Night vision goggle with improved optical system

Claim 1

A night vision goggle, comprising: a housing; a collimator assembly, supported within the housing, having an optical axis; a pair of afocal telescopes, supported within the housing, each of the telescopes having an aspheric singlet objective lens, an aspheric singlet eyepiece lens, and a mirror mounted between the objective lens and the eyepiece lens, each of the telescopes also having an entrance pupil, an exit pupil, and an optical axis offset from the optical axis of the collimator, for transmitting images separately to each eye of a viewer; a splitter member, mounted within the housing concentrically with the optical axis of the collimator assembly and located optically between the collimator assembly and each telescope, for reflecting an image viewed by the collimator to each of the telescopes; an objective lens assembly, supported within the housing, for transmitting an image incident thereon to the collimator assembly; an image intensifier tube, located between the objective lens assembly and the collimator assembly, for intensifying an image viewed by the objective lens assembly before its transmittal to the collimator assembly; and a pair of achromatic doublet lens assemblies, each doublet lens assembly mounted within the housing near the entrance pupil of a telescope and with its optical axis coaxial with the axis of the telescope, each doublet lens assembly being a cemented doublet with approximately zero optical power, for collecting light from a sub-diameter, decentered aperture of the collimator, and for correcting the axial chromatic aberration of the afocal telescope with which it is optically associated.