[F-2-2] Theoretical analysis of the diffraction characteristics of dual-period holographic gratings 〇Takeru Fugono1, Shuzo Masui1, Shotaro Kadoya1, Masaki Michihata1, Satoru Takahashi1 (1.The University of Tokyo) Keywords:Functional surface、Subwavelength structure、Interference lithography、Holographic grating、Hierarchical structure