Abstract: A head-mounted display may include a display system and an optical system in a housing. The display system may have displays that produce images. Positioners may be used to move the displays relative to the eye positions of a user's eyes. An adjustable optical system may include tunable lenses such as tunable cylindrical liquid crystal lenses. The displays may be viewed through the lenses when the user's eyes are at the eye positions. A sensor may be incorporated into the head-mounted display to measure refractive errors in the user's eyes. The sensor may include waveguides and volume holograms, and a camera for gathering light that has reflected from the retinas of the user's eyes. Viewing comfort may be enhanced by adjusting display positions relative to the eye positions and/or by adjusting lens settings based on the content being presented on the display and/or measured refractive errors.

Abstract: A display system includes a display panel configured to emit a polarized image light having a first polarization state and at least one emission spectrum having a full width at half maxima (FWHM). The display system includes a reflective polarizer configured to receive and reflect the polarized image light as a first reflected polarized image light. For a first light incident at a first predetermined angle, the reflective polarizer has an average reflectance of greater than about 60% across the at least one emission spectrum for the first polarization state, a transmittance of at least about 50% for at least wavelength outside the FWHM of the at least one emission spectrum for the first polarization state, and an average total transmittance of greater than about 70% across a visible wavelength range including the FWHM of the at least one emission spectrum for an orthogonal second polarization state.

Abstract: An endodontic instrument of this disclosure has less torque strength but greater flexibility and enlarged chip space compared to the prior art. In embodiments. only two flutes are spiraled about the instrument's length L to form two non-landed cutting edges between D2 and D16, the cutting edges merging to form a land at about D1. The tip end is rounded. The helical angle ? increases from the handle end toward the tip end, a number of spirals per unit length being at least two times greater toward the tip end than toward the handle end, a cross-section of the length L consisting of two convex portions intersecting at each cutting edge or a wave-shape having one concave portion and one convex portion intersecting at each cutting edge, the cross-section occupying less total area than would a same size endodontic instrument having a triangular cross-section and providing greater chip space.

Abstract: An endodontic instrument of this disclosure has less torque strength but greater flexibility and enlarged chip space compared to the prior art. In embodiments. only two flutes are spiraled about the instrument's length L to form two non-landed cutting edges between D2 and D16, the cutting edges merging to form a land at about D1. The tip end is rounded. The helical angle ? increases from the handle end toward the tip end, a number of spirals per unit length being at least two times greater toward the tip end than toward the handle end, a cross-section of the length L consisting of two convex portions intersecting at each cutting edge or a wave-shape having one concave portion and one convex portion intersecting at each cutting edge, the cross-section occupying less total area than would a same size endodontic instrument having a triangular cross-section and providing greater chip space.

Abstract: A solution for evaluating the condition of a vehicle component based on resonant response profiles across a set of bands of vibrations. The vibrations can be induced into the target component during normal operation of the target component. The resonant response profile of the vehicle component can vary depending on wear or damage, and thus can be used to determine whether the vehicle component can safely remain in use. An embodiment comprises an isolated segment of rail of a length selected to allow a single railroad wheel on it at a time, with a set of devices which can induce specific vibrations into the wheel as it passes, and another set of devices which can acquire the resonance signals from the wheel.

Abstract: An improved rotary endodontic file includes a multi-planar pre-curved apical portion having a first and a second curvature. The pre-curved apical portion begins at about one-third to one-quarter of the working length as measured from the tip end of the endodontic instrument. The first and second curvature permit the file to continually search and engage the walls of a tooth root canal in a forced inside-forced outside manner. As the file works its way down, it breaks free of any ledges encountered, probes lateral- and delta-type openings, and does not allow the file to stray from the curvature of the canal.

Abstract: A rotary cutting tool has a cutting body and a plurality of cutting inserts, including a first insert removably secured in a first pocket and a second insert removably secured in a second pocket. The first pocket opens out at a forward end surface of the cutting body, having a seat surface with an axial support wall transverse thereto, and the second pocket is located axially rearward of the first pocket. The first insert has opposing front and back end surfaces, with a peripheral side surface extending therebetween which is in contact with the seat surface and the axial support wall. A first major cutting edge of the first insert axially overlaps with a second major cutting edge of the second insert, and in a side view of the cutting tool, a raised shoulder surface adjacent the axial support wall is at least partially obscured by the second insert.

Abstract: A cutting insert has opposing front and back end surfaces with a peripheral side surface extending therebetween and a first axis extending therethrough, and a median plane perpendicular to the first axis located between the front and back end surfaces. Each of the front and back end surfaces has a rectangular shape in a respective end view thereof, and two diagonally opposed raised corners and two diagonally opposed lowered corners with respect to the median plane. The front end surface has a front major cutting edge associated therewith, and in a cross-section taken in a first plane containing the first axis, the front end surface has a concave shape and the back end surface has a convex shape. The cutting insert is removably secured in an insert receiving pocket of a cutting tool with the peripheral side surface and back end surface making contact with pocket support walls.

Abstract: A rotary cutting tool has a cutting body and a plurality of cutting inserts, including a first insert removably secured in a first pocket and a second insert removably secured in a second pocket. The first pocket opens out at a forward end surface of the cutting body, having a seat surface with an axial support wall transverse thereto, and the second pocket is located axially rearward of the first pocket. The first insert has opposing front and back end surfaces, with a peripheral side surface extending therebetween which is in contact with the seat surface and the axial support wall. A first major cutting edge of the first insert axially overlaps with a second major cutting edge of the second insert, and in a side view of the cutting tool, a raised shoulder surface adjacent the axial support wall is at least partially obscured by the second insert.

