Patent ID: 8120845

Claim:
An optical system comprising: an optical assembly frame having an input portion and an output portion; an objective lens assembly disposed at the input portion of the optical assembly frame, the objective lens assembly having an objective lens central optical axis; an eyepiece lens assembly disposed at the output portion of the optical assembly frame, the eyepiece lens assembly having 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 image intensifier disposed between the objective lens assembly and the eyepiece lens assembly, the image intensifier having 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 being offset from both the objective lens central optical axis and the eyepiece lens central optical axis by about half the distance; and an image intensifier collet disposed around a circumference of the image intensifier and coupled to the optical assembly frame.