An X-ray tube is enclosed in a casing containing a cooling fluid. At least one terminal part of the casing is elongated to house a high-voltage power supply device comprising a high-voltage output terminal connected to the anode and/or the cathode and low-voltage input terminals connected to low-voltage contact elements for connection to a low-voltage supply source that is located outside the casing.

1. Field of the Invention
The invention relates to X-ray units that are used to generate a beam of X-rays towards a patient's body in order to take a picture of this part by various methods such as projection on a sensitive film in standard type radiology instruments or the reconstruction of a 2D or 3D image from measurements of X-radiation made at different angles in scanner type instruments.
In present technology, an X-ray unit is constituted (FIG. i) by an X-ray tube 10 and a casing 12 filled with an insulating and cooling fluid 14 in which said X-ray tube is placed. The casing 12 is opaque to X-rays except at one place 16, the place through which the radiation (arrow 26) generated by the X-ray tube is emitted. The casing 12 is provided with the electrical terminals 18 and 34 which feed from an electrical power supply externally connected to the X-ray tube. In addition holes (not shown) provided for circulation, if necessary, of insulating and cooling fluid 14 and the filling of such fluid with casing 12.
As also shown in FIG. 1, an X-ray tube comprises a filament type cathode 20 that emits an electron beam 22 towards an anode 24 or anticathode. The anode 24 is constituted by a material such as tungsten or molybdenum which emits the beam 26 of X-rays when it is bombarded by the electron beam 22 coming from the cathode 20. To obtain a high-energy electron beam, the electrons are accelerated by an intense electrical field created between the cathode 20 and the anode 24. To this end, the anode 24 is taken to a positive potential of several tens of kilovolts with respect to the cathode. This potential may exceed hundred kilovolts and reach two hundred kilovolts.
These high electrical potentials are supplied by special cables called high-voltage cables coming from a high-voltage power supply device which is placed at some distance from the casing. This distance may reach 30 meters in certain radiology instruments.
2. Description of the Prior Art
In FIG. 1, the X-ray tube is of the rotating anode type, which implies a motor constituted by a rotor 28 fixedly joined to the anode 24 and a stator 30 fixedly joined to the envelope 32 of the X-ray tube 10, these two elements 28 and 30 having to be electrically supplied by the terminal 34.
Furthermore, since the cathode 20 is of the filament type, it should also be electrically supplied by the terminal 18.
In the example of the standard type of X-ray unit according to FIG. 1, the casing is constituted by four parts 36, 38, 40 and 42 which are assembled together in an imperviously sealed way to form an enclosed chamber in which the insulating and cooling fluid circulates through means not shown in FIG. 1. It must be noted that, in certain embodiments, the two central parts form only one part.
In this casing 12, the X-ray tube 10 is kept in position by brackets or clamps such as those referenced 44 and 46 which are fixedly joined to said casing.
FIG. 2 is a simplified electrical diagram showing how the high-voltage power supply of the X-ray tube is generally implemented.
The anode 24 and the cathode 20 are connected respectively to a high-voltage supply generator 48, placed outside the casing 12, by so-called high-voltage cables 50 and 52. Such a generator 48 comprises a high-voltage supply device 54 which supplies DC high voltages and an inverter type high-frequency converter 56, which provides the device 54 with low-voltage pulse signals having a frequency of some tens of kilohertz starting from the supply voltage E of the AC mains system.
In view of the power values needed for the operation of the X-ray tube 101 this tube is, as described further above, placed in a casing 12 containing an insulating and cooling fluid. For the same reason, the high-voltage supply device 54 is placed in another casing 58 filled with an insulating and cooling fluid.
As can be seen very schematically in FIG. 2, the high-voltage power supply device 54, which is also called a "high-voltage pack", comprises a transformer 60, having only one primary winding 62 and several secondary windings 64.sub.1 to 64.sub.n. The primary winding 60 has two input terminals E1 and E2 that are connected to two output terminals of the high-frequency converter 56.
Each of the secondary windings 64.sub.1 to 64.sub.n is connected to a rectifier and filtering circuit represented schematically by a diode D and a capacitor C, and the secondary windings are connected to each other in such a way that their output voltages get added up to obtain the desired high voltage.
A single-pole supply voltage is obtained by placing the supply conductor of the cathode (cable 52) at the potential of the ground while a symmetrical two-pole supply voltage is obtained by placing the midpoint M of the secondary circuits at the potential of the ground.
A power supply device such as this for an X-ray tube comprising high-voltage cables 50 and 52 has the following drawbacks:
two casings containing insulating and cooling liquids are used, one 12 for the X-ray tube 10 and the other 58 for the high-voltage power supply device, and the result thereof is an increased cost of the X-ray unit; PA1 the high-voltage cables 50 and 52 are specially built, and are therefore costly; PA1 the parasitic capacitance of the high-voltage cables 50 and 52 is all the greater as the cables are long, thus limiting the speed of build-up of the high voltage on the X-ray tube; PA1 as a result of the complex movements of the support of the X-ray unit, the high-voltage cables 50 and 52 are subjected to major mechanical strains that lead to problems related to reliability, safety and economy.
It is an object of the present invention, therefore, to make a high-voltage power supply device for an X-ray tube that does not have the drawbacks due to the use of special high-voltage cables.
This object is achieved through the use of a high-voltage power supply device, the dimensions of which are such that it can be placed inside the casing of the X-ray unit and can thus be in the immediate vicinity of the X-ray tube to be supplied. Thus, there is no longer any need for special high-voltage cables.
Such a high-voltage power supply device has been described in the U.S. Pat. No. 5,003,452.
To enable this power supply device to be placed in the casing of the X-ray unit, it is necessary to modify said casing and, notably, to extend it, either on the cathode side or on the anode side or on both sides. Furthermore, certain devices and protection elements have to be provided for.

X-ray unit with high-voltage power supply device integrated into the casing


The invention is a wireless microphone unit for use with a transmitter such as a CB transmitter. The microphone unit transmitted the voice signal to a receiver unit that is attached to the transmitter via a standard microphone connector that a corded microphone would be attached to. The microphone unit may be attached to a mounting unit not in use. The mounting unit and microphone unit have mating electrical connectors that charge a battery in the microphone unit when the microphone unit is mounted in the mounting unit.

Wireless microphones have been used with audio equipment to allow a performer to utilize an amplification system without having to have the microphone attached to an audio amplifier by a wire. This gives the performer freedom to move about. Examples of such wireless microphones are shown in U.S. Pat. Nos. 3,718,862, 4,344,184 and 4,815,143. The power source in each of these examples is not specified, but are presumed to be replaceable batteries.
Citizen Band (CB) radios usually have a receiver/transmit unit and a microphone attached to the receiver/transmit unit by a cable that has a connector that attaches to a mating connector on the receive/transmit unit. The cord often can become entangled, especially when the unit is mounted in a truck or automobile, and does not give the driver/CB operator freedom of using the CB radio and microphone without a cord. Cordless microphones found in the prior art are generally not suitable since extended use on a highway by a truck driver will require frequent replacement of batteries, which is not a desirable situation.


There are disclosed two types of gallium nitride LED having the pn junction. An LED of gallium nitride compound semiconductor (Al.sub.x Ga.sub.1-x N, where 0.ltoreq.x<1) comprises an n-layer; a p-layer which exhibits p-type conduction upon doping with p-type impurities and irradiation with electron rays, the p-layer joining to the n-layer; a first electrode for the n-layer so as to join to the n-layer, passing through a hole formed in the p-layer which extends from the p-layer to the n-layer; and a second electrode for the p-layer which is formed in a region which is separated by a groove formed in the p-layer so as to extend from the upper surface of the p-layer to said n-layer. An LED comprises an n-layer; an i-layer doped with p-type impurities, the i-layer joining to the n-layer; a first electrode for said n-layer so as to join to the n-layer, passing through a hole formed in the i-layer which extends from the upper surface of the i-layer to the n-layer; a p-type part in a specific region in the i-layer which is converted into p-type conduction by irradiating with electron rays, the p-type part being formed such that said first electrode is insulated and separated by the i-layer; and a second electrode for said p-type part.

