Patent ID: 8729696

Claim:
A testing device for a laser diode (LD), comprising: a chuck for holding an LD die; a current source for supplying electric current increasing with a fixed increment to the LD die to drive the LD die to emit light, the current source comprising a voltage meter, the electric current having a sequence of current values, the voltage meter being configured for metering a sequence of voltage values across the LD die, the sequence of voltage values corresponding to the sequence of current values, respectively; a support positioned on the chuck and comprising a first cantilever extending above the chuck; and an optical power meter comprising a photo detector and a power meter; the photo detector being positioned on the first cantilever, facing the chuck, and configured for detecting power of the light emitted from the LD die, the power meter being electrically connected to the photo detector and configured for measuring a sequence of power values corresponding to the sequence of current values, respectively, an electro-optical property of the LD die being determined according to the sequence of current values, the sequence of voltage values, and the sequence of power values; wherein the support comprises a rotary plate, the first cantilever extends from the rotary plate, and the photo detector is capable of being positioned to directly face the LD die by rotating the rotary plate.