MITSUBISHI

MITSUBISHI LASER DIODESML4XX10 SERIESFOR OPTICAL COMMUNICATIONI Forward current vs. voltageTypical forward current vs. voltage characteristicsare shown in Fig. 4. In general, as the casetemperature rises, the forward voltage VF decreasesslightly against the constant current IF. VF variestypically at a rate of - 2.0mV /"C at IF = 1 rnA.Fig. 4 Forward current vs. voltage characteristics40:( 30,§.!!.E!! 20:;u"E~0 10u.oTc=50"C-Tc=25"C-o 1.0 2.0jForward voltage VF (V)I Optical output dependence of emission spectraTypical emission spectra under CW operation areshown in Fig.5. Generally, at the output of about3mW, the laster oscillates in the multi-mode; whenthe output is raised to about 5mW, it beginsoscillating in the single mode. The peak wavelengthdepends on the operating case temperature andforward current (output levle).Fig. 5 Emission spectra under CW operationWavelength A (nm)D'lTemperature dependence of peak wavelengthA typical temperature dependence of the peakwavelength at an output of CW 3mW is shown inFig.6.As the temperature rises, the peak wavelengthshifts to the long wavelength side at a rate ofabout O.25nm/"C typical.Fig. 6 Temperature dependence of peak wavelengthE50.'"'" 0,c:~~~""~78578478378278 1VPo .=3mW/V/" V/78025303540Case temperature Te ("C)'.' MITSUBISH. I ..... ELECTRIC 2-47