Abstract:
A method for avoiding the entrapment of air bubbles (5) in a lens forming material, in particular in a low viscosity lens forming material, in an ophthalmic lens manufacturing process using mold halves (2; 3) each having a lens forming surface (21; 31) comprises electrostatically charging a predetermined portion of the lens forming surface (21; 31) of the mold half (2; 3) prior to the predetermined portion of the lens forming surface (21; 31) coming into contact with the lens forming material (4).
Abstract:
There are described a method for applying a coating to a surface of an ophthalmic lens mold. The mold includes male and female (20) mold halves, with each of the mold halves being provided with a lens forming surface (21). The method includes applying a temporary coating to at least a portion of at least one of the male and female mold halves (20), the temporary coating being capable of reducing adhesive forces between a lens forming material and the lens forming surface (21); and drying the temporary coating applied to the portion of the lens forming surface (21). Also described is a device (1) for applying such temporary coating to the portion of the lens forming surface (21) of the ophthalmic lens mold.
Abstract:
A method of cleaning deposited material from a molding surface (10) of a mold (1) for forming ophthalmic lenses, including bringing a cleaning head (20) into contact with the molding surface (10), the rotational axis (22) of the cleaning head (20) being arranged normal to the molding surface (10), rotating (220) the cleaning head (20) around the rotational axis (22) while maintaining the contact between the cleaning head (20) and the molding surface (10), moving the cleaning head (20) to perform a precession motion (110) around a central normal (11) on the molding surface (10), while rotating (220) the cleaning head (20) around the rotational axis (22) and while maintaining the contact between the cleaning head (20) and the molding surface (10). During the precession motion (110) the rotational axis (22) includes an inclination angle (α1,α2) with the central normal (11) on the molding surface (10).
Abstract:
There are described a method for applying a coating to a surface of an ophthalmic lens mold. The mold includes male and female (20) mold halves, with each of the mold halves being provided with a lens forming surface (21). The method includes applying a temporary coating to at least a portion of at least one of the male and female mold halves (20), the temporary coating being capable of reducing adhesive forces between a lens forming material and the lens forming surface (21); and drying the temporary coating applied to the portion of the lens forming surface (21). Also described is a device (1) for applying such temporary coating to the portion of the lens forming surface (21) of the ophthalmic lens mold.
Abstract:
A method of cleaning deposited material from a molding surface (10) of a mold (1) for forming ophthalmic lenses, including bringing a cleaning head (20) into contact with the molding surface (10), the rotational axis (22) of the cleaning head (20) being arranged normal to the molding surface (10), rotating (220) the cleaning head (20) around the rotational axis (22) while maintaining the contact between the cleaning head (20) and the molding surface (10), moving the cleaning head (20) to perform a precession motion (110) around a central normal (11) on the molding surface (10), while rotating (220) the cleaning head (20) around the rotational axis (22) and while maintaining the contact between the cleaning head (20) and the molding surface (10). During the precession motion (110) the rotational axis (22) includes an inclination angle (α1,α2) with the central normal (11) on the molding surface (10).
Abstract:
A method for cleaning a molding surface (51) of a reusable lens mold (5), in particular of a reusable lens mold (5) for molding ophthalmic lenses such as soft contact lenses, comprising the steps of: generating a jet (3) of deionized water, exposing the molding surface (51) of the reusable lens mold (5) to the jet (3) of deionized water, wherein the jet (3) of deionized water has a circular full cone spray pattern and impinges on the molding surface (51) of the reusable lens mold (5), and wherein the circular full cone spray pattern has a uniform distribution of the volume flow of deionized water over the base of the cone of the circular full cone spray pattern.
Abstract:
A method of cleaning deposited material from a molding surface (10) of a mold (1) for forming ophthalmic lenses, including bringing a cleaning head (20) into contact with the molding surface (10), the rotational axis (22) of the cleaning head (20) being arranged normal to the molding surface (10), rotating (220) the cleaning head (20) around the rotational axis (22) while maintaining the contact between the cleaning head (20) and the molding surface (10), moving the cleaning head (20) to perform a precession motion (110) around a central normal (11) on the molding surface (10), while rotating (220) the cleaning head (20) around the rotational axis (22) and while maintaining the contact between the cleaning head (20) and the molding surface (10). During the precession motion (110) the rotational axis (22) includes an inclination angle (α1,α2) with the central normal (11) on the molding surface (10).
Abstract:
A method for avoiding the entrapment of air bubbles (5) in a lens forming material, in particular in a low viscosity lens forming material, in an ophthalmic lens manufacturing process using mold halves (2; 3) each having a lens forming surface (21; 31) comprises electrostatically charging a predetermined portion of the lens forming surface (21; 31) of the mold half (2; 3) prior to the predetermined portion of the lens forming surface (21; 31) coming into contact with the lens forming material (4).
Abstract:
A method for determining residual moisture on and/or within a lens forming surface of a mold half includes the steps of carrying out an infrared inspection of at least a central portion of the lens forming surface of the mold half with the aid of an infrared camera, collecting measurement values resulting from the infrared inspection, which represent a degree of residual moisture on and/or within the lens forming surface, comparing the collected measurement values with a predefined threshold value representing a maximum tolerable residual moisture on and/or within a lens forming surface of a reference mold half, and, upon detection of an exceedance of the predefined threshold value representing the maximum tolerable residual moisture, preventing the inspected mold half from being used further.
Abstract:
A method for cleaning a molding surface (51) of a reusable lens mold (5), in particular of a reusable lens mold (5) for molding ophthalmic lenses such as soft contact lenses, comprising the steps of: generating a jet (3) of deionized water, exposing the molding surface (51) of the reusable lens mold (5) to the jet (3) of deionized water, wherein the jet (3) of deionized water has a circular full cone spray pattern and impinges on the molding surface (51) of the reusable lens mold (5), and wherein the circular full cone spray pattern has a uniform distribution of the volume flow of deionized water over the base of the cone of the circular full cone spray pattern.