A miniature microwave antenna is disclosed which may be utilized for biomedical applications such as, for example, radiation induced hyperthermia through catheter systems. One feature of the antenna is that it possesses azimuthal directionality despite its small size. This directionality permits targeting of certain tissues while limiting thermal exposure of adjacent tissue. One embodiment has an outer diameter of about 0.095″ (2.4 mm) but the design permits for smaller diameters.

1. Field of the Invention
The present invention relates generally to microwave antennas and, more specifically, to a miniaturized directional microwave antenna for microwave therapy purposes that is highly suitable for use in catheters or syringes where limited space is available.
2. Description of Prior Art
Microwaves are utilized in various medical treatments. As one possible example, microwave ablation therapy may be utilized to treat damaged heart tissues or other tissues containing malignant or harmful cells. During microwave ablation treatments, the damaged tissue to be ablated may be located in one azimuthal direction with respect to the antenna whereas healthy tissue may be positioned in another azimuthal direction with respect to the antenna. It may often be desirable to ablate the damaged tissue by producing therein an increase in temperature while simultaneously limiting the increase in temperature in the healthy tissue.
Antenna directionality implies a focusing of energy. Higher antenna directionality or focusing generally requires a larger size antenna due to the need to provide antenna focusing elements or means. Non-limiting examples of focusing elements may comprise parasitic and/or active antenna elements, reflectors, directors, and the like. Within the small confines of a small diameter catheter or a syringe, there is seldom sufficient room for an aperture large enough to provide antenna directionality.
Several variations of monopole antennas have been used in the prior art for supplying RF or microwave frequency electromagnetic radiation in medical applications, often through the use of a catheter. These antennas typically have the property that radiation around the antenna (azimuthal radiation) is fairly symmetric. This can be disadvantageous in many instances, as discussed above, in which directionality is preferred in order to protect tissue on one side of the antenna while supplying energy to the opposite side.
In some prior art applications, a catheter-based antenna has been routed to an organ wherein sufficient interior space is available that permits expansion of the antenna. The antenna expands in order to increase the aperture size of the antenna, and hence, the directivity, e.g., Gu, Z., Rappaport, M., Wang, P. J., and VanderBrink, B. A., "Development and experimental verification of the wide-aperture catheter-based microwave cardiac ablation antenna", IEEE Trans. On Microwave Theory and Techniques, vol. 48, November 2000). Accordingly, these antennas are limited to use in special regions of the body.
The following patents disclose prior art efforts related to the above-described and/or other problems and studies:
U.S. Pat. No. 4,204,549, issued May 27, 1980, to Paglione discloses an apparatus for hyperthermia treatment that provides transmission of microwave energy for irradiation of tissues and simultaneous and concurrent and continuous measurement of the temperature of the heated tissues at the site of the treatment. The microwave energy is supplied to the site of treated tissue by a coaxial applicator, which is positioned near the tissue.
U.S. Pat. No. 4,311,154, issued Jan. 19, 1982, to Sterzer et al discloses an apparatus that uses microwave energy for the therapeutic and hyperthermic treatment of an internal body organ such as the prostate gland. An irregularly shaped coaxial applicator having a narrow portion and a wide portion is inserted through the male anus into the rectum such that a substantially maximum intensity of the microwave energy irradiates the prostrate gland for preferential heating of the prostate gland and a substantially minimum intensity irradiates untreated tissue. Temperature sensing means are positioned on the periphery of the applicator to measure the tissue environment irradiated by the microwave energy. A controller, operating with the temperature sensing means, is provided to maintain the temperature of the tissue environment within a desired temperature range.
U.S. Pat. No. 4,601,296, issued Jul. 22, 1986, to Yerushalmi, discloses an apparatus for hyperthermic treatment of tumors comprising a probe insertable into a body cavity in the vicinity of a tumor to be treated, the probe including a radiation emitting antenna and a conduit system for the passage of a cooling fluid adjacent the outer surface thereof for cooling of tissue lying adjacent the probe.
U.S. Pat. No. 4,776,086, issued Oct. 11, 1988, to Kasevich et al., discloses a microwave collinear antenna array applicator for in situ or in vivo treatment of tumors and/or other materials by hyperthermia. The array consists of a plurality of harmonically related resonant coaxial antenna elements connected electrically in series to provide uniform heating along the entire length of the array. At the distal end of the array, a resistor may be provided at the inner conductor for steering the heating pattern. At the proximal end of the array, an impedance matching dielectric structure is provided to enable maximum power transfer to the array and to minimize stray leakage currents along the outside of the coaxial transmission line. The array may be made longer or shorter without changing frequency and therefore, depth of penetration by simply adding or subtracting half-wave resonant elements or sections of coaxial transmission line. A lossy sleeve member may be provided around the applicator to provide a localized source of heat.
U.S. Pat. No. 5,026,959, issued Jun. 25, 1991, to Ito et al., discloses an invention that relates to a microwave radiator for warming therapy inserted into a human body to cure focuses of the body such as tumors. It has a first and second high-frequency coaxial cable. The second high-frequency coaxial cable has an inner conductor and a plurality of ring conductors disposed at the outer periphery of the inner conductor via a dielectric. The second high-frequency coaxial cable is inserted into the focuses of the body, and warming therapy can be conducted using radiated electromagnetic waves.
U.S. Pat. No. 5,151,100, issued Sep. 29, 1992, to Abele et al., discloses a catheter device and method for heating tissue. The device has a catheter shaft constructed for insertion into a patient's body, and at least one chamber mounted on the catheter shaft. The catheter shaft has at least one lumen for fluid flow through the shaft. The chambers are defined by walls that are at least in part expandable. Fluid flows, through the lumens, between the chambers and a fluid source outside the body. The chambers can be filled with the fluid after they have been placed within the body. A heating device heats liquid within at least one of the chambers, so that heat is transmitted from the liquid to surrounding tissue by thermal conduction through the wall of the chamber. Means are provided for selectively directing heat transmission toward a selected portion of surrounding tissue. The chambers are fillable with fluid separately from each other, so that the chambers can occupy any of a plurality of possible total volumes. By selecting the total volume of chambers, compression of the tissue can be controlled, and hence the effectiveness of transfer of heat to the tissue can be controlled. According to the method, the catheter device is used to heat tissue from within a duct in a patient's body. The chambers are inserted into the duct and filled with fluid. Liquid is heated within at least one of the chambers, and heat is selectively directed toward a selected portion of surrounding tissue.
U.S. Pat. No. 5,314,466, issued May 24, 1994, to Stern et al., discloses an assembly for steering and orienting a functional element at the distal end of a catheter tube that holds the functional element with its major axis aligned with the axis of the catheter tube for convenient steering to a tissue site. The mechanism can also pivot the functional element in response to an external force to orient the major axis of the functional element generally parallel to the plane of the tissue site, without bending the catheter tube.
U.S. Pat. No. 5,323,778, issued Jun. 28, 1994, to Kandarpa et al., discloses a method for imaging and heating body tissues with one probe, through use of a magnetic resonance imaging radio frequency source. The device may also be configured with a thermocouple to provide temperature-controlled heat therapy with sufficient image definition to control that therapy.
U.S. Pat. No. 5,370,644, issued Dec. 6, 1994, to Langberg, discloses a cardiac ablation apparatus including a solenoidal antenna, monitoring electrodes, and a coupling network at a distal end of a catheter transmission line, and another coupling network at the proximal end of the catheter transmission line to connect the catheter to the source of radiofrequency (RF) power and to an intracardiac electrogram monitor. Solenoidal antenna design includes single and multiple windings with varying geometrical features. Plated plastic tri-axial design of a transmission line offers unitary fabrication. A catheter with variable impedance electrode and gap coatings has features useful for both ablation and for hyperthermia applications.
U.S. Pat. No. 5,694,134, issued Dec. 2, 1997, to Barnes, relates to a phased array antenna for microwave and millimeter wave applications, using either microstrip line, coplanar waveguide, or other construction techniques incorporating a solid dielectric transmission line. A continuously variable phase delay structure which is used to control the beam pattern of the phased array antenna can be applied to the construction of resonant frequency tunable coplanar waveguide antennas and impedance tunable quarter-wave transformers. A thin film of barium strontium titanate or other nonlinear material is deposited upon the coplanar waveguide, and/or the patch antenna element. The dielectric constant of the thin film can be made to vary significantly by applying a DC voltage to the thin film. The propagation constant of a transmission line is directly proportional to the square root of the effective dielectric constant (assuming a lossless dielectric). In an array of multiple antenna elements provided with the feed structure using the disclosed transmission lines, the direction of the resultant main beam of the array can be made to vary over a complete half-sphere with only two adjustable DC voltages applied to the dielectric thin films.
