The　path　of　photons　in　the　thin　film　(TF)　light　emitting　diode　(LED)　was　analyzed.　The　reflectivity　of　reflector　in　AlGaInP　TF　LED　with　and　without　the　AlGaInP　layer　was　contrasted.　The　absorption　of　the　AlGaInP　layer　was　analyzed　and　then　the　light　extraction　was　calculated　and　shown　in　figure.　The　TF　AlGaInP　LED　with　8　μm　and　0.6　μm　GaP　was　fabricated.　At　the　driving　current　of　20　mA,　the　light　output　power　of　the　latter　is　33%　higher.　For　the　0.6　μm　GaP　LED,　the　etching　of　heavily　doped　GaP　except　the　ohmic　contact　dot　area　is　advised.　The　design　and　optimizing　of　current　spreading　between　the　n-type　electrode　and　the　p-type　ohmic　contact　dot　need　further　research.