The present invention suggests a quantification method for changing visual fatigue generated in a 3D content which is a problem of safety in a 3D industry into the variation of face temperature. A visual fatigue measuring method by this method includes a step of measuring the thermal image of a face from a testee exposed to a visual stimulus, a step of analyzing the thermal image and detecting the change of heat according to the section of the face of a user, and a step of determining the visual fatigue from the size of the change of heat according to the section of the face.
Method for measuring Cognitive fatigue and apparatus adopting the method