We　propose　a　simpli.ed　model　to　analyse　the　temporary　behaviour　of　transmittance　for　holographic　photopolymers,　based　on　the　existing.　rst-　harmonic　di.　usion　theory,　with　assumptions　of　constant　polymerization　coe.　cient　and　negligible　di.　usion　e.　ect　for　noise　gratings.　By　applying　this　model　to　measure　real-　time　transmittance　of　our　novel　blue-　sensitized　photopolymer,　the　bleaching　time　constant　of　dye　and　polymerization　rate　are　extracted,　and　the　e.　ect　of　the　material　composite　on　the　noise　property　is　revealed.　This　provides　a　prompt　method　to　assess　the　performances　of　holographic　photopolymers.