B24B13/0052

METHOD FOR GENERATING SETTINGS FOR MACHINING AN OPTICAL LENS
20180284728 · 2018-10-04 ·

Disclosed is a method for generating settings for machining an optical lens, including: a) acquiring a file characterizing the shape to which the optical lens must be machined in order to allow it to be mounted in a spectacle frame; b) decomposing the shape into a plurality of distinct objects, including an exterior envelope inside of which all the other objects are located; c) determining a machining order of the other objects; and d) generating the machining settings depending on the machining order.

Method of minimal stress inducing ophthalmic lens blocking

A method and associated implementing system eliminates much of the stress presently introduced by the bonding of ophthalmic lens blanks, or blanks to a holding device, namely a metal block. The method of attaching ophthalmic lens blanks to a blocking assembly comprises the steps of shaping a blocking assembly to take the shape of an ophthalmic lens blank surface of an ophthalmic lens, wherein the blocking assembly is not attached directly to the ophthalmic lens blank during shaping of the blocking assembly; and following the shaping of the blocking assembly, attaching the lens blank to the shaped blocking assembly.

Method And Apparatus For Manufacturing Contact Lens Moulds

A collet (230) for holding a contact lens mold half (240) during machining of a surface of the mold half (240) comprises a disc (235) having a face and defining: a central structure (250a), at the centre of the face, for receiving a head portion (240a) of the mold half (240), and an elongate recess (250b), in the face, for receiving a tail portion (240b) of the mold half (240), the elongate recess (250b) extending from the central structure (250a) along a radius of the disc (235).

Blocking device for a semi-finished optical element

The blocking device includes a blocking portion configured for blocking the semi-finished optical element and including a support member configured for providing a rigid support to the semi-finished optical element, the support member including a support element made of a shape-memory material having a rigid state below a predetermined temperature and a plastic state above the predetermined temperature, the support element assuming in the absence of external forces a predetermined memory shape when heated above the predetermined temperature, the support member having a contact face onto which the first face of the semi-finished optical element is to be applied; saind blocking portion including at least one of a heating device configured for heating the support element above the predetermined temperature and a cooling device configured for cooling the support element below the predetermined temperature.

METHODS AND APPARATUS FOR INSPECTION AND OPTIONAL REWORK OF BLOCKED OPHTHALMIC LENSES

An opaque adhesive can be used to secure the convex surface of a lens blank to a lens blocking piece. This opaque adhesive can include a resin that is curable under ultraviolet light and contains many dispersed pigment particles. The pigment particles may absorb light in the wavelength range of about 300 nm to about 800 nm such that the adhesive appears substantially opaque. A lens-on-block (LOB) system that uses the opaque adhesive to adhere a lens blank to a lens blocking piece facilitates on-block inspection of surface defects by increasing the contrast of light reflected from the surface being inspected. Put differently, the defects in the lens blank's surfaces stand out more when viewed in front of the opaque adhesive The inspection results can be used to carry out rework loops that eliminate or correct the detected defects, providing a streamlined method for on-block manufacturing of ophthalmic lenses.

EDGING PAD HAVING DIFFERENT ADHESIVE ZONES
20170173753 · 2017-06-22 ·

The invention relates to an edging pad for releasably connecting a material blank that is to be edged to a holder, wherein the edging pad has a polymeric carrier layer and adhesive coatings which are applied to both sides of the polymeric carrier layer, wherein one side of the polymeric carrier layer, which is to be connected to the holder, has an adhesive coating formed of a first adhesive, and the other side of the polymeric carrier layer, which is to be connected to the material blank, has an adhesive coating formed of a second and a third adhesive which are different from one another, such that the second adhesive provides adhesiveness to the material blank and the third adhesive is an adhesive which limits twisting and slippage of the polymeric carrier layer relative to the material blank, wherein the second adhesive and the third adhesive are applied to the other side of the polymeric carrier layer in separate regions.

Optical element blocking method and related device

A method for blocking an optical element on an insert of a blocking device including: providing the insert of the blocking device, the insert being blocked in respect with the blocking device; providing thermoplastic material in a solid state in a first particulate form, the provided thermoplastic material having a feature included in an operating range; heating at least a part of the provided thermoplastic material at a temperature at which the thermoplastic material is in a melted state and flows under moderate pressure; providing on the insert an amount of the heated thermoplastic material for blocking one optical element; placing the optical element onto the thermoplastic material in the melted state; allowing the thermoplastic material to solidify, thereby blocking the optical element on the insert; converting the solidified thermoplastic material into a second particulate form, the converted thermoplastic material being intended to block another optical element.

Block mold and apparatus for blocking a lens

An apparatus and a block mold for blocking a lens are proposed, wherein the lens is blocked on a block piece by means of a block material. The space between the lens and the block piece is laterally delimited by a block mold. The block mold is preferably plate-shaped and has a plurality of block openings for forming different block sizes and has an integrated coolant channel. This enables easy and fast changing between different block sizes and very good cooling.

Mandrel for use in the machining of ophthalmic lenses

A mandrel 1 for holding an ophthalmic lens member blank 52 during machining is disclosed. The mandrel 1 comprises a front surface 6 for receiving an ophthalmic lens member blank 52 to be machined; a rear surface 8 opposite the front surface 6; and one or more through-holes 10 extending between the front and rear surfaces 6,8. In use, wax applied to the rear surface 8 contacts an ophthalmic lens member blank 52 received on the front surface 6 via said one or more through-holes 10. Methods of producing an ophthalmic lens using such a mandrel and lenses produced using such a mandrel are also disclosed.