Which speed measurement instrument uses a laser to determine speed?

The instrument that uses a laser to determine speed is Lidar. This technology operates by emitting a series of laser pulses that bounce off a moving vehicle. By measuring the time it takes for the laser to return to the device, Lidar can calculate the distance to the vehicle and, with repeated measurements, determine its speed with great accuracy.

Lidar is particularly valued for its precision, and it can work effectively in various conditions, including poor visibility. It is less prone to interference from weather conditions compared to other technologies, making it a reliable tool for measuring vehicle speeds.

In contrast, Radar uses radio waves, a speedometer measures speed based on vehicle motion and its wheels, and GPS devices calculate speed based on satellite positioning and travel distance over time. Each of these technologies has its own strengths and applications, but in this scenario, Lidar is specifically designed to utilize laser technology for speed measurement.