Before revision: 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.Real-world schematic diagrams omit the barrier symbol, and use a single set of directional arrows.
After revision: Schematic diagram of an opto-isolator showing source of light (LED) on the left, dielectric barrier in the center, and sensor (phototransistor) on the rightReal-world schematic diagrams omit the barrier symbol, and use a single set of directional arrows.