The present invention relates to a video output device mounted on a vehicle to implement augmented reality, and a method for controlling the same. The video output device comprises: a video output unit for outputting visual information for implementing the augmented reality; a communication unit for receiving a front video captured of the front of the vehicle; and a processor for investigating, in the front video, at least one to-be-driven lane on which the vehicle is to be driven, and controlling the video output unit such that main carpet images guiding the to-be-driven lanes are output lane by lane.