Opto-isolator
An opto-isolator is an electronic component that can be used for galvanic isolation. It uses light for separating two circuits from each other.
Opto-isolator Media
Schematic diagram of an opto-isolator showing source of light (LED) on the left, dielectric barrier in the center, and sensor (phototransistor) on the right.
Planar (top) and silicone dome (bottom) layouts - cross-section through a standard dual in-line package. Relative sizes of LED (red) and sensor (green) are exaggerated.
Optocoupler on a circuit board. Note the pair of class Y1 safety capacitors
Obsolete photoresistor opto-couples (Russian OEP series pictured) retain a niche in modern guitar amplifier market.
A fast photodiode opto-isolator with an output-side amplifier circuit.
A reflective pair (left) and two slotted couplers with the light paths in purple
