A designer who uses a phototransistor to convert a modulated optical signal to an electrical signal frequently encounters problems when high-intensity background light saturates the phototransistor.

Figure 1a shows a slotted optical switch. An LED is mounted in a plastic housing, facing a phototransistor, but separated by a gap. If something moves into the gap, it blocks the light path between ...

Researchers demonstrated a way to manipulate electrons in graphene using pulses of light that last less than one thousands trillionth (one quadrillionth) of a second. By leveraging a quantum effect ...

While many research efforts are underway to develop active devices that can function in the challenging terahertz spectrum, others are leapfrogging to try to get some devices operate into the ...