Abstract: A method and apparatus for measuring relative humidity including condensing environmental conditions using a circuit with a capacitive humidity sensor and a reference resistor each connected to an input of a switch device and thence a quadrature sampling circuit. A sinusoidal source is first connected to the reference resistor and secondly to the capacitive humidity while a signal ground is first connected to the capacitive humidity sensor and secondly to the reference resistor. This produces a first voltage and a second voltage that are each sampled in quadrature. A complex ratio of the sampled voltages is calculated and converted into a representation of relative humidity.

Abstract: A method and apparatus for measuring relative humidity including condensing environmental conditions using a circuit with a capacitive humidity sensor and a reference resistor each connected to an input of a switch means and thence a quadrature sampling circuit. A sinusoidal source is first connected to the reference resistor and secondly to the capacitive humidity while a signal ground is first connected to the capacitive humidity sensor and secondly to the reference resistor. This produces a first voltage and a second voltage that are each sampled in quadrature. A complex ratio of the sampled voltages is calculated and converted into a representation of relative humidity.

Abstract: An apparatus having a shaft that can sense the depth of penetration, for penetrating into an object (the substrate). The substrate being penetrated has impedance that varies according to the depth under a surface of the substrate. The shaft has a tip for penetration and has conductive ends near to the tip of the shaft. A change of impedance of material of the object between the conductive ends can be sensed to provide information on the depth of penetration. A processor can be provided external to the object being penetrated by the shaft to gather and process the impedance information to determine whether the desired depth has been achieved.

Abstract: Disclosed herein are devices for altering gaseous flow within a lung to improve the expiration cycle of an individual, particularly individuals having Chronic Obstructive Pulmonary Disease (COPD). More particularly, devices are disclosed to produce collateral openings or channels through the airway wall so that expired air is able to pass directly out of the lung tissue to facilitate both the exchange of oxygen ultimately into the blood and/or to decompress hyper-inflated lungs.

Abstract: The present invention provides a medical device, or medical navigator, based not on a programming perspective, but a use perspective. Medication to be taken is displayed on a color screen, actual size where possible. A color display is used because the pharmaceutical industry worldwide has substantially standardized on the colors; e.g., black and yellow pills mean barbiturates. Capsules and caplets are uniquely colored for the medicines. Pharmacists can readily tell what the medication is by looking at it. And, patients identify medications by their color and size. Input mechanisms are provided for indicating compliance with the mediation schedule and the physical condition of the patient.

Abstract: The effect of ultrasound irradiation of a human or other animal body portion is enhanced by operating the body portion as a trapped mode resonator. The intensity and location of resonances within the body portion is controlled by controlling such variables as the amplitude, frequency and/or phase of the ultrasound irradiation. This minimizes the overall energy required to be applied to the body portion in order to achieve a desired localized intensity level.

Abstract: An apparatus having a shaft that can sense the depth of penetration, for penetrating into an object (the substrate). The substrate being penetrated has impedance that varies according to the depth under a surface of the substrate. The shaft has a tip for penetration and has conductive ends near to the tip of the shaft. A change of impedance of material of the object between the conductive ends can be sensed to provide information on the depth of penetration. A processor can be provided external to the object being penetrated by the shaft to gather and process the impedance information to determine whether the desired depth has been achieved.

Abstract: A system and a method of objectively assessing the functional status of a subject utilize a functional status scale to extract objective measures that are indicative of the subject's functional status. The objective measures are extracted from center-of-weight (C.O.W.) data gathered from the functional status scale when the subject is standing on the scale. These objective measures can then be used to assess the current functional status of the subject by a health care provider. The functional status scale can be remotely stationed at the subject's home, which eliminates the need for office visits, expensive home nurse visits, telephone interviews or video visits to assess the current functional status of the subject. The functional status scale includes weight sensors that are connected to a C.O.W. computer. The C.O.W. computer is configured to compute x and y coordinates of the C.O.W. from weight signals generated by the weight sensors.

