Abstract: There is provided a system and a method for quantitative measurement of spasticity in a patient. It has been found that stretch reflex measurements, that are quantitatively indicative of spasticity, can be obtained by recording an EMG signal while the limb is being moved at a variety of angular velocities. The method advantageously allows the clinician to perform the test at the bedside by eliminating the need for cumbersome mechanical components for moving the limb while providing quantitative measurements.

Abstract: The invention concerns a drop mass soil compaction apparatus (10, 50) which has a supporting frame (12,64) and a mass (20, 76) which can be raised relative to the frame to an elevated position above a soil surface (40, 61) which is to be compacted. The apparatus includes a mass lifting arrangement for raising the mass to the elevated position such that when the mass is subsequently dropped from such position it impacts on the soil surface in order to compact it. The mass lifting arrangement includes a flexible cable (24, 92) attached to the mass and an hydraulic or pneumatic actuator (36, 68) which is carried by the supporting frame and which acts on the cable in a manner to raise the mass. The cable effectively isolates the mass lifting arrangement, and in particular the actuator, from shock loads generated by impacts of the mass on the soil surface.

Abstract: There is provided a method of measuring properties of a liquid contained in individual wells inside a multi-well array, the method comprising steps of providing capacitor electrodes in the multi-well array, the electrodes adapted to detect a capacitance value of each one of the individual wells without interference of neighboring wells, measuring a capacitance inside each one of the individual wells, and using the capacitance measurements to calculate at least one property of the liquid contained in each one of the individual wells. There is further provided an apparatus for measuring properties of a liquid contained in individual wells inside a multi-well array, and a method of controlling quality of liquid handling task that is repeated across a set of individual wells inside a multi-well array.

Abstract: There is provided a system and a method for quantitative measurement of spasticity in a patient. It has been found that stretch reflex measurements, that are quantitatively indicative of spasticity, can be obtained by recording an EMG signal while the limb is being moved at a variety of angular velocities. The method advantageously allows the clinician to perform the test at the bedside by eliminating the need for cumbersome mechanical components for moving the limb while providing quantitative measurements.

Abstract: An apparatus and method for measuring displacement includes a light beam directed to an interferometer core that splits the light beam into first and second component beams. The first component beam is directed to a diffraction grating at approximately a Littrow angle. A diffraction is received by the interferometer core and is combined with the second component beam. The combination of the first and second component beams is measured to determine displacement of the diffraction grating.

Abstract: A polarization control system includes a light source that generates two light beams with different polarization states and optical frequencies. A polarization state modulator changes the polarization states of the two light beams. A first detector path generates a first beat signal from the two light beams passing through a first polarizer. A second detector path generates a second beat signal from the two light beams passing through a second polarizer that is oriented substantially orthogonal to the first polarizer. An amplitude detector generates an amplitude beat signal from the first and the second beat signals. The system then uses the amplitude beat signal to determine how to adjust the polarization state modulator in order to generate the first and the second light beams with the desired polarization states.

Abstract: At least two discrete quarter wave plates are provided for use as plane mirrors or reflectors in a displacement measuring interferometer, where the plates share common or substantially common reflecting surface geometries. A plurality of geometrically matched discrete matched quarter wave plates reduces the amount of tilt between an input beam provided to, and an output measurement beam provided by, an interferometer, resulting in increased interferometer dynamic range.

Abstract: A photomask and method for maintaining optical properties of the same are disclosed. The method includes providing a substrate including a first surface having an absorber layer formed thereon and a second surface located opposite the first surface. A pattern is formed in the absorber layer to create a photomask for use in a semiconductor manufacturing process. A transmissive protective layer is also formed on at least one of the patterned layer and the second surface of the substrate. The protective layer reduces haze growth when the photomask is used in the semiconductor manufacturing process.

Abstract: Directing an input light beam into a laser diode operated at a power below that required for lasing stimulates emissions, resulting in an amplified output beam. A dynamic steering system can focus the input beam onto front face of the laser diode. The steering system optionally includes an optical element mounted solely on piezoelectric actuators. Control signals for the actuators in the steering system control a base position and cause alternating movements of the optical element. A detector measuring optical power leaking from a back face of the laser diode can determine the power of the amplified beam that exits from the front face, and derivatives of the measured power with respect to the alternating movements indicate required adjustments of the base position. A polarizing beam splitter and quarter-wave plate in the path of beams can separate the input and amplified beams.

Abstract: A polarization control system includes a beam source that generates a first beam component containing light with a first polarization and a first frequency and a second beam component containing light with a second polarization and a second frequency. A polarization state modulator adjusts the polarizations of the components for transmission on a single optical fiber. A detector system measures polarizations of the components when output from the optical fiber and determines how to adjust the polarization state modulator in order to give the first and the second components the desired output polarization states. The beam source can be implemented using a Zeeman-split laser, a laser containing a birefringent element, a pair of phase-locked lasers, and/or a variety of configurations of electro-optic or acousto-optic crystals operated to create or enhance the frequency difference between the beam components.

Abstract: A method for improving polarization extinction ratio includes changing a polarization state of a light beam, wherein the light beam thereafter includes spatially non-uniform polarization states, and spatially filtering the light beam to filter out the spatially non-uniform polarization states. Spatial filtering involves filtering a wavefront of the light beam by passing the light beam through a polarization-maintaining single-mode fiber, or filtering an amplitude of the light beam by passing the light beam through an aperture.

Abstract: The invention concerns a soil compaction roller (10) and a soil compaction machine of which the roller (10) forms part. The roller (10) comprises a multi-sided, out-of-round, peripheral compacting surface (16) which can roll over a soil surface which is to be compacted. The compacting surface (16) is defined by a series of angularly spaced salient points (20) and a corresponding series of compacting faces (22). Each compacting face (22) is outwardly convex in shape and extends continuously between two adjacent salient points (20). When the roller (10) is operative with the compacting surface (16) rolling over the soil surface, the roller rises up on each salient point (20) in turn, storing potential energy, and thereafter rolls downwardly onto the succeeding compacting face (22) to transmit the stored potential energy to the soil surface to compact it.

Abstract: An apparatus for monitoring soil compaction using a compaction machine which applies periodic impact blows to the soil surface. The apparatus comprising a rotatable, multi-sided compactor mass that applies periodic impact blows to the soil surface when rolled over that surface. Data related to the level of compaction of the soil surface is derived, during compaction of the soil surface, from the deceleration of the compactor mass as it impacts the soil surface. This is achieved using one or more accelerometers mounted on the impact compactor.

Abstract: A method of monitoring of the level of compaction of a soil surface undergoing compaction by an impact compactor which includes a rotatable, multi-sided compactor mass that applies periodic impact blows to the soil surface when rolled over that surface. In accordance with the invention, data related to the level of compaction of the soil surface is derived, during compaction of the soil surface, from the deceleration of the compactor mass as it impacts the soil surface. This is achieved using one or more accelerometers mounted on the impact compactor.