| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical magnifier whose eye relief is at least great to the same extent as the EFL of a lens for a micro display. SOLUTION: A magnifying lens has a first positive power meniscus element in which at least one face is an aspheric face and a second positive power lens element which has an aspheric object side surface being convex toward the object side and an observing eye side surface and at least one of the object side surface of the first positive power meniscus element and the observing eye side surface of the second positive power element is diffraction property. At least two of the aspheric surfaces can be simple conics. This optical magnifier suitable for use in an electronic display system has the apparent field of view of at least±10 degrees, a magnification of at least 15 times, a back focal length of at least 5 millimeters, and an eye relief greater than the effective focal length of the magnifier. The lens elements are made of plastic. COPYRIGHT: (C)2004,JPO&NCIPI
|
