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.

The common-emitter amplifier circuit generates an output which transitions from a high state to a low state when light in the near-infrared range is detected by the phototransistor. The wavelength ...

A single phototransistor mimics retinal bipolar cell function while detecting visible and infrared light, enabling low-power image processing through programmable ON and OFF photoresponses. (Nanowerk ...

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 ...