Binocular night glass

Claim 1

A binocular night glass for both infrared and visible light, comprising an image converter including a series arrangement of a first image converting tube section of the proximity-focus type and a second image converting tube section which produces an image reversal, said image converting tube sections having a photocathode on the front thereof responsive to both infrared and visible light radiation, said image converting tube sections having an image screen on the rear thereof for producing an intensified image, an optical input system including a front object lens and a ring for adjusting the focal point of the front object lens for forming an image on the photocathode on the front of the image converter, a collimating lens having a focal plane located in the image screen on the rear of the image converter, a central tube member housing said image converter and said collimating lens, a pair of viewing devices each including a pair of 90° prisms, an object lens interposed between each pair of prisms, and an eye piece receiving respective portions of the parallel rays from the collimating lens to form a binocular with said collimating lens, and said prisms arranged so that light paths through the viewing devices are reflected alongside the central tube member over the collimating lens to position the eye pieces closely behind the plane defined by the rear end of the central tube member.