U.S. Pat. No. 5,843,144, issued Dec. 1, 1998, to Rudie et al., discloses a method for treating an individual with diseased prostatic tissue, such as benign prostatic hyperplasia, includes inserting a catheter into a urethra to position a microwave antenna located within the catheter adjacent a prostatic region of the urethra. A microwave antenna is then driven within a power range for applying microwave energy substantially continuously to prostatic tissue to heat the prostatic tissue surrounding the microwave antenna at a temperature and for a time period sufficient to cause necrosis of the prostatic tissue.
U.S. Pat. No. 5,904,709, issued May 18, 1999, and other patents, to Arndt et al., disclose an exemplary method and apparatus for propagating microwave energy into heart tissues to produce a desired temperature profile therein at tissue depths sufficient for thermally ablating arrhythmogenic cardiac tissue to treat ventricular tachycardia and other arrhythmias while preventing excessive heating of surrounding tissues, organs, and blood. A wide bandwidth double-disk antenna is effective for this purpose over a bandwidth of about six gigahertz. A computer simulation provides initial screening capabilities for an antenna such as operating frequency, power level, and power application duration. The simulation also allows optimization of techniques for specific patients or conditions. In operation, microwave energy between about 1 gigahertz and about 12 gigahertz is applied to monopole microwave radiator having a surface wave limiter. A test setup provides physical testing of microwave radiators to determine the temperature profile created in actual heart tissue or ersatz heart tissue. Saline solution pumped over the heart tissue with a peristaltic pump simulates blood flow. Optical temperature sensors disposed at various tissue depths within the heart tissue detect the temperature profile without creating any electromagnetic interference. The method may be used to produce a desired temperature profile in other body tissues reachable by catheter such as tumors and the like.
U.S. Pat. No. 6,245,062, issued Jun. 12, 2001, to Berube et al., discloses a directional reflective shield assembly for a microwave ablation instrument having an antenna coupled to a transmission line. The antenna is formed to generate an electric field sufficiently strong to cause tissue ablation. The shield assembly includes a cradle device disposed about the antenna in a manner substantially shielding a surrounding area of the antenna from the electric field radially generated therefrom. The cradle device further provides a window portion communicating with the antenna which is strategically located relative the antenna to direct a majority of the field generally in a predetermined direction.
U.S. Pat. No. 6,289,249, issued Sep. 11, 2001, and other patents, to Arndt et al., disclose an exemplary method, simulation, and apparatus that are highly suitable for treatment of benign prostatic hyperplasia (BPH). A catheter is disclosed that includes a small diameter disk loaded monopole antenna surrounded by fusion material having a high heat of fusion and a melting point preferably at or near body temperature. Microwaves from the antenna heat prostatic tissue to promote necrosing of the prostatic tissue that relieves the pressure of the prostatic tissue against the urethra as the body reabsorbs the necrosed or dead tissue. The fusion material keeps the urethra cool by means of the heat of fusion of the fusion material. This prevents damage to the urethra while the prostatic tissue is necrosed. A computer simulation is provided that can be used to predict the resulting temperature profile produced in the prostatic tissue. By changing the various control features of the catheter and method of applying microwave energy a temperature profile can be predicted and produced that is similar to the temperature profile desired for the particular patient.
U.S. Pat. No. 6,383,182, issued May 7, 2002, to Berube et al., discloses a directional ablation instrument for ablation of a targeted tissue. The instrument includes a transmission line having a proximal portion suitable for connection to an electromagnetic energy source, and an elongated antenna device having a longitudinal axis and an end coupled to the transmission line. The antenna is adapted to generate an electric field sufficiently strong to cause tissue ablation of the targeted tissue. An elongated support assembly includes a central axis, and an ablation surface extending longitudinally along an exterior surface portion of the support assembly. The support assembly is configured to receive the antenna device in the ablation surface such that the longitudinal axis of the antenna device is off-set from the support assembly central axis. Further, the antenna device is oriented toward the surface portion for positioning of the antenna device substantially adjacent to or in contact with the targeted tissue during operable use.
U.S. Pat. No. 6,527,768, issued Mar. 4, 2003, to Berube discloses a microwave ablation instrument including a transmission line having a first conductor and a second conductor suitable for the transmission of microwave energy. A horn antenna device is mounted to the end of the transmission line, and include an outer conductor and an inner conductor. The outer conductor of the horn antenna is electrically coupled to the second conductor of the transmission line, and includes a peripherally extending interior wall flaring outwardly to define a recess therein. The inner conductor of the horn antenna is electrically coupled to the first conductor of the transmission line and terminates in the outer conductor recess. The inner conductor and the outer conductor cooperate to emit an electromagnetic field sufficiently strong to cause tissue ablation in a direction generally away from the flared interior wall of the outer conductor.
U.S. Pat. No. 6,496,736, issued Dec. 17, 2002, to Carl et al., discloses an exemplary method and apparatus to treat atherosclerosis wherein the artery is partially closed by dilating the artery while preserving the vital and sensitive endothelial layer thereof. Microwave energy having a frequency from 3 GHz to 300 GHz may be propagated into the arterial wall to produce a desired temperature profile therein at tissue depths sufficient for thermally necrosing connective tissue and softening fatty and waxy plaque while limiting heating of surrounding tissues including the endothelial layer and/or other healthy tissue, organs, and blood. The heating period for raising the temperature a potentially desired amount, about 20 degrees Centigrade, within the atherosclerotic lesion may be less than about one second. In one embodiment of the invention, a radically beveled waveguide antenna is used to deliver microwave energy at frequencies from 25 GHz or 30 GHz to about 300 GHz and is focused towards a particular radial sector of the artery. Because the atherosclerotic lesions are often asymmetrically disposed, directable or focused heating preserves healthy sectors or the artery and applies energy to the asymmetrically positioned lesion faster than a non-directed bean. A computer simulation predicts isothermic temperature profiles for the given conditions and may be used in selecting power, pulse duration, beam width, and frequency of operation to maximize energy deposition and control heat rise within the atherosclerotic lesion without harming healthy tissues or the sensitive endothelium cells
U.S. Pat. No. 6,690,963, issued Feb. 10, 2004, to Ben-Haim et al., discloses a locating system for determining the location and orientation of an invasive medical instrument, for example a catheter or endoscope, relative to a reference frame, comprising: a plurality of field generators which generate known, distinguishable fields, preferably continuous AC magnetic fields, in response to drive signals; a plurality of sensors situated in the invasive medical instrument proximate the distal end thereof which generate sensor signals in response to said fields; and a signal processor which has an input for a plurality of signals corresponding to said drive signals and said sensor signals and which produces the three location coordinates and three orientation coordinates of a point on the invasive medical instrument.
U.S. Patent Application Publication No. 2002/0128642, published Sep. 12, 2002, and other publications, to Berube et al., discloses a directional ablation instrument for ablation of a targeted tissue. The instrument includes a transmission line having a proximal portion suitable for connection to an electromagnetic energy source, and an elongated antenna device having a longitudinal axis and an end coupled to the transmission line. The antenna is adapted to generate an electric field sufficiently strong to cause tissue ablation of the targeted tissue. An elongated support assembly includes a central axis, and an ablation surface extending longitudinally along an exterior surface portion of the support assembly. The support assembly is configured to receive the antenna device in the ablation surface such that the longitudinal axis of the antenna device is offset from the support assembly central axis. Further, the antenna device is oriented toward the surface portion for positioning of the antenna device substantially adjacent to or in contact with the targeted tissue during operable use.
Books with related subject matter may include the following:
"Microstrip Lines and Slotlines," 1996, K. C. Bupta et al., published by Artech House, in Norwood Mass., in Chapter 7.
"Design of Nonplanar Microstrip Antennas and Transmission Lines," 1999, by K. L. Wong et al, published by John Wiley & Sons, Inc., New York, N.Y., in Chapter 8.
It would be desirable to provide an antenna that can be made sufficiently small to function as a catheter or syringe antenna and to provide directionality for radiating, with azimuthal directionality, into a biological medium wherein space is not otherwise available. Those skilled in the art have long sought and will appreciate the present invention that addresses these and other problems.

