| 摘要 |
<p>A real image viewfinder with an objective having movable focusing lens(es) and a field lens at the end thereof furtherest from the field of view, an eyepiece lens and image inverting optics, preferable in the form of a Type II Porro prism wherein the real image is focused to fall on a surface of the field lens, which is desirably a plano surface facing the inverting optics. This field lens surface is also at the focus of the eye piece lens. A pattern (a reticle) is located on the field lens surface. Since the objective forms a focus at the location of the reticle, observation of the reticle indicates when the objective is focused. A camera picture taking lens may be coupled to a movable lens in the objective for focusing the taking lens.</p> |
