OBJECTIVE LENS SYSTEM, RELAY LENS SYSTEM, AND EYEPIECE LENS SYSTEM FOR NIGHT-VISION GOGGLES

摘要

The goggles (20, 120) include a pair of optical assemblies (40, 140) each having two intersecting optical paths, including a see-through path with a large field of view of a straight line of sight to the viewed object, and a folded path which includes an objective lens set (50, 150) an intensifier (60) which converts visible and infrared light to a visible intensified light, and an eyepiece lens set (70, 170) arranged in a loop in a plane perpendicular to the see-through path. Infrared and visible light from the viewed objected enters both paths. A dichroic prism combiner (46, 141) at the intersection of the paths reflects intensified light from the folded path into the see-through path and transmits all other light. In one embodiment a dichroic prism separator (42) is disposed at the intersection of the paths forward of the combiner for transmitting a portion of the incoming visible light along the see-through path and reflecting the remainder of the incoming light to the folded path. In another embodiment, the entrance to the folded path is spaced from the see-through path.