Illumination apparatus, optical apparatus, imprint apparatus, projection apparatus, and method of manufacturing article

A method of manufacturing an article, the method comprising steps of:

• forming a pattern on a substrate using an imprint apparatus;
• and
• processing the substrate, on which the pattern has been formed, to manufacture the article,
• wherein the imprint apparatus molds an imprint material on the substrate to form a pattern on the substrate, and includes:
• a heating device configured to heat the substrate by illuminating the substrate to deform the substrate,
• wherein the heating device includes an illumination apparatus and is configured to heat the substrate by illuminating the substrate via the illumination apparatus,
• wherein the illumination apparatus performs oblique illumination and includes:
• a first optical element formed with an array of a plurality of optical components each configured to generate a point light source;
• and
• a second optical element configured to receive light from the first optical element and form an illumination region, with a power thereof in one direction being different from a power thereof in a direction perpendicular to the one direction,
• wherein each of the first optical element and the second optical element has a rotation angle about an optical axis thereof so as to perform compensation for distortion of the illumination region by the oblique illumination, and
• wherein the rotation angle of the first optical element is different from the rotation angle of the second optical element.