US Patent 7481532 Pseudo-accommodative IOL having multiple diffractive patterns

In one aspect, a trifocal ophthalmic lens is disclosed that includes an optic having a surface that comprises at least one trifocal diffractive pattern and at least one bifocal diffractive pattern such that the bifocal pattern provides near and far vision and the trifocal pattern generates near, far, and intermediate vision. For example, the trifocal pattern can provide near, far, and intermediate foci such that the near and far foci are substantially coincident, respectively, with a near and a far focus of the bifocal pattern. In this manner, the trifocal and bifocal patterns collectively provide near, intermediate, and far foci (or focal regions) corresponding, respectively, to the near, intermediate and far vision.