Abstract: This invention adds a non-linear sweep accumulator to the conventional sigma-delta fractional-N divider to produce a N.F value that is a polynomial function of time. This allows any non-linear sweep profiles to be approximated.

Abstract: A digital color processing method for images from scanners and digital cameras processes image data suitable for display on monitors or color hardcopies produced by digital color printers and correct hue shift and incorrect exposure based on the image content. The method automatically corrects the data based on the histogram of the acquired image normalizing the image data to correct for the hue shift and determining the gamma parameter to correct the exposure of the image.

Abstract: The focal length of an acoustic ultrasound transducer is made variable by shaping the focusing element positioned over the transducer. The focusing means consists of a non-uniform focusing element whereby the transducer can be manipulated either electronically or mechanically to optimize the depth of focus for the area of interest.

Abstract: A miniature rotatable sensor include an acoustic face positioned over a layer of attenuating material. Between the acoustic face and the attentuating material is a flexible circuit that contacts the acoustic face and has circuit edge that extend beyond the attenuating material to create an inner portion. The inner portion further includes a radial slot extending throught the perimeter of the attenuating material. The circuit edges are folded into the radial slot such that the flexible circuit exits tangential to the diameter of the sensor.

Abstract: A laser interferometer measurement system eliminates detection of "false" zero crossings in the measurement signal. The measurement signal is shifted in phase by an integrator or a differentiator. The positive portion of the shifted measurement signal is used to determine falling portions of the measurement signal while the negative portion of the shifted measurement signal is used to determine the rising portions of the measurement signal. Each portion is compared to the reference signal. A SR latch receives the result of each comparator. The output signal of the SR latch reflects the zero crossings of the measurement signal without the effects of noise.

Abstract: Active thermal conduction of a transducer array at the distal end of an imaging probe maintains the temperature of the transducer array below a predetermined limit so as not to damage human body tissue. A thermally conductive rotor is connected between the back face of the transducer array and a stator that behaves as a heat sink. A dual ball bearing arrangement is placed near the rotor/stator interface to allow rotation of the transducer array while providing thermal conduction. An optional layer of oil may be placed between the rotor and the stator to promote heat transfer.

Abstract: A figure-8 loop laser having a controllable phase shifter in a Sagnac loop (non-linear amplifying loop mirror). A half-wave plate in series with Faraday optical rotators provide a switchable non-reciprocal 180-degree phase shifter that allows the birefringence of the fiber loop to be adjusted during continuous wave operation. The phase shifter is activated during continuous wave operation to find a minimum threshold and then is turned off, placing the laser in optimum state for mode locking.