Process for manufacturing an intraocular lens with an embedded mask
Intraocular implants and methods of making intraocular implants are provided. The intraocular implant can include a mask adapted to increase depth of focus. The method of manufacturing the implant can include positioning the mask with an aperture on a protruding pin of a positioning mold portion. The protruding pin can be configured to center the mask in the intraocular lens.
1. A method of manufacturing an intraocular lens, the method comprising:
adding a first amount of a lens material to a first lens forming mold portion;
positioning a mask with an aperture on a protruding pin of a positioning mold portion such that the protruding pin extends into the aperture of the mask, the protruding pin being configured to center the mask in the intraocular lens;
joining the first lens forming mold portion and the positioning mold portion; and
partially curing the first amount of the lens material;
wherein the positioning the mask on the protruding pin comprises positioning the mask adjacent to a shoulder portion of the protruding pin having a diameter larger than the aperture of the mask, the shoulder portion being configured to control the depth of the mask in the intraocular lens.
2. The method of claim 1 , wherein the lens material comprises an ultraviolet light absorber and a light-sensitive initiator, the light-sensitive initiator being configured to cure the lens material when exposed to light having a wavelength outside the absorption spectrum of the ultraviolet light absorber.
3. The method of claim 2 , wherein the light-sensitive initiator is configured to be activated by light having a wavelength in a range from about 380 nm to about 495 nm.
4. The method of claim 1 , wherein joining the first lens forming mold portion and the positioning mold portion causes lens material to flow into a space between a surface of the mask and an inner surface of the positioning mold portion from which the protruding pin extends so as to at least partially surround the mask with lens material on both of its sides.
5. The method of claim 1 , wherein partially curing the first amount of the lens material comprises applying light to the first lens forming mold portion.
6. The method of claim 1 , wherein partially curing the first amount of the lens material comprises curing the first amount of the lens material less than 50% of a full cure but to a sufficient degree that the mask remains with the first lens forming mold portion after removing the positioning mold portion.
7. The method of claim 1 , further comprising cooling the first lens forming mold portion.
8. The method of claim 1 , further comprising removing the positioning mold portion and joining the first lens forming mold portion and a second lens forming mold portion.
9. The method of claim 8 , further comprising adding a second amount of the lens material to the second lens forming mold portion.
10. The method of claim 9 , further comprising partially curing the second amount of the lens material less than 50% of a full cure by exposure to light.
11. The method of claim 10 , further comprising, after partially curing the second amount of the lens material by exposure to light, thermally curing the second amount of the lens material.
12. The method of claim 11 , further comprising polymerizing at least 99% of the first and second amounts of the lens material.
13. The method of claim 1 , wherein the lens material is a hydrophobic material.
14. The method of claim 1 , further comprising joining a haptic shield and the positioning mold such that the haptic shield prevents polymerization of the lens material in a haptic region.
15. The method of claim 1 , wherein the protruding pin extends from an interior surface of the first lens forming mold portion.
16. The method of claim 1 , wherein the protruding pin is transversely centered in a cavity of the first lens forming mold portion.