摘要 |
A contact lens comprising a corneal section, a vertical axis, and a shape adapted to maintain the lens at an intended orientation. The lens has either a visible horizontal line segment located in the corneal section perpendicular to the vertical axis and/or three visible radial line segments in the corneal section, the first of the line segments located on the vertical axis, and the second and third segments located on either side of the first segment such that the extensions of the segments would pass through a geometric center of the corneal section forming two 20 DEG angles. The lens is useful for measuring the rotation of an asymmetric lens. Methods for measuring lens rotation using the inventive lenses are also disclosed.
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