Abstract: An optical system includes an optical bench defining a mounting surface, an objective lens mounted to the optical bench, and an image intensifier tube. The image intensifier tube includes: (i) a housing defining an interior region and a mounting surface, and (ii) a photocathode bonded to a glass faceplate defining a faceplate surface, wherein the photocathode is positioned within the interior region of the housing, and wherein the mounting surface of the housing resides on the same plane as the faceplate surface. The mounting surface of the optical bench is mounted onto the mounting surface of the image intensifier tube housing such that the mounting surface of the optical bench resides on the same plane as the faceplate surface and the faceplate surface of the faceplate is the surface of the faceplate that is positioned closest to the objective lens.

Abstract: An optical system includes an optical bench defining a mounting surface, an objective lens mounted to the optical bench, and an image intensifier tube. The image intensifier tube includes: (i) a housing defining an interior region and a mounting surface, and (ii) a photocathode bonded to a glass faceplate defining a faceplate surface, wherein the photocathode is positioned within the interior region of the housing, and wherein the mounting surface of the housing resides on the same plane as the faceplate surface. The mounting surface of the optical bench is mounted onto the mounting surface of the image intensifier tube housing such that the mounting surface of the optical bench resides on the same plane as the faceplate surface and the faceplate surface of the faceplate is the surface of the faceplate that is positioned closest to the objective lens.

Abstract: An optical system includes an optical assembly frame having an input portion, an output portion, and an objective lens assembly disposed at the input portion of the optical assembly frame. The objective lens assembly has an objective lens central optical axis. An eyepiece lens assembly is disposed at the output portion of the frame. The eyepiece lens assembly has an eyepiece lens central optical axis parallel to the objective lens central optical axis and offset from the objective lens central optical axis by a distance. An inverting image intensifier is disposed between the objective lens assembly and the eyepiece lens assembly. The image intensifier has an image intensifier optical axis parallel to the objective lens central optical axis and parallel to the eyepiece lens central optical axis. The image intensifier optical axis is offset from both the objective lens central optical axis and the eyepiece lens central optical axis by about half the distance.

Abstract: An objective lens assembly for night vision goggles including an objective lens cell having a threaded portion, an optical bench having a mating threaded portion for receiving the objective lens cell, and a snap-ring washer for reducing backlash between the objective lens cell and the optical bench. The objective lens cell includes a first wall radially extending away from an axial neck portion, the optical bench includes a second wall radially extending toward the axial neck portion and oriented substantially parallel to the first wall, and the snap-ring washer circumferentially surrounds the axial neck portion of the objective lens cell. The biasing element is configured for a relaxed mode of operation and a compressed mode of operation. In the relaxed mode, the snap-ring washer is inactive, and in the compressed mode, the snap-ring washer reduces backlash between the lens cell and the optical bench.

Abstract: A helmet mount for night vision apparatus wherein night vision goggles can be coupled and uncoupled to its power pack without the use of tools and wherein the power pack can be coupled and uncoupled to a helmet without the use of tools. When an aviator wearing a helmet with night vision apparatus so mounted, is ejected from his aircraft both the goggles and the power pack are released from the helmet.

Abstract: An optical system includes an optical assembly frame having an input portion, an output portion, and an objective lens assembly disposed at the input portion of the optical assembly frame. The objective lens assembly has an objective lens central optical axis. An eyepiece lens assembly is disposed at the output portion of the frame. The eyepiece lens assembly has an eyepiece lens central optical axis parallel to the objective lens central optical axis and offset from the objective lens central optical axis by a distance. An inverting image intensifier is disposed between the objective lens assembly and the eyepiece lens assembly. The image intensifier has an image intensifier optical axis parallel to the objective lens central optical axis and parallel to the eyepiece lens central optical axis. The image intensifier optical axis is offset from both the objective lens central optical axis and the eyepiece lens central optical axis by about half the distance.

Abstract: An objective lens assembly for night vision goggles including an objective lens cell having a threaded portion, an optical bench having a mating threaded portion for receiving the objective lens cell, and a snap-ring washer for reducing backlash between the objective lens cell and the optical bench. The objective lens cell includes a first wall radially extending away from an axial neck portion, the optical bench includes a second wall radially extending toward the axial neck portion and oriented substantially parallel to the first wall, and the snap-ring washer circumferentially surrounds the axial neck portion of the objective lens cell. The biasing element is configured for a relaxed mode of operation and a compressed mode of operation. In the relaxed mode, the snap-ring washer is inactive, and in the compressed mode, the snap-ring washer reduces backlash between the lens cell and the optical bench.

Abstract: A helmet mount for night vision apparatus wherein night vision goggles can be coupled and uncoupled to its power pack without the use of tools and wherein the power pack can be coupled and uncoupled to a helmet without the use of tools. When an aviator wearing a helmet with night vision apparatus so mounted, is ejected from his aircraft both the goggles and the power pack are released from the helmet.

Abstract: A helmet mount for night vision apparatus including a night vision goggle rotatable between operative and inoperative positions. Retractable stop means are included on the mount for obstructing the rotation of the goggle from its inoperative to operative position without obstructing the rotation of the goggle from its operative to its inoperative position.