The application of speedometer in traffic law enforcement:

At present, the most commonly used speed measurement methods in my country include radar speed measurement, laser speed measurement, ground sensing coil speed measurement, video speed measurement and infrared detection. At present, the two most used are radar speed measurement and laser speed measurement.

1. The biggest difference-different principles

The principle of laser speed measurement is to calculate the time difference by using the emitted and received laser beams to determine the distance between the measured object and the test point. Laser speed measurement is to perform laser distance measurement on the measured object twice with a specific time interval, and obtain the moving distance of the measured object in this time period, thereby obtaining the moving speed of the measured object.

The principle of radar speed measurement is to apply the Doppler effect, that is, the moving object has the frequency shift effect on the received electromagnetic wave. The radar speed meter calculates the movement speed of the measured object based on the calculation of the frequency shift of the received reflected wave.

2. The speed range is different

The distance of laser speed measurement is farther than the effective distance of radar speed measurement. It can measure 1000M away, and it can be captured from a long distance.

The electromagnetic wave beam emitted by the radar has a certain opening angle, so the effective speed measurement distance is shorter than that of the laser speed measurement, and the farthest speed measurement distance is 800 m (for large vehicles).

3. Different measurement accuracy

The laser beam emitted by the laser speedometer is extremely thin (the divergence angle of the laser emission part is 3mrad), which can be accurately measured. The diameter is only 30 cm at 100 meters, so the irradiation area is small and it can accurately aim at any target.

The radar beam of the radar speedometer is larger than the irradiation area of the laser beam (ray), so the radar speed measurement is easy to capture the target, does not require precise aiming, and it is difficult to perform a single speed measurement of the vehicle. The fixed speed measurement error of the radar is ±1Km/h, and the measurement error during movement is ±2Km/h.

1. Advantages of laser speed measurement:

Advantages of laser speed measurement:

Sensitive speed measurement: the measurement response is fast, and the single speed measurement time is about 0.33-0.66 seconds.

Anti-interference: Because the laser beam of the laser speedometer is extremely thin and its response time is extremely fast, the general electronic detectors on the market are useless for the interference and detection of the laser speedometer.

The first-class safety laser is safe for human eyes: the laser speedometers used in most countries currently use a first-class safety laser, which is safe for human eyes.

Good forensic ability: The forensic ability of laser speedometer is far greater than that of radar speedometer, so it is widely recognized and promoted all over the world. For example, the Onick LSP320 handheld camera laser speedometer can measure speed while taking photos. The photos are stored in the instrument for easy evidence collection.

Low energy consumption and long use time: The power consumption of the laser rangefinder is relatively low, and it can be used continuously for a long time after a charge.

Disadvantages of laser speed measurement:

Stationary use: In view of the principle of laser speed measurement, the laser speedometer cannot be used in motion, and can only be used in a static state; therefore, the general traffic police put the instrument on the patrol car and use it when stopped.

Expensive: Laser speedometer is more expensive than radar speedometer, which is more suitable for customers with sufficient budget.

Advantages of radar speed measurement:

Dynamic use: The radar speed measurement equipment can be installed on the patrol car, and it is a very important part of the "mobile electronic police" to detect the speed of the vehicle during the movement.

Low price: Radar speedometer is cheaper than laser speedometer, and it is more suitable for customers with low budget.

Disadvantages of radar speed measurement:

Easy to be interfered: If there is an object with stronger reflective ability next to the target, the speed measuring radar can only detect the object with strong reflective ability. When there are two cars in parallel, the radar speedometer cannot distinguish which car is a speeding vehicle; when the measurement signais reflected many times, the result of the speed measurement radar will also be wrong; radio waves will interfere with the speed measurement radar, causing the measurement result is distorted.

Weak concealment: The radar sensor can detect the radar speedometer but it is extremely difficult to detect the existence of the laser speedometer.

At present, many law enforcement agencies in the country are already using handheld laser speedometers LTI TruSpeed, Onick LS320, LS320 laser speedometers with printing function, and LSP320 speedometers with photo forensics. Laser speedometer is a new type of traffic management law enforcement tool. It provides a reliable technology for obtaining evidence for illegal and speeding. It overcomes the slow speed of radar speedometer measurement, beam width and radiation's adverse effects on human health, etc. Disadvantages, so it has the incomparable advantages of radar speedometers. It can measure speed and range, and is highly functional. It can easily detect the speed of a single vehicle or even a motorcycle from a busy multi-lane highway. speed. With the widespread use of new equipment, radar detectors alone cannot provide adequate protection. It can be seen that laser speed measurement will be more and more widely used in traffic law enforcement in the future.