Now,　various　display　screens　transmit　massive　information　to　people　all　the　time　and　become　an　important　window　of　human-computer　interaction.　Solid　state　optical　coating　utilizes　optical　interference　effect　and　inherent　optical　properties　of　materials　to　achieve　multiple　colors.　In　this　paper,　between　Fabry-Perot　(F-P)　cavity　coating　with　dielectric　layer　and　strong　interference　effect　(SIE)　coating　without　dielectric　layer　were　compared.　Effect　of　film　thickness　on　F-P　cavity　optical　phase　change　coating　was　studied.　The　results　show　that　the　F-P　cavity　coating　with　a　dielectric　layer　has　more　reflective　states　than　the　coating　without　a　strong　interference　effect,　that　is,　potential　for　optical　coating　display.　In　addition,　in　the　F-P　cavity　coating,　by　controlling　the　thickness　of　SiO2　and　Ge2Sb2Te5　(GST)　film,　the　optical　coating　shows　rich　color　due　to　the　change　of　F-P　optical　cavity　length　and　strong　interference　effect　of　materials.　We　also　carried　out　a　study　of　the　flexible　substrate　compatibility　and　substrate　color　of　the　two　structures,　and　found　that　they　are　well　compatible　with　flexible　materials,　and　F-P　is　more　sensitive　to　substrate　color　than　SIE　structures　in　terms　of　substrate　color.　Due　to　the　far　subwavelength　layer　thickness,　most　phase　shift　is　accumulated　on　reflection　at　the　interfaces,　which　makes　the　reflectance　profile　robust　under　tilted　incidence.　©　Published　under　licence　by　IOP　Publishing　Ltd.