Abstract: An interpupillary distance adjustment mechanism can be used to set the interpupillary distance (IPD) between a pair of independently pivoting monocular assemblies of a binocular optical device. Once the IPD of the binocular optical device has been set to match the IPD of a user, the interpupillary distance adjustment mechanism acts as a rotational stop enabling the user to return a monocular assembly of the binocular optical device to the desired position when the monocular assembly is moved from the stowed position to the operation position. An example interpupillary distance adjustment mechanism comprises: a housing adapted for attachment to a binocular optical device, a pair of set-stop pins, and a pair of thumb dials. The housing includes a pair of set-stop pin sheaths, one for each set-stop pin. Each thumb dial is operably connected to a set-stop pin and configured to longitudinally displace the operably connected set-stop pin from its sheath.

Abstract: A dual tube night vision device comprises a pair of independently pivoting night-vision monoculars connected to a bridge member. Each night-vision monocular is attached to the bridge member by a rotating arm and comprises a pod containing an image intensifier tube. Each arm allows the attached night-vision monocular to move through a rotational travel path, between a stowed position and a deployed position. The dual tube night vision device is configured to detect when the night-vision monoculars are, individually or collectively, moved to a stowed position and then temporarily cut off power to the stowed monocular(s) to increase battery runtime. Power is automatically restored, individually or simultaneously, to the night-vision monoculars when they are rotated back to the deployed positions. The dual tube night vision device uses one or more accelerometers to detect when the night-vision monoculars, individually or collectively, are in the stowed position or the deployed position.