Lens having an optical add power progression
An apparatus, system and method including an ophthalmic lens having an optic with an anterior surface, a posterior surface, and an optical axis. The ophthalmic lens further includes a first region having a first optical power and a second region having a second optical power. The ophthalmic lens further includes a third region having an optical power that progresses from the first optical power to the second optical power. The progression may be uniform or non-uniform. Each of the first, second and progression optical power may include a base power and an optical add power. Each of the first, second and progression regions may provide a first focus, a second focus and a plurality of third foci, respectively.
1. An ophthalmic lens, comprising:
an optic with a regional power distribution comprised of:
a first region having a first optical power, being a base optical power or a sum of a base optical power and a first optical add power for providing a first focus;
a second region having a second optical power, being a sum of the base optical power and a second optical add power different from the first optical add power for providing a second focus; and
a third region having at least the base optical power and a plurality of third optical add powers forming the progression of optical add powers from the first optical add power to the second optical add power,
wherein the second region has a first boundary at an interface with the third region and a second boundary opposite the first boundary, and
wherein the second region has the second optical power at the first boundary and the second boundary.
2. The lens of the claim 1 , where the progression is fitted as an extended asphere.
3. The lens of the claim 2 , wherein a curvature and conic constant of the base power is used for the progression fitting.
4. The lens of the claim 3 , wherein the curvature and conic constant used for the progression fitting are different to that defining the base optical power.
5. The lens of the claim 1 , wherein the surface is defined as an extended asphere in a progression direction and a standard asphere in an orthogonal direction.
6. The lens of the claim 5 , wherein the extended asphere and the standard asphere are defined by a same curvature and conic constant.
7. The lens of the claim 5 , wherein the extended asphere and the standard asphere are defined by a different curvature and conic constant.
8. The lens of the claim 1 , wherein the surface is defined as an extended asphere in x and y directions.
9. The lens of the claim 8 , wherein the curvature and conic constant is the same for both directions.
10. The lens of the claim 8 , wherein the curvature and conic constant is different for both directions.
11. The lens of claim 1 , wherein the regional power distribution is applied vertically.
12. The lens of claim 1 , wherein the regional power distribution is applied horizontally.
13. The lens of claim 1 , wherein the regional power distribution is applied both vertically and horizontally.