How Does A Laser Distance Meter Work
A laser distance meter, like the name suggests, is a distance measuring device that employs a laser beam to gauge distances in terms of their length, height, and width and also measures volume and area. Some of the laser distance meter devices can also measure angles.
When compared to traditional measuring devices such as a measuring tape, a laser distance meter offers a greater range of measuring. Some of the latest devices on the market can even measure up to 600 feet, whereas a traditional tape can measure only up to 25 feet. This is one of the major reasons why contractors, appraisers, and others highly use a laser distance meter in the construction business.
In addition to its standard advantages of precision and accuracy, a laser meter device also provides greater speed and ease of handling. The processor of the device quickly turns the distances measured into area and volume. Therefore, there is no hassle of manual calculations!
What are the Parts of a Laser Distance Meter?
A laser distance meter is a rectangular measuring device that consists of the following parts:
- Beam Outlet: This part of the laser distance meter is responsible for emitting the laser beam, and the beam later travels through space and back to the device with the accurate measurement.
- Display: Since the laser distance meter is an electronic product, the measured distances are displayed on the backlit display screen.
- Controls: Different types of laser distance meters on the market have different controls which the operator can manually handle.
- Battery: The battery of the device is responsible for powering it and is located at the back of the laser distance meter.
What is the Working Mechanism of a Laser Distance Meter?
A laser distance meter efficiently and accurately measures the distances between two points by calculating the time it takes for the laser beam to hit the target and return back to the device. This principle is called “time of flight” and this method of measurement is known as pulse measurement.
Now that you know what the principle and the method of operation of laser distance meters is called, it is time to throw some more light on the device’s operating principle. When you point the laser distance meter at a point, it emits a laser beam at the target. This laser pulse then reflects or bounces off the said target and returns back to the laser distance meter. As stated above, this principle is called the “time of flight”.
It is based on the fact that the laser beam travels through the atmosphere of the Earth at a constant speed. Inside the distance meter is present a computing device that quickly measures the distance to the said target. Therefore, laser distance meters are also known as laser range finders or range finders.
Do you know how the computing device inside a laser distance meter calculates the distance between the target and the meter? It does so by a particular formula which is D = ct/2. In this formula, c denotes the speed of light, t denotes the time taken by the laser beam to complete the roundabout trip between the meter and the target, and D denotes the distance between the meter and the target.
Due to the constant height speed of the pulse and its focus, this calculation is extremely accurate over a larger distance. However, it does lose its accuracy over too small or too far distances.
What are Some Things to Consider About Laser Distance Meters?
Can you guess what determines the accuracy of the distance measured by the laser distance meter? Yes, you guessed it right. It is dependent on the laser beam pulse that returns back to the sending device. Despite having high and narrow energies, lasers are also subject to certain atmospheric distortions just like the normal white light.
Such atmospheric distortions make it quite difficult for the laser beam to accurately measure distances when objects are near greenery or when objects are farther than 1km in a deserted terrain. Furthermore, another point worthy of noting here is that different objects reflect light to different degrees.
Therefore, an object made of a material that absorbs or diffuses the light source can deter the measurement accuracy of a laser distance meter. In such a case, you must use a laser distance meter based on the phase shift method.
What is the Optical Design of Laser Distance Meters?
For enhanced reliability and accuracy, laser distance meters work on minimizing the background light. An excessive background light interferes with the distance measurement because the sensor might mistake some of the excessive background light for the laser pulse reflected by the object. This can give a false reading.
In such cases, manufacturers use receiving optics wherein a combination of split beam frequencies, narrow bandwidth filters, and an extremely small iris is used to block out the excessive background light.
Should You Buy Laser Distance Meters?
A traditional distance meter can prove to be useful when you’re measuring a short distance or when you need to simulate the object space physically. This is probably the reason why several people in the construction business, such as bricklayers, still use it.
Another point to bear in mind is that to make full use of the laser distance meter, you need to have an object that is capable of reflecting the laser light. That said, it is of great advantage in situations wherein the operator has to measure the distance all by himself.
Furthermore, such devices are extremely important for the safety of the workers and are capable of reaching even the most inaccessible points. This eliminates potentially hazardous dangers and keeps the construction workers safe and sound!