Directional microwave applicator and methods

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


An antenna apparatus for an implantable medical device is adapted and disposed to have an increased telemetry range by providing a plurality of antennas connected in parallel with each other, and physically separated from each other. The antennas may be mounted within the IMD can or they may be located externally, outside the IMD can, but associated and mounted to the IMD can package. The antennas may have coils wound around an air-core or a non-air core such as ferrite. There can be any number of them but it is preferrably a number between 1 and 10.

Since the advent of implantable medical devices, the fields of medicine and electronics have advanced significantly. Accordingly, both the variety and availability of implantable medical devices have increased rapidly. Implantable medical devices to which this invention could be applied currently include not only pacemakers, but also defibrillators, neural stimulators, drug and other therapy delivery systems, monitoring devices some having implanted sensors, and implantable cardioverters, and combinations of these devices, among others.
Early implantable devices were non-invasively controlled to perform simple functions such as turning the device on or off, or adjusting a fixed pacing rate, and even some reporting out of data. These early devices commonly used a magnetic reed switch as a simple telemetry control device. The reed switch could be opened or closed by a magnet held to the patient's skin over the implanted device. In this manner, using the reed switch, the implanted device could be turned on or off. Fixed pacing rates could also be adjusted, for example, by the amount of time the reed switch remained closed, or the number of times it was closed and opened in a given period or a rate or openings and closings, for examples. Such controls, using the reed switch, allowed only for very basic transmittal of signals to implanted devices, and were very limited in function.
As implantable medical devices became more and more sophisticated, the amount of information desired to be transmitted to (and from) the implanted devices grew. Using pacemakers as an example, these functions include switching the device operation into different operating modes, and varying the pacing energy levels delivered to the heart. Pacing rates, device calibration information, and other device parameter settings, and even programming differing therapies and monitoring different body conditions or changing the type of monitoring behavior can also be included in a list of items alterable by and employing the telemetry function. Due to the need to communicate increased amounts of information to implanted medical devices, reed switches became insufficient to adequately perform programming and control functions. As implantable medical devices increased in complexity, it also became desirable for an external programming unit to be able to receive more and better information transmitted by the implanted device. Information that is desirable to be received from an implanted device may include operational status information, information sensed by the implanted medical device such as ECG signals for analysis by a physician, and the like.
There are many telemetry systems that have been used or have been disclosed and these include disclosures on various aspects of such systems particularly suited to implantable devices they are described with reference to in the following U.S. Pat. Nos., which are hereby incorporated by reference:
4,026,305; Brownlee et al., Low Current Telemetry System For Cardiac Pacers PA1 4,267,843; McDonald et al.; Means to Inhibit a Digital Cardiac Pacemaker PA1 4,273,133; Hartlaub et al; Programmable Digital Cardiac Pacemaker with . . . PA1 4,361,153; Slocum et al; Implant Telemetry System PA1 4,373,527; Fischell; Implantable, Programmable Medication Infusion System PA1 4,401.120; Hartlaub et al.; Digital Cardiac pacemaker with Program Acceptance Indicator PA1 4,440,173; Hudziak et al.; Programmable Body Stimulation System PA1 4,515,159; McDonald et al.; Digital Cardiac Pacemaker with Rate Limit Means PA1 4,809,697; Causey, III et al.; Interactive Programming and Diagnostic System for Use With Implantable pacemaker PA1 4,979,506; Silvian; Self-Test System and Method for External Programming Device PA1 5,058,581; Silvian; Telemetry Apparatus and Method for Implantable Tissue Stim . . . PA1 5,107,833; Barsness; Telemetry Gain Adjustment Algorithm and Signal Strength Indication in a Noisy Environment PA1 5,127,404; Wyborny et al., Telemetry Format for Implanted Medical Device PA1 5,137,022; Henery; Synchronous Telemetry System and Method for an Implantable . . . PA1 5,168,871; Grevious; 5,168,871; Method and Apparatus for Processing Quasi Transient Telemetry Signals in Noisy Environments PA1 5,241,961; Henry; Synchronous Telemetry Receiver and Receiving Method for an Implantable Medical Device PA1 5,292,343; Blanchette et al.; Hand Shake For Implanted Medical Device Telemetry PA1 5,324,315 Grevious; Closed Loop Downlink Telemetry and Method for Implantable Medical Device PA1 5,344,431; Merritt et al., Method and Apparatus for Determination of End-Of-Service For Implantable Devices PA1 5,354,319; Wyborny, et al., Telemetry System for an Implantable Medical Device PA1 5,350,411; Ryan et al.; Pacemaker Telemetry System PA1 5,562,714; Grevious; Magnetic Field Strength Regulator for Implant PA1 5,569,307 Schulman et al.; Implantable Cochlear Stimulator having Backtelemetry Handshake Signal PA1 5,693,076; Kaemerer; Compressed Patient Narrative Storage and Full Text Reconstruction From Implantable Medical Devices PA1 A is the coil area in square meters, PA1 F=signal frequency in Hertz, .lambda.=freespace wavelength in meters PA1 Q.sub.s is the coil's in-circuit loaded quality factor PA1 R.sub.S is the total in-circuit loss seen by the coil PA1 I.sub.in is the coil current in amperes, and PA1 R is the link range in meters.
The above-mentioned patents are all incorporated hereinto by this reference. They describe telemetry problems and solutions that run the gamut from dealing with reed switch/device interaction, to protocol for communicating via telemetry, to assisting in the programming of the device, to making adjustments for signal strength. While the list is not exhaustive it is believed to roughly represent the state of the art. Of most relevance to this invention are the ones concerned with adaptation to signal strength, but the others do provide useful background. For this invention we are most concerned with antenna configuration and use, and the prior art in this area is not well developed for the implantable device field.
Typical telemetry systems for implantable medical devices operate with a radio-frequency (RF) transmitter and receiver in both the device and in the external programming unit. The device transmitter and receiver typically use a wire coil element for receiving telemetry signals. The telemetry signals are received from a hand held programming head which is connected to the programming unit, and which is positioned over the implant site in close proximity to the implant. The device transmitter communicates signals to the external programming unit through the programming head. Signals transmitted to the implantable medical device in this fashion are referred to as downlink or downlink telemetry. Signals transmitted from the implantable medical device to the external unit are referred to as uplink or uplink telemetry. The usable uplink range of implantable medical devices is usually quite limited due to the small current amplitudes that the uplink transmitters have to work with.
Implanted medical devices typically have an internal battery(although tapping into body provided energy sources is not unheard of), which provides a power source to drive the normal operative functions of the implanted medical device. When a telemetry session is initiated, this battery must also provide power to operate the RF uplink and downlink telemetry circuitry within the device. This battery has an output terminal voltage, which is limited to a small value of typically 2 or 3 volts. Charge pumping a capacitor can alleviate some of this limitation, but the inventor believes that would be a more costly solution and in any event is not discussed here. During the telemetry system, the battery must also supply a DC current from its terminal voltage to continue the normal implanted device circutry operations.
The power delivered from the battery is calculated as the product of the battery's terminal voltage multiplied by the current delivered from the battery. Since the normal operating functions of the internal medical device circuitry cannot be compromised during a telemetry session, the battery power taken to operate the telemetry circuitry must be limited. The telemetry transmitter and the normal operating functional circuitry both operate at the same battery terminal voltage. Consequently, the only way to restrict the battery power consumed for telemetry is to restrict the amount of current used by the telemetry transmitter and its coil antenna.
The amount of battery current taken for telemetry, while minimized, cannot be set to an arbitrary small value because the telemetry system must also operate over a specified minimum uplink range. In general, from the perspective of this invention, the larger the sweet spot that can be provided with the same amount of battery (or other) current, the better.
The range over which a telemetry link provides acceptable signal transfer, especially for the uplink from the implantable device to the programmer is a key factor in the telemetry system design. Other factors being equal, range depends upon the current amplitude delivered to the coil antenna. Any limitation on the amount of current supplied to the IMD telemetry transmitter and coil antenna will directly limit the telemetry uplink range unless the current is used efficiently within the transmitter and coil antenna. The greater the telemetry transmitter and coil antenna current, the greater the telemetry uplink range becomes, at the expense of less current available for the IMD circuitry.
For our purposes, we prefer to do telemetric communication from our implanted device using the near H field from the coil antenna rather than the E field. This is because the H field wave impedance is much less than it is for E field wave impedance, allowing lower loss signal transmission through the metal can which usually forms the shell of the implanted device, and through the flesh and skin. (The near field is generally considered to be less than 1/6th of the wave length of the carrier wave.) Therefore, in our preferred telemetry, uplink telemetry range depends upon the near field magnetic field strength or amplitude for our preferred embodiments. (For devices ata a range close to the body, or having more uplink transmitter power, or with antenna(e) outside of a metal capsule or shell, the E field may be used as well, and then, the electric field strength would be the limiting factor with respect to range. There are other problems with regulatory authorities when using E fields, another reason we prefer the H field as the data transmission vector).
The magnetic field strength depends on the number of coil turns in the antenna, the area of the coil, and the coil current. The uplink transmitter efficiency depends on the coil quality factor, Q. To increase the telemetry uplink range, the magnetic field intensity must be maintained at an increased distance from the implanted device. The magnetic field may be increased by: adding more turns to the coil; making the coil antenna larger in area, winding it with a larger radius; or by driving the coil with a larger coil current. The larger the coil Q, the more efficient the uplink transmitter circuit becomes
It should be noted that, for either uplink or downlink, it would be desirable to utilize only near-field magnetic fields (H fields), which do not require federal licensing since their amplitude falls off so rapidly with link range. Second, it would be desirable to use these near-fields with the within described inventive coil antenna implementation to increase the uplink range of the telemetry by maximizing the transmitted magnetic field strength. This inventive antenna implementatioin provides this range increase by directly dealing with the problem of the limited fixed voltage supplied by the implantable device's battery.
For a fixed coil voltage, adding more turns to the coil will increase the magnetic field intensity generated by the coil. Unfortunately, adding more turns to the coil will increase the coil's self-inductance and its associated input reactance with the result that less current can then be driven into the coil. The resulting coil drive current is then limited because of the fixed (battery) voltage since the coil antenna's inductance and therefore its inductive reactance increase correspondingly with the number of turns in the coil. The magnitude of current flowing in the coil is equal to the battery voltage divided by the inductive reactance of the coil antenna. Therefore, for a fixed coil voltage, adding more turns to the coil actually results in reduced coil current and smaller magnetic field intensity.
Coil antennas with larger areas may be used to increase the magnetic field intensity. The ideal coil antenna design for uplink applications would have an area as large as can be accommodated, either within, or external to the Implantable Medical Device(IMD) can. Unfortunately, the area of the coil antenna is usually not arbitrary. The coil must be small in area to fit within the volume allotted to it by the overall IMD configuration. The coil antenna should have as large an area as possible in order to produce a large uplink sweet spot. Coil antennas with larger areas produce larger sweet spot volumes. The physical configuration of the antenna essentially determines the sweet spot radius and associated volume.
The sweet spot, at a specified range, for uplink telemetry is defined to be a volume above and adjacent to the site of an implanted medical device. Within the sweet spot volume, at the range specified, the telemetry signal voltage received by the external communicating or programming head equals or exceeds a specified value. The received signal voltage is generated by the time varying magnetic flux density within the sweet spot. (The specified value of signal voltage is defined to be an amplitude greater than the lower limit of signal voltage amplitude the expected to be used for reception of the signal). Larger sweet spot volumes are desired in medical telemetry because placement of the programming head within a large volume is simple to acheive and in an operating room or clinical environment. Thus placement of the programming head relative to the implanted device location will not be critical to maintain a strong telemetry uplink signal, because of the relatively large sweet spot volume acheivable with this invention.
The IMD coil antenna should have a Q as large as possible in order to maximize transmitter efficiency. Too large a Q value will also limit the IMD transmitter's 3-dB bandwidth(BW). For a specified transmitter signal bandwidth, the coils' loaded in-circuit Q is defined as, Q=F/BW, (where F is frequency). The loaded, in-circuit coil Q must provide the required signal bandwidth or some of the transmitted uplink telemetry signal power will be lost. So there are limitations to be placed upon the loaded Q value for the IMD coil antenna. Its in-circuit, loaded Q cannot be made arbitrarily large without directly impacting the transmitter signal bandwidth.
The current made available for telemetry is limited by two factors. First, the limited battery voltage available for a telemetry transmitter and coil antenna in an implantable medical device limits the current available to drive the telemetry circuitry. Second, as explained above, the inductive reactance of the coil antenna will limit coil antenna input current. For a fixed voltage driving the coil antenna, at a fixed frequency, as the coil's inductive reactance increases, the coil's input current is reduced. Also, as the life cycle of the IMD battery progresses, the internal resistance of the battery increases. This increased internal resistance further limits the current available from the battery to drive the antenna coil, since the effect of increased internal resistance is to reduce the available terminal voltage from the battery.
A number of potential solutions to the problems of increasing uplink telemetry range, but which do not involve increasing the coil current have been proposed. These methods however have not proven effective.
Larger inductor coil areas would increase the uplink range when driven by small telemetry currents, but usually are not feasible given the small area allotted to the coil in an implantable medical device. The space allocated for the telemetry circuitry and its associated coil antenna is often limited by the volume remaining after the device circuit components (and the battery) have been placed within the implant can.
An increased number of coil turns would provide a larger magnetic field strength to carry the telemetry signals further. However, since the IMD battery voltage is fixed more coil turns will actually limit the coil current because an increased number of coil turns increases the coil's self inductance, and the inductive reactance of the coil antenna, thereby limiting the coil current.
The loaded coil Q factor should also be maintained at the highest possible level to improve transmitter efficiency, but its value must be consistent with maintaining the specified uplink signal bandwidth.
Given the relatively small volume allotted to the coil antenna, fixed battery terminal voltage, self inductance and inductive reactance limitations of the present telemetry antenna technology, it would be desirable to increase the coil transmit current while maintaining the coil quality factor while remaining within size constraints imposed by implantable medical device cases, to increase the uplink telemetry range. The prior art has not provided an acceptable solution for increasing the telemetry range of an implantable medical device.


