method for testing flat panel display

The present invention is a flat panel display (FPD) relates to a test method, each from an image of a step for applying a video signal to the flat panel display, and acquiring an image of said flat panel display by a recording device, the obtained flat-panel displays where the original brightness information steps of calculating the phase and the original brightness information and the brightness difference between the junction brightness information for obtaining the position by joining the brightness information in accordance with the curved joint (curve fitting) on ​​the basis of the original brightness information by location to calculate a and a group is characterized in that it comprises a step of detecting a stain position having a brightness difference of more than the predetermined allowable range original brightness information, the brightness information junction. This makes it possible to quickly and accurately inspect the area of ​​the flat panel display type stains. Area stain