News center

Measurement Technology, Precise Measurement


25

2023

-

09

A laser rangefinder usually consists of a laser, a receiver, a timer and a displa


A laser rangefinder is an instrument that uses a laser beam to measure distances. Its principle of operation is based on the relationship between the speed of the laser beam and the reflection time of the beam.

A laser rangefinder usually consists of a laser, a receiver, a timer and a display. First, the laser emits a laser beam that is highly focused and monochromatic. This laser beam is focussed to a very small point and then further focussed by a lens or lenses to ensure that the laser beam is directed as accurately as possible to the target.

When the laser beam hits the target, a portion of the laser beam is reflected back by the target and captured by the receiver. A photosensitive device (e.g., a photodiode) in the receiver is capable of converting the optical signal into an electrical signal. The receiver also includes a narrowband filter to filter out stray light from the non-laser beam.

Next, this electrical signal is fed into a timer for processing. The timer starts timing and records the time interval between the emission and reception of the laser beam, which is the reflection time of the laser beam. Based on the speed of the light and the reflection time, the timer can calculate the round trip distance of the laser beam from emission to the target.

Finally, the rangefinder displays the measured distance data on a monitor for the user to view.

The operating principle of a laser rangefinder is based on the relationship between the speed of light and the reflection time of light. The speed of light in a vacuum is a known constant of about 3 x 10^8 metres per second. By measuring the reflection time of the laser beam, the distance travelled by the light can be calculated, thus indirectly obtaining the distance between the target and the laser rangefinder.

To summarise, a laser rangefinder works by using the relationship between the speed of the laser beam and the reflection time of the beam to measure the distance. It measures the distance between the target and the laser rangefinder indirectly by transmitting the laser beam through the laser, receiving the reflected light signal at the receiver, and calculating the light propagation time through a timer.

Previous

Next

Previous

Next

News