A handling device, which is in particular a robot, has a receiving device for receiving different instruments. To this end, the receiving device and the different instruments have mutually compatible connecting elements. In order to ensure error-free connection of the correctly selected instrument to the receiving device, the instruments have changeable indicator devices. The indicator devices are changed with the aid of a control device, for example on the basis of a schedule.

1. Field of the Disclosure
The disclosure relates to a handling device and a method for using different instruments with the aid of a receiving device of a handling device.
2. Discussion of the Background Art
Handling devices such as robots, comprise, e.g. on robot arms, receiving devices for receiving instruments, such as e.g. tools. In case of a robot, e.g. of the type used on the medical sector and particularly in surgery, said receiving devices will take up surgical instruments. In such a situation, it can be provided that a given receiving device will take up different instruments. This will involve an exchange of the instruments or tools.
For ensuring that, at a desired point of time, the correct instrument is connected to the receiving device, the instruments can be provided with passive markings such as e.g. inscriptions or the like. With the aid of pre-defined working instructions or a clearly defined working schedule, the required instrument, having been correspondingly marked or identified, will be connected to the receiving device by a user. In medical robots, the connecting of a surgical instrument is performed by a surgical assistant as prescribed by a surgical plan or as instructed by the operating surgeon. This approach is susceptible to faults and is not flexible either.
For avoidance of a wrong connection of instruments to a receiving device, it is further possible to provide unambiguous interfaces. In this case, the interfaces of the components are designed to the effect that only desired connections are possible. The interfaces thus comprise a mechanism which prevents a wrong connection. This approach is inflexible and allows for a mere limited number of connecting options, and, particularly, the approach can be varied only with considerable expenditure.
Further, in machine tools, it is known to provide an automatic changing of tools. For this purpose, the different tools and respectively instruments are kept available in a magazine. In a control unit of the machine tool, a defined working schedule has been preset. On the basis of the working schedule, an automatic changing of tools will be performed. This is achieved in that the machine tool has knowledge of which position of the magazine has which tool arranged in it. Such an automatic changing of tools can be realized only by use of complex devices. In the changing of instruments of a medical robot, such complexity is not practicable.
It is an object of the disclosure to provide a handling device wherein different instruments can be changed in a simple manner while the occurrence of faults is to be avoided. Further, it is an object of the disclosure to provide a method for operating such a handling device.

Handling device and method for operating a handling device

Deutsches Zentrum Fuer Luft-Und Raumfahrt E.V.


A method of making a bullet includes metal injection molding a bullet jacket or preform, and forming the jacket or preform into a bullet.

This section provides background information related to the present disclosure which is not necessarily prior art.
This invention relates to bullets and methods of making bullets.
Jacketed bullets are conventionally made by forming a cup-shaped jacket preform, inserting a core, and forming the jacket preform and core into a bullet. While this process is efficient and relatively inexpensive, it put certain limits or restrictions on the design of the bullet.
Embodiments of the present invention provide bullets and new methods of making bullets. Generally, a first preferred embodiment of a method of making a bullet according to the principles of this invention comprises metal injection molding a bullet jacket of a first material. The jacket comprises back, and a sidewall projecting forwardly and outwardly from the back. The sidewall has a rearward portion and a forward portion, with the wall thickness of the rearward portion increasing toward the forward portion, and the wall thickness of the forward portion decreasing toward the forward end. A core of a second material is inserted into the rearward portion of the sidewall. The jacket is formed around the core to form a bullet with a generally cylindrical rearward portion and a forward portion that tapers toward the forward end, with an open forward end. The juncture between the rearward portion of the jacket and the forward portion of the jacket impinges on and retains the core.
Preferably, a plurality of lines of weakness are formed in the forward portion of the jacket during the metal injection molding process. A tip can be disposed in the open forward end of the jacket.
Generally, a second preferred embodiment of a method of making a bullet according to the principles of this invention comprises metal injection molding a bullet preform having a generally cylindrical shape with solid rearward portion, and a hollow forward portion open to the front of the bullet preform. The forward portion of the bullet perform is formed into a tapering configuration with an open front end. The hollow forward portion has a generally cylindrical rearward portion of a first diameter; a generally frustoconical intermediate portion; and a generally cylindrical forward portion of a second diameter, larger that the first diameter. The walls of the generally frustoconical intermediate portion of the cavity have a generally S-shaped configuration. A tip can be disposed in the open forward end of the jacket.
Generally, a third preferred embodiment of a method of making a bullet according to the principles of this invention comprises metal injection molding a bullet preform, the bullet preform having a generally cylindrical shape with solid rearward portion, and a hollow forward portion open to the front of the bullet preform. The hollow is formed by a cavity in the forward portion extending at least 50% of the total length of the preform The forward portion of the bullet perform is formed into a tapering configuration with an open front end. The hollow has a generally widening rearward portion; a generally frustoconical intermediate portion; and a generally widening forward portion of a second diameter, each of the three portions widening toward the front of the preform. The slopes of the rearward and forward portions are less than the slope of the intermediate portion. The walls of the generally frustoconical intermediate portion can have a generally S-shaped configuration. A tip can be disposed in the open forward end of the jacket.
Generally, a fourth preferred embodiment of a method of making a bullet according to the principles of this invention comprises metal injection molding a partition bullet jacket of a first material. The jacket has a partition having a forwardly projecting sidewall forming a forward cup, and a rearwardly projecting sidewall forming a rearward cup. A rear core is inserted tin in the rear cup and at least a portion of the rear cup is deformed to engage the rear core in the rear cup. A forward core is inserted into the forward cup and at least a portion of the forward cup is deformed to form a tapering forward portion of the bullet and engage the forward core therein. The forward cup is formed into the tapering forward portion of the bullet with an open forward end, and a pointed tip is disposed in the open forward end of the jacket. The thickness of the sidewall of the forward cup of the jacket is greater adjacent the partition than adjacent the forward edge of the cup.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.


