Each tool comprises a molded head and a cylindrical shank for supporting the tool in a surfacing machine. In one embodiment the head is semi-spherical in configuration, and a plurality of metal inserts are embedded in the head so that a circular recess, which is formed in one end of each insert to hold a lens blank, opens on the spherical surface of the head with its axis extending through the center of curvature of the head and the axis of the tool shank. In another embodiment the head contains...

A set of ophthalmic lens prism blocking rings is disclosed wherein each prism blocking ring comprises a substantially circular annulus adapted to be detachably connected between an ophthalmic lens to be ground and a blocking body. The annulus has a flat lower annular surface and a first thickness at one end of a diameter and a second thickness at the other end of the diameter and defines an inclined plane therebetween. The angle of incline corresponds to the amount of prism to be introduced into...

A support for a glass blank, e.g. a telescope mirror blank, while a surface of the blank is being ground. The support comprises a blocking body and a plurality of spaced, flexible tubes extending in a parallel pattern over the blocking body surface. At least some of the tubes are filled with an organic material that is cured to form a rigid polymer support. A second set of tubes under air pressure from an air manifold may provide an initial support for the blank while the first set of tubes is b...

A chucking method and apparatus for processing a lens blank in a manner requiring only a single mounting of the blank to an associated lens block. The lens block is mounted to the convex lens blank surface by a hot melt type of adhesive so as to extend outwardly thereof substantially coaxial with the lens blank frame center axis. The lens blank and lens block are releasably mounted in a chuck associated with lens surface generating apparatus such that the lens blank frame center axis and the tai...

A lens block having locating bosses for fixturing to lens-surfacing equipment and an interconnected oppositely disposed lens holding portion all cast of a eutectic blocking medium. The blocking medium is cast over and through an apertured preform of rigid, relatively high melting temperature material functioning as a heat sink and material filler.

The pneumatic blocking support which is used to block an optical lens (200) on a machine or device has means (3) for fixing it on a corresponding element of the machine or device. The blocking means comprise a central cavity (8) and a joint (9) having at least one annular part (9) against which the lens rests in order to define a depression chamber (11) with said cavity and joint. The blocking elements include stop members (10) which are created in order to provide the optical lens with a rigid ...

A variable pitch lapping block for use in polishing a range of prescription lenses having different radii of curvatures is obtained by the use of an element made of rubber or the like, which is associated with a pressurized chamber, wherein the element exhibits a range of curvatures depending upon the variation of the pressure in the chamber.

There is disclosed a block piece for holding an optical workpiece, in particular a spectacle lens, for machining thereof, which block piece comprises a basic body which has an end face, against which the workpiece can be blocked by means of a temporarily deformable material, and a clamping face via which the workpiece blocked on the basic body can be fixed on a spindle of a machining machine. According to the invention, the basic body is injection-molded from plastic and is provided on its end f...

A hand tool for polishing the tip of a fiber optic terminal. The tool includes a base having a central opening that receives a collet through which the fiber optic terminal extends. The fiber optic terminal is gripped by the collet as a collet spring force is exerted on the collet. An axial force is applied to the collet as the base rests on a polishing surface, the force being established by a piston spring that maintains the tip of the fiber optic terminal in contact with the polishing surface...

The present invention provides novel preformed base blocks that may be used with thermoplastic ophthalmic lens blocking compositions. The preformed base block has a rear portion that is sized and adapted to fit the chuck of a lens processing machine and a front portion that has a negatively tapered peripheral edge. The front portion is adapted to mechanically retain the thermoplastic blocking composition to form a lens block against a lens blank.