Exposure apparatus, exposure method, and fabricating method of display panel substrate

An exposure apparatus, an exposure method and a fabricating method of display panel substrate for precisely detecting a strength distribution of a light beam irradiating from a light irradiating device are provided. A detecting tool (50) which shields a portion of a light beam irradiating from a light irradiating device (20) moves in an irradiated region (26a) of the light beam irradiating from the light irradiating device (20); meanwhile, the light beam irradiating from the light irradiating device (20) with a portion thereof shielded by the detecting tool (50) is received, and an entire strength of the received light beam is detected. According to a change in the entire strength of the received light beam as a movement of the detecting tool, the strength of the light beam shielded by the detecting tool (50) and a position of the detecting tool (50) are detected in order to detect a strength distribution of the light beam. An unevenness of the strength distribution of the light beam is corrected according to