1. Field of the Invention
The present invention relates to a light-emitting semiconductor device using gallium nitride group compound which emits a light in the region from blue to ultraviolet, and also to a process for producing the same.
2. Description of the Prior Art
It is known that GaN compound semiconductor can be made into a light-emitting semiconductor device, such as a light-emitting diode (LED), which emits a blue light.
The GaN compound semiconductor attracts attention because of its high light-emitting efficiency resulting from a direct transition and of its ability to emit a blue light which is one of the three primary colors.
The light-emitting diode of GaN compound semiconductor is composed of a sapphire substrate, an n-layer and an i-layer grown thereon. The n-layer of the GaN compound semiconductor with n-type conduction is directly grown on the surface of the sapphire substrate or grown on a buffer layer of aluminum nitride formed on the sapphire substrate. The i-layer of semi-insulating (i-type) GaN compound semiconductor is doped with p-type impurities. (See Japanese Patent Laid-open Nos. 119196/1987 and 188977/1988.)
The voltage for driving this light-emitting diode, however, is high. Consequently, there is room for improvement.
Another disadvantage of the gallium nitride compound semiconductor is that it does not become p-type but remains i-type (semi-insulator) even though it is doped with p-type impurities.
As the results of extensive studies, the present inventors succeeded in producing a p-type gallium nitride compound semiconductor. This led to the creation of a pn junction that emits a blue light efficiently.
The light-emitting diode comprising the pn junction, however, presents a problem associated with insulating the electrode for a lower layer from an upper layer in case that the electrode for the lower layer is formed through the upper layer to get the electrode on the upper layer, because the p-layer and n-layer are electrically conductive.

Light-emitting semiconductor device using gallium nitride group compound

Research Development Corporation of Japan


While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

A wheel usually has a rim ring with a rim well, which is defined by an inner wheel flange and an outer wheel flange. The inner wheel flange and the outer wheel flange circumferentially enclose the tire, guide same and seal it airtightly by the tire walls being sealingly supported on the wheel flanges based on the internal pressure in the tire. A wheel spider or a rim disk, which establishes the connection with the axle, is arranged as a carrier element for the rim in the interior of the rim.
Many two-part wheel solutions for the manufacture of automobiles are known from the state of the art. Such two-part wheels are used especially for trucks in order to facilitate tire change. The wheels are designed for this such that the two wheel parts are detachable from each other. Each of the two wheel flanges is arranged on a different part of the two-part wheel.
Another reason for designing wheels as two-part wheels lies in the aesthetic requirements imposed on these. Thus, it is occasionally desirable to have the possibility of replacing the wheel spider with a wheel spider of a different design. Such an object is accomplished, for example, by DE 8526012U1, which proposes a rim ring with rim well as well as a wheel spider arranged detachably on this. The wheel spider is fastened to the rim ring by the spider ends extending behind corresponding counterpieces on the rim ring in the manner of a bayonet catch and are fixed under these with bolts. Another embodiment describes that the wheel may be a two-part wheel, wherein each part has a wheel flange and wherein the two parts of the wheel are connected by said bayonet catch-like coupling.
The solution according to U.S. Pat. No. 6,726,292 B1, in which two wheel parts made of fiber composite, each of which has a wheel flange and a part of the wheel spider, mesh with one another with ideal (complementary) shape on the sides facing one another, serves the purpose of reducing the weight. A number of recesses on the inner wheel part is located opposite an ideally shaped number of teeth on the outer wheel part. The five spokes of the wheel spider have a rectangular cross section and are hollow and are formed by the base, which is provided by the inner wheel part, and a trilateral counterpiece, which is provided by the outer wheel part. The two wheel parts are held together by bolt connections, as well as by the wheel retaining nuts, which hold both wheel parts.
WO 1997/13647 A1 describes a two-part wheel, in which each wheel part likewise has a wheel flange and a part of the wheel spider, for an especially cost-effective vehicle design. The two wheel parts have contact surfaces facing each other, which have ideally shaped elevations and depressions meshing with one another. The two wheel parts are held together by click and bonded connection as well as by rivets. Moreover, the lug nuts also hold the two parts together in the mounted state. The wheel is preferably made of fiber-reinforced plastic and is said to be especially lightweight. The two wheel parts are bonded to one another over the entire surface in the mounted state. The rim well is formed by a projecting edge of the inner wheel part, which meshes with a corresponding groove of the outer wheel part due to click connection.
Wheels are subject to different, high stresses. These stresses occur to a lesser extent during the simple acceleration or braking operations or during the typical rolling operation and they rather occur when the wheels meet obstacles. This is especially critical when the wheels are not stressed indirectly via the tires but are stressed directly laterally. Such stresses occur, e.g., when hitting curbstones. The prior-art wheel designs can respond to these stresses only poorly. Furthermore, it is problematic to design the complex shape of an automobile wheel in a cost-effective and effective manner.


The invention provides a method for determining the orientation of a wellbore relative to stress fields within a formation through analysis of pressure climb data during a test fracturing operation. The test fracturing operation may be formed in a plurality of wells having a known angular relation to one another in a given formation. A known angular or azimuthal relationship between the wells may be correlated with the derivative of the pressure decline proximate the relief in pressure area to define maximum azimuthal stress field and a minimum azimuthal stress field in the formation.

The present invention relates generally to the determination of fracture orientation relative to a wellbore and relative to formation stress fields, and more specifically relates to such methods performed in response to analysis of pressures observed during a fracturing operation.
The use of test fracturing operations to determine reservoir or formation characteristics prior to the performance of a full scale fracturing operation is well-known. For example, the evaluation of a formation through use of a test fracturing operation performed through use of a fracturing fluid without proppant is well-known. Exemplary procedures of this type are those normally referred to in the industry as "minifrac" or "microfrac" operations.
As an example of a microfrac operation, during the microfrac operation a short interval of a wellbore is pressurized until a "breakdown" of the formation occurs. The formation will breakdown when the pressure at the formation reaches a "breakdown pressure," i.e., that pressure at which the tangential stress changes from compression into tension and reaches the tensile strength of the formation. At this point, the formation will yield to the stress, and a tensile fracture will be created. As pressure is monitored during the pressurization of the wellbore interval approaching the breakdown pressure, the characteristics of the monitored pressure curve will depend upon the fluid injection rate and the fluid leak-off rate. As pressure continues to be applied, the fracture will extend, and the extension pressure may either increase or decrease, depending upon any height restriction on fracture propagation and fluid leak-off. At some point, the injection will be ceased, and an instantaneous shut-in pressure will be recorded. As is known to the industry, this parameter will yield information regarding frictional pressure during the injection operation. Pressure decline after shut-in will be monitored, and the closure pressure will be determined. The closure pressure is that pressure at which the created fracture will close. This pressure will be equivalent to the minimum horizontal stress within the formation. If the shut-in is continued for an extended period, the formation will eventually reach an equilibrium pressure, at which time the pressure will be equal to the initial reservoir pressure.
Conventional minifrac and microfrac pressure analysis operations have not been capable of providing an indication of the direction of the fracture from the wellbore relative to stress fields existing in the formation. This information is highly desirable, as it will provide information useful, for example, in the design of future perforating operations and the design of full scale fracturing treatments for the wellbore. Additionally, the determination of a direction of fracture propagation, particularly in highly deviated or generally horizontal wells, may be particularly useful.
Accordingly, the present invention provides a new method and apparatus for utilizing observed pressure data during a test fracturing operation to determine the fracture direction relative to stress fields in the formation surrounding the wellbore. The method and apparatus of the present invention may also be particularly useful in deviated or horizontal wells to determine the direction of the fracture relative to the wellbore direction.

Method and apparatus for determining orientation of a wellbore relative to formation stress fields


An object of the present invention is to provide an R—Fe—B based sintered magnet having on a surface thereof a chemical conversion film with higher corrosion resistance than a conventional chemical conversion film such as a phosphate film, and a method for producing the same. The corrosion-resistant magnet of the present invention as a means for achieving the object is characterized by comprising a chemical conversion film containing at least Zr, Nd, fluorine, and oxygen as constituent elements and not containing phosphorus directly on a surface of an R—Fe—B based sintered magnet, wherein R is a rare-earth element including at least Nd.

Nowadays, R—Fe—B based sintered magnets represented by Nd—Fe—B based sintered magnets have been used in various fields for their high magnetic characteristics. However, an R—Fe—B based sintered magnet contains a highly reactive rare-earth metal: R, and thus is susceptible to oxidization and corrosion in air. Therefore, when such a magnet is used without a surface treatment, corrosion proceeds from the surface due to the presence of small amounts of acids, alkalis, water, etc., whereby rust occurs, causing deterioration or fluctuation in the magnetic characteristics. Further, when such a rusted magnet is incorporated into a device such as a magnetic circuit, the rust may be dispersed and contaminate peripheral parts.
Various methods are known for imparting corrosion resistance to an R—Fe—B based sintered magnet. One of them is a method in which a surface of the magnet is subjected to chemical conversion treatment to form a chemical conversion film. For example, Patent Document 1 describes a method in which a phosphate film is formed as a chemical conversion film on the magnet surface. This method has been widely employed as a simple rust-prevention method for easily imparting necessary corrosion resistance to a magnet.    Patent Document 1: JP-B-4-22008

Corrosion-resistant magnet and method for producing the same


A bias element for use in a magnetomechanical EAS marker is magnetized to saturation. Then the magnetic charge in the bias element is redistributed by applying to the bias element a magnetic field having an AC ringdown characteristic. The redistribution of magnetic charge improves the stability of the bias element, so that the marker incorporating the bias element is less likely to have its resonant frequency shifted by exposure to a stray magnetic field.

