Solve this multiple-choice question and choose the correct option.

Semiconductor optoelectronics: What do LEDs in electronic toys emit? State the type of electromagnetic radiation typically produced by Light Emitting Diodes. Choose the correct option.

Difficulty: Easy

Broadband white light only
Microwaves
Nearly monochromatic visible or infrared light
X-rays

Correct Answer: Nearly monochromatic visible or infrared light

Explanation:

ConceptAn LED is a p–n junction that emits photons of energy ~ bandgap E_g, producing narrow-band (quasi-monochromatic) visible or IR light depending on semiconductor material.

Final AnswerNearly monochromatic visible or infrared light

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