Exposure device and exposure method

A film manufacturing method, comprising:

• forming a roll die used in roll imprint;
• and
• transferring a pattern on the roll die to a film substrate,
• wherein the forming the roll die comprises:
• rotating an exposure object and generating a rotational synchronization signal;
• causing a laser light to scan along an exposure surface of the rotating exposure object in a direction crossing a direction of rotation of the exposure object, the exposure surface is irradiated with the laser light;
• and
• modulating an intensity of the laser light in accordance with the rotational synchronization signal,
• wherein the intensity of the laser light is modulated in accordance with a rotation period of the exposure object,
• wherein the intensity of the laser light with which the exposure object is irradiated in a same rotation phase of the exposure object is changed with time, and
• wherein a minimum value of the intensity of the laser light is lower than a threshold value of an amount of the laser light received for causing a reaction that makes the exposure object soluble in a developer;
• and
• forming grooves separated from each other on the exposure object.