantages and disadvantages of using hybrid bearings are extensively described in the publication by FAG Kugelfischer Georg Schäfer KGaA, Publ. No. WL 40 204 DA 80/11 from 1990 "Hochleistungskeramik in FAG Wälzlagern" [High-performance ceramics in FAG roller bearings].
Excellent properties of ceramic for use as roller bearing material for roller bearing parts which are subject to high and extremely high loads include properties such as low weight, low thermal expansion, high hardness and heat resistance, good dimensional stability at extremely high temperatures, high chemical resistance and high corrosion resistance, high modulus of elasticity, lower frictional torque at high rotational speeds and lower heat production, lack of magnetism and insulator properties.
The centrifugal force of the rolling bodies should also be taken into account when determining the loads on fast-moving roller bearings. At very high rotational speeds, such as for example for applications in driving mechanisms, the centrifugal forces are generally even dominant over the bearing loads. On account of the low weight of ceramic, at high rotational speeds the centrifugal forces generated are lower at rolling bodies made from ceramic. The density of ceramic, for example silicon nitride, is only approx. 40% of the density of steel.
Ceramic materials have a significantly higher modulus of elasticity, for example 1.5 times, than steel. Consequently, for the same loading, the specific stress in the rolling contact is higher than with contact parts made from steel, since the pressure ellipse produced by the ceramic rolling bodies in the rolling contact is smaller. In general, therefore, rolling pairings in which both components are made from ceramic, and in particular rolling pairings in which one rolling part is made from steel and the other is made from ceramic, are not able to withstand as high a load as rolling pairings in which both contact parts are made from steel.
Components made from ceramic have a fundamentally different failure mechanism than components made from roller bearing steel. On account of the brittleness of the ceramic material, in the event of overloading, ceramic fractures without any significant plastic deformation. This property has caused the person skilled in the art to consider that in the event of damage to components made from ceramic, such as small pieces of the surface breaking off, in a roller bearing, the ceramic components will be the first to suffer extensive damage, and the steel components will only undergo such damage at a later stage, as a secondary phenomenon. However, as has emerged and as has also been described in the prior art cited above, under certain circumstances ceramic components which have suffered preliminary damage as a result of impurities and inclusions and pores, cracking nuclei and microcracks and overloading and/or as a result of foreign particles in the rolling contact, have initially proven to still have a long service life. The abrasion of the ceramic and/or particles which have broken out of the surface of the ceramic component in some cases act as an abrasive on the raceways made from steel or pass into the rolling contact, where they first of all damage outer layers of the rolling parts made from steel.
The sensitivity of the surfaces of the roller bearing parts made from steel is dependent on the nature and magnitude of the stresses prevailing at and below the surface (in the outer layer). In this context, the term nature is to be understood as meaning residual stresses (tensile or compressive stresses) in the outer layer of the component or stresses acting on the component as a result of external action. Tensile stresses at the surface and in the outer layer below the surface increase the sensitivity of the component. Tensile stresses of this type are caused on the one hand by the pretreatment (heat treatment and hard machining) of the component and by operating conditions to which the component is exposed. For example, at the outer raceway of an inner ring and at the edges, the residual tensile stresses are further intensified by tensile stresses from the required press fit of the inner ring, for example on a shaft. If this inner ring additionally rotates at high speeds, the tensile stresses may reach a level at which the susceptibility of the inner ring to failure is significantly increased. Locally high contact pressures caused by particles which have broken off from the ceramic components and entered the rolling contact may damage the outer layer of the raceways in such a way that microcracks are formed. These microcracks then propagate to produce pitting and further, extensive damage.
The hard and sharp edges of the possible break-out locations on the rolling part made from ceramic have similar effects on the rolling parts made from steel. These break-out locations cause the steel surface to be highly stressed as a result of abrasive wear. As a result, at high rotational speeds and loads, the rate at which damage progresses may be drastically increased.
The use of ceramic components having the materials problems described above has as far as possible been avoided by suitable testing, enabling defective parts of this type to be scrapped. However, the rolling contact is endangered, in particular in bearings which are greatly influenced by the surroundings, by foreign particles which pass into the rolling contact, for example together with the lubricant. Foreign particles of this type then likewise first of all cause destruction of rolling parts made from steel, in accordance with the mechanisms outlined above.

Rolling bearing of ceramic and steel engaging parts


A mechanism is provided for detecting malicious activity in a functional unit of a data processing system. A set of activity values associated with a set of functional units and a set of thermal levels associated with the set of functional units are monitored. For a current activity value associated with the functional unit in the set of functional units, a determination is made as to whether a thermal level associated with the functional unit differs from a verified thermal level beyond a predetermined threshold. Responsive to the thermal level associated with the functional unit differing from the verified thermal level beyond the predetermined threshold, sending an indication of suspected abnormal activity associated with the given functional unit.

The present application relates generally to an improved data processing apparatus and method and more specifically to mechanisms for detecting malicious activity in one or more intellectual property (IP) functional units of an integrated circuit (IC) chip.
Since integrated circuits (ICs) are involved in critical aspects of everyday life, security of ICs is extremely important. For economic reasons, nearly all ICs are fabricated by foreign foundries and include IP functional units supplied by many third-party IP providers. In addition, ICs rely on outsourced design and test services, and use automation tools from many different vendors. Such a design and manufacturing process provides an adversary with many opportunities to insert logic to sabotage an operation of an IC used in critical applications.
An intrusion denotes a hostile modification of an IC that occurs before deployment (during design or manufacturing), providing the basis for an attack that may occur later during the normal operation of the deployed IC. Intrusions may modify the design at different stages, such as RTL (register transfer language), gate-level netlist, or GDSII (Graphic Database System II) layout. Intrusions may target the functional logic or the infrastructure logic inserted in the design to enhance the testability, the reliability, or the manufacturability of the chip. Intrusions such as focused ion-beam (FIB) circuit modifications target an already manufactured chip.
On the other hand, attacks do not require prior intrusions. For example, non-invasive tampering attacks, such as subjecting the chip to radiation or operating the chip outside its specified ranges for voltage, temperature, or frequency, can occur without any circuit modifications.

Malicious activity detection of a functional unit