Abstract: A sensor for sensing in a gas stream a vapor of a liquid. The sensor includes a micropore and a wet temperature sensor. The micropore has an evaporation end and has a lumen to conduct liquid from a supply of the liquid for evaporation at the evaporation end. The wet temperature sensor has a heat sensitive part in contact with the liquid in the micropore. The heat sensitive part circumscribes the micropore and forms part of the lumen. Heat loss due to evaporation of the liquid when the wet temperature sensor wet with the liquid is placed in the gas stream will result in the temperature sensed by the wet temperature sensor being lower than the non-evaporative temperature of the gas stream. This lowering in temperature can be measured to determine the concentration of the vapor in the gas stream. An example of such a sensor has a thermocouple junction having micropores passing through the thermocouple junction.

Abstract: A sensor for sensing in a gas stream a vapor of a liquid. The sensor includes a micropore and a wet temperature sensor. The micropore has an evaporation end and has a lumen to conduct liquid from a supply of the liquid for evaporation at the evaporation end. The wet temperature sensor has a heat sensitive part in contact with the liquid in the micropore. The heat sensitive part circumscribes the micropore and forms part of the lumen. Heat loss due to evaporation of the liquid when the wet temperature sensor wet with the liquid is placed in the gas stream will result in the temperature sensed by the wet temperature sensor being lower than the non-evaporative temperature of the gas stream. This lowering in temperature can be measured to determine the concentration of the vapor in the gas stream. An example of such a sensor has a thermocouple junction having micropores passing through the thermocouple junction.

Abstract: A direct contact scanner uses a fiber acoustic waveguide to convey ultrasound from an ultrasound transducer to a direct contact area. The waveguide extends from a main body of the scanner into an oblong nose, and terminates in a deflector. To minimize thickness of the nose, the waveguide and deflector are rotated about an ultrasound transmission axis of the waveguide, enabling the scanner to be used in a variety of situations where quarters are cramped. A coupling fluid conveys ultrasound between the deflector and a radome, which directly contacts the object to be scanned. Using the waveguide, an ultrasound transducer and supporting electronics may be distanced from the direct contact area and separated from the fluid, thereby insulating the fluid from possible electronic leakage currents and heat.

Abstract: A system and a method for remote monitoring of a designated user utilize an integrated scale that is able to measure the body weight of a current user and determine whether the current user is the designated user. The identification of the current user is accomplished by measuring a preselected length of the current user by reflecting sound waves at location(s) that defines the preselected length and comparing the measured length to a corresponding length of the designated user that is stored in the integrated scale. When the current user is identified as the designated user, the integrated scale transmits the measured body weight to a remote monitoring device. The preselected length may be the distance from the bottom of a foot to the knee joint. Alternatively, the preselected length may be the length of a tibia or femur, or the skeletal height.

Abstract: A motion detection scheme is described which periodically sends a plurality of pulsed ultrasonic signals from a transducer to a particular range cell to receive a series of backscattered signals from the particular range cell. The time interval between any two pulses is greater than a largest dimension of the range cell divided by a slowest velocity of motion at the particular range cell. A temporal variation between the envelopes of the signals is then determined to detect motion at the particular range cell. This scheme may be applied at all points in an image, to produce images that depict regions undergoing motion.

Abstract: A laser system capable of providing light of high intensity is disclosed. This system includes a laser gain medium and three reflectors. A first reflector and a second reflector spaced from the first reflector define a laser cavity that contains the laser gain medium. The second reflector has a reflectivity (R.sub.2) larger than the reflectivity (R.sub.1) of the first reflector such that light emitted from the laser gain medium resonates in the laser cavity. A third reflector having a reflectivity (R.sub.3) larger than the reflectivity of the first reflector (R.sub.1) is spaced from the second reflector to define a resonant cavity external to the laser cavity. Light passes from the laser cavity to resonate in the external resonant cavity. Part of the light passes from the external resonant cavity to the laser cavity to optically lock the laser gain medium. The distance between the second and the third reflectors is adjustable to tune the resonant frequency of the external cavity.

