PURPOSE: An image display method and a device thereof are provided to use a projected screen as a touch screen in order to implement writing function on the screen or specific location emphasis function, thereby encouraging the interaction between auditors and speaker. CONSTITUTION: An image display device detects a projected screen area from an acquired image(402). The image display device detects an optical point area(403). The image display device calculates an optical point area location by comparing the projected screen area with the optical point area(404). The image display device determines a display mode and a command mode. The image display device displays a color which is previously set on the calculated location in the display mode(406). The image display device executes a command on the calculated location in the command mode(407).
