US Patent 9638920 Torsional support for binocular display

A binocular head mounted display includes a first binocular eye piece including a first torsional brace and a second binocular eye piece including a second torsional brace configured to engage the first torsional brace. The binocular head mounted also includes a frame assembly holding the first binocular eye piece and the second binocular eye piece at an adjustable interpupillary distance. The frame assembly includes a torsional support to directly or indirectly engage the first torsional brace and the second torsional brace. Such engagement resists rotational movement of the first binocular eye piece relative to the second binocular eye piece.