The class D amplifier comprises a voltage control current source circuit for current-converting the voice voltage signal Vsin of the input into two signals with different polarities, two capacitance elements for integration where the electric charges of the each current-converted signal and the feedback signal are stored respectively, two hysteresis comparators for PWM conversion for comparing the potentials of the two capacitance elements for integration and a reference potential Vcom respectively, two output buffers for amplifying the outputs thereof respectively, and two constant current source feedback circuits for feeding back the output thereof respectively.

1. Field of the Invention
The present invention relates to a class D amplifier to be installed in a portable telephone, for example, and more particularly to a class D amplifier of which the power consumption is decreased.
2. Description of the Related Art
Generally a digital amplifier comprises a comparator receiving an audio signal and a triangular wave carrier wave, putting out a PWM (Pulse Width Modulation) signal, and a class D output stage which amplifies the output of the comparator.
In such a digital amplifier, the comparator compares the audio signal and the triangular wave, and generates the PWM signal. The output stage switch is controlled by this PWM signal, and the load unit, such as a speaker, is driven by the output of the class D output stage. The high frequency component is removed by the output LPF (Low Pass Filter) during driving the load unit.
Practically, however, in a digital amplifier, non-linear distortion is generated due to the curvature of a triangular wave, pulse width distortion and power supply voltage variations, so negative feedback is used to improve non-linear distortion. One of such methods negatively feeds back the output of the output stage to the integrating amplifier installed as an integrating circuit in a previous stage of the comparator. The integrating amplifier extracts and amplifies the low frequency component included in the feedback signal of the square wave (PWM wave).
While this separately-excited oscillation type PWM system operates with such incoming triangular waves, there is a self-excited oscillation type PWM digital amplifier which oscillates by itself without incoming external triangular waves so that the output of the integrating amplifier is a triangular wave (e.g. Japanese Unexamined Patent Application Publication No. 2003-115730). In the self-excited oscillation type PWM system, the triangular wave oscillation circuit is unnecessary, and a Schmitt trigger circuit, for example, is used instead of a comparator.
FIG. 7 is a block diagram depicting a conventional self-excited oscillation type class D amplifier. As FIG. 7 shows, the class D amplifier 101 with a differential output (Bridge-Tied Load: BTL) is comprised of a differential signal output unit 102 consisting of the resistors R101-R104 for converting voice signals from the input terminal Sin into differential signals, and the full differential amplifier A101, and each charge balanced class D amplifier at the P-side and N-side receiving the differential signals.
The N-side charge balanced class D amplifier comprises a PWM waveform generation circuit and a feedback circuit. The PWM waveform generation circuit consists of an integrating amplifier 103N consisting of an operation amplifier A102 and a capacitor C101, and a Schmitt trigger circuit 104N consisting of resistors R107-R109 and a comparator COMP 101. The feedback circuit comprises an output buffer B101 and a resistor R111 for negatively feeding back the output of the output buffer B101 to the integrating amplifier 103N. The PWM waveform generation circuit consisting of the integrating amplifier 103N and the Schmitt trigger circuit 104N, is a self-excited oscillation type oscillation circuit which oscillates automatically without providing triangular waves, and the output of the integrating amplifier 103N is a triangular wave.
The Schmitt trigger circuit 104N, at the power supply level is VDD1, has the following two threshold values according to the output LOW or HIGH for determining LOW and HIGH of the input voltage (output of integrating amplifier 103N).VH=Vcom ((R107+R109)/R109)VL=(Vcom (R107+R109)−VDD1 ×R107)/R109The P-side charge balanced class D amplifier is also configured similar to the N-side, and in the Schmitt trigger circuit 104P, has the following two threshold values according to the output LOW or HIGH for determining LOW and HIGH of the input voltage (output of the integrating amplifier 103P).VH=Vcom ((R108+R110)/R110)VL=(Vcom (R108+R110)−VDD1 ×R108)/R110
Now the operation of a conventional class D amplifier will be described. FIG. 8 is a diagram depicting the signal waveform of each node in the class D amplifier 101, where S11 is a voice signal (analog signal) which comes from the input terminal Sin, S12 is an output waveform of the output buffer B102 when the voice signal is a silent signal, S13 is the P-side output waveform when the voice signal of S11 is presented from Sin, S14 is the N-side output waveform when the voice signal of S11 is provided from the input terminal Sin, and S15 is an amplitude applied to the load to be connected to the subsequent stage of the class D amplifier. FIG. 9 shows the relationship of the output voltage of the integrating amplifier (input voltage of the comparator) and the output voltage (Vout) of the output terminal OUTP where the abscissa is time and the ordinate is voltage.
First the case when voice signals are not provided from the input terminal Sin (voice signal=silent signal) will be described. The non-inverting input terminals of the integrating amplifiers 103N and 103P are connected to the reference potential Vcom respectively, and the non-inverting input terminals of the comparators COMP 101 and 102 are connected to the reference potential Vcom respectively. Each charge balanced class D amplifier at the P-side and the N-side operates similarly, so the operation of only the P-side charge balanced class D amplifier will be described below.
In the case when the voice signal is a silent signal, the voltage Vsin of the non-inverting input terminal of the integrating amplifier 103P is Vsin=Vcom. As FIG. 9A shows, if the output voltage Vout of the output terminal OUTP is HIGH (power supply level) (time T1), the output voltage VA of the integrating amplifier 103P drops since the current flows into the capacitor C102 of the integrating amplifier 103P through the resistor R112. If the output VA of the integrating amplifier 103P goes below the threshold level VL of the comparator COMP 102, the output voltage Vout of the output terminal OUTP goes LOW, and current flows out of the integrating amplifier 103P, so the output voltage VA of the integrating amplifier 103P increases. If the output voltage VA of the integrating amplifier 103P exceeds the threshold level VH of the comparator COMP 102, the comparator COMP 102 puts out HIGH, and the output terminal OUTP goes HIGH. Repeating the operations results in oscillation. At this time, the charge amount that flows into the integrating amplifier 103P from the output terminal OUTP via the feedback circuit and the charge amount which flows out from the integrating amplifier 103P to the OUTP side are equal, so the average output level is equal to the non-inverting input level (Vcom) of the integrating amplifier 103P (S2 in FIG. 8).
Now the case when the voice signal is input from the input terminal Sin will be described. According to the voice signal amplitude from the input terminal Sin shown in FIG. 7, the output level (Aop) of the differential amplifier A101 becomes as follows.Aop=(Vsin−Vcom)×R104/(2×R101)
When the level of Aop is higher than the non-inversing level Vcom of the integrating amplifier A103, current flows into the integrating amplifier A103 from Aop. If the output terminal OUTP is HIGH at this time, the current that flows into the integrating amplifier 103P is the sum of the current from Aop and the current from the feedback circuit, thus as time T1 in FIG. 9B shows, the output voltage reaches the threshold level VL of the comparator COMP 102 and the output terminal OUTP goes LOW sooner compared with the case of a silent signal, that is time T1 in FIG. 9A. This means that the width of HIGH has become shorter. If the output terminal OUTP is LOW, on the other hand, the current that flows into the integrating amplifier 103P is the current from the feedback circuit from which the current from Aop is subtracted, therefore compared with the case of a silent signal, the time to reach the threshold level LH of the comparator COMP2 (time T2) becomes longer. This means that the time period of LOW becomes longer.
This is the same for the case when the level of Aop is at the lower level than Vcom, and as FIG. 9C shows, when the output terminal OUTP is HIGH, time T1 is longer since the current that flows into the integrating amplifier 103P is subtracted, and when the output terminal OUTP is LOW, the time T2 is shorter since the current that flows into the integrating amplifier A103 is added. In this way, PWM waveforms, where the duty of the output pulse changes according to the level of Aop, can be generated as shown in S13 and S14 in FIG. 8.
The output waveform which is acquired by filtering this output is as follows.Vout=(Vsin−Vcom)×R104×R112/(2×R101 ×R106) +Vcom
In other words, the loop from the integrating amplifier 103P at the P-side to the-output buffer B102 has inversing amplifiers connected in a series. This is the same for the loop from the integrating amplifier 103N at the N-side to the output buffer B101.
In this conventional class D amplifier, when the analog signal shown in S11 in FIG. 8 has a level higher than the COM level, the pulse width of HIGH at the P-side output increases, and the pulse width of HIGH at the N-side output decreases. Therefore a plus charge is applied to the load so that output after filtering becomes the waveform according to the input (waveform indicated by the broken line in S15 in FIG. 8). However as S12 in FIG. 8 shows, both the P-side and N-side output the waveforms with a 50% duty at silent signal, and these waveforms are synchronized with the same phases, so although power to be applied to the load becomes 0 in theory, actually unnecessary power is consumed because the output buffer is in clock operation even at silent signal.