It is well known to provide electronic article surveillance systems to prevent or deter theft of merchandise from retail establishments. In a typical system, markers designed to interact with an electromagnetic field placed at the store exit are secured to articles of merchandise. If a marker is brought into the field or "interrogation zone", the presence of the marker is detected and an alarm is generated. Some markers of this type are intended to be removed at the checkout counter upon payment for the merchandise. Other types of marker remain attached to the merchandise but are deactivated upon checkout by a deactivation device which changes a magnetic characteristic of the marker so that the marker will no longer be detectable at the interrogation zone.
One type of EAS system employs magnetomechanical markers that include a magnetostrictive element. U.S. Pat. No. 4,510,489, issued to Anderson et al., discloses a marker formed of a ribbon-shaped length of a magnetostrictive amorphous material contained in an elongated housing in proximity to a biasing magnetic element. The magnetostrictive element is fabricated such that it is resonant at a predetermined frequency when the bias element has been magnetized to a certain level. At the interrogation zone, a suitable oscillator provides an AC magnetic field at the predetermined frequency, and the marker mechanically resonates at this frequency upon exposure to the field when the bias element has been magnetized to a certain level. The interrogation field is provided in pulses or bursts. A marker present in the interrogation field is excited by each burst, and after each burst is over, the marker undergoes a damped mechanical oscillation. The resulting signal radiated by the marker is detected by detecting circuitry which is synchronized with the interrogation circuit and arranged to be active during the quiet periods after bursts. EAS systems of the above-described pulsed-field magnetomechanical type are sold by the assignee of this application under the brand name "Ultra*Max" and are in widespread use. (The disclosure of the Anderson et al. patent is incorporated herein by reference.)
In magnetomechanical markers of the type described above, the bias element may be utilized as a control element to switch the marker between activated and deactivated states. Typically, the bias element is formed of a semi-hard magnetic material, such as the material designated as "SemiVac 90", which is available from Vacuumschmelze, Hanau, Germany. Conventional bias elements are in the form of a ribbon-shaped length of the semi-hard material. To place the marker in the activated condition, the bias element is magnetized substantially to saturation with the polarity of magnetization parallel to the length extent of the bias element. To deactivate the marker, the magnetic state of the bias element is substantially changed, as, for example, by degaussing the bias element by applying thereto an AC magnetic field at a level higher than the coercivity H.sub.c of the material. When the bias element has been degaussed, it no longer provides the bias field required to cause the magnetostrictive element (also known as the "active element") to oscillate at the predetermined operating frequency of the EAS system. In addition, the level of the signal output by the magnetostrictive element is greatly reduced in the absence of the bias field. Consequently, when the bias element has been degaussed, the magnetostrictive element does not respond to the interrogation signal so as to produce a signal that can be detected by the detection circuitry of the EAS system.
Co-pending patent application Ser. No. 08/697,629, filed Aug. 28, 1996 (which has a common assignee and a common inventor with the present application), discloses an improved magnetomechanical EAS marker in which the bias element is formed of a semi-hard magnetic material which has a lower coercivity than conventional materials for bias elements. When such low-coercivity bias elements are used, it is possible to deactivate markers by applying a much lower level AC field than was required with conventional, higher-coercivity bias elements. This, in turn, allows for a reduction in the power level at which deactivation equipment is operated. Also, or alternatively, the markers can be reliably deactivated at a greater distance from the deactivation device than was feasible with higher-coercivity bias elements. Moreover, with the lower power level required for deactivation of the low-coercivity bias elements, it becomes feasible to operate deactivation equipment in a continuous wave mode, rather than in triggered pulses as has been the practice in conventional deactivation equipment.
For the reasons given above, it is desirable that magnetomechanical EAS markers be deactivatable with a rather low level AC field. However, it is a competing desirable characteristic of EAS markers that the same be "stable". That is, when a marker is in an activated condition, its response characteristics should not be adversely affected by exposure to stray magnetic fields that may be encountered during shipment, handling or storage of the marker. It will be understood that if the coercivity of the bias element is too low, the risk of unintentional deactivation by exposure to stray fields may become excessive.
The inevitable trade-off between stability and low deactivation field level can be ameliorated if the bias element exhibits "abruptness". That is, it is desirable that the bias element exhibit stability over a range of applied AC fields from zero up to a threshold level, and that the bias element exhibit a rather sharp or abrupt decrease in magnetization in response to exposure to an AC field having a peak amplitude above the threshold level.

Redistributing magnetic charge in bias element for magnetomechanical EAS marker


A method for improving signal levels between capacitively-coupled chips in proximity communication (PxC) includes depositing a high permittivity dielectric material layer over a signal pad of a first chip, and placing a second chip in close proximity to the first chip such that faces of the signal pads align to enable for capacitive signal coupling. The high permittivity dielectric material layer that fills at least a portion of a gap between the first chip and the second chip, and improves capacitive coupling between signal pads of the first chip and the second chip by providing for an increased permittivity in the gap between the first chip and the second chip. The increased permittivity ensures that electric fields are substantially confined to a space between the signal pad of the first chip and the signal pad of the second chip.

