1. An apparatus comprising: a laser diode to emit light in response to a drive current; an adaptive model to estimate a quantum well temperature of the laser diode in response to prior values of the drive current, the adaptive model to provide an estimated quantum well temperature; a mapping component to map the estimated quantum well temperature and a desired radiance value to the drive current; and a second mapping component operable to map drive current to quantum well heating, and to provide an estimate of the quantum well heating to the adaptive model.