A variable speed constant frequency (VSCF) power generator includes a rotating direct current (DC) power source, rotating multi-phase generator main field windings to generate a rotating alternating current (AC) power, and a rotating inverter configured to control alternating current (AC) generator field windings in response to output AC power generated by the VSCF power generator and DC power from the rotating DC power source. At least one generator main field sensor outputs a generator main field feedback signal based on the rotating AC power applied to the rotating multi-phase generator main field windings. Stationary multi-phase generator armature windings output constant voltage constant frequency AC power controlled by the rotating AC power. An electronic rotating power line communication (PLC) controller generates a control signal that adjusts the rotating AC power based on the rotating generator feedback signal, where the output AC power is controlled by adjusting the rotating AC power.

In the simplest terms, power generators convert mechanical energy to electrical energy via the interaction of rotating magnetic fields and coils of wire. A multitude of alternating current (AC) generator systems, for example, have been developed with various means of providing interaction between magnetic fields and coils of wire. For example, an AC generator system may include an auxiliary power unit (APU) generator driven by a gas turbine engine to provide a secondary power source to an aircraft. The AC generator system is typically required to maintain a constant output frequency in order to properly drive electrical systems connected AC generator system output. However, the rotational speed of the drive shaft can vary during operation, thereby varying the respective output frequencies of the APU generator. Variable speed AC generator systems have been developed, which include large exciter assemblies due to the low frequency AC power required to be injected into the main generator field winding. Consequently, the large size of the exciter significantly increases the overall size and weight of conventional variable speed AC generator systems. Moreover, conventional variable speed AC generator systems drive the voltage/frequency controller with rotor mounted power converters via rotating signal transformers. Consequently, conventional variable speed AC generator systems require additional rotating signal transformers to electrically start the engine.

Variable speed constant frequency power generator including permanent magnet exciter


A position adjustment method for adjusting positions of two projection images projected from multiple projectors contained in a multi-projection display onto a projection surface such that the images overlap. A first step involves setting pixel values of colors such that a predetermined characteristic is exhibited in an overlapping area when the adjustment images are projected. A second step involves producing adjustment image data corresponding to the adjustment images. Colors of the adjustment images are allocated to patterns such that the patterns overlap when the adjustment images are projected. A third step involves giving the adjustment image data to the multiple projectors and calculating evaluation values associated with the image data that is obtained by taking an image of the projection surface on which the adjustment images are projected from the multiple projectors. A forth step involves performing position adjustment for the projection images based on the evaluation values.

1. Technical Field
The present invention relates to a position adjustment method for projection images used in a multi-projection display which produces a picture by projecting images from a plurality of projectors onto a projection surface, a position adjustment apparatus for projection images, a position adjustment program for projection images, and a multi-projection display.
2. Related Art
Currently, a multi-projection display which projects images from a plurality of projectors onto a projection surface by tiling projection or stacking projection is known. According to the multi-projection display, the accuracy of position adjustment for the respective projection images on the projection surface has a great effect on the quality of the projection images.
In a case of the tiling projection, for example, low accuracy of position adjustment causes considerable deterioration of the projection image quality such as discontinuous joints between the respective projection images and blurs in the overlapping areas.
To overcome this drawback, position adjustment for the respective projection images is essential, but this requires great time and labor and also high-level position adjustment technique when the position adjustment is manually performed by a user.
Accordingly, various methods for automatically executing position adjustment have been proposed (for example, see JP-A-2001-356005 and JP-A-2002-365718).
According to the technique shown in JP-A-2001-356005, a plurality of test pattern images (which exhibit luminance distributions having mountain-shaped waveforms) projected on a projection surface are taken by a camera to obtain the respective typical positions (central positions of mountain-shaped waveforms) of the plural test patterns from the taken image data. Then, based on the respective typical positions thus obtained, the distances between the respective test pattern images and the distances between the cross points of the line segments connecting the test pattern images and the adjoining pictures in both or either of the horizontal direction and the vertical direction are obtained so as to determine positional displacement based on those distances.
According to the technique disclosed in JP-A-2002-365718, two adjustment patterns each having a black portion along the boundary between adjoining projection images and a white portion located inside the black portion are displayed by two projectors to show a dark line on the overlapping area. Then, the image of the black portion is taken by an image taking device while gradually decreasing the width of the black portion. Subsequently, the width changes of the dark line are observed based on the image data thus taken and the position at which the dark line disappears is stored as a boundary position. Thereafter, position adjustment is conducted such that the contours of the projection images coming from the respective projection devices coincide with the boundary position.
In both the techniques shown in JP-A-2001-356005 and JP-A-2002-365718, adjustment images are projected on the projection surface using two projectors and then are taken by the image taking device so as to perform position adjustment based on the image data thus taken.
According to the technique disclosed in JP-A-2001-356005, displacement can be detected using an image taking device having lower resolution than that of the projection images. However, since complicated image analysis processing is required for displacement detection, an image data processing device having sufficiently high processing performance is needed. Also, since the calculation volume is large, processes required for correcting displacement cannot be carried out at high speed.
According to the technique shown in JP-A-2002-365718, an image taking device having high resolution sufficient for resolving the projection images by pixel is required to obtain the boundary position with high accuracy.
Moreover, when position adjustment is performed using the methods disclosed in JP-A-2001-356005 and JP-A-2002-365718, it is necessary to consider the effect of the illumination condition inside a room where the position adjustment is conducted or in other environment given to the image taking device. This is because appropriate position adjustment cannot be achieved in many cases based on image data each obtained under the environment of different illumination conditions. In an extremely dark environment having no illumination such as a darkroom, for example, the effect of some inhibiting factors which are ignorable under the illumination condition of normal brightness increases and thus prevents achievement of appropriate position adjustment. Examples of the inhibiting factors include the color array structure of color filters used in a single-plate-type image taking device, for example, which will be described later.
Thus, in a case of position adjustment in the extremely dark environment such as a darkroom, consideration for the effect of the inhibiting factors is essential. However, no such consideration is especially discussed for the techniques of JP-A-2001-356005 and JP-A-2002-365718 .

Position adjustment method for projection images


A method for manufacturing a polymer sustained vertical alignment (PSVA) liquid crystal displays (LCD) panel includes: A: layering an alignment film on a substrate; B: forming an active reactive monomer layer on a surface of the alignment film; C: coating a liquid crystal layer on a surface of the active reactive monomer layer; and D: sealing the LC layer, and performing optical alignment on LC molecules of the LC layer.

Today, users have higher demand requirements for display devices. To satisfy such requirements, some flat panel display devices have been rapidly developed in recent years, such as liquid crystal display (LCD) device, Plasma Display Panel (PDP), and Organic Light-Emitting Diode (OLED) display device. In flat panel display devices, LCD devices are gradually replacing cold cathode display devices due to low weight, small volume, and low energy consumption.
An initial LCD mode has a low contrast ratio and a poor viewing angle, such as a twisted nematic (TN) display and a super twisted nematic (STN) display. With the growth of living standards, users demand improved display devices. Thus, some LCD modes having a wide visual angle have developed rapidly in recent years, such as an in-plan switching (IPS) display and a vertical alignment (VA) display.
For the VA display, the LCD device includes a first substrate, a second substrate, and negative liquid crystal (LC) molecules between the first substrate and the second substrate. Transparent conducting layers (indium tin oxide: ITO) are layered on insides of the first substrate and the second substrate, which forms a vertical electric field. The negative LC molecules are embedded between two transparent conducting layers. Dielectric constant of a long axis of the negative LC molecule is less than dielectric constant of a secondary axis of the negative LC molecule, where the secondary axis of the negative LC molecule is perpendicular to the long axis of the negative LC molecule. When the LC molecule is not affected by the vertical electric field, the LC molecule is perpendicular to surfaces of the first and second substrates. When the LC molecule is affected by the vertical electric field, the LC molecule is oriented toward a designated direction and finally arrays along a direction perpendicular to the vertical electric field because of small dielectric constant of the long axis of the LC molecule. Compared with the IPS display mode, the VA display mode has no friction process in a manufacturing process, which increases advantages of manufacturing the LCD device on a large-scale.
The initial VA mode is a multi-domain vertical alignment (MVA) mode, the MVA mode achieves a multi-domain display (generally, four domains) through forming a rib having a predetermined shape on a color film substrate, and the MVA mode improves the viewing angle of the VA mode. However, some defects are generated, the LC molecules in a determined range surrounding the rib have a poor vertical orientation due to the rib on the color film substrate, thus, light leak exists, which affects the contrast ratio of the MVA mode.
With the development of the technology, the MVA technology is improved, and a patterned vertical alignment (PVA) mode is generated. In the PVA mode, a corresponding ITO pattern is formed on a transparent electrode (ITO) of the color film substrate, and the rib is not formed. The pattern may be an ITO slit, and a width of the ITO slit is usually between 8-15 um. The PVA technology does not need to form the rib, and sharply reduces the light leak.
However, other defects are generated in the MAV mode and the PVA mode, transmittances of the rib of the MAV mode and the ITO slit of the PVA mode are far less than transmittance of a normal pixel region, which affects an entire transmittance of the device.
In view of the above-described problems, a new VA mode is generated, and the rib and the ITO slit are not formed on the color film substrate 21 of the new VA mode, which reduces manufacturing cost of the color film and improves the entire transmittance of the device. As shown in FIG. 1A to FIG. 1C, the new VA mode is named as a polymer sustained vertical alignment (PSVA) mode. The color film of the PSVA mode is not only different from the MVA mode and the PVA mode, but also the LC molecule and the pattern of the transparent electrode of the substrate of the PSVA are different from the MVA mode and the PVA mode. In the PSVA mode, a reactive monomer 40 is added into original negative LC molecules 30, and the reactive monomers 40 perform a reaction according to a determined law under an external influence. The width of the transparent electrode 10 and transparent electrode slit 11 are small on transparent electrode pattern of the array substrate 22.
In a manufacturing process of an LCD panel, some LC molecules are remained in an LC bottle. The residual LC molecules should be recycled, purified, and reused, which reduces manufacturing cost. However, the reactive monomer having high-activity is directly added into the LC molecules of the PSVA mode, concentration of the reactive monomer is not easy to manage and the reactive monomer can perform the reaction, thus the LC molecule of the PSVA mode cannot be purified and reused.

