Abstract: The present invention relates to a handheld, point-of-care device that uses non-hazardous low level ultrasound to quantitatively detect, monitor and supply, in real time, information on the status of bone fractures from inception to full healing. The device includes a plurality of transducers housed in the handheld unit or which can be extended from the handheld unit to be placed at or near the site of the bone fracture. A plurality of acoustic parameters of the transducers are selected to provide optimal detection and monitoring of fractures in bone. The information can be displayed as a numerical readout indicating the severity of the break and provides ability for indicating small stress and fatigue fractures. The portable device provides rapid and inexpensive detection and diagnosis of musculoskeletal problems using low level ultrasound which can measure bone density, determine fracture status and monitor healing rate.

Abstract: An ultrasound imaging system employs acoustic impedance reconstruction to produce high-resolution images of anatomical structures, which are virtually free of speckle. Determination of the acoustic impedance profile involves prefiltering of the incident ultrasound signal and the ultrasound signal reflected from the specimen to be imaged. A time domain window function is applied to both the incident and reflected signals, and an N-point FFT is computed for both the digitized incident and reflected signals to obtain the incident and reflected spectrums. A complex division of the reflected spectrum by the incident spectrum is performed to obtain the transfer function. A window function having a sharp, low-frequency cutoff is applied to the transfer function prior to performing an inverse FFT to obtain the estimated impulse response.

Abstract: A frequency deviation meter provides a display of the error in a timepiece's internal oscillator, and includes a plurality of pickup devices among which are electrostatic and ultrasonic detectors. Frequency of the timepiece's oscillator and the frequency error is displayed as seconds lost or gained per month. An elongated aluminum alloy resonant column of tool stock material having a crystal pickup provides a sensitive vibration detector assembly.