Light Output Versus Current and Ith
The light output is measured using a script in INTERCONNECT that increases the amplitude of the DC source, or the input current of the laser. The script then generates a graph for current against light output measured by the optical power meter(OPWM_2). The graph on the left in Fig. 6. shows this overall light output versus current graph up to 300mA, while the right shows a enlarged scale to find the point where the slope of the curve changes. By exporting the data and measuring slopes on Matlab, it was found that the point at which the slope changes is at 15.5mA, as seen by the red line . Hence the threshold current of this ECL is 15.5mA.