On the 2021 CCTV Spring Festival Gala stage, a new media backdrop comprised of 154 LED screens flashed synchronously, presenting live, live comments from "cloud audiences" thousands of miles away. As the singers interacted with the rolling stream of blessings, this bridge woven by code and optoelectronics completely redefined the boundaries of interactive performance.

The core technology driving this interaction is a real-time channel built on the WebSocket full-duplex communication protocol. It flows like a never-ending stream of data: user comments are validated by the front-end and then streamed to the server. The back-end system filters sensitive words and normalizes the word count in milliseconds before distributing the data to various display nodes via a distributed architecture. To ensure that the massive volume of comments does not clutter the screen, the system employs a timeline sorting algorithm combined with dynamic transparency adjustment technology, allowing the text to flow across the screen like comments without obscuring the main performance.

LED screens are the ideal medium for carrying real-time comments due to their revolutionary stage presence. Compared to traditional static screens, they not only enable instantaneous image switching, but also deliver high brightness and contrast, rendering text vibrant and eye-catching. The modular design allows the screens to be freely assembled into creative shapes, such as arcs and Rubik's cubes, seamlessly integrating with stage lighting and music. Just as at Jay Chou's concerts, the bullet screens presented by Lianchengfa's Longteng S series transparent screens seemed to float in mid-air, synchronizing with the rhythmic colors of glow sticks, elevating the audience to a climax.268

Data confirms its appeal: after a livestreaming platform introduced a real-time bullet screen wall, user viewing time surged by 20% and the volume of bullet screens soared by 50%. During the 2019 Spring Festival, a game livestream even reached a peak of 10,000 bullet screens per minute.5 This interactive model has extended beyond performances to education: after implementing the bullet screen feature, student engagement in an online class soared by 40%.5

Future interactive formats are emerging. The Migu Hui Festival experimented with linking cheering sticks to the color of the bullet screen wall through sensors, allowing audience members to trigger special effects by waving their devices.9 The integration of AI-generated content (AIGC) technology may enable bullet screens to be automatically transformed into 3D virtual avatars that appear on screen.8 As technology evolves from "one-way display" to "two-way perception," every barrage of light across the LED screen becomes the heartbeat of the audience's resonance with the stage.

From cold pixels to a throbbing emotional connection, LED displays, with their photoelectric power, have redefined the very essence of interactive performances.

No longer a passive canvas, they have become a generator of collective memory, written by millions of people.