The　definition　of　best　average　netted　dot　density(BANDD)is　proposed　based　on　the　research　of　the　pattern　of　the　netted　dot　for　light　guide　plate(LGP),　in　order　to　elaborate　the　optimal　design　for　the　netted　dot　of　LGP.　A　backlight　module(BLM)　is　modeled　in　the　light　simulation　software　based　on　the　theory　of　LGP　guiding　light,　a　group　of　differently　uniform　netted　dot　density　(NDD)　are　applied　in　the　model　to　test　the　effect　on　performance,　the　results　indicate　that　the　NDD　from　0.1　to　0.4　relatively　balances　efficiency　and　uniformity.　Further　more　the　layout　of　the　netted　dot　in　the　scale　mentioned　above　is　optimized　to　improve　the　uniformity;　the　results　of　simulation　state　clearly　with　the　NDD　from　0.2　to　0.35　can　reach　the　requirement　of　uniformity　in　development　stage.　The　corresponding　experimental　samples　are　made;　the　result　of　the　experiment　demonstrations　that　the　BANDD　is　located　in　0.25,　it　agrees　well　with　the　theoretical　predictions.　It　has　certain　guiding　significance　that　the　conclusion　of　the　study　are　applied　in　the　actual　development,　and　will　accelerate　the　procedure　of　BLM　and　reduce　the　counts　of　designing　editions,　and　cost　down　the　development　expense　of　the　BLM.　©,　2015,　Chinese　Optical　Society.　All　right　reserved.