Ophthalmic lens having morphed sinusoidal phase shift structures
An ophthalmic lens includes an optic comprising an anterior surface, a posterior surface, and an optical axis. At least one of the anterior surface and the posterior surface has a surface profile including a base curvature and a plurality of morphed sinusoidal phase shift structures. The base curvature may correspond to a base optical power of the ophthalmic lens, and the morphed sinusoidal phase shift structures may be configured to extend depth of focus of the ophthalmic lens at intermediate or near viewing distances.
1. An ophthalmic lens, comprising
an optic comprising an anterior surface, a posterior surface, and an optical axis, at least one of the anterior surface and the posterior surface having a surface profile including:
a base curvature; and
a morphed sinusoidal phase shift structure modifying the base curvature along a portion of the surface profile, wherein the morphed sinusoidal phase shift structure comprises a plurality of morphed sinusoidal phase shift zones, wherein each of the plurality of morphed sinusoidal phase shift zones comprises a single sinusoidal period;
wherein the morphed sinusoidal phase shift structure is configured to extend depth of focus of the ophthalmic lens as compared to an unmodified portion of the base curvature;
wherein the surface profile is defined as:
Z optic ( r )= Z base ( r )+ Z MSPS ( r )
wherein Z base (r) defines the base curvature that is aspheric; and
Z MSPS (r) defines the plurality of morphed sinusoidal phase shift zones;
Z
MSPS
(
r
)
=
M
i
T
i
P
π
(
1
-
cos
(
r
-
R
i
T
i
P
π
)
)
,
R
i
≤
r
<
R
i
+
T
i
P
Z
MSPS
(
r
)
=
M
i
T
i
P
π
(
1
-
cos
(
r
-
R
i
-
T
i
P
R
i
+
1
-
R
i
-
T
i
P
π
+
π
)
)
,
R
i
+
T
i
P
≤
r
<
R
i
+
1
r denotes a radial distance from the optical axis in units of (mm);
R i and R i+1 are starting and ending radial positions from the optical axis of each zone in units of (mm);
M i are step heights of each zone in units of (μm);
T i P are critical points corresponding to a radial distance of a peak of each zone from the starting radial position of the zone; and
i indicates zone numbers i=0, 1, 2, 3 . . . , consecutively from the optical axis.
2. The ophthalmic lens of claim 1 , wherein the base curvature corresponds to a base optical power of the ophthalmic lens.
3. The ophthalmic lens of claim 1 , wherein the morphed sinusoidal phase shift structure is configured to extend depth of focus of the ophthalmic lens to provide intermediate or near viewing distances in the range of 30-55 cm.
4. The ophthalmic lens of claim 1 , wherein the morphed sinusoidal phase shift structure is configured to extend depth of focus of the ophthalmic lens to provide intermediate or near viewing distances in the range of 33-50 cm.
5. The ophthalmic lens of claim 1 , wherein the morphed sinusoidal phase shift structure comprises at least seven morphed sinusoidal phase shift zones.
6. The ophthalmic lens of claim 1 , wherein the ophthalmic lens comprises an intraocular lens.
7. The ophthalmic lens of claim 1 , wherein the ophthalmic lens comprises a contact lens.
8. The ophthalmic lens of claim 1 , wherein:
Z
base
(
r
)
=
cr
2
1
+
1
-
(
1
+
k
)
c
2
r
2
+
a
2
r
2
+
a
4
r
4
+
a
6
r
6
+
a
8
r
8
+
a
10
r
10
and:
r denotes a radial distance from the optical axis in units of (mm);
c denotes a base curvature of the surface;
k denotes a conic constant;
a 2 , a 4 , a 6 , a 8 , and a 10 are, respectively, second, fourth, sixth, eighth, and tenth order coefficients.