A laser rangefinder is a rangefinder that uses a laser beam to determine the distance to an object. The most common form of laser rangefinder operates on the time of flight principle by sending a laser pulse in a narrow beam towards the object and measuring the time taken by the pulse to be reflected off the target and returned to the sender. Due to the high speed of light, this technique is not appropriate for high precision sub-millimeter measurements, where triangulation and other techniques are often used.
Time of flight – this measures the time taken for a light pulse to travel to the target and back. With the speed of light known, and an accurate measurement of the time taken, the distance can be calculated. Many pulses are fired sequentially and the average response is most commonly used. This technique requires very accurate sub-nanosecond timing circuitry. Multiple frequency phase-shift – this measures the phase shift of multiple frequencies on reflection then solves some simultaneous equations to give a final measure. Interferometry – the most accurate and most useful technique for measuring changes in distance rather than absolute distances.
The pulse may be coded to reduce the chance that the rangefinder can be jammed. It is possible to use Doppler effect techniques to judge whether the object is moving towards or away from the rangefinder, and if so, how fast. The precision of the instrument is determined by the rise or fall time of the laser pulse and the speed of the receiver. One that uses very sharp laser pulses and has a very fast detector can range an object to within a few millimeters.
Despite the beam being narrow, it will eventually spread over long distances due to the divergence of the laser beam, as well as due to scintillation and beam wander effects, caused by the presence of air bubbles in the air acting as lenses ranging in size from microscopic to roughly half the height of the laser beam’s path above the earth.
These atmospheric distortions coupled with the divergence of the laser itself and with transverse winds that serve to push the atmospheric heat bubbles laterally may combine to make it difficult to get an accurate reading of the distance of an object, say, beneath some trees or behind bushes, or even over long distances of more than 1 km in open and unobscured desert terrain.
Some of the laser light might reflect off leaves or branches which are closer than the object, giving an early return and a reading which is too low. Alternatively, over distances longer than 1200 ft (365 m), the target, if in proximity to the earth, may simply vanish into a mirage, caused by temperature gradients in the air in proximity to the heated surface bending the laser light. All these effects have to be taken into account.
Laser rangefinders are divided into four classes and several subclasses. Laser rangefinders available to consumers are usually laser class 1 or class 2 devices and are considered relatively eye-safe. Regardless of the safety rating, direct eye contact should always be avoided. Most laser rangefinders for military use exceed the laser class 2 energy levels.
Types of laser rangefinders:
Laser rangefinders are divided into handheld laser rangefinders and telescope laser rangefinders.
1. Handheld laser rangefinder: The measuring distance is generally within 200 meters, and the accuracy is about 2mm. This is a laser rangefinder that is currently widely used. Functionally, in addition to measuring distance, it can also calculate the volume of the measured object.
2. Cloud service laser rangefinder: The measurement data on the laser rangefinder is transmitted to mobile terminals such as mobile phones, tablets, etc. in real time via Bluetooth; the data can be transmitted to the cloud server through wifi networking, and shared with remote construction partners in real time Measurement data.
3. Telescopic laser rangefinder: The measuring distance is generally about 600-3000 meters. The measuring distance of this kind of rangefinder is relatively long, but the accuracy is relatively low, and the accuracy is generally about 1 meter. The main application range is long-distance measurement in the field.
Laser rangefinders are used extensively in 3-D object recognition, 3-D object modelling, and a wide variety of computer vision-related fields. This technology constitutes the heart of the so-called time-of-flight 3D scanners. In contrast to the military instruments, laser rangefinders offer high-precision scanning abilities, with either single-face or 360-degree scanning modes.
A number of algorithms have been developed to merge the range data retrieved from multiple angles of a single object to produce complete 3-D models with as little error as possible. One of the advantages that laser rangefinders offer over other methods of computer vision is that the computer does not need to correlate features from two images to determine depth information as in stereoscopic methods.
Laser rangefinders used in computer vision applications often have depth resolutions of tenths of millimeters or less. This can be achieved by using triangulation or refraction measurement techniques as opposed to the time of flight techniques used in LIDAR.
