An exposure apparatus includes a chamber surrounding a predetermined space, a first gas supply unit for supplying a first gas into the chamber, a second gas supply unit for supplying a second gas, different from the first gas into the chamber, and a switching mechanism for supplying one of the first and second gases by switching between the first and second gas supply units. The compounds are inhibitors of PI3K and are thus useful for treating proliferative, inflammatory, or cardiovascular disorders. The chiral fiber element is subjected to a broadband emission while monitoring its refection or the transmission spectrum.