1. Field of the Invention
The present invention relates generally to a method for increasing signal coupling between pads of chips engaged in capacitive proximity communication (PxC). More specifically, the present invention relates to a method for increasing signal coupling, where a high permittivity dielectric material is directly deposited atop the pads to enable confinement of electric fields within pad gaps of the chips.
2. Background Art
With scaling of processor technology to future generational requirements, the pressing need for increased serial data rate over many communication channels to off-chip memory is not eased by the inability of electrical signaling to drive off-chip structures efficiently due to mismatch between on-chip and off-chip bandwidths. Thus, the ability of processors to exploit advancements in computational power, clock frequency, transistor count, multi-core architectures and the like is limited. One way to circumvent the aforementioned limitation is to employ PxC as a means to signal between processor and memory.
PxC is a form of wireless communication between chips, with the possible chip-to-chip coupling being capacitive, inductive or optical. Capacitive coupling may be employed to provide a high-bandwidth and high density channel between two chips placed face-to-face and extremely close to each other such that the transmitter circuits of one chip align with the receiver circuits of the other. An input/output (I/O) technology using the capacitive coupling of PxC can scale with on-chip features unlike traditional area ball bonds, leading to a largely improved I/O density. Thus, PxC with capacitive coupling offers the advantages of a hundred-fold increase in bandwidth density with a simultaneous three-fold reduction of on-chip power dissipation over traditional off-chip I/O signaling, thereby aiding utility in applications with power hungry, I/O limited multi-chip systems.
FIG. 1 shows two chips (110, 120) placed close to each other in a capacitively coupled PxC mode. Each chip includes transmitter (114, 122) and receiver circuits (112, 124), where a transmitter circuit of one chip (114, 122) communicates with the receiver circuit (112, 124) of the other chip by way of a metal plate on one chip and the metal plate on the other chip forming a capacitor. The metal plates of the transmitter circuit (114, 122) are depicted as shaded rectangles and the metal plates of the receiver circuit (112, 124) are depicted as non-shaded rectangles. A metal plate on the transmitter side is driven by the transmitter circuit (114, 122) and a metal plate on the receiver side drives the receiver circuit (112, 124).
When the two chips (110, 120) are moved close to each other, the surfaces of the dielectric and passivation layer touch each other, thereby allowing for excellent capacitive coupling between the metal plates due to their proximity. Also, the sizes of the transmitter and receiver structures may be reduced, allowing for reduced parasitic capacitances and huge power savings. The need for electrostatic discharge (ESD) protection devices is dispensed with as the metal plates lie under the passivation layer. This contributes to an additional reduction in capacitance and power consumption.
FIG. 2 shows a typical cross-section of transmitter 212 and receiver 222 pads of two chips (210, 220) involved in capacitive PxC. Communication between the transmitter 212 and receiver 222 pads is affected by three capacitances in positive and negative ways. The desired capacitance, i.e., the signal capacitance Cs, is the capacitance between the transmitter 212 and the receiver 222 pads. The unwanted capacitance due to coupling between adjacent transmitter 212 and receiver 222 pads is the noise capacitance Cn. As shown in FIG. 2, guard rings 224 may be provided between receiver 222 pads to suppress crosstalk between individual pads. However, an unwanted parasitic capacitance Cp may have to be factored into received signal calculations. This parasitic capacitance Cp may arise due to coupling between receiver 222 pads and guard rings 224, coupling between receiver 222/transmitter 212 pads and the ground plane, and/or intrinsic capacitance. Thus, these capacitances depend on inter-pad distance and inter-chip distance. Conservation of charge deems that the received signal, Vr, is dependent on the capacitances, and may be obtained from example Equation (1) as follows.(Cs+Cn+Cp)Vr=VsCs,  (1)
where Vs is the source signal. The received signal, Vr, as a function of capacitances, may, therefore, be expressed as:
                              V          r                =                                            C              s                                                  V              s                                            (                                          C                s                            +                              C                n                            +                              C                p                                      )                                              (        2        )
Assuming equal dimensions w×l of two plates, equal plate thickness of t, and a separation between plates d, the capacitance C between two plates may be expressed as:
                              C          =                                                    ɛ                d                                                          (                                  w                  -                                      t                    2                                                  )                                                          (                                  l                  -                                      t                    2                                                  )                                      +                                          πɛ                                                  (                                      l                    +                    w                                    )                                                                          f                                                  (                                                            d                      2                                        ,                    t                                    )                                                                    ,                            (        3        )
where ∈=∈0∈r is the permittivity of the medium between the two plates, ∈0 being the permittivity of free space and ∈r being the dielectric constant of the medium between the two plates, and f(d,t) is given by:
                              f                                (                          d              ,              t                        )                          =                  1                      [                          ln                                            (                                  1                  +                                                            2                                            d                                        t                                    +                                                                                2                                                    d                                                t                                                                                (                                                                                2                                                            d                                                        t                                                    +                          2                                                )                                                                                )                                      ]                                              (        4        )
Using the method of images, Equation (3) is obtained by modeling the fringing fields of a rectangular micro-strip line over a ground plane as field lines due to a ground plane between two plates. Equation (3) does not account for the capacitance due to the four corners of the plates, which however is very small, but accounts for both the fringing fields and the parallel plate component. Equation (3) may be used to model the capacitance between transmitter 212 and receiver 222 pads, or any two finite pads separated by a small distance.
The crosstalk problem that arises in PxC may be due to fringing fields emanating from the length and width of the transmitter 212 pad not being coupled to the receiver 222 pad above and below the transmitter 212 pad (a receiver 222 pad above is not shown in FIG. 2). The crosstalk capacitance Cct1 may be modeled by subtracting from the capacitance when the receiver 222 pad is infinite the capacitance when the receiver 222 pad is of the same dimensions as the transmitter 212 pad, and may be expressed as:
                              C          ct                =                              πɛ                                      (                              l                +                w                            )                                                      (                                          f                                                  (                                      d                    ,                    t                                    )                                            -                              0.5                                                  f                                                        (                                                                  d                        2                                            ,                      t                                        )                                                                        )                                              (        5        )
The crosstalk problem may also have a contribution from two adjacent receiver 222 pads forming a parallel plate capacitor between each other, where the thickness of the pad contributes mainly to the capacitance Cct2, which may be expressed as:
                                          C                          ct                                                                                2                                =                      ɛ                                      (                                                tl                                      (                                          p                      -                      w                                        )                                                  +                                  Af                                                        (                                                                                (                                                      p                            -                            w                                                    )                                                2                                            ,                      w                                        )                                                  +                                  1.47                                    l                                            )                                      ,                            (        6        )
where p is the center to center distance between adjacent pads, and A may be expressed as:
                    A        =                  0.5                                                                          π                                      (                              t                +                l                            )                                                      (                          1              -                              0.0543                                                  w                                      (                                          p                      -                      w                                        )                                                                        )                                              (        7        )
Typically, field lines from receiver 222 pads are not only coupled to adjacent receiver 222 pads but also coupled to the transmitter 212 plates below (not shown in FIG. 2). Therefore, the capacitance Cct2 reduces by a fraction, and may be expressed as:
                              C                      ct                                                                          2                          =                              ɛ                                      (                              d                                  p                  -                  w                  +                  d                                            )                                                      (                                          tl                                  (                                      p                    -                    w                                    )                                            +                              Af                                                  (                                                                                (                                                  p                          -                          w                                                )                                            2                                        ,                    w                                    )                                            +                              1.47                                l                                      )                                              (        8        )
Misalignment is another problem in PxC. FIG. 3 shows a one-dimensional misalignment between two plates 310 and 320 in the direction of the width w. w1 is the width of receiver 310 plate that overlaps with a transmitter plate 320, whose width of non-overlap is w2. Thus, w can be expressed as:w=w1+w2  (9)
The capacitance Cma between two misaligned parallel plates 310 and 320 may be approximately expressed as:
                              C          ma                =                  ɛ                                (                                                                                w                    1                                                      l                                d                            +                              π                                                                                w                  1                                                                  f                                                        (                                                                  d                        2                                            ,                      t                                        )                                                              +                              π                                                                                lf                                                        (                                                                                0.25                                                                                (                                                                                d                                2                                                            +                                                              w                                2                                2                                                                                )                                                                                ,                      t                                        )                                                                        )                                              (        10        )
With the rapid changing status quo of Silicon technology, PxC requires chip separation on the order of 10 microns, which would shrink to smaller levels with future generation technology. In order to ensure high fidelity transmission of data streams with very low power and ultra-high density, gap requirements of a few microns and even sub-micron gaps may be the order of the day. Typical low-cost chip manufacturing processes achieve tolerances that are no better than a few mils (1 mil=25.4 microns).
FIG. 4 shows the plot of signal levels in flinging fields that are potential contributors to crosstalk in a dense PxC array as a function of chip separation for different pad dimensions. The x-axis denotes chip separation 410 in microns, and the y-axis signal levels 420 expressed as a percentage. Three different pad dimensions are chosen, viz. 1 micron pads 430, 10 micron pads 440, and 50 micron pads 450. FIG. 4 clearly demonstrates that when pad sizes are reduced to convenience high-density packaging, the signal levels coupled from pad to pad decrease with increase in chip separation 410. Alternatively, signal levels 420 in fringe fields increase with increase in chip separation 410.

Dielectric enhancements to chip-to-chip capacitive proximity communication


An opening and closing system permits a drawer to be operated by pressing on a front panel of the drawer (e.g., in a hands-free manner). By way of example, the system includes a first sub-assembly coupled to the drawer and a second sub-assembly coupled to a drawer frame. A linear spring provides a tensioning force for operation of the drawer. The first sub-assembly includes a first pivot biasly coupled to the drawer, a fixed-length arm having a first end fixed to the first pivot and a second end coupled to a roller. The second sub-assembly includes first and second guide arms coupled to a second pivot, the first guide arm having an upper surface for engaging the roller when the drawer is being closed, the second guide arm having an arcuate-shaped region sized to receive at least a portion of the roller after the drawer is closed.

Conventional drawer slide systems generally include a drawer having tracks located along the sides of the drawer. The tracks translate or glide on rollers coupled to a cabinet or other frame where the drawer may be installed. By way of example, one type of conventional drawer slide system is described in U.S. Pat. No. 3,937,531 while a cam-type drawer glide system is described in U.S. Pat. No. 1,391,004.


A universal briefcase protector for use with briefcases of various sizes and shapes. The briefcase protector of the present invention protects both the body of the briefcase as well as the handles. Additionally, the briefcase protector allow for normal carrying of the briefcase even when the protector is employed.

The need for protector to protect the outer surfaces of briefcases and luggage has long been recognized. By their very nature, briefcases and other such cases are subject to damage from physical abrasions or scratches, or from rain or snow. Such damage can not only produce unsightly marks, but can in fact ruin the case. While briefcases are very expensive, briefcase protectors can easily be replaced at a relatively small expense if damaged. Therefore, the prior art shows several attempts to create luggage protectors for such purposes.
U.S. Pat. No. 2,647,595 (Meyers) issued Aug. 4, 1953 discloses a supplementary protector to protect luggage. This patent relates to a luggage protector which is slipped over the top of luggage and secured beneath the luggage by elastic strips. The patent does not address means for covering the handle of the luggage.
U.S. Pat. No. 2,693,295 (Amick) issued Nov. 2, 1954 relates to a luggage cover. Amick teaches a suitcase cover which is folded around a suitcase through the use of flaps and snap fasteners. The Amick luggage cover does not protect the suitcase handle.
U.S. Pat. No. 2,711,234 (Rubens) issued Jun. 1, 1955 relates to an adjustable luggage cover. This patent discloses a cover that adjusts through the use of elastic strands to fit over various sizes of luggage. The cover described by the Rubens patent does not protect the handle of the luggage.
U.S. Pat. No. 2,732,046 (Smallberg) issued Jan. 24, 1956 discloses luggage covers for rigid walled luggage. This patent teaches the use of elastic portions which provide a snug fit over such luggage and allow for slight variations in the size of the luggage.
U.S. Pat. No. 2,724,467 (Jaffe) issued Nov. 22, 1955 relates to a luggage cover. The luggage cover disclosed in the Jaffe patent utilizes fastening means surrounding the outside of the cover to close the protected luggage.
U.S. Pat. No. 3,901,360 (Cook) issued Aug. 26, 1975 discloses a luggage protector. This patent teaches a unitary protector having a slit opening for the handle and having a single closure means extending all the way around the body of the luggage protector.
In each of these references, the protector is designed in such a way as to leave the handle of the briefcase exposed. Furthermore, the opening through which the handle protrudes is typically uncovered, allowing water or other materials to leak into the protector. A need therefore exists for a protector that provides protection not only for the main storage portion of the briefcase, but also for the handle, while allowing the handle to be grasped in a normal manner. Such a protector should be designed so as to adapt quickly and easily to fit over a variety of sizes and shapes of briefcases.
It is therefore an object of the present invention to provide a briefcase protector which protects not only the baggage portion of the briefcase, but also the handle portion.
A further object of the present invention is to provide a briefcase protector that protects the handle of a briefcase in such a way as to allow the briefcase to be grasped and carried in a normal manner.
Another object of the present invention is to provide a briefcase protector that can be quickly and easily fastened or removed.
It is another object of the present invention to provide a briefcase protector which may be used in conjunction with briefcases of various sizes and shapes.
It is still another object of the present invention to provide a briefcase protector which is small and easily transportable so that when it is not in use, it can be carried inside the briefcase. These and other objects of the present invention will be made clear through the following detailed description of the preferred embodiment.

