1. A method of operating an emission diode for junction temperature determination, comprising: characterizing the emission diode by measuring an operating temperature of the emission diode when producing emissions at a predetermined wavelength; setting a target operating temperature equal to the measured operating temperature; providing a drive current to the emission diode at a level sufficient to enable emissions by the emission diode; removing the drive current from the emission diode; providing a reference current to the emission diode at a level less than the drive current level after removing the drive current from the emission diode; determining a forward voltage level of the emission diode under application of the reference current; and controlling an operating temperature of the emission diode based on the forward voltage level and the target operating temperature.