11982 results about "Concave surface" patented technology

The invention relates to a surgical implant that provides an artificial diarthroidal-like joint, suitable for use in replacing any joint, but particularly suitable for use as an intervertebral disc endoprosthesis. The invention contains two rigid opposing shells, each having an outer surface adapted to engage the surfaces of the bones of a joint in such a way that the shells are immobilized by friction between their outer surfaces and the surfaces of the bone. These outer surfaces are sufficiently rough that large frictional forces strongly resist any slippage between the outer surface and the bone surfaces in the joint. They may be convex, and when inserted into a milled concavity, are immediately mechanically stable. Desirably, the outer surfaces of the shells are adapted to allow for bony ingrowth, which further stabilizes the shells in place. The inner surfaces of the shells are relatively smooth, and adapted to slide easily across a portion of the outer surface of a central body disposed between the shells. The central body has a shape that cooperates with the shape of the inner surface of the shell so as to provide a range of motion similar to that provided by a healthy joint. A flexible sheath extends between edges of the opposing shells. The inner surface of this sheath, together with the inner surfaces of the rigid shells, defines a cavity encasing the central body. At least a portion of this cavity is filled with a fluid lubricant, further decreasing the frictional force between inner surfaces of the shell and the surface of the central body.

The present invention provides an expandable intervertebral implant that is selectively disposed in the intervertebral space and deployed, thereby in-situ distracting, realigning, and/or stabilizing or fusing a portion of the spine of a patient in the treatment of injury, disease, and/or degenerative condition. The expandable intervertebral implant includes a superior member and an inferior member, each of which has a partially or substantially wedge or prismatic shape and a partially or substantially convex or other-shaped surface that is suitable for engaging the substantially concave surfaces of the associated bony superior and inferior intervertebral endplates. Once disposed in the intervertebral space, the expandable intervertebral implant is actuated and deployed, with the superior member and the inferior member moving apart from one another, seating against the associated intervertebral endplates, and distracting, realigning, and/or stabilizing them to a desired degree. The external surface of each of the superior member and the inferior member is provided with a plurality of ridges or other friction structures, providing purchase with the associated intervertebral endplates.

Disclosed is an ultrasonic surgical instrument that combines end-effector geometry to best affect the multiple functions of a shears-type configuration. The shape of the blade is characterized by a radiused cut offset by some distance to form a curved geometry. The cut creates a curved surface with multiple asymmetries causing multiple imbalances within the blade. Imbalance due to the curve of the instrument is corrected by a non-functional asymmetry proximal to the functional asymmetry. Imbalance due to the asymmetric cross-section of the blade is corrected by the appropriate selection of the volume and location of material removed from a functional asymmetry. The shape of the blade in one embodiment of the present invention is characterized by two radiused cuts offset by some distance to form a curved and potentially tapered geometry. These two cuts create curved surfaces including a concave surface and a convex surface. The length of the radiused cuts affects, in part, the acoustic balancing of the transverse motion induced by the curved shape.

Implantable occlusion devices that include one or more flanges extending from a tubular body are disclosed. The flange or flanges may assist in retention of the device within a vessel, cavity, appendage, etc. At least one flange on the occlusion device may include a concave surface proximate one end of a body. Because of the shape of the flange, e.g., its concavity, the occlusion device may resist dislocation due to e.g., the forces generated within the left atrial appendage during atrial filbrillation.

A method for implanting an intra-articular shoulder prosthesis is provided. The method includes removing a proximal portion of a humerus. The proximal portion of the humerus preferably forms a resected portion. The resected portion has a convex outer surface and an inner surface. The method further includes engaging the convex outer surface of the resected portion with a cut surface of the proximal portion of the humerus. The cut surface of the proximal portion of the humerus and/or the inner surface of the resected portion are optionally processed to form a generally concave surface, such as by impacting. In one embodiment, the inner surface of the resected portion is impacted into engagement with the cut surface of the proximal portion of the humerus. The generally concave inner surface of the resected portion forms a concave articular surface to receive an interpositional implant.

