How do low-loss, high-bandwidth optical communication devices build a "super bridge" for high-speed information transmission?
Publish Time: 2025-11-17
In the era of rapid development of 5G, artificial intelligence, cloud computing, and the Internet of Things, global data traffic is growing exponentially. Traditional copper cable communication can no longer meet the demands for ultra-high-speed, high-capacity, and low-latency information transmission. Against this backdrop, optical communication technology, using optical fiber as the medium and optical communication devices as the core components, is becoming a "super bridge" for building modern information infrastructure. Low loss and high bandwidth are the two key characteristics that optical communication devices use to support this digital highway.1. Low Loss: Enabling Optical Signals to "Travel Further"When light transmits through optical fiber, energy attenuation, or "loss," inevitably occurs due to factors such as material absorption and scattering. If the loss is too high, the signal needs frequent relay amplification, increasing costs and introducing noise and delay. Modern optical communication devices, through material optimization and structural innovation, reduce transmission loss to extremely low levels.Single-mode optical fiber made of high-purity quartz glass achieves a loss as low as 0.2 dB/km in the 1550nm wavelength window, meaning that approximately 1% of the original power is retained after optical signals have traveled 100 kilometers. Combined with low-noise erbium-doped fiber amplifiers and Raman amplification technology, repeaterless transmission over thousands of kilometers can be achieved without photoelectric conversion. Furthermore, optical devices such as couplers, isolators, and wavelength division multiplexers utilize precision coating, micro-nano fabrication, and thermal stability design to control insertion loss to within 0.1 dB, minimizing energy leakage in the link. This extremely low-loss characteristic enables efficient, stable, and long-distance information transmission in transoceanic submarine cables, national backbone networks, and even data center interconnections, laying the physical foundation for global interconnectivity.2. High Bandwidth: Carrying Massive Data TorrentsIf low loss solves the problem of "transmitting over long distances," then high bandwidth answers the challenge of "transmitting large volumes." Optical communication boasts bandwidth potential far exceeding that of electrical communication—the theoretical bandwidth of a single optical fiber can reach over 50 THz, millions of times that of copper cables. Optical communication devices are the core engine for unlocking this potential.First, wavelength division multiplexing (WDM) technology multiplies transmission capacity by simultaneously transmitting multiple optical signals of different wavelengths within the same optical fiber. Dense WDM systems can accommodate over 160 channels in the C+L band, achieving a total single-fiber capacity exceeding 100 Tbps. This relies on key components such as high-precision arrayed waveguide gratings, tunable lasers, and narrow-linewidth filters.Second, high-speed modulation devices, such as electro-absorption modulated lasers and silicon photonic modulators, support single-channel rates of 400G, 800G, and even 1.6T, meeting the ultra-high-speed interconnect requirements of data centers. Furthermore, the development of integrated photonic chips integrates multiple functional devices onto millimeter-scale silicon-based platforms, achieving high-density, low-power, and low-cost high-bandwidth transmission.3. Device Collaboration: Building an End-to-End Optical Network EcosystemOptical communication is not a solo performance by a single device, but a complete ecosystem composed of light sources, modulators, optical fibers, amplifiers, filters, detectors, and more. Performance advancements in each type of device drive overall system upgrades.In 5G fronthaul networks, miniaturized, low-power 25G/50G optical modules ensure high-speed connections between base stations and the core network; within data centers, VCSEL-based multimode optical modules achieve short-distance, high-bandwidth interconnects at low cost; and in backbone networks, coherent optical communication devices, combined with digital signal processing, enable ultra-long-distance, ultra-high-capacity transmission. These devices not only pursue performance limits but also emphasize reliability, compatibility, and manufacturability, ensuring long-term stable operation of optical networks in complex environments.From intercity backbone networks to cloud services behind mobile phones, from remote surgery to metaverse interaction, optical communication devices, with their core advantages of low loss and high bandwidth, silently build "super bridges" to the digital world. Though unseen by the public, they are indispensable cornerstones for the efficient operation of modern society.
