How does a police laser gun measure speed?
Thursday, April 29th, 2010 at
9:00 am
How does the device to measure speed / nd how scientific principles and concepts have been used in tecgbological developments
Tagged with: Laser • Laser Gun • Laser Measure • measure • Measure Speed • police • Police Laser • speed
You send a radio signal, will receive the same signal bounces back as the objects. However, the radar frequency is different when it comes back, and from this difference of the radar gun object speed can be calculated.
A laser speed gun measures the round-trip time for light to reach a car and reflect back. The light from a laser speed gun moves a lot faster than sound – about 984 million meters per second (sec 300 000 000 m /), or about 1 foot (30 cm) per Nanosekunde.Ein laser speed shoots a short burst of infrared laser light and then waits for it to reflect off the vehicle. The weapon counts the number of nanoseconds it takes for the return trip, and by dividing by 2 is the distance to the vehicle to calculate. If the gun takes 1,000 samples per second, it can compare to the change of distance between samples and calculate the speed of the car. By taking several hundred samples over the course of the second third or so, the accuracy is very high be können.Die size of the “cone” is sending light that the gun is very small, even with a number such as 1,000 feet (300 meters ). The cone at this distance was 3 feet (1 meter) in diameter Close proximity allows the gun to target a specific vehicle. A laser speed gun is also very genau.Das only thing here is the laser gun needs a car to be aligned – normal police radar with a broad radar beam can Doppler shift without erkennen.Hinweis to the first answer: Asker asked LIDAR or laser-gun , not radar.