Free-space digital optical systems have demonstrated the capability to provide thousands of optical connections between optoelectronic chips. This dense concentration of channels creates substantial challenges in monitoring individual connections for diagnostic purposes without compromising performance. Prom the concept of stroboscopic techniques, we have designed and constructed a multichannel optical diagnostic tool that operates analogously to an electronic-sampling oscilloscope. The tool is economically constructed by the use of commercially available video cameras and video-enhanced personal computers. An integrated software application operates the tool and displays multiple-channel waveforms. We demonstrate the oscilloscope-sampling optical waveforms of a two-dimensional optoelectronic modulator array operating at data rates from 0.5 to 4 Gbits/s.
