Patented Integrated Circuit Measures Time-of-Flight to Trillionths of a Second

LIVERMORE, Calif., April 30 -- Sandia National Laboratories/California engineer Ken Condreva has built a better stopwatch. It's smaller than a dime, accurate to 125 picoseconds, and can be produced far more inexpensively than comparable devices.
    The inspiration for his invention was the need to accurately record critical timing signals in weapon test flights. New telemetry systems required a compact, lightweight and low-power device for this purpose.
    His invention became the FALCON, an integrated circuit that uses his patented "Pulse Stretcher" technique to increase resolution up to 200 times for a low-power electronic clock (using 300 mW at 40 Mhz). The circuitry provides greater resolution by lengthening duration of the output signal, making it last from 64 to 200 times longer than the input signal. Although the input pulse is "stretched" in real time, the technique can be compared to recording a sporting event with fast-action film and replaying it at slow speed to clearly see what happened.
    The integrated circuit uses standard commercially available CMOS technology and could be inexpensively manufactured by most semiconductor businesses, said Sandia National Labs/California business developer Scott Vaupen.