Special laser rangefinders are used in forestry. These devices have anti-leaf filters and work with reflectors. Laser beam reflects only from this reflector and so exact distance measurement is guaranteed. Laser rangefinders with anti-leaf filter are used for example for forest inventories.
They are virtually indispensable in the military equipment of special units or armed forces: Laser rangefinders for professional use. Particularly in critical situations, precise distance measurement is essential for reliable firearm targeting. Laser rangefinders are therefore military standard equipment worldwide with many defense forces.
Rangefinders provide an exact distance to targets located beyond the distance of point-blank shooting to snipers and artillery. They can also be used for military reconnaissance and engineering. They are virtually indispensable in the military equipment of special units or armed forces, Particularly in critical situations, precise distance measurement is essential for reliable firearm targeting. Laser rangefinders are therefore military standard equipment worldwide with many defense forces.
You need a military-grade laser range finder to operate in extreme conditions. Handheld military rangefinders operate at ranges of 2 km up to 25 km and are combined with binoculars or monoculars. When the rangefinder is equipped with a digital magnetic compass (DMC) and inclinometer it is capable of providing magnetic azimuth, inclination, and height (length) of targets. Some rangefinders can also measure a target’s speed in relation to the observer. Some rangefinders have cable or wireless interfaces to enable them to transfer their measurement(s) data to other equipment like fire control computers. Some models also offer the possibility to use add-on night vision modules. Most handheld rangefinders use standard or rechargeable batteries.
If the electric sighting system is used in conjunction with a laser rangefinder, it can improve the anti-interference ability of the fire control system, find targets in radio silence, and increase the power of maneuvering air combat at close intervals by 50%.
The more powerful models of rangefinders measure distance up to 25 km and are normally installed either on a tripod or directly on a vehicle or gun platform. In the latter case the rangefinder module is integrated with on-board thermal, night vision and daytime observation equipment. The most advanced military rangefinders can be integrated with computers. To make laser rangefinders and laser-guided weapons less useful against military targets, various military arms may have developed laser-absorbing paint for their vehicles. Regardless, some objects don’t reflect laser light very well and using a laser rangefinder on them is difficult.
The Army is eyeing this advanced fire-control system for its next-generation squad weapon
Army modernization officials have selected a Wisconsin-based optics firm to make advanced fire-control prototypes capable of equipping the service’s Next Generation Squad Weapon (NGSW) with a 1,000-meter laser range finder and a ballistic computer to calculate the bullet’s path to the target, according to an April 2020 news release from Vortex Optics.
The 1-8×30 Active Reticle Fire Control is a variable power, direct-view, first focal plane riflescope — meaning that the reticle is located in front of the magnification lens to allow the reticle to increase in size as the shooter increases the magnification level. Vortex officials maintain the prototype’s “1km-capable laser rangefinder, state of the art on-board ballistic engine, atmospheric sensor suite, and programmable active matrix micro-display … delivers a true multi-mission fire control enabling everything from [close-quarter battle] to designated marksmanship at the extents of the NGSW’s effective range,” according to the release.
“For the soldier in the field, that means the freedom to devote their entire focus downrange,” Sam Hamilton, chief technical officer at Vortex Optics, said in the release. “End-users will no longer need to leave their field of view to consult separate rangefinders or ballistic calculators, slowing them down and compromising their situational awareness.”
In Nov 2020, the U.S. Army awarded an initial delivery order to L3Harris Technologies for rifle-mounted multifunction laser devices intended to support target handoff operations. L3Harris said Thursday it will produce more than 1,100 updated Small Tactical Optical Rifle-Mounted Micro Laser Rangefinder systems for the military service under a potential $215 million contract announced last year.
