The invention provides a method producing contact lenses, comprising the step of: separating the mold into the male and female mold halves, with the silicone hydrogel contact lens adhered on one of the male and female mold halves; bring a shaped ultrasonic horn in direct contact with at least one area of a non-optical surface of the female mold half or the male mold half having the molded silicone hydrogel contact lens attached thereon; and applying a ultrasonic vibrational energy to the at least one area of the non-optical surface of the female mold half or the male mold half having the molded silicone hydrogel contact lens attached thereon so as to separate the molded silicone hydrogel contact lens from the mold half attached thereon.

Apparatuses and methods for multistage molding of contact lenses containing low oxygen permeable components or oxygen impermeable components. Components may be embedded within a contact lens by forming a device on a polymer substrate, molding a spacer onto a male mold, bonding the device to the spacer, removing the polymer substrate, and molding the remainder of the contact lens.

A de-taping machine for removing a tape around a lens-mold-assembly. The machine including a lens-mold-assembly-rotation mechanism for holding and rotating the lens-mold-assembly and a tape gripping mechanism. The tape gripping mechanism including a first jaw having a clamping surface; a second jaw movable towards the first jaw for clamping a free end of the tape; a proximity sensing arrangement to generate a first detection signal when the free end of the tape is at a pre-determined distance from the first jaw; and a contact sensing arrangement to generate a second detection signal when the tape is in contact with the first jaw. A rotational speed of the lens-mold-assembly-rotation may be varied based on the first detection signal. Further, the lens-mold-assembly-rotation mechanism may be stop and the tape gripping mechanism may move the second jaw for clamping based on the second detection signal. A corresponding method for tape removal.

The invention provides a method for making silicone hydrogel contact lenses in a relatively efficient and consistent manner from a lens formulation (i.e., a polymerizable composition) including a thermal initiator having a 10-hour half-life temperature (T.sub.10hλ) under a controlled thermal curing scheme. A method of the invention comprises a step of curing the lens formulation in an oven according to a thermal curing profile that comprises or consists essentially of increasing the oven's temperature from room temperature or a temperature that is at least about 5° C. lower than T.sub.10hλ to a temperature that is at least 30° C. higher than T.sub.10hλ at a selected rate (e.g., from about 1° C./minute to about 10° C./minute). Under such a controlled thermal curing scheme, the lens diameter of the fully-hydrated silicone hydrogel contact lenses obtained according to a method of the invention does not vary significantly with the positions of the molds in the oven.

A shell removal device includes a platform configured to secure a mold. An untrimmed shell is formed over the mold. The shell removal device further includes a drive mechanism configured to move the platform away from the untrimmed shell responsive to sensor data indicative that the untrimmed shell has begun to separate from the mold.

In manufacturing a contact lens, a contact lens mould arrangement in which the engagement between the mould halves is unconstrained and at least one mould half is sufficiently pliable or flexible that during the curing of the contact lens composition at one mold half may move or flex relative to the other to define a post-cure mould cavity of smaller volume than the precure mould cavity and during which the curvatures of the first and/or second mould surfaces are allowed to change provides a significantly more efficient manufacturing process and enables one mould half to be readily utilized as a blister cup for contact lens packaging.

The invention provides a contact lens manufacturing method for cast-molding of silicone hydrogel contact lenses having enhanced oxygen permeability without adversely affecting desirable lens mechanical properties (e.g., modulus). A method of the invention comprises adding a small amount of a radical scavenger (e.g., H-TEMPO) in a polymerizable composition for cast-molding of SiHy contact lenses) to provide the resultant polymerizable composition with a bi-phase curing profile at a curing temperature of from about 45° C. to about 100° C. With such a bi-phase curing profile, the resultant polymerizable composition can be thermally cured at the curing temperature to form a SiHy contact lens having an oxygen permeability higher than that for a polymerizable composition having the substantially identical composition excepting being free of any radical scavenger.

The present invention generally relates to a method for producing silicone hydrogel contact lenses having less optical defects or free of optical defects by subjecting the extraction tray for the formed silicone hydrogel contact lenses to a reciprocating lowering and raising motion thereof to obtain the silicone hydrogel contact lenses.

Embodiments relate to automating removal of an untrimmed shell from a mold. In one embodiment, a shell removal device includes a body and a platform disposed within the body. The platform is configured to secure a mold that has an untrimmed shell formed over the mold. The shell removal device further includes a cover configured to secure the untrimmed shell to an upper surface of one or more sidewalls of the body and provide a seal between a lower surface of the untrimmed shell and the upper surface of the one or more sidewalls of the body. The shell removal device may include a media inlet in the body to permit pressurized media into the interior of the body to cause a pressure differential between an upper surface of the untrimmed shell and the lower surface of the untrimmed shell to cause the untrimmed shell to release from the mold.

Described herein is a method for producing a contact lens comprising a central zone that has a diameter of about 13 mm or less, is concentric with the central axis of the contact lens, and possesses at least one photo functionality. The method comprises: applying a first polymerizable fluid composition containing at least one photochemically functional compound on a central portion of the molding surface of a female mold half to form a circular layer; partially curing, in situ, the circular layer in the female mold half; dispensing a second polymerizable fluid composition over the partially-cured circular layer on the molding surface of the female mold half; and a step of curing the second polymerizable fluid composition and the partially-cured circular layer immersed therein in the mold cavity formed between the the molding surfaces of the female mold half and a male mold half.