A collimating image-forming apparatus comprising a first linear polarizer is disclosed. A first quarter-wave plate is disposed adjacent the first polarizer and has its fast and slow axes at substantially 45° to the plane of polarization of the first polarizer. The apparatus further comprises a beam-splitting curved mirror having a convex surface adjacent the first polarizer and facing towards the first quarter-wave plate, a second quarter-wave plate adjacent the concave side of the curved mirror, the second quarter-wave plate having its having its fast and slow axes oriented with respect to the corresponding axes of the first quarter-wave plate at angles substantially equal to a first integral multiple of 90°, and a reflective-transmissive polarizing member adjacent the second quarter-wave plate. A second linear polarizer is adjacent the reflective-transmissive polarizing member, the second linear polarizer having its plane of polarization oriented with respect to the plane of polarization of the first linear polarizer at an angle substantially equal to a second integral multiple of 90°, both of the multiples being even or both being odd.

An optical imaging system for pickup, sequentially arranged from an object side to an image side, comprising: the first lens element with positive refractive power having a convex object-side surface, the second lens element with refractive power, the third lens element with refractive power, the fourth lens element with refractive power, the fifth lens element with refractive power; the sixth lens element made of plastic, the sixth lens with refractive power having a concave image-side surface with both being aspheric, and the image-side surface having at least one inflection point. By such arrangements, the optical imaging system for pickup satisfies conditions related to shorten the total length and to reduce the sensitivity for using in compact cameras and mobile phones with camera functionalities.

An antenna system, comprising: a phased array antenna (4); and a dielectric lens arrangement (6), for example a single solid dielectric lens (6) comprising a substantially spherical convex surface (12) and a concave surface (14); wherein the dielectric lens arrangement (6) is arranged to magnify the effective aperture of the phased array antenna (4). The concave surface (14) is positioned within the near field of the phased array antenna (4). The phased array antenna (4) is operated at a frequency greater than or equal to 50 GHz. The antenna system retains some ability to electronically scan the beam. The antenna system may be for transmission and/or reception. The antenna system may be used for example for communication between two vehicles.

A lens and an LED using the lens to achieve homogeneous illumination include a region. The region around the optical axis of a lens is designed to be concave and form a divergent surface. The upper surface of the lens is a continuous curved surface to diverge the high-intensity light emitted by the LED in the vicinity of the optical axis through refractions. Therefore, the LED can homogeneously illuminate a larger area.

An oral care implement including a handle and a head with a tongue cleanser. The tongue cleanser has at least one ridge which is at least as wide as it is high. In one preferred construction, the ridges are shaped so as to define a concave surface facing generally toward the handle. The ridges also preferably include aligned segments from front to back that are oriented at different angular positions.

A lens for a backlight, including: a light transmissive body including outer and inner surface areas, the outer surface area having a convex surface and a concave surface, the inner surface area having a convex surface and a concave surface, wherein the convex surface of the outer surface area has a curvature different from a curvature of the convex surface of the inner surface area and the concave surface of the outer surface area has a curvature different from a curvature of the concave surface of the inner surface area.

A facial mask for filtering ambient air is formed from a pre-form of a multilayer flexible flat filter member of a size to extend over the mouth and nostrils of the user. The flat pre-form filter member can have an ovoid perimeter with an endless band of a hypoallergenic adhesive tape encircling a perimeter of the filter member and operable for sealing with the user's skin to prevent leakage over extended use. Portions of the adhesive tape can self-seal during a sizing step to form structural paths for maintaining a central concavity to ensure a large filtration area offset from the nostrils and mouth of the user. The flexible filter material can further include an activated carbon layer.

A polyaxial bone screw assembly includes a receiver, a shank, an articulation structure for retaining the shank in the receiver and a compression insert for engagement with a longitudinal connecting member such as a rod. The articulation structure includes substantially spherical convex and concave surfaces that slidably engage both shank and receiver surfaces to provide compound articulation between the receiver and the shank. The receiver includes inwardly directed spring tabs engaging the insert and prohibiting rotation of the insert within the receiver.

This invention provides an image capturing lens assembly, in order from an object side to an image side comprising: a first lens element with positive refractive power having a convex object-side surface; a second lens element; a third lens element; a fourth lens element having at least one of an object-side surface and an image-side surface thereof being aspheric; a fifth lens element with positive refractive power having a convex image-side surface, at least one of an object-side surface and the image-side surface thereof being aspheric, and the fifth lens element is made of plastic; and a sixth lens element with negative refractive power having a concave image-side surface, at least one of an object-side surface and the image-side surface thereof being aspheric, and the sixth lens element is made of plastic. By such arrangement, the photo-sensitivity and the total track length of the image capturing lens assembly can be reduced. Furthermore, the aberration and astigmatism of the assembly can be effectively corrected for obtaining higher image resolution.