Briefcase protector with a handle cover portion


An image of a workpiece is taken by a CCD camera, which includes a view field covering a supply range of the workpiece, and is transmitted to an image processor to detect the position and posture of the workpiece. A robot controller controls a robot to approach a position from another position based on the result of the detection. Then, a measurement using a laser sensor is started. Scanning laser beams projected from an emitter are detected by a light detector and the detected data are analyzed by the image processor. When the robot reaches a third position, the measurement is terminated. The laser sensor may be of a split-light-projection type. For the approaching movement, the image taken by the camera is displayed on a display device to perform a jogfeed of the robot on the screen.

In assembling and machining operations of production lines, it has been a popular practice to detect of a position and a shape of each of various objects using various kinds of sensors. Generally, a sensor for taking a two-dimensional image (e.g., a visual sensor using a CCD camera) is effective in measuring the general position of an object. To the contrary, a laser sensor is effective in measuring a position and a shape of a local part of the object.
The laser sensor is easy to mount on the arm end of a robot and in the case where the output of the laser sensor is fetched into the robot controller, the detailed position and shape of a local part of the object can be measured accurately in real time by projecting a laser beam onto the object from a very nearby position and to use the measured data in correcting the position of the robot.
Accordingly, the robot system having a laser sensor is very popular in the field of an arc-welding robot, a sealing robot and a measuring robot, etc.
The laser sensors are chiefly divided into two types, a spot-light-projecting type and a slit-light-projecting type. In the laser sensor of either type, a spot light beam or slit light beam has to be projected accurately on a surface of the object. As long as the object is positioned in a fixed position with some degree of precision, it is easy to quickly realize such a status that a spot beam or a slit beam is projected on the object, by previously teaching a nearby position of the fixed position, as an approach position to the robot.
However, the object would be positioned often with no precision or less reliable precision, depending on the application. In such event, the object has to be searched using a spot or slit light beam of the laser sensor as a probe while moving the robot along a suitable taught path, and if the work could not found out, it would be impossible to start the main measuring (e.g., the shape measuring) using the laser sensor.
Since the laser sensor is inherently unsuitable for large-area measuring, it would take time to search the object and subsequently to approach to the object. On some occasions reliable searching itself would be difficult. Even if it could be successful in finding the object, this fact might not be useful directly in correcting the robot position. For example, it would not always easy to discriminate a position and a direction (e.g., the position of a start point of welding line and the direction of extension) specified according to the posture of the object, from the laser sensor output obtained for the object in unknown posture.

Multiple-sensor robot system for obtaining two-dimensional image and three-dimensional position information


A non-contact data carrier includes a battery, an electric-supply circuit for rectifying a received carrier signal and generating power, and an electric-supply switching circuit for comparing the voltage of the battery and the voltage generated by the electric-supply circuit and selecting either one of the voltages. When the battery can supply power, long-distance communication can be performed by supplying power from the battery. In case of battery exhaustion, power is supplied from the electric-supply circuit which receives a stronger carrier signal by using the non-contact IC card in the proximity of a question unit and rectifies the carrier signal, so that the function of the non-contact data carrier is maintained.