FAMILY OF WEAPON SIGHTS — CREW SERVED (FWS-CS)
The U.S. Army is developing new weapon sights to go on machine guns and grenade launchers called the Family of Weapons Sights-Crew Served (FWS-CS) to enhance battlefield accuracy. The Family of Weapon Sights – Crew Served (FWS-CS) will mount to the M240 Medium Machine Gun, the M2 .50-Caliber Machine Gun and the MK19 Grenade Machine Gun and will provide the Soldier with High-Definition (HD) infrared (thermal) imagery in all weather conditions, under all lighting conditions and through obscurants. The FWS-CS will also integrate an HD day camera, a laser rangefinder and a wireless Helmet Mounted Display (HMD).
The sight also includes thermal and infrared imaging to enable its use at night or in dust, smoke, or haze. The FWS-CS HD thermal sensor and HD day camera will provide Soldiers with a long-range capability for crew-served weapons. The FWS-CS integrated laser rangefinder will support a ballistic crosshair that shifts based on the target range, enabling Soldiers to get first bursts on target.
What sets the FWS-CS apart is its ability to synchronize with other systems and broadcast live images from the weapon sight to other head-borne systems over battlefield networking. The FWS-CS wireless HMD allows the Soldier to receive weapon sight imagery while behind protective armor and when using a weapon system with the Objective Gunners Protection Kit. The sight also is a high-definition camera. Its built-in camera could connect to the operator’s heads-up display to enable firing the weapon without leveling the scope to his own eyes.
Military laser rangefinder market
Military Laser Rangefinder Industry
The “Global Military Laser Rangefinder Market 2022-2026” report has predicted that military laser rangefinder market is poised to grow by $4.67 billion during 2022-2026, progressing at a CAGR of 6.70% during the forecast period.
A rangefinder is an instrument used to assess the distance and elevation of distant objects. The tool has its application in a number of areas such as navigation, target correction, survey, photo focus, and so on. The market is segmented as laser and ultrasonic based on the type. During the forecast period, the laser segment is expected to capture a larger market share, powered by the increasing use of such rangefinders in different commercial applications.
Geographically, Rangefinder Market Report is segmented into several key regions: Europe (Germany, UK, France, Italy, Russia and Turkey etc.), Asia-Pacific (China, Japan, Korea, India, Australia, Indonesia, Thailand, Philippines, Malaysia and Vietnam) , South America (Brazil etc.), Middle East and Africa (Egypt and GCC Countries)
Due to the increasing demand for rangefinders in countries such as the U.S. and Canada, North America is expected to be the largest market for rangefinders in 2018. It is also expected that the rangefinder market in Europe and the Asia Pacific will see high growth due to the rapid modernization and rise in defense equipment upgrades in these regions by governments.
North America dominates the global market and during the forecast period is likely to grow at a remarkable rate. The involvement of major companies, such as Lockheed Martin Corporation, Northrop Grumman Corporation, and FLIR Systems Inc., contributes to this region’s global market supremacy. In addition, the US Department of Defense (DoD)’s increasing military spending on miniature military rangefinders has resulted in a significant increase in demand in this area in recent years. The Asia-Pacific market for military laser rangefinders is expected to be the fastest-growing region.
At present, the market is developing its presence and some of the key players from the complete study are Elbit Systems, Leonardo, Lockheed Martin, Northrop Grumman, Saab, Thales Group, Safran Electronics & Defense, L3 Advanced Laser Systems Technology, FLIR Systems, Jenoptik.
New opportunity expected to boost military laser systems market include increasing demand for the directed-energy weapons in various military applications. These systems are power-efficient and compact and can strike limitless bullets with speed of light. They are correspondingly capable of stopping land, air, and sea targets in path. Thus, they are anticipated to prove as complementary weapon in battlefields exactly effective in disabling drones and rockets. Leading companies including Raytheon International Inc. and the Lockheed Martin Corporation among various others are assimilating innovative technologies such as the auxiliary technologies and sophisticated beam control in the systems to deliver defensive as well as violent capabilities against rising threats to military forces and the infrastructure making these systems, commonplace.
Some of the leading military laser rangefinder market vendors include Elbit Systems Ltd., Jenoptik AG, LAP GmbH Laser Applikationen, Leonardo Spa, Lockheed Martin Corp., Northrop Grumman Corp., Saab AB, Safran SA, Teledyne FLIR LLC, and Thales Group.
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