High reliability varifocal electrostatic lens
A varifocal lens includes a substrate having an inclined region, a primary electrode disposed over the inclined region of the substrate, a dielectric layer disposed over the primary electrode, a deformable membrane disposed over and at least partially spaced away from the dielectric layer, a secondary electrode disposed over a surface of the deformable membrane facing toward or away from the dielectric layer and overlying at least a portion of the primary electrode, and a fluid between the membrane and the substrate, wherein a surface of the dielectric layer facing the secondary electrode comprises a textured surface.
1. A varifocal lens comprising:
a substrate having an inclined region;
a primary electrode disposed over the inclined region of the substrate;
a dielectric layer disposed over the primary electrode;
a deformable membrane disposed over and at least partially spaced away from the dielectric layer;
a secondary electrode disposed over a surface of the deformable membrane facing toward or away from the dielectric layer and overlying at least a portion of the primary electrode;
a hydrophilic layer disposed over the secondary electrode, the hydrophilic layer facing the dielectric layer; and
a primary fluid between the deformable membrane and the substrate, wherein:
the primary electrode and the secondary electrode have variable geometries that enable the primary electrode and secondary electrode to control, in response to an applied voltage, a shape of the deformable membrane.
2. The varifocal lens of claim 1 , wherein the inclined region is located peripheral to an optically active area of the lens.
3. The varifocal lens of claim 2 , further comprising a secondary fluid located outside of the optically active area.
4. The varifocal lens of claim 3 , wherein the secondary fluid is in fluid communication with the primary fluid.
5. The varifocal lens of claim 1 , wherein a slope of the inclined region varies as a function of position.
6. The varifocal lens of claim 1 , wherein the primary electrode is bonded to the inclined region of the substrate.
7. The varifocal lens of claim 1 , wherein the deformable membrane is bonded to the substrate.
8. The varifocal lens of claim 1 , wherein the secondary electrode is bonded to at least one portion of at least one surface of the deformable membrane.
9. The varifocal lens of claim 1 , wherein a surface of the dielectric layer facing the secondary electrode comprises one or more fluid channels.
10. The varifocal lens of claim 1 , wherein a thickness of the deformable membrane varies with position.
11. The varifocal lens of claim 1 , further comprising an elastic spacer located between the primary electrode and the secondary electrode.
12. The varifocal lens of claim 1 , further comprising a barrier coating disposed over at least one surface of the deformable membrane.
13. The varifocal lens of claim 1 , further comprising a hydrophobic layer disposed over the dielectric layer facing the secondary electrode.