Flood lamp with improved light energy utilization

摘要

A flood light includes a lamp that is located at a focus of a reflecting mirror having a reflecting surface whose cross-section is oval and partially arcuate. A concave lens having negative refracting power is disposed between first and second foci about which an elliptical reflecting surface of the reflecting mirror is disposed. Some light rays from the lamp pass directly from the lamp through the lens while other rays from the lamp are reflected by the mirror before passing through the lens. Generally speaking, on the upstream side of the lens, the reflected rays enter the lens outboard of the rays that pass directly from the lamp to the lens. This construction provides a small flood light that has a high optical output, and effectively uses bundles of rays emitted from the lamp to produce a luminous intensity distribution desirable as light for range finding.