Abstract: An apparatus for non-contact measurement of particles, fibers and other light scattering elements includes two laser beams that intersect one another to form a measuring region within a composite flow. Particles in the flow scatter the laser energy as they traverse the measuring region. Scattered energy is received by a pair of optical detectors that generate respective electrical signals based on received energy. The detectors have selectively contoured non-rectangular apertures to controllably vary transmittance and as a result generate phase differences according to a corresponding non-linear function that relates the phase differences to particle diameters. One particularly effective aperture shape includes opposite sides contoured according to a lognormal function, to resemble an onion or tear drop. Triangular and trapezoidal apertures also can be used to achieve non-linear functions.

Abstract: An atherectomy device includes a catheter with a window at its distal tip for admitting tissue into a catheter compartment. A cylindrical cartridge in the compartment has a cutting edge that supports an electrically conductive cutting element, e.g. a band or wire. The cutting element and adjacent tissue can be heated to a selected temperature by generating an electrical current through the cutting element. The catheter is maneuverable to position its distal end near a lesion in an artery. The catheter incorporates a dilatation balloon or other feature to urge the catheter against the lesion, so that at least part of the lesion enters the compartment through the window. Then, the cartridge is manipulated from the catheter's proximal end to move the cutting edge across the window, severing the acquired tissue. According to alternative embodiments, the cartridge is either rotated or moved axially relative to the catheter, in either event closing the catheter window when the cut is complete.

Abstract: An exhaust system, including a hand-held exhaust wand is employed to remove laser smoke plumes generated at a surgical site. The wand includes a transparent cylindrical shroud containing a conical filter that diverges in the proximal direction. An adapter, removably coupled to the shroud at its proximal end, enables coupling of the wand to standard vacuum tubing, connectors and other components for exhausting air that flows through the wand. The wand is positioned with its distal end confronting the surgical site, whereby plumes and odor generated at the site are immediately drawn into the wand through its distal opening. As air passes through the filter toward a proximal opening of the wand, the conical filter traps the airborne contaminants to protect against contamination of downstream components. The removable coupling of the shroud enables convenient exchange of the filter.

Abstract: A liquid recycling and filtering system is well suited for use in continuous flow recycling surface cleaning devices. The system employs a canister containing a liquid cleaning solution, and a cylindrical filter submerged in the liquid and defining a chamber containing a portion of the liquid. A liquid supply conduit withdraws liquid from the chamber and supplies the liquid to a cleaning tool head, where the liquid is sprayed upon a floor or other surface being cleaned. A counterflow conduit is coupled to the liquid supply conduit and to the chamber, for transporting liquid under pressure to a spraying assembly within the chamber. The spraying assembly includes a rotatable manifold and nozzles at opposite ends of the manifold. The nozzles spray the liquid in planar, fan-shaped patterns that impinge upon the filter over limited surface areas.