Films having asymmetric grin optical elements for application to spectacles or other ophthalmic lenses
A film ( 1 ), an ophthalmic lens including a film ( 1 ), spectacles comprising an ophthalmic lens including a film ( 1 ), and a method of manufacturing a film ( 1 ) are described. The film ( 1 ) has a base refractive index and includes at least one gradient index optical element ( 7 a, 7 b ) having an asymmetric refractive index profile.
1. A film for applying to an ophthalmic lens, wherein the film has a base refractive index and includes at least one gradient index optical element having an asymmetric refractive index profile, wherein the film is configurable on a surface of a lens, such that light from a distant point source on the optical axis of the lens that passes through a region of the film having the base refractive index is focused towards a point on the optical axis of the lens, and light from a distant point source on the optical axis of the lens that passes through the at least one gradient index optical element is focused towards a point that is a first distance from the optical axis.
2. The film according to claim 1 , including a plurality of the gradient index optical elements distributed randomly across the film.
3. The film according to claim 1 , wherein at least two of the gradient index optical elements have the same asymmetric refractive index profile.
4. The film according to claim 1 , wherein at least two of the gradient index optical elements have different asymmetric refractive index profiles.
5. The film according to claim 2 , said film including a plurality of gradient index optical elements arranged to form at least one annular ring, wherein the at least one annular ring is centred on a film axis that extends in a direction substantially perpendicular to the plane of the film.
6. The film according to claim 5 , including a plurality of gradient index optical elements arranged to form at least two concentric annular rings, wherein the concentric annular rings are centred on the film axis.
7. The film according to claim 5 , wherein gradient index optical elements that form part of the same annular ring have the same refractive index profile.
8. The film according to claim 1 , wherein gradient index optical elements forming a first annular ring have a first refractive index profile gradient index optical elements forming a second concentric annular ring have a second, different refractive index profile.
9. The film according to claim 1 , wherein each of the at least one gradient index optical elements has a diameter or width of between 1 μm and 5 mm.
10. The film according to claim 1 , wherein the gradient index optical elements occupy between 20% and 80% of a surface area of the film.
11. The film according to claim 1 , wherein the film is a photopolymer film, and wherein each of the at least one gradient index optical elements is a photocured gradient index optical element.
12. The film according to claim 1 , wherein each of the at least one gradient index optical elements has a refractive index profile defined by an asymmetric polynomial function.
13. The film according to claim 1 , the film having a thickness of between 1 μm and 70 μm.
14. The film according to claim 1 , further comprising an adhesive surface for adhering the film to a surface of an ophthalmic lens.
15. The film according to claim 1 , further comprising a substrate configured to provide a protective layer when the film is applied to a surface of an ophthalmic lens.
16. The film according to claim 1 , said film further comprising at least one annular ring of gradient index optical elements, wherein the film is configurable on a surface of a lens such that light from a distant point source on the optical axis of the lens that passes through a region of the film having the base refractive index is focused towards a point on the optical axis of the lens, and light from a distant point source on the optical axis of the lens that passes through the at least one annular ring of gradient index optical elements forms an annular ring of focal points at a focal surface.
17. An ophthalmic lens including the film of claim 1 .
18. The ophthalmic lens of claim 17 , said ophthalmic lens is a spectacle lens.
19. The ophthalmic lens of claim 17 , said ophthalmic lens is a contact lens.
20. Spectacles comprising the ophthalmic lens of claim 17 .
21. A method of manufacturing the film according to claim 1 , the method comprising:
providing a photocurable film; and
using a digital light projection system to photocure at least one region of the film, thereby producing at least one photocured gradient index optical element having an asymmetric refractive index profile.