PSVA LCD panel and method for manufacturing the PSVA LCD panel

SHENZHEN CHINA STAR OPTOELECTRONICS TECHNOLOGY CO., LTD


A one-piece handle member provided with a bore and a tubular pinion gear fixed to and projecting from a forward end of the handle coaxially with the bore is rotatably mounted on the rearward portion of a single drive shaft against a driven gear fixed coaxially to an intermediate portion of the shaft. A lug member fixed to the intermediate portion of the shaft on the other side of the driven gear projects laterally therefrom and supports a pivot spaced parallel to the drive shaft. First and second transfer gears connected for rotation together are rotatably mounted on the pivot with the first transfer gear permanently meshed with the pinion gear and the second transfer gear permanently meshed with the driven gear. A planar lock member slidably mounted in a slot extending cross-sectionally through the handle has exposed ends used to position the lock member relative to a shaft segment passing through the lock member. In one position the lock member locks the handle to the shaft whereby the shaft turns with the same torque as the handle. In another position the lock member frees the handle for rotation relative to the shaft whereby the gears rotate the shaft a lesser number of degrees than the handle with correspondingly increased torque. A cylindrical retaining ring rotatably secures the shaft to the handle by jamming inside the bore of the handle. In one embodiment a forward portion of the shaft engages the screw; another utilizes detachable screwdriver bits.

1. Field of the Invention
This invention pertains to an improved screwdriver having a single drive shaft rotatably mounted in a one-piece handle member, reduction gearing arranged therebetween, and lock means mounted in the handle member; the lock means being operable, in one position, to lock the handle member to the drive shaft whereby the reduction gearing is bypassed for operation like a conventional screwdriver, and in another position, to permit rotation of the handle member relative to the drive shaft whereby the reduction gearing is operable to increase the torque applied to a screw being turned.
2. Description of Prior Art
A screwdriver, in most common form, comprises a single drive shaft a rearward portion of which is rigidly fixed to a one-piece solid plastic handle and a forward portion of which is shaped to engage a slot-head, philips-head or other type of screw. In another form, the forward portion of the drive shaft is adapted to detachably engage alternative screwdriver bits which differ according to the type of screw head that is to be turned. In either embodiment, the drive shaft turns the same number of degrees as the handle and so the amount of torque that can be applied to the screw is limited according to the strength of the user.
When installing a woodscrew, depending upon the length and diameter of the screw, the hardness of the wood and the size of a pilot hole, if any, substantially increased resistance may be experienced during the last few turns of the screw or during the first few turns when removing such screw. Unexpected resistance may also be experienced when attempting to force a self-tapping screw through a pilot hole that is a little too small. Of course, even for woodscrews, one should provide a pilot hole of correct size, but oftentimes, even when it would seem one has done so, significant resistance may be encountered. At such times, common practice is to grip the screwdriver handle as tightly as possible and force it to turn. This is quickly tiring and even painful, depending upon the size of the screw and how many are being installed or removed. When it can be done without splitting the wood or, in the case of a self-tapping screw, without stripping the screw, a longer screwdriver can be used to apply greater turning force to the screw, but only a moderate mechanical advantage is gained thereby. Many households are fortunate to possess a single screwdriver, typically of medium size, let alone an assortment including an extra-long screwdriver. Even the well-equipped mechanic does not always have exactly the right screwdriver close at hand when needed.
There has long been need for a screwdriver that is adjustable to select an alternative operating mode whereby a greater torque can be applied to the screw than the user is applying to the handle; but, not costing significantly more than a conventional screwdriver, and, without loss of any of the advantages provided by a conventional screwdriver, such as simplicity for durability, compactness and lightness of weight for carrying on one's person or in a tool belt, and an unobstructed view of the screw being turned.
The nearest prior art known comprises U.S. Pat. Nos. 2,721,591, 3,992,964, 4,048,874. 4,846,027 and 5,033,336, which disclose screwdrivers and devices similar thereto wherein gearing is arranged between a handle and an output shaft in order to effect alternative drive ratios therebetween, but in every instance, the disclosed device comprises so many parts that a screwdriver so constructed would cost several times as much as a conventional screwdriver, the price of which determines what the consumer expects to pay for a screwdriver. No prior art is known to disclose a reduction geared screwdriver having such simplicity that it could be manufactured to sell at a price comparable to a conventional screwdriver; which may explain why one does not find reduction geared screwdrivers on display where hand tools are sold and the public has continued to be denied the benefit of such a screwdriver.
The referenced prior art is limited by comprising numerous components including one or more of the following: internally toothed gears cooperating with planetary gears, plural drive shafts or complex linkages ultimately defining a drive shaft, and a handle that either is disclosed as comprising more than one part, or, clearly could not be manufactured to incorporate lock means therein except by construction in plural parts. A further limitation characterizing the referenced prior art is that the reduction gearing is always supported by and concealed within an enclosing cylindrical housing (other than the handle) that, having a diameter greater than that of the handle, further obstructs (beyond that of the gearing itself) the user's view of the screw that is being turned. Reliance upon a housing to support the gearing leads to the further limitations of added weight and bulk, and, because frequently comprising plural parts, to added cost. In order to compete successfully against conventional screwdrivers, a reduction geared screwdriver must be characterized by comparable simplicity for comparable cost, compactness, ruggedness and lightness of weight.
U.S. Pat. No. 3,992,964, listed above and which is entitled "Torquing or Speeding Lug Wrench" is believed to be the closest approach of the prior art. It discloses what is therein termed a "gear box" in the form of a two-part cylindrical housing having parallel spaced apart first and second walls which close opposed ends of the assembled cylindrical housing. A first drive shaft is supported solely by and rotatably secured to the first wall, and a second drive shaft is supported solely by and rotatably secured to the second wall; the two shafts appearing as one because arranged end-to-end, but in fact being distinct members which are rotatable relative to each other. Either one of the shafts may serve as a handle (by connecting a detachable cross-bar thereto) when the other shaft is serving as an output or drive shaft (by connecting a detachable lug-engaging fitting thereto), depending upon whether the device is being used to turn a lug faster (the speeding mode) or to turn a lug with increased torque (the torquing mode). Alternative embodiments are disclosed, one of which, illustrated in FIG. 2 of such patent, shows four gears which are functionally related to each other in the manner of the invention disclosed herein, at least when used in the torquing (or reduction gear) mode. The arrangement disclosed in such patent cannot produce a reduction geared screwdriver comparable in cost and simplicity to a conventional screwdriver or having the other benefits sought to be provided. There are numerous differences, only three of which are pointed out here. First, two drive shafts are involved, instead of one drive shaft as in the present invention. Second, the two drive shafts are independently supported by and independently secured to the gear box; as opposed to the present invention wherein a single drive shaft is supported solely by and rotatably secured to a handle. Third, the use of two, independently rotatable drive shafts, requires that the gear box be held stationary (non-rotatable) during use of the device. For that purpose, the disclosure provides an "extension brace 16" fixed to and extending laterally from the one side of the gear box in order that the free end of such brace will abut the ground and thereby prevent rotation of the gear box when the shaft being used as the handle is being turned. Accordingly, the transfer gears, which are rotatably mounted within and supported by the gear box, have their pivotal axis held stationary with the gear box while a lug is being turned. The present invention provides its transfer gears rotatably mounted and exposed on a pivot that is fixed to the free end of a lug member that revolves with the drive shaft as the screw is being turned; this mode of support of the transfer gears gaining the advantage of minimally obstructing the user's view of the screw being turned, as well as reducing cost, bulk and weight.


