Electronic rangefinders with digital microprocessors, which have replaced tape tape measures and metal meters, significantly reduce labor costs when carrying out measuring work. This is not only an expensive, eye-catching toy that can be used to solve current everyday problems, but also a professional tool that improves the quality and productivity of measurement work at the stages of assessment, design and construction.

Functionality

The main function of laser rangefinders is to carry out remote linear measurements. Depending on the built-in algorithms, you can also automatically calculate the perimeter, the volume of enclosed spaces, also calculate distances to distant landscape objects and make angular and diagonal measurements.

Some models are equipped with a tracking function, which allows you to make markings at a certain distance from the object. Laser rangefinders may have a continuous measurement option, which allows you to set a specified distance from the zero point by directing the beam along a specific line.

Another mode allows you to calculate the sides of a trapezoid (for example, a sloping roof), based on measurements of the other three parameters (respectively, the height of the walls and the horizontal floor).

The Pythagorean theorem option allows you to make an indirect calculation of hard-to-reach segments, obtaining the size of one of the sides of the triangle based on the length of one of the legs and the hypotenuse. A notepad for saving and data storage function is another advantage of electronic measuring instruments.

Types of rangefinders based on operating principle

Phase rangefinders are highly accurate but have limited range. Calculations are made based on the phase shift of the directed and reflected laser wave.

The pulse rangefinder calculates the derivative of the time of passage of the laser beam and the speed of light. This principle provides maximum measurement range and is most suitable for use in open areas.

Special devices correct signal processing, ensuring accurate measurements. Pulse rangefinders, due to their complicated design, are more expensive than phase ones.

Selection options

The first parameter that will help you decide which rangefinder is best suited for a specific request is the maximum range. Then you need to pay attention to the power of the microprocessor, which determines the speed and functional characteristics of the device.

The measurement accuracy of laser rangefinders ranges from 1-1.5 mm, and is not a decisive indicator of choice. Errors in measurements can also be caused by external factors, which are eliminated by additional measures, for example, installing targets to correct specific surfaces with increased absorbing or reflecting effects.

Glasses with light filters and models designed for various weather conditions can solve professional problems of any complexity. The price class depends on the set of options, configuration features and the authority of the manufacturer.

Additional devices

Various models of rangefinders, as judged by a selection of photos, look almost the same: the front panel is equipped with a display and control buttons, on the front there is an emitter and receiver, and in some cases an optical device.

The accuracy of the measurements depends both on the technical parameters and on the correct location of the rangefinder, so it is recommended to use a bubble level to check the zero reading.

Some models have such a built-in device that makes it easier to adjust the vertical and horizontal position. Professional modifications for topographic work are equipped with an optical visor.

Retractable stops and clamps are provided for mounting on ground surfaces or tripods. The presence of removable batteries, an energy consumption indicator and automatic shutdown greatly facilitates use. Modern models have the ability to connect to a computer and use a removable memory card.

The protection class of the housing and the quality of the display are selected depending on the external conditions in which the device will be used.

Safety regulations

Instructions for certain rangefinder models contain a set of rules for using and storing the device. In addition to the specific requirements determined by design features, all laser devices cannot be disassembled and repaired outside the walls of specialized workshops.

The device must be stored in a special case, to prevent overheating or hypothermia, and to protect it from impacts and falls. When working with a rangefinder, it is prohibited to direct the beam at people and animals.

Photos of laser rangefinders

Introduction

Rangefinder- a device designed to determine the distance from the observer to the object. Used in geodesy, for focusing in photography, in sighting devices for weapons, bombing systems, etc.

Laser ranging is one of the first areas of practical application of lasers in foreign military equipment. The first experiments date back to 1961, and now laser rangefinders are used in ground-based military equipment (artillery, such), and in aviation (rangefinders, altimeters, target designators), and in the navy. This equipment has been combat tested in Vietnam and the Middle East. Currently, a number of rangefinders have been adopted by many armies around the world.

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Types of rangefinders

Rangefinder devices are divided into active and passive:

§ active:
§ sound rangefinder
§ light rangefinder
§ laser rangefinder
§ and etc.
§ passive:
§ rangefinders using optical parallax (e.g. rangefinder camera)
§ rangefinders that use object-to-sample matching
§ and etc.

The operating principle of active type rangefinders is to measure the time it takes for the signal sent by the rangefinder to travel the distance to an object and back. The speed of signal propagation (the speed of light or sound) is considered known.

Measuring distances with passive type rangefinders is based on determining the height h of an isosceles triangle ABC, for example, using the known side AB = l (base) and the opposite acute angle b (the so-called parallactic angle). For small angles b (expressed in radians)

One of the quantities, l or b, is usually a constant, and the other is a variable (measurable). Based on this feature, a distinction is made between rangefinders with a constant angle and rangefinders with a constant base.

