| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an improved multifocal ophthalmic lens. <P>SOLUTION: 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 so 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 so 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. <P>COPYRIGHT: (C)2012,JPO&INPIT |
