An image display device and controlling method capable of optimizing a state of the image display device for a user at a desired position. The display device includes: an imaging section that takes an image of a predetermined range of a dynamic image with respect to an image display direction; an image analyzing section that analyzes the dynamic image taken by the imaging section and calculates a position of a user; a system optimization processing section that calculates system control information for optimizing a system based on the position of the user calculated by the image analyzing section; and a system controlling section that optimizes the system based on the system control information calculated by the system optimization processing section.