Method of removing color centers from film coated fluoride optical elements

摘要

The present invention provides an optical element fabrication method, exposure apparatus, device fabrication method, and devices. The fabrication method can reduce an optical absorption produced when a thin film is fabricated on a substrate and can fabricate an optical element having excellent optical characteristics. The present invention is especially effective when the substrate includes fluoride crystal(s). An optical element fabrication method as one aspect of the present invention is characterized in comprising the steps of forming a thin film onto a substrate, and eliminating a color center produced in said forming step by irradiating light onto the substrate.