What is the term for a diode that emits light?

What is the term for a diode that emits light?

• A. LED
• B. Photodiode
• C. PN junction
• D. Transistor

Answer: (A)

Light-emitting diode, or LED, is a diode designed to emit light. When a forward-biased current crosses the PN junction, electrons and holes recombine in the active region and release energy as photons. The color of the emitted light comes from the semiconductor’s bandgap energy, which varies by material. A photodiode, by contrast, is built to detect light rather than produce it. A PN junction is the basic diode interface, not specifically for light emission. A transistor is used for amplification or switching, not primarily for light emission. So the term for a diode that emits light is the LED.

Light-emitting diode, or LED, is a diode designed to emit light. When a forward-biased current crosses the PN junction, electrons and holes recombine in the active region and release energy as photons. The color of the emitted light comes from the semiconductor’s bandgap energy, which varies by material. A photodiode, by contrast, is built to detect light rather than produce it. A PN junction is the basic diode interface, not specifically for light emission. A transistor is used for amplification or switching, not primarily for light emission. So the term for a diode that emits light is the LED.