The present invention relates to a non-contact data carrier system, for communicating by use of a radio wave, for uses for verification of various IDs, financial trading and control of a door lock of a car, and a non-contact data carrier used for the same.
A non-contact IC card as an example of the non-contact data carrier has a convenience that it is unnecessary to insert the non-contact IC card into a slot of a reader/writer as well as features of normal IC cards having a large storage capacity and a high-degree security function. Therefore, the non-contact IC card is a product of which a great market can be expected not only as a commuter ticket of public transportation and a ticket for a ski lift but also as a room entry/exit card for opening or closing a door and a card for electronic money. Such a non-contact IC card performs information transmission and reception with a question unit by use of a medium such as a radio wave. Power necessary for operation of a control circuit and a memory of the non-contact IC card is obtained from a battery incorporated in the card or by rectifying, by a radio wave transmitted from the question unit, an induced current generated due to mutual induction of a coil provided in the non-contact IC card.
FIG. 7 is a block diagram showing the configuration of a conventional non-contact IC card which operates on power supplied from a battery 29. A main circuit unit 13 of the non-contact IC card comprises a reset circuit 5, a demodulation circuit 6, a modulation circuit 7 and a memory 12. The main circuit unit 13 further comprises a control circuit 11 for controlling the above-mentioned circuits and performing reading from and writing to the memory 12 in accordance with the contents of a signal transmitted from a question unit (not shown). A transmitter-receiver 1 comprising an antenna and a tuning circuit (both are not shown) receives a radio signal transmitted from the question unit. A carrier signal detection circuit 3 compares the level of the received signal and a reference level preset in the carrier signal detection circuit 3. When the level of the received signal is higher than the reference level, a switching circuit 8 goes into on state, so that power is supplied from a battery 29 to the main circuit unit 13. As a result, the non-contact IC card operates. When the level of the received signal is not higher than the reference level, the non-contact IC card does not operate and goes into sleep state which is the state only to receive and detect a signal which will be again transmitted from the question unit.
In the non-contact IC card having the switching circuit 8, power is supplied to the circuit components only when a carrier signal from the question unit is detected. Therefore, when no carrier signal is transmitted from the question unit, that is, when information transmission and reception is not performed between the non-contact IC card and the question unit, only the carrier signal detection circuit 3 consumes power, so that power consumption is reduced.
The above-mentioned non-contact IC card uses an internal battery 29 as the power source and the power necessary for operation of the non-contact IC card is supplied from the battery 29. On the other hand, in a non-contact IC card which uses induced electromotive force generated at a coil incorporated in the non-contact IC card, rectified induced-electromotive-force is stored and the stored force is used for operation of the non-contact IC card. Therefore, the induced electromotive force generated in the coil decreases corresponding to increase of the distance between the non-contact IC card and the question unit. In order to prevent the induced electromotive force from decreasing, it is necessary to use the non-contact IC card in the proximity of the question unit at the time of communication.
That is, in the latter non-contact IC card, the longer the distance between the question unit and the non-contact card is, the lower the value of the induced electromotive force is, so that it is difficult to ensure the power necessary for operation. On the contrary, in the former non-contact IC card, since stable power is supplied from the battery 29, long-distance communication can be performed.
Generally, the convenience of the non-contact IC card is influenced by a communication-possible distance between the question unit and the non-contact IC card. By increasing the communication distance between the non-contact IC card and the question unit, the non-contact IC card can be used at a position remote from the question unit, and thus the convenience is improved. The non-contact IC card in which power is supplied from a battery is excellent in convenience because a long communication distance can be ensured compared with the non-contact IC card using the induced electromotive force.
However, since the battery is required for operation, the non-contact IC card becomes inoperable when the capacity of the battery is low, that is, when the battery is exhausted. As described above, when the non-contact IC card is in sleep state, only the carrier signal detection circuit 3 is actuated for detecting a signal from the question unit. Therefore the power consumption is reduced. However, slight power is still consumed. Consequently, the battery is exhausted when the non-contact IC card is used for a long time. Normally, the non-contact IC card does not have means for displaying the remaining capacity of the internal battery, so that it is impossible for the user of the non-contact IC card to predict battery exhaustion. For this reason, the non-contact IC card is hardly used for important work or for recording important data.
When the battery is exhausted, the use of the non-contact IC card cannot be continued unless a replacement battery is at hand. Even if a battery is available, a tool such as a screwdriver is necessary for battery replacement, so that it is very difficult to replace the battery in a short time to use again the non-contact IC card.
An object of the present invention is to prevent a trouble caused by battery exhaustion of the non-contact IC card while maintaining the convenience that long-distance communication can be performed.
Another example of use of a conventional non-contact data carrier will be described hereinafter.
Conventionally, a door lock of a car employs a system for locking or unlocking the door by inserting a key into a key cylinder provided at the door and turning the key either leftward or rightward. In recent years, in order to simplify such locking or unlocking by use of a key, a wireless door lock system, namely, so-called keyless entry system has become widespread for locking and unlocking not only a door but also a trunk lid without the use of the key. In the keyless entry system, a locking or unlocking instruction is transmitted to a locking device for the door or the trunk lid from a position remote from it. The locking or unlocking instruction is given by use of light or a radio wave. For example, by pressing a push button 31 provided on a key terminal 30 as shown in FIG. 8, a key ID number is transmitted to the locking device of a vehicle. The key ID number is verified by a terminal device mounted in the vehicle. As a result of the verification, when the key ID number coincides with the key ID number of the vehicle, door locking or unlocking is performed. According to this configuration, even at nighttime or in an indoor parking lot where the keyhole of the key cylinder is not easily found because it is dark, door locking or unlocking can be easily performed without the key being inserted into the key cylinder. Recently, many vehicles have employed this system for the purpose of increasing their added values.
In this keyless entry system, it is necessary to take out the key terminal 30 and transmit the key ID number by pressing the push button 31 toward the vehicle every time door locking or unlocking is performed. Although it is unnecessary to look for the keyhole in order to insert the key into the key cylinder, when the user""s both hands are taken up by baggage or when the user puts up an umbrella at the time of rain, it is necessary for the user to put down the baggage or the umbrella before taking out the key terminal 30 and pressing the push button 31 to perform key locking or unlocking. Thus, the conventional keyless entry system is still inconvenient.
Data of the key ID number used in the above-described system is transmitted from the key terminal to the vehicle-mounted terminal device as a coded binary signal. Therefore, the key ID number data can be fraudulently obtained by disassembling the key terminal and analyzing it in detail. Further, the coded signal, which is comparatively simple, can be read by a cryptoanalysis apparatus. The key ID number can also be obtained by replicating the signal. The terminal device controlling door lock condition determines that an access is made by an authorized key terminal when the received key ID number coincides with the key ID number of the vehicle, and locking or unlocking is performed. It is difficult to adopt a configuration for denying an access from a key terminal transmitting a fraudulently obtained ID number. Thus, the conventional keyless entry system is defective also in security.
The key terminal incorporates a battery and uses it as the power source when transmitting the key ID number data. When the battery capacity is low, that is, when the battery is exhausted, the Key ID number data cannot be transmitted from the key terminal. Under such a state, door locking or unlocking by the keyless entry system cannot be performed, so that it is necessary to insert the key into the key cylinder to lock or unlock in a manner similar to the conventional door lock.
The present invention is intended for solving the above-described conventional problems, and provides a non-contact data carrier system applied to control of a door lock of a car in which security and convenience of the keyless entry system are maintained without use of a key to lock or unlock the door.
A non-contact data carrier of the present invention comprises transmission-reception means for receiving a carrier signal from a question unit and transmitting transmission data to the question unit, carrier signal detection means for detecting the carrier signal, a demodulation circuit for demodulating the carrier signal, a modulation circuit for modulating the transmission data to be transmitted to the question unit, a memory for holding data, and a control circuit for controlling the modulation circuit and the memory, the control circuit receiving an output of the demodulation circuit. The non-contact data carrier further comprises switching means for supplying power of an internal battery to a main circuit unit when the carrier signal is detected, electric-supply means for rectifying the carrier signal and generating a voltage, and electric-supply switching means to which an output of the electric-supply means and an output of the switching means are input. The electric-supply switching means compares a voltage value of the battery and a voltage value of the electric-supply means, and switches between the battery and the electric-supply means.
According to the above-described configuration, when the battery is capable of supplying power, power is supplied from the battery, so that long-distance communication is realizable. In case of battery exhaustion, power is supplied by induced electromotive force from the question unit by using the non-contact data carrier in the proximity of the question unit, so that the function of the non-contact data carrier can be maintained.
Moreover, in the non-contact data carrier according to another aspect of the present invention, the level of the carrier signal and a predetermined reference level are compared with each other by the carrier signal detection means. When the level of the carrier signal is higher than the reference level, the switching means goes into on state. When the switching means is in on state, the voltage value of the battery and the value of the voltage generated by the electric-supply means are compared. When the voltage value of the battery is higher than the value of the generated voltage, power of the battery is output to the main circuit unit by the electric-supply switching means.
Moreover, the voltage of the electric-supply means obtained by the received signal and the battery voltage are compared with each other. When the voltage obtained by the received signal is higher than the battery voltage, the power supply from the battery is stopped. When the voltage obtained by the received signal is lower, power is supplied from the battery. Thereby, the power consumption of the battery of the non-contact data carrier is reduced, the battery life is increased.
A non-contact data carrier system of the present invention comprises a non-contact data carrier held by a user of a car, and a question unit mounted in the car. The question unit performs information transmission and reception with the data carrier. The non-contact data carrier stores information such as an ID number therein and performs processing according to information transmitted from the question unit. The question unit comprises switching means for switching operation condition and lock control means for controlling door lock means based on a control signal from the question unit. Since the control of door lock means is performed based on the information such as an ID number stored in the non-contact data carrier, security is maintained.
In the question unit of the non-contact data carrier system of the present invention, an antenna is pasted on a front door of a car, preferably, on a driver side window pane, or an antenna is printed on a window pane. Communication with the non-contact data carrier is performed through the antenna. The switching means for switching operation condition of the question unit is disposed in the proximity of the antenna and comprises a touch switch circuit and a lock control unit. A sensor of a touch switch is provided on the door lever of the driver""s seat side, and communication between the non-contact data carrier and the question unit can be performed only when the touch switch is on. Door locking and unlocking can be performed only by the door lever being touched by the user holding the non-contact data carrier. As a result, the user""s convenience greatly improves.
Further, by providing the timer circuit in the switching means, even when on state of the touch switch is continued for a long time by mischief and the like, the question unit can be brought into wait state after a predetermined time period has elapsed according to counting by the timer circuit. Thereby, not only power consumption due to continuous transmission of signal from the question unit can be reduced but also frequent switching of door lock condition, that is, frequent repetition of locking and unlocking can be prevented.
In the non-contact data carrier system according to another aspect of the present invention, when the user brings the switching means into on state, the question unit transmits a signal to the non-contact data carrier. The question unit determines the contents of the signal returned from the non-contact data carrier and performs the control of the door lock by the control means. The signal returned from the non-contact data carrier is produced based on information transmitted from the question unit and the ID information stored in the non-contact data carrier. The returned signal includes information on the question unit, therefore it is difficult to obtain the data necessary for door lock control even if attempt is made to analyze the internal structure of the non-contact data carrier. Thus, the non-contact data carrier system provides high confidentiality.

Matsushita Electric Industrial Co., Ltd.


A portable UV detection apparatus is disclosed. In one embodiment, the UV detection apparatus includes a UV detection device integrated with a skin type measuring device. A controller can be included in the apparatus that is in communication with the skin type measuring device and the UV detection device. The controller can provide information to the user regarding the amount of ultraviolet radiation present in the environment. In an alternative embodiment, the UV detection apparatus includes a UV detection device in conjunction with a light sensor. The light sensor can be configured to activate the UV detection device should light at a particular intensity be present in the environment. The UV detection device as described above can be configured to measure UVA radiation, UVB radiation, and/or UVC radiation.

Ultraviolet (UV) light has shorter wavelengths than visible light. Ultraviolet light is emitted by the sun. In particular, the sun emits ultraviolet A ("UVA") radiation, ultraviolet B ("UVB") radiation, and ultraviolet C ("UVC") radiation. UVA radiation has longer wavelengths than UVB radiation or UVC radiation. UVA radiation, for instance, has wavelengths from 400 nm to 320 nm. UVB radiation, on the other hand, has wavelengths from 320 nm to 280 nm, while UVC radiation has wavelengths less than 280 nm.
Most of the ultraviolet radiation that passes through the Earth's atmosphere is UVA radiation. UVB radiation and UVC radiation, although smaller in presence, can be the most damaging to one's skin. For example, UVB radiation and UVC radiation have shorter wavelengths and therefore are the highest energy ultraviolet light. All forms of ultraviolet radiation, however, can be damaging to one's skin if left overexposed.
In the past, in order to protect oneself from the harmful effects of ultraviolet radiation, consumers have applied various sunscreens. Sunscreens, for instance, can be made with different Sun Protection Factor (SPF) values. The SPF values relate to the amount of protection that the sunscreen composition affords. SPF numbers, for instance, can range from as low as 2 to as high as 60. These numbers refer to the ability of the sunscreen product to screen or block out ultraviolet light, particularly UVA light. The SPF rating is calculated by comparing the amount of time needed to produce a sunburn on protected skin to the amount of time needed to cause a sunburn on unprotected skin. For example, ideally a person who applies sunscreen with an SPF value of 2 should be able to stay in the sun for twice as long without developing a sunburn. Similarly, if a person were to apply a sunscreen with an SPF value of 15, he/she should be able to remain exposed in the sun for 15 times longer before a sunburn develops.
Unfortunately, SPF values as applied to sunscreens are not always accurate. SPF values, for instance, do not always take into account the amount of B type or C type ultraviolet light present in the environment.
In view of the above, various manufacturers have recently developed ultraviolet sensors that are intended to help consumers monitor ultraviolet rays being admitted from the sun. Such UV sensors can, for instance, measure the amount of ultraviolet light present and provide a recommended exposure time based upon a person's skin type and/or the type of sunscreen that the person is using. For instance, the Chaney Instruments Company markets and sells a product called the UV Skin Care Sensor. The Vernier Software and Technology Company also markets and sells UVA sensors and UVB sensors.
The present disclosure is directed to further improvements in UV detection devices and is directed to further methods and products that are intended to assist consumers in preventing overexposure to UV radiation.


