Testing apparatus and testing method

A testing apparatus comprising:

• a display means that displays, in a background, a visual target varying in size and color for testing a color-related visual function of a subject, the visual target and the background being displayed such that a luminance of the background has a substantially same numerical value in luminance of the visual target;
• a display control means that causes, in a state in which the subject is caused to gaze at a predefined point on the display means, the display means to display the visual target, while changing a size of the visual target, such that a threshold that is a size of the visual target that determines whether or not the subject can perceive the visual target is obtained in a peripheral region of a visual field center or at the visual field center;
• and
• a obtaining means for obtaining at least one of the threshold in the size of the visual target that determines whether or not the subject can perceive the visual target as displayed in one of a predetermined set of colors over the background whose luminance value is substantially the same as the luminance of the visual target.