| 摘要 |
A variable-power lens includes first and second lens elements one behind the other along an optical axis of the lens. Each element has opposed planar and curved surfaces such that the thickness of each element in a direction parallel to the optical axis varies in a direction transverse to the optical axis. The elements are relatively moveable in the transverse direction, whereby the power of the lens may be varied. The elements are arranged such that the curved surface of the first element is adjacent the second element and the planar surface of the first element bears a diffractive pattern. |
