Patent ID: 7538768

Claim:
An image display device for displaying images by either of a two-dimensional image or a three-dimensional image comprising: right and left image display elements which receive respective right and left image signals, which when viewed concurrently, provide a stereoscopic image to a user; three-dimensional protecting process means which detects a parallax value for each of the right and left image signals supplied to the right and left image display elements, and an evaluation value as a degree of influence given to the viewer is determined for each of the signals, by calculating a parallax statistic which is statistical data of the parallax value included in the stereoscopic image based upon the detected parallax value, performing both static evaluation and dynamic evaluation of the parallax value based on the parallax statistics to determine the respective evaluation values, and then integrating both of the evaluation values, the determined evaluation value for each of the signals is an accumulated value, the accumulated value being calculated by sequentially adding the evaluation value, and a determination is made as to whether the accumulated value is at least equal to a predetermined threshold value; a display control means that selectively displays whether the accumulated value is at least equal to the predetermined threshold value on the right and left image display elements; a password input means for selectively inputting a password of a viewer; a password storage means for storing the password provided by the password input means; and a password decision means for deciding whether the password from the password input means is stored in the password storage means, and when it is determined that the password is stored, even if it is determined that the evaluation value is at least equal to the predetermined threshold value, without displaying the decision on the right and left image display elements, the display control means displays the three-dimensional image on the right and left image display elements, and when it is determined that the password is not stored even if it is determined that the evaluation value is at least equal to the predetermined threshold value, the display control means displays the two-dimensional image on the right and left image display elements, wherein when the evaluation value is at least equal to the predetermined threshold value, the display control means selectively displays whether or not the image together with the displaying are continuously observed, on the right and left image display elements.