Equivalent-Time Electro-Optic Sampling by use of a Picosecond Laser with a Voltage-Controlled Optoelectronic Pulse-Delay Tuning Circuit

Appl Opt. 2001 Oct 20;40(30):5530-8. doi: 10.1364/ao.40.005530.


We demonstrate a delay-line-free electro-optic sampling (EOS) system by using a novel ultrafast laser with a voltage-controlled pulse-delay tuning circuit (PDTC). The digital PDTC was designed as a substitute for a conventional optomechanical delay line in the EOS system, which facilitates the theoretical phase-tuning range of 4pi. The maximum delay time, tuning gain, and resolution of the PDTC are 3.6 ns (1.8 periods), 0.54 ns/V, and 0.2 ps, respectively. Arbitrary waveforms generated from microwave synthesizers, electrical pulse generators, and frequency prescalars are successfully sampled by use of this system, with a less than 8% deviation in the results.