How does a Lidar measure the distance to a vehicle?

• A. By calculating speed based on the vehicle type
• B. By using radar technology
• C. By measuring the time it takes for the laser pulse to return
• D. By estimating based on vehicle size

Answer: (C)

A Lidar system measures the distance to a vehicle by emitting a laser pulse and then calculating how long it takes for that pulse to reflect off the vehicle and return to the Lidar unit. This process relies on the speed of light, allowing Lidar to determine distance very accurately based on the time delay of the received signal.

The principle behind this measurement is simple: the system knows how fast light travels, so by measuring the time it takes for the laser pulse to make the round trip to and from the vehicle, it can compute the distance to the object. This method allows for precise distance measurement, which is essential for applications in speed enforcement and traffic monitoring.

The other options do not accurately describe how Lidar functions. Estimating distance based on vehicle size or calculating speed based on vehicle type do not reflect the direct measurement capabilities of Lidar technology. Similarly, while radar technology is another form of speed measurement, it operates on different principles compared to Lidar, which specifically utilizes laser pulses.