What does “mode locking” achieve in laser technology?

Mode locking is a technique used in laser technology to produce ultra-short pulses of laser light. This method works by locking different longitudinal modes of the laser's cavity together in such a way that they oscillate in phase, allowing the laser to emit light in a highly synchronized manner. When these modes are combined, the result is a train of light pulses, each lasting only a few picoseconds or even femtoseconds, depending on the specific laser setup and application.

These ultra-short pulses are crucial for a variety of applications, such as in telecommunications (for high-speed data transfer), medical procedures (like laser surgery), and scientific research (where precision timing is essential). The ability to generate these pulses at high repetition rates can lead to significant advancements in technology and research capabilities.

The other options do not accurately describe the primary achievement of mode locking. Continuous laser output is a different operational state of a laser, while increasing power levels involves amplifying the light rather than pulse formation. Enhancing the color spectrum pertains to modifying the wavelength output, which is also unrelated to the concept of mode locking. Thus, the correct answer highlights the specific outcome of the mode locking process within the context of laser technology.