Abstract: A method and apparatus for coupling ultrasonic energy into a clad or unclad waveguide include using phased array techniques to increase the area and intensity of radiation into the waveguide. An array of ultrasound transducers is positioned at the exterior of the waveguide and at dissimilar distances from the end of the waveguide. The transducers are individually fired by applying separate phase-shifted excitation signals. The phase shifting achieves a selected phase-differential relationship with respect to signals applied to adjacent transducers. The selected phase-differential relationship defines an angle of radiation into the waveguide. In the preferred embodiment, the apparatus is a medical device, such as an angioplasty device or ultrasound imaging device.

Abstract: Piezoelectric elements in a transducer array are individually excited and used to sense the back-scattered signal from fluid flowing within an interrogation volume. The array is preferably a 2-D phased array with a pitch no greater than one-half the acoustic wavelength of the interrogation signal. By activating the transducer elements as a pattern of concentric rings as viewed from a point of interrogation, and by suitable phasing and range-gating of an interrogation signal, a substantially spherical interrogation volume (SIV) is created. The return signal from the SIV provides an isotropic indication of the speed of flow of the fluid. The focussing distance along an interrogation axis can be changed by changing either the size of the aperture created by the pattern of activated elements or their relative phasing. The interrogation direction can be angled off-axis by activating the transducer elements in a pattern of concentric ellipses.

Abstract: An ultrasound system and method for intravascular ultrasonic imaging includes an array of beacons that are fixed to direct ultrasonic energy toward an imaging transducer, with individual beacons being identifiable in order to determine the angular position of the imaging transducer. Based upon the data related to beacon identification, operation of the imaging device is adaptively adjusted in order to compensate for variations in angular velocity of the transducer. Adaptive compensation may be performed by adjusting the pulse repetition rate of transmitted ultrasonic energy, by adjusting the scan conversion algorithm or mapping reflected ultrasonic energy, or by varying control of the drive structure for rotating the transducer. The beacons are preferably piezoelectrically active, but passive beacons may also be used. Position identification may be performed by techniques including amplitude sensing, phase sensing, pulse length sensing, and frequency sensing.

Abstract: A method and system of monitoring performance of a heart include echocardiographic transmission and reception to form time series of frames containing mean squared difference data. Mean squared signal change, mean squared speed or root mean squared speed may be used to form functional images, such as average speed over a selected time interval or peak speed over a selected time interval.

Abstract: A method and system for monitoring performance of a heart includes forming a time series of frames of echocardiographic data. The time series may be for a systolic interval, but longer intervals are also possible. The frames of the time series have sets of corresponding data points with respect to specific sites of a patient's heart. For each set of corresponding data points, a time domain signal as a function of a selected scalar is determined, thereby yielding a time domain signal which varies with frame-to-frame variations of the selected scalar. The scalar has a physiological significance to the contractile state or the motion of the myocardium. Mean squared speed, root mean squared speed, mean squared rate of signal change, integrated backscatter, correlation area, and echocardiographic signal data magnitude are suitable scalars. For each time domain signal, a phase angle is obtained to assign a pixel value to an image data point.

Abstract: Spherical annulus piezoelectric transducers 62, 64 and spherical disc piezoelectric transducer 66 form a spherical shell having a radius of curvature R with a focal point 70 near the end of cladded-core acoustic waveguide 72. Each transducer 62, 64, 66 generates a bulk acoustic wave of a unique frequency and transmits it to focal point 70 where it enters core 74 of cladded-core acoustic waveguide 72. Alternatively, a conical annulus piezoelectric transducers 92, 116 on a prism 90 generate bulk acoustic waves of multiple discrete frequencies and focus them through cladding 75 and into core 74 of cladded-core acoustic waveguide 72. Surface acoustic waves of multiple discrete frequencies can be generated by multiple sets of curvilinear interdigital conductors 132, 134 on a piezoelectric substrate 122. The shape of curvilinear interdigital conductors 132, 134 focuses the surface acoustic waves at focal point 70 located near the end of acoustic waveguide 72.