Abstract: A cutting insert has opposing front and back end surfaces with a peripheral side surface extending therebetween and a first axis extending therethrough, and a median plane perpendicular to the first axis located between the front and back end surfaces. Each of the front and back end surfaces has a rectangular shape in a respective end view thereof, and two diagonally opposed raised corners and two diagonally opposed lowered corners with respect to the median plane. The front end surface has a front major cutting edge associated therewith, and in a cross-section taken in a first plane containing the first axis, the front end surface has a concave shape and the back end surface has a convex shape. The cutting insert is removably secured in an insert receiving pocket of a cutting tool with the peripheral side surface and back end surface making contact with pocket support walls.

Abstract: A fatigue-resistant Nitinol instrument has a working portion in the deformed monoclinic martensitic state and an austenite finish temperature in the range of 40° to 60° C. Because the operating environment of the instrument is about 37° C., the working portion remains in the monoclinic martensitic state during its use. The relatively high austenite finish temperature and fatigue resistance is achieved by subjecting the nickel-titanium alloy to a final thermal heat treat in a temperature range of about 410° to 440° C. while the nickel-titanium alloy is under constant strain of about 3 to 15 kg. Further, the high austenite finish temperature is achieved without subjecting the alloy to thermal cycling to produce shape memory. Additionally, there are no intermediate processing steps occurring between obtaining a finished diameter of the wire or blank through cold working and the final thermal heat treat under constant strain.

Abstract: A composite membrane and moisture adjustment module using the same is disclosed. The composite membrane includes a moisture-permeable resin layer interposed between porous membranes that constitute a pair; and the mean thickness of the moisture-permeable resin layer is 5 ?m or less.

Abstract: A self-healing composite membrane includes a continuous ionomer phase in which is dispersed a plurality of hollow fibers and/or microcapsules each containing a liquid healing agent that includes a dispersion or solution of a healing ionomer in a liquid vehicle. Electrochemical devices employing the self-healing composite membranes are provided.

Abstract: A solution for evaluating the condition of a vehicle component based on resonant response profiles across a set of bands of vibrations. The vibrations can be induced into the target component during normal operation of the target component. The resonant response profile of the vehicle component can vary depending on wear or damage, and thus can be used to determine whether the vehicle component can safely remain in use. An embodiment comprises an isolated segment of rail of a length selected to allow a single railroad wheel on it at a time, with a set of devices which can induce specific vibrations into the wheel as it passes, and another set of devices which can acquire the resonance signals from the wheel.

Abstract: A solution for evaluating the condition of a rail component based on resonant response profiles across a set of bands of vibrations. The vibrations can be induced into the target component during normal operation of the target component. The resonant response profile of the rail component can vary depending on wear or damage, and thus can be used to determine whether the rail component can safely remain in use. An embodiment comprises an isolated segment of rail of a length selected to allow a single railroad wheel on it at a time, with a set of devices which can induce specific vibrations into the wheel as it passes, and another set of devices which can acquire the resonance signals from the wheel.

Abstract: A solution for evaluating the condition of a rail component based on resonant response profiles across a set of bands of vibrations. The vibrations can be induced into the target component during normal operation of the target component. The resonant response profile of the rail component can vary depending on wear or damage, and thus can be used to determine whether the rail component can safely remain in use. An embodiment comprises an isolated segment of rail of a length selected to allow a single railroad wheel on it at a time, with a set of devices which can acquire the resonance signals from the wheel.

Abstract: An improved rotary endodontic file includes a multi-planar pre-curved apical portion having a first and a second curvature. The pre-curved apical portion begins at about one-third to one-quarter of the working length as measured from the tip end of the endodontic instrument. The first and second curvature permit the file to continually search and engage the walls of a tooth root canal in a forced inside-forced outside manner. As the file works its way down, it breaks free of any ledges encountered, probes lateral- and delta-type openings, and does not allow the file to stray from the curvature of the canal.

Abstract: A composite membrane and moisture adjustment module using the same is disclosed. The composite membrane includes a moisture-permeable resin layer interposed between porous membranes that constitute a pair; and the mean thickness of the moisture-permeable resin layer is 5 ?m or less.

Abstract: An improved rotary endodontic file includes a multi-planar pre-curved apical portion having a first and a second curvature. The pre-curved apical portion begins at about one-third to one-quarter of the working length as measured from the tip end of the endodontic instrument. The first and second curvature permit the file to continually search and engage the walls of a tooth root canal in a forced inside-forced outside manner. As the file works its way down, it breaks free of any ledges encountered, probes lateral- and delta-type openings, and does not allow the file to stray from the curvature of the canal.

Abstract: A functional TFE copolymer fine powder is described, wherein the TFE copolymer is a polymer of TFE and at least one functional comonomer, and wherein the TFE copolymer has functional groups that are pendant to the polymer chain. The functional TFE copolymer fine powder resin is paste extrudable and expandable. Methods for making the functional TFE copolymer are also described. The expanded functional TFE copolymer material may be post-reacted after expansion.