Do the speed display screens on highways take photos?
2 Answers
The speed display screens on highways do not have the function of capturing speeding violations. Speed reminder screens: They are designed to provide speed feedback to drivers. In fact, the complete system of a speed reminder screen consists of a speed measurement screen (the core speed measurement and display component) and a speed limit sign. Each sign features a prominent number indicating the speed limit for that lane. When a detected vehicle exceeds this speed limit, the speed displayed on the LED screen turns red to alert the driver. Principle: The speed reminder screen is composed of a radar and an LED screen, operating on the principle of radar speed measurement. When a vehicle enters the radar detection zone, the radar continuously emits electromagnetic waves towards the moving vehicle, which are then reflected back. The speed of the detected vehicle is calculated based on the frequency difference between the emitted and reflected waves.
I've been driving for almost 20 years, and I always see those big speed display screens on highways. To be honest, they're just reminders—they don't take photos or issue fines. They use radar to measure your speed and show it to you, making you aware if you're speeding. Their purpose is to improve road safety and reduce accidents. The real enforcement devices are fixed speed cameras or mobile police vehicles—those are the ones that capture license plates and issue fines. Don't worry about the screens taking photos; they're purely well-intentioned tools to remind people to slow down and drive carefully. I remember last year on a long trip, one screen showed I was 10 km/h over the limit, so I eased off the gas and ended up avoiding a traffic jam ahead.
