An exposure apparatus includes a light source, an illuminating member, a projecting member, a stage, an inspecting member, and an information processing member. The light source is configured to provide a light in accordance with a pulse event generation (PEG) representing a period of light radiation. The illuminating member is configured to change the light into point lights. The projecting member is configured to project the point lights according to a photoresist shape extending in various directions. The point lights are projected on the stage. The inspecting member is configured to inspect a photoresist pattern formed by the projected point lights. The information processing member is configured to analyze different photoresist patterns corresponding to different PEGs to select one PEG from the different PEGs. The one PEG being associated with a minimum error in the various directions.