摘要 |
A selectably transmissive internally focused intermediate image lens and a lens based optical window include a number of such lenses. Each selectably transmissive internally focused intermediate image lens in a lens based optical window includes a first and second lens portion. The first lens portion receives light and focuses it into a focused image at a focal plane that is coplanar with a second side of the first portion. A second lens portion has an image side adjacent to the second side of the first lens portion and an opposite side opposite the image side. The second lens portion refracts the focused image as an image projected through its rear side. Each lens further includes a selectably transmissive shutter that is located at the internal focal plane and that is controllable to block at least a portion of light passing therethrough. |