The present invention relates to an all gas-phase process for the purification of single-wall carbon nanotubes and the purified single-wall carbon nanotube material. Known methods of single-wall carbon nanotube production result in a single-wall carbon nanotube product that contains single-wall carbon nanotubes in addition to impurities including residual metal catalyst particles and amounts of small amorphous carbon sheets that surround the catalyst particles and appear on the sides of the single-wall carbon nanotubes and “ropes” of single-wall carbon nanotubes. The purification process removes the extraneous carbon as well as metal-containing residual catalyst particles. The process comprises oxidation of the single-wall carbon nanotube material, reduction and reaction of a halogen-containing gas with the metal-containing species. The oxidation step may be done dry or in the presence of water vapor. The present invention provides a scalable means for producing high-purity single-wall carbon nanotube material.

Fullerenes are spheroidal, closed-cage molecules consisting essentially of sp2-hybridized carbons typically arranged in hexagons and pentagons. Fullerenes, such as C60, also known as Buckminsterfullerene, more commonly, "buckyballs," and C70, have been produced from vaporized carbon at high temperature. Presence of a transition metal catalyst with the high temperature vaporized carbon results in the formation of single-wall tubular structures which may be sealed at one or both ends with a semifullerene dome. These carbon cylindrical structures, known as single-wall carbon nanotubes or, commonly, "buckytubes" have extraordinary properties, including both electrical and thermal conductivity and high strength.
Nested single-wall carbon cylinders, known as multi-wall carbon nanotubes, possess properties similar to the single-wall carbon nanotubes; however, single-wall carbon nanotubes have fewer defects, rendering them stronger, more conductive, and typically more useful than multi-wall carbon nanotubes of similar diameter. Single-wall carbon nanotubes are believed to be much more free of defects than are multi-wall carbon nanotubes because multi-wall carbon nanotubes can survive occasional defects by forming bridges between the unsaturated carbon of the neighboring cylinders, whereas single-wall carbon nanotubes have no neighboring walls for defect compensation.
In defining the size and conformation of single-wall carbon nanotubes, the system of nomenclature described by Dresselhaus et al., Science of Fullerenes and Carbon Nanotubes, 1996, San Diego: Academic Press, Ch. 19, will be used. Single-wall tubular fullerenes are distinguished from each other by a double index (n, m), where n and m are integers that describe how to cut a single strip of hexagonal graphite such that its edges join seamlessly when the strip is wrapped onto the surface of a cylinder. When n=m, the resultant tube is said to be of the "arm-chair" or (n, n) type, since when the tube is cut perpendicularly to the tube axis, only the sides of the hexagons are exposed and their pattern around the periphery of the tube edge resembles the arm and seat of an arm chair repeated n times. When m=0, the resultant tube is said to be of the "zig zag" or (n, 0) type, since when the tube is cut perpendicular to the tube axis, the edge is a zig zag pattern. Where n≠m and m≠0, the resulting tube has chirality. The electronic properties are dependent on the conformation, for example, arm-chair tubes are metallic and have extremely high electrical conductivity. Other tube types are metallic, semi-metals or semi-conductors, depending on their conformation. Regardless of tube type, all single-wall nanotubes have extremely high thermal conductivity and tensile strength.
Several methods of synthesizing fullerenes have developed from the condensation of vaporized carbon at high temperature. Fullerenes, such as C60 and C70, may be prepared by carbon arc methods using vaporized carbon at high temperature. Carbon nanotubes have also been produced as one of the deposits on the cathode in carbon arc processes.
Single-wall carbon nanotubes have been made in a DC arc discharge apparatus by simultaneously evaporating carbon and a small percentage of Group VIIIb transition metal from the anode of the arc discharge apparatus. These techniques allow production of only a low yield of carbon nanotubes, and the population of carbon nanotubes exhibits significant variations in structure and size.
Another method of producing single-wall carbon nanotubes involves laser vaporization of a graphite substrate doped with transition metal atoms (such as nickel, cobalt, or a mixture thereof) to produce single-wall carbon nanotubes. The single-wall carbon nanotubes produced by this method tend to be formed in clusters, termed "ropes," of about 10 to about 1000 single-wall carbon nanotubes in parallel alignment, held by van der Waals forces in a closely packed triangular lattice. Nanotubes produced by this method vary in structure, although one structure tends to predominate. Although the laser vaporization process produces an improved yield of single-wall carbon nanotubes, the product is still heterogeneous, and the nanotubes tend to be too tangled for many potential uses of these materials. In addition, the laser vaporization of carbon is a high energy process.
Another way to synthesize carbon nanotubes is by catalytic decomposition of a carbon-containing gas by nanometer-scale metal particles supported on a substrate. The carbon feedstock molecules decompose on the particle surface, and the resulting carbon atoms then precipitate as part of a nanotube from one side of the particle. This procedure typically produces imperfect multi-walled carbon nanotubes.
Another method for production of single-wall carbon nanotubes involves the disproportionation of CO to form single-wall carbon nanotubes and CO2 on alumina-supported transition metal particles comprising Mo, Fe, Ni, Co, or mixtures thereof. This method uses inexpensive feedstocks in a moderate temperature process. However, the yield is limited due to rapid surrounding of the catalyst particles by a dense tangle of single-wall carbon nanotubes, which acts as a barrier to diffusion of the feedstock gas to the catalyst surface, limiting further nanotube growth.
Control of ferrocene/benzene partial pressures and addition of thiophene as a catalyst promoter in an all-gas-phase process can produce single-wall carbon nanotubes. However, this method suffers from simultaneous production of multi-wall carbon nanotubes, amorphous carbon, and other products of hydrocarbon pyrolysis under the high temperature conditions necessary to produce high quality single-wall carbon nanotubes.
More recently, a method for producing single-wall carbon nanotubes has been reported that uses high pressure CO as the carbon feedstock and a gaseous transition metal catalyst precursor as the catalyst. ("Gas Phase Nucleation and Growth of Single-Wall Carbon Nanotubes from High Pressure Carbon Monoxide," International Pat. Publ. WO 00/26138, published May 11, 2000 ("WO 00/26138"), incorporated by reference herein in its entirety). This method possesses many advantages over other earlier methods. For example, the method can be done continuously, and it has the potential for scale-up to produce commercial quantities of single-wall carbon nanotubes. Another significant advantage of this method is its effectiveness in making single-wall carbon nanotubes without simultaneously making multi-wall nanotubes. Furthermore, the method produces single-wall carbon nanotubes in relatively high purity, such that less than about 10 wt % of the carbon in the solid product is attributable to other carbon-containing species, which includes both graphitic and amorphous carbon.
All known processes for formation of single-wall nanotubes involve a transition-metal catalyst, residues of which are invariably present in the as-produced material. Likewise, these processes also entail production of varying amounts of carbon material that is not in the form of single-wall nanotubes. In the following, this non-nanotube carbon material is referred to as "amorphous carbon."
There are chemical processes involving single-wall carbon nanotube manipulation for specific applications, such as, for example, "Chemical Derivatization Of Single-Wall Carbon Nanotubes To Facilitate Solvation Thereof; And Use Of Derivatized Nanotubes," International Pat. Publ. WO 00/17101, published Mar. 30, 2000, and "Carbon Fibers Formed From Single-Wall Carbon Nanotubes," International Pat. Publ. WO 98/39250, published Sep. 11, 1998, both of which are incorporated by reference herein. Many of these manipulation processes involve chemical reaction of the single-wall carbon nanotube sides and/or ends with other chemicals. These processes also often involve the physical interaction (through van der Waals or other inter-molecular forces) of nanotubes with one another or interaction of nanotubes with other matter within which they are suspended, encapsulated, or otherwise placed in proximity. Clearly, in performing a chemical or physical interaction process with nanotube material, any impurities present are likely to inhibit or modify such manipulation process and/or physical interactions making it difficult or even impossible to achieve the intended result.
One example of a nanotube interaction that has many uses is the process of self-assembly of nanotubes. Under some conditions, individual nanotubes self-assemble into "ropes" of many parallel nanotubes in van der Waals contact with one another. See, e.g., "Macroscopic Ordered Assembly of Carbon Nanotubes," International Pat. Publ. WO 01/30694 A1, published May 3, 2001, incorporated herein by reference. Likewise, individual single-wall carbon nanotube and ropes of single-wall carbon nanotube, can be caused to aggregate into large networks, which are themselves electrically conductive. This self-assembly process enables nanotubes and ropes of nanotubes to form such networks when they are suspended in a matrix of a different material. The presence of this network alters the electrical properties of a composite that includes nanotubes. The facility with which single-wall carbon nanotubes aggregate into ropes and networks is critically dependent upon the purity of the nanotube material.
Another example of nanotube manipulation is the chemical processing of nanotubes by reacting them with other chemicals to produce new materials and devices. Clearly, the presence of other species such as the transition metal catalyst or amorphous carbon material provides sites for chemical reaction processes that are distinct from the desired chemical reaction process involving the nanotube alone. As with any species involved in a chemical process, one seeks to perform that process with a pure species.
Likewise, the useful properties and behavior of nanotube-containing materials devices and articles of manufacture derive from the properties of the nanotubes themselves, and the absence of impurities in the nanotube material enhances the performance of any and all materials, devices, and articles of manufacture comprising nanotubes. Particular examples are those where the material, device, or article of manufacture must function in a high magnetic field or a chemically-active environment. Examples of such materials, device and articles would include those subjected to traditional nuclear magnetic resonance apparatus; those serving as electrodes in batteries, capacitors, sensors, and fuel cells; those implanted in or otherwise in contact with any living organism; those used in preparation of other materials requiring low-contamination environments (such as chemical apparatus, chemical storage devices, electronic materials and devices, or food processing equipment).
In environments where there are chemicals, such as oxygen, that react with the nanotubes at elevated temperatures, the presence of metallic particles reduces the temperature at which the nanotube material remains stable. This occurs because transition metals and transition metal compounds are known to catalyze the reaction of the nanotubes with other chemicals, such as oxygen, at elevated temperatures. High purity nanotubes, with the transition metal species substantially removed, would provide greater chemical stability to the nanotubes and a longer performance life to applications involving them.

