What Is a Laser Rangefinder & How It Works

It is no secret that the best shots occur when you are able to accurately zoom into your target. Be it a shotgun or a camera, the secret lies behind correctly getting the distance between you and your target.

That is why to make things easier, man invented the laser range finder. The device is able to pinpoint an exact position to give you the best shot. What exactly is a Laser Range finder? To understand the laser rangefinder, it is important to first understand what the range finder is. So here goes.

A rangefinder is a device that is used to measure the distance between a person and a target object. The process by which this is done is called ranging. There are several methods of range finding as listed below: -

  • Ultrasonic range finding
  • Radar range finding
  • Lidar range finding
  • Sonar range finding
  • Laser range finding
  • List Element

Laser range finding is applicable in surveillance, navigation, photography, golf, and ballistics.

Golf: This technology is increasingly becoming popular among amateur golfers as a method of improving the game. Laser rangefinders are used to measure yardage, gauge slope and measure wind of a shot. The player aims the reticle at the flagstick and presses a button to obtain the yardage.

Ballistics: Rangefinders are typically used for long-distance shooting to measure distance before shooting. The laser rangefinder, however, displays a luminous dot that may be a giveaway to alert the target.

Surveillance: This rangefinder is being used to survey forests for instance. Here the rangefinders are used with special devices that filter leaves.

Photography: Laser rangefinders play a great role in assisting photographers to focus on their targets. This enables them to get the perfect shots aimed precisely. 

How Laser Rangefinder And Amp Work

You are probably wondering how the laser rangefinder and amp works. Well despite all the fancy technology that seems to surround the laser range finder, it operates on a rather simple concept. It is closely related to the autofocus cameras in that the cameras project invisible laser beams to the object. It is then reflected back and detected by a sensor on the camera. A Laser Rangefinder works in a similar manner. 

The LFR uses a beam to determine the distance of an object using the principle of Time of Flight. The laser pulse beam sent to the object measures the time taken for the pulse to be reflected back to the rangefinder. Simply put, Laser Rangefinders (LFR) use an invisible infrared laser beam and a computer chip to calculate distances. This beam is aimed at the target. 

As soon as the beam hits the target, it is reflected back to the range finder. The computer chip in the LRF uses a high-speed digital clock to calculate the time taken to hit the target. It is then displayed on the screen of the LRF. The readings come almost instantaneously as the laser beam moves with the speed of light. 

LRFs work extremely quickly, they fire pulses in multiples at the target audience and decipher the reflected beams to determine the correct distance to report. Of course, there will be other readings from surrounding objects but the LRF will use an algorithm to determine the most relevant data and give a distance. Because of the high level of technology used, the readings are accurate and in more sophisticated LRF’s the distances can be calculated to inches. 

It is important to note that the LFRs work differently depending on the kind of range that they offer. How good the LFR is will depend not on the model but rather how uniform, how tight and the capability of the sensor. In essence, a sensor with the ability to filter information and sense low light will perform well when it comes to handling high ranges. 

Thus, not all LFRs perform equally. Also, the angle at which you are targeting in relation to where you are is a determinant in the performance of the LFR. It is pertinent that you compensate for the elevation difference to get proper readings. Other factors that may affect the performance of the LFRs are:

Target spotting ability – this will be determined by the quality of the optics and magnification.

Beam focusing ability- this basically has to do with the beam divergence. This refers to how focused the beam can be on the desired object. Also the quality of the laser including the pulse transmission, wavelength, sharpness etc. 

Size of the receiver aperture- this refers to the size of the receiving optic capturing the return readings before relaying them to the sensor. The bigger the size the more the information that is captured and the more accurate the readings. 

 Result analysis – this is how the unit interprets the received readings. The smarter the unit the more accurate the readings. 

Environmental factors may also influence the performance of your LRF. To start with the speed of light is influenced when transitory through different types of matter. Air density, humidity and temperature affect the speed of light. Other more pertinent factors that affect the LFR are smog, fog, dust, and rain. Some LRFs are made with rain and Fog Modes that help correct the imbalance.

The reflectivity of surfaces also plays a big part in how your LFR performs. Hard, shiny, smooth and bright colored targets generally give better reflections and thus better readings. This is compared to dull surfaces that may tend to offer a minimal reflection. Color has a noticeable effect. Dark and dull colors absorb light thus reflecting back less. As a rule of thumb the brighter and shinier the object the better the readings.


Laser rangefinders have changed the way that distance calculation has changed. Contrary to popular belief, using a laser range finder is actually very simple. However, it may take you a few tries to get the hang of it. 

You just need to know the buttons the t you need to press when targeting and of course you must know how to read the display. It is of utmost importance to ensure that you select a rangefinder for your specific needs. The market is filled with rangefinders designed for different needs e.g. fishing, golf, surveillance, ballistics etc.  

And as always make sure you properly store your range finder.

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