The　light　power-current　(L-I)　characteristics　of　vertical　cavity　surface　emitting　lasers　(VCSEL),　which　have　the　same　fabrication　process　and　structure,　but　different　detunings　of　Fabry-Perot　(FT)　resonance　from　the　gain　peaks　at　room　temperature,　were　measured　in　the　temperature　range　from　261K　to　369K.　The　relationships　between　the　output　light　power,　threshold　current,　slope　efficiency　and　lasing　wavelength　and　the　temperature　were　studied　using　the　obtained　characteristics　in　combination　with　the　test　results　of　their　reflectivity　spectra　and　photoluminescence　signals,　as　well　as　the　simulated　results　of　their　reflectivity　spectra　and　gain　spectra　at　different　temperatures.　The　temperature　characteristics　of　the　new　material　AlInGaAs　were　found.　The　effect　which　the　differences　between　the　gain　spectrum　and　the　FP　resonance　had　on　the　output　characteristics,　especially　on　the　threshold　current　had　been　obtained.　We　found　that　VCSEL　devices　with　minimal　threshold　currents　and　small　threshold　current　change　with　temperature　at　room　temperature　could　be　obtained　by　adjusting　the　detuning　of　Fabry-Perot　(FP)　resonance　from　the　gain　peak.　Using　this　method,　AlInGaAs/AlGaAs　strained　quantum　well　VCSEL　devices　which　have　the　characteristic　temperature　of　333K,　and　minimal　threshold　current　and　small　threshold　current　change　with　temperature　in　the　321K　to　345K　range　were　fabricated.