We　develop　an　analytical　solution　based　on　the　cavity　coupling　that　can　be　used　to　predict　the　output　performance　of　the　1D　defect　modes.　This　solution　gives　a　concise　analytical　expression　of　every　emission　wavelength　of　the　defect　modes　with　arbitrary　defect　numbers.　The　splitting　and　the　resonance　modes　are　explained　qualitatively　by　the　proposed　theoretical　model.　The　output　performance　obtained　by　the　analytical　solution　are　in　good　consistency　with　that　obtained　by　the　numerical　simulations　using　the　finite-difference　time-domain　method.　These　results　may　provide　a　useful　alternative　to　customize　the　1D　coupled　defect　mode　laser.　©　2020　Optical　Society　of　America　under　the　terms　of　the　OSA　Open　Access　Publishing　Agreement