Provided is a method for forming a composite barrier layer with superior barrier qualities and superior adhesion properties to both dielectric materials and conductive materials as the composite barrier layer extends throughout the semiconductor device. The composite barrier layer may be formed in regions where it is disposed between two conductive layers and in regions where it is disposed between a conductive layer and a dielectric material. The composite barrier layer may consist of various pluralities of layers and the arrangement of layers that form the composite barrier layer may differ as the barrier layer extends throughout different sections of the device. Amorphous layers of the composite barrier layer generally form boundaries with dielectric materials and crystalline layers generally form boundaries with conductive materials such as interconnect materials.

Barrier layers are commonly used between conductive layers in all kinds of semiconductor devices. Barrier layers can prevent spiking between conductive layers, prevent electromigration failures and generally improve the contact between one conductor and another. Barrier layers are particularly useful and critical in high speed, highly integrated semiconductor devices that use copper as the interconnect material. The conductive interconnect materials of a semiconductor device contact each other through openings formed in insulative dielectric materials that otherwise insulate the various conductive interconnect layers from one another in non-contact regions. The majority of any conductive interconnect feature is therefore bounded by a dielectric, i.e., it forms an interface with the dielectric. When a barrier layer is used in conjunction with a conductive interconnect, it is formed either above or below (or both) the conductive interconnect layer and therefore forms an interface with the insulating dielectric in many areas, as well as an interface with another conductor in the critical contact area. A single barrier layer is therefore disposed between conductors in one area and between one of the conductors and a dielectric, in another area. For example, in single damascene or dual damascene technology, the barrier layer may be formed below the conductor that fills the damascene opening. The barrier layer therefore lines the sides of the opening, interfacing with a dielectric, and is also disposed between two conductors at the bottom of the opening where contact is made to a subjacent conductive material.
Conventional barrier layers typically have strengths and shortcomings. For example, some barrier layers adhere well to conductive materials but do not adhere well to dielectric materials. Conversely, other barrier materials adhere well to dielectric materials but do not adhere well to conductive materials. Some barrier materials provide good barrier qualities with respect to some metals, but not others. In general, barrier layers may include superior or poor qualities with respect to electromigration suppression, contact resistance, wettability, step coverage, resistivity, and so on, depending on where they are used. The reason that a conventional barrier layer typically includes shortcomings in addition to desirable qualities is because conventional barrier layers are typically formed of one barrier material that may provide desirable barrier qualities with respect to some materials but not others. No one barrier material is perfect. For example, if the one barrier material provides superior adhesion to conductive layers, it may conversely provide poor adhesion qualities with respect to dielectric layers. While such an exemplary barrier layer may be a superior barrier material between conductive features, it would likely be deficient when disposed between the conductive material and a dielectric.
It would therefore be desirable to provide a barrier layer, such as a composite barrier layer, having superior qualities for its chosen application. For example, it would be desirable to provide a barrier layer that provides superior barrier qualities and adheres well to all materials it interfaces with throughout the semiconductor device. This invention is directed to such a composite barrier layer.

Method for forming composite barrier layer

Taiwan Semiconductor Manufacturing Company, Ltd.


Methods, computer program products and systems are directed to receiving a query regarding an information architecture, selecting a set of nodes based on the query, from a plurality of nodes in a weighted linked graph, the weighted linked graph comprising the plurality of nodes and a plurality of pathways, each of the plurality of nodes comprising a source of information regarding the information architecture, each of the plurality of pathways connecting one of the plurality of nodes to another of the plurality of nodes, each of the plurality of pathways comprising a weight, determining a path from the plurality of pathways that passes through all of selected nodes, and presenting the path in response to the query.

1. Field
The present invention relates to information architectures, and more specifically, to a semantic questioning mechanism to enable analysis of information architectures.
2. Description of Related Art
Managing information assets, data consumers, and solution architectures is a complex task. Large organizations can have thousands of information sources and consumers interrelated in very complex and poorly defined ways. Related art approaches to understanding the use, interdependencies and relationships of enterprise information assets are deterministic. This means that one only knows what one already knew to ask about. One could track who is using what information sources, if one knows that those information sources exist in the first place. However, this is rarely the case at the enterprise level. The Information Technology (IT) environments of large organizations experience rogue "unofficial" sources of information, partially supported solutions and continued use of deprecated sources.

Semantic questioning mechanism to enable analysis of information architectures

International Business Machines Corporation


A mine scoop machine having a steerable wheeled body provided with a material scoop having a load ejection blade mounted thereon for movement longitudinally of said body between a load position and a load ejection position adjacent an open front end of the scoop, operator controlled power means for moving the ejection blade selectively between the two positions for loading and unloading the scoop, a mine dusting unit mounted on the body rearwardly of the load position of the ejection blade, wherein the dusting unit comprises a dust hopper having a ground rock material feed inlet port and a rock dust outlet port, an air jet means on the unit for fluidizing the ground rock material and ejecting the resulting rock dust out into a mine shaft.

This invention concerns a utility mine scoop machine with mine dusting capability, particularly for use in coal mines. The dusting aspect of the scoop can more effectively provide low levels of dust, e.g., limestone dust, of uniform densities or solids concentrations to the mine ventilation air currents for transportation thereby over substantial distances.
In underground coal mines, large amounts of coal dust are necessarily generated by the cutting, blasting, loading, crushing and the like of the coal. This dust not only is present in high concentrations at these sites but is carried by the mine ventilation air current from these sites, as well as from belt conveyor transfer point and locations along the belt conveyor where ventilation checks are installed, throughout the mines until it settles out on down stream surfaces. Such atmospheric dust, and settled-out dust accumulations are fire and explosion hazards and must be periodically cleaned up or made inert by addition of limestone rock dust.
There are several ways in which underground coal mines generate coal dust, (1) when the coal is cut from the coal seam, (2) when the coal is loaded into equipment that takes the coal to a feeder, (3) when the feeder crushes the coal, (4) when the feeder discharges the coal onto a conveyor belt and, (5) when the coal is discharged from one conveyor belt to the next conveyor belt.
This coal dust is carried by the ventilating air stream into the return ventilation air entries where it settles out in these entries and along the conveyor belt. The dust is also carried along the belt conveyor entries by the air stream in these entries.
Federal law requires that intake entries be 65% inert, and that return entries be 80% inert. Limestone dust is spread in the intake and return entries to get the needed percentages of inertness.
Federal law also does not allow coal dust to remain on top of surfaces underground. For example, an entry could have the percent inertness required but if coal dust is on top of the limestone dust and the entry is black with coal dust, a violation of federal law could be cited.
To keep the return entries and belt conveyor entries white, a limestone distributor called a Trickle Duster is typically employed as shown in U.S. Pat. No. 4,872,598 the disclosure of which is hereby incorporated herein by reference in it entirety. These dusters have an air blower and a tank that holds limestone (rock) dust. The blower discharge air goes into the tank typically up thru the limestone dust and fluidizes the dust. A small portion of the limestone dust is carried by the air stream and is continuously discharged into the entries. The trickle duster discharges a continuous fog of limestone dust that is carried by the ventilation air and helps to keep the return entries and conveyor belt entries white.
With reference to an alternative embodiment of trickle duster, anytime air is taken underground and is warmer than the underground ambient temperature (normally 50-55° F.), a condition of 100% humidity or so is present. In summer months, all surfaces in an underground coal mine are wet. The air that is blown into the limestone dust is at about 100% humidity and the limestone dust absorbs water during its fluidization which causes particles of the dust to become heavier and to stick together. When this limestone dust is discharged into the air stream entries, it will not travel as far and will not uniformly coat surfaces within the mine because it is wet and particles of the dust have agglomerated.
In one preferred embodiment of the present invention, the duster structure is shown in FIG. 1 in cross-section and delivers limestone dust and pressurized air to the mine entries rapidly whereby the dust will only be exposed to the high humidity air from the ambient air from a blower for a short period of time in the delivery hose as compared to prior dusters which are designed to form dust-in-air suspensions within the dust feed hopper apparatus. Employing this duster, limestone dust will travel a greater distance in the entries since it is dry and particles of dust will not be stuck together. This preferred duster employs an auger in the bottom of a vee bottom tank, an air blower and preferably with the addition of a vibrator on at least one sloped side wall to aide in dust movement to the auger and specially designed dust discharge structure which produces a substantially dry dust-in-air discharge stream. By mounting the duster on a battery powered scoop such as shown in FIGS. 5-7, the duster can be transported within the mine, e.g., wherein the mine shaft is only 2 or 3 feet high, by commonly used scoop equipment to any location that the scoop equipment can go. This feature allows for total dust penetration throughout the mine. The motorized structure of the duster preferably is battery operated but can use any power source. Other commonly used dusters can be used, but the one shown in FIG. 1 is preferred.