A thyristor will stay conducting until the current through the device is zero (“current zero”) or perhaps slightly negative.  LLNL’s approach is to use the opticondistor (“OTV”) to force this current zero in order to force the device into an “off” state.  By combining a light-activated thyristor with an OTV, a noise-immune, high efficiency, high-power switching device can be…

LLNL researchers have developed a technology suite that includes several methods for detecting trace levels of illicit drugs even in mixtures. These methods can be used as a rapid screening test for incoming samples; for the samples that were determined to contain detectable amounts, they would undergo final verification using conventional laboratory analytical techniques.