An optical assembly allows video imagery to be imported into a night vision device and exported therefrom. The assembly can be an insert that is installed between the image tube and eyepiece of an existing night vision device to retrofit the device for superimposing images. Images imported—e.g., images captured by thermal detectors, maps, compass information, training video, etc.—are received wirelessly and injected into the optical train of the night vision device such that both the night vision scene from the goggle and the injected imagery can be simultaneously observed at the eyepiece. Combined images can be transmitted to external systems for observation purposes such as real-time active mission feedback. The insert provides sensor fusion and interconnection to the digital battlefield for presently-fielded night vision goggles. It receives power and optical information from the existing goggle. Goggles using this device can have full functionality and performance.