This patent is subject to a terminal disclaimer.

Gas-phase process for purifying single-wall carbon nanotubes and compositions thereof


A method for producing ethanol from lignocellulosic biomass using yeast at low cost is provided. The method of the present invention for producing ethanol from lignocellulosic biomass includes steps of (1) pretreating lignocellulosic biomass, (2) treating a cellulose fraction obtained in Step (1) with a cellulose hydrolase, (3) mixing saccharified biomass obtained in Step (2) with yeasts to perform ethanol fermentation, and (4) subjecting a fermentation product obtained in Step (3) to a solid-liquid separation, wherein a cycle consisting of Steps (1), (2), (3) and (4) is repeated twice or more, and yeasts obtained in Step (4) are used as all or a portion of yeasts in Step (3) of the subsequent cycle.

Recently, since there is a concern that fossil fuels are feared to be exhausted, alternative fuels are being developed. In particular, bioethanol derived from biomass has attracted attention. This is because biomass is a renewable resource, which exists in large amounts on the earth, and can be used without increasing carbon dioxide in the air (carbon neutral) so as to contribute to the prevention of global warming.
However, bioethanol is produced mainly from corns or sugarcanes nowadays, and therefore, there is a problem in that bioethanol competes with food. Therefore, in the future, the production of bioethanol from lignocellulosic biomass such as rice straw, wheat straw, waste wood or the like that does not compete with food will be required.
The lignocellulosic biomass includes mainly three components that are cellulose, hemicellulose and lignin. Cellulose is decomposed (saccharified) into glucoses by hydrolysis, and thus, can be used in ethanol fermentation by a yeast Saccharomyces cerevisiae that can utilize glucose.
Cellulose hydrolases such as cellulase are generally used to hydrolyze cellulose, and a pretreatment for separating cellulose from biomass and exposing it is performed prior to the enzymatic reaction in order to facilitate the enzyme reacting with cellulose. Conventionally, a hydrothermal decomposition method, an acid treatment method and an alkaline treatment method have been known as the pretreatment. A method of using dilute acid in a high temperature (200° C. or higher) and a method of using concentrated sulfuric acid or the like are known as the acid treatment method. However, since cellulose is partially decomposed under severe conditions by the hydrothermal decomposition method or by the acid treatment method, there is a problem in that over-decomposed products (by-products) are produced, glucose yield (saccharification rate) is low, and substances that inhibit the ethanol fermentation can be also produced.
Lignocellulosic biomass pretreatment products are subjected to an enzymatic treatment. In the enzymatic treatment, a cellulose component and a hemicellulose component included in the pretreatment products are hydrolyzed to produce oligosaccharides and monosaccharides. However, since the potency of the commercially-available enzyme used in the saccharification is low and thus a large amount of the enzyme is needed for sufficient saccharification, there is a problem in that the cost is increased.
On the other hand, attempts have been made in which the yeast Saccharomyces cerevisiae or the like that cannot originally utilize cellulose, hemicellulose and the like is modified using a bioengineering technique to produce ethanol directly from the biomass pretreatment products. A cell surface display technique is used as such a bioengineering technique. For example, a yeast displaying the group of enzymes that hydrolyze cellulose, that is, endoglucanase, cellobiohydrolase, β-glucosidase and the like, on its surface is produced using the cell surface displaying technique (Patent Document 1).


A rotational angle detection apparatus is provided with a magnet disposed so as to be rotatable integrally with an axis of rotation, having a substantially circular shape when viewed along the axis of rotation, and including a magnetization vector component in a direction orthogonal to the axis of rotation; a magnetic sensor that outputs a sensor signal on the basis of change in a magnetic field accompanying rotation of the magnet; and a rotational angle detector that detects a rotational angle of the rotating body on the basis of the sensor signal output by the magnetic sensor; wherein the magnet has a curved inclined surface with a concave shape along the axis of rotation from a prescribed position on the outer side in a radial direction toward the axis of rotation, and when a circular virtual plane orthogonal to the axis of rotation and centered at the axis of rotation is established at a position opposed to the curved inclined surface, the magnetic sensor is disposed at a position at which the amplitudes of a magnetic field intensity Hr in a radial direction and a magnetic field intensity Hθ in a circumferential direction on the virtual plane are substantially the same, and the magnetic field intensities Hr and Hθ in the radial direction and/or the circumferential direction is output as the sensor signal.

Conventionally, a rotational angle detection apparatus for detecting the rotational angle of a rotating body has been used in a variety of applications. As this kind of rotational angle detection apparatus, an apparatus has been known that is provided with a magnet fixed so as to rotate integrally with the rotating body, and a magnetic sensor element for detecting changes in the intensity of a magnetic field accompanying rotation of the magnet. In such a rotational angle detection apparatus, the magnetic sensor element outputs a signal indicating the relative positional relationship between the rotating body and the magnetic sensor element.
As a conventional rotational angle detection apparatus, as shown in FIG. 37A and FIG. 37B, an apparatus has been known in which a magnet 200 formed in a disk shape is supported by and fixed to a shaft S (axis of rotation) such that a first surface 201 and a second surface 202 of the magnet 200 are orthogonal to the shaft S (axis of rotation), and magnetic sensor elements (Hall elements) 300 are positioned directly below the outer perimeter of the second surface 202 of the magnet 200 and in a circumferential direction centered on the shaft S (axis of rotation),(see Patent Literature 1).
In the above-described rotational angle detection apparatus, there are cases in which the magnet 200 supported by and fixed to the shaft S (axis of rotation) moves slightly in a radial direction, due to axial shaking occurring in which the shaft S (axis of rotation) moves slightly in a radial direction. On the other hand, the magnetic sensor element (Hall element) 300 is positioned to measure the magnetic flux density in a direction parallel to the shaft S (axis of rotation), at the corner of the outer perimeter of the magnet 200. Consequently, the problem exists that accompanying slight movements of the magnet 200, the measured value of the magnetic flux density measured by the magnetic sensor element (Hall element) 300 fluctuates greatly, and the measurement error in the angle of rotation becomes large.
Hence, conventionally, as shown in FIG. 38A and FIG. 38B, a rotational angle detection apparatus has been proposed in which a magnet 210 is supported by and fixed to the shaft S (axis of rotation) and includes a first surface 211 and a second surface 212 which is opposed to the first surface 211 and a magnetic sensor element (Hall element) 310 is positioned directly below the outer perimeter edge of the magnet 210. The magnet 210 includes a chamfer 213 (inclined surface) formed by removing a corner of the outer perimeter edge of the first surface 211 side over the entire perimeter. The magnet 210 is arranged such that a portion of the detection surface of the magnetic sensor element (Hall element) 310 is positioned directly below the chamfer 213 (inclined surface), and the remaining portion is positioned to the outside of the outer perimeter edge of the magnet 210 (see Patent Literature 2).

Rotational angle detection apparatus and rotating machine apparatus