Which type of optical amplifier is known to produce no measurable distortion to the modulated light wave?

The choice of the Erbium-Doped Fiber Amplifier (EDFA) as the correct answer is due to its unique properties in fiber optic communications. EDFA is widely recognized for its ability to amplify light signals in the 1550 nm wavelength region with exceptional fidelity. One of the key advantages of an EDFA is that it operates in a manner that introduces minimal distortion to the modulated light wave. This is primarily because EDFAs provide gain through a stimulated emission process that preserves the phase and amplitude characteristics of the incoming optical signal.

In practical applications, this quality is indispensable as it allows for extended transmission distances without compromising the integrity of the signal. The use of EDFAs is common in long-haul fiber optic networks where maintaining signal quality is critical. Their ability to amplify multiple channels simultaneously without introducing inter-channel distortion further exemplifies their effectiveness as an amplifier in optical communication systems.

Understanding this characteristic of the EDFA is essential for professionals working in fiber optics, as it directly influences network design choices when aiming for high-quality data transmission over long distances.