As　one　of　the　most　rapidly　growing　areas　of　the　tunable　semiconductor　diodes,　tunable　vertical　cavity　surface-emitting　lasers　(VCSELs)　have　been　focused　on　and　the　wavelength　tuning　characteristics　have　been　investigated　in　detail.　By　applying　an　electrostatic　bias　between　the　semiconductor　and　the　cantilever　which　is　an　external　reflector　apart　from　the　device,　the　stimulated　wavelength　can　be　continuously　modulated　with　a　continuous　tuning　over　a　10nm　spectral　range.　It　is　found　that,　as　the　tunable　VCSEL　operate　in　its　stable　regime,　the　displacement　of　the　cantilever　will　result　in　a　periodic　variation　in　the　intensity　and　wavelength　with　a　period　of　half　the　resonant　wavelength.　We　also　found　the　same　phenomenon　in　the　tunable　RCLED.　In　addition,　based　on　our　observations,　precise　analysis　is　presented　from　the　Lang　and　Kobayashi　model.　Our　results　show　an　adequate　match　between　theory　and　experiments　for　the　detailed　tunable　spectra.　These　results　can　be　used　to　greatly　enhance　the　performance　of　tunable　VCSEL　and　RCLED.　©　2009　SPIE-OSA-IEEE.