Laser rangefinder

Laser rangefinder is a device for measuring distances using a laser beam. sighting rangefinder

Widely used in engineering geodesy, topographical surveys, military affairs, navigation, astronomical research, and photography.

A laser rangefinder is a device consisting of a pulsed laser and a radiation detector. By measuring the time it takes the beam to travel to the reflector and back and knowing the speed of light, you can calculate the distance between the laser and the reflecting object.

Fig.1

The ability of electromagnetic radiation to propagate at a constant speed makes it possible to determine the distance to an object. Thus, with the pulse ranging method, the following relationship is used:

Where L- distance to the object, c- speed of light in vacuum, n- refractive index of the medium in which the radiation propagates, t- the time it takes for the impulse to travel to the target and back.

Consideration of this relationship shows that the potential accuracy of range measurement is determined by the accuracy of measuring the time it takes for the energy pulse to travel to the object and back. It is clear that the shorter the impulse, the better.

A rangefinder is a device that is designed to determine the exact distance from an observer to a specific object. The device is simply necessary in engineering geodesy, construction of transmission lines and communications, agriculture, tourism, navigation, military affairs...

Classification of ranging devices

When and where did the first range meters appear? This device first went on sale in 1992 in the West, but its cost reached several thousand dollars. And only four years later these devices became available to a wider range of users. Then many companies began to work in this direction. And today there are quite a few varieties of this instrument, the most accurate ones use the laser principle in their work; a well-known model is the Leica rangefinder; the range also includes other devices for similar purposes, for example, those using lasers.

What is the principle of operation? Active type models measure distance using the time it takes a sent signal to travel to the object and back. The speed with which this signal propagates is, of course, known in advance (sound and light speed). Determining the distance using passive versions of the device is based on calculating the height of an isosceles triangle. Active ones are divided into three types: sound, light, laser. And there are two passive ones: optical and filament.

Active type rangefinders - studying the operation of tools

Sound models measure the distance to objects that reflect sound waves. They work on the principle of an echolocator, that is, first a short sound pulse is emitted, which has a very high frequency. Then the microphone is turned on, and the time is counted during which the sound pulse will return back, reflected from some object. When the returned signal reaches the sensor, the result will be known. Light types of distance measuring devices use light modulation in brightness with a constant or variable frequency.

The distance is calculated by the phase difference between the reflected and sent light. This requires the presence of complex electronic and electrical devices in the device. It was with the help of light models that the exact distance from the Earth to the Moon was established. Laser instruments include the main elements of the device - a reflector and an emitter. Using special function keys, you can set a reference point and use all the software capabilities of the device. Also, some models are equipped with additional functions - a reflective panel for testing, air temperature measurement, selection of a measurement system, automatic shutdown setting, battery indicator.

When working with a laser device, the assistance of a second person is not required, as, for example, is the case with. In order to calculate the distance to a certain object, you need to point a laser beam at it. The device measures the time it takes for a beam to travel from it to an object and, after being reflected, to return back. As a result, calculations are made and the data is displayed on the screen. You can measure both horizontal and vertical planes. Using a laser rangefinder, you can also measure the volume of a room and its total area.

In addition, such a device provides a unique opportunity to measure only a certain fragment of the wall, and not its entirety. You can also define the width and height of an object.

A huge advantage is that the laser device can calculate the average value of several measurements, and the accuracy will be at a very high level. It is also possible to find out the area of round objects, and not just rectangular or square ones. If the room has a sloped ceiling, then the tool will determine not only the area, but also the angle of inclination and the length of the slope. All measurements can be carried out at a distance of up to 200 meters. If you need the device to measure only rooms, it will be enough to purchase a device whose measurement range does not exceed 50 meters. If you are going to work over long distances, you should also use a tripod and a reflective plate, this will allow you to get more accurate results. But not all models can be mounted on a tripod; this needs to be clarified with the seller.

The main characteristics of laser instruments depend not only on the design, for example, the measurement range depends on the power of the radiation source and on external operating conditions, for example, lighting will affect the range. It is worth noting separately that it decreases if measurements are carried out in the open air. Household models have small errors, and these errors increase when measuring over large distances. But even these types of laser devices are relatively expensive.

We measure range using passive methods

Optical rangefinder can be of two types - stereoscopic and monocular. Despite the fact that they differ in the design of the parts, their basic circuit is the same, in addition, the principles of operation are identical. Using two known angles of a triangle, as well as one known side, its unknown side is determined. Two telescopes construct an image of the object. The object appears to be seen in different directions. In addition, such devices can be either full-field overlay or half-field overlay - the upper half of the image from one telescope is combined with the lower half of the other.

Monocular models are a type of optical, they also work on the principle of combining images, and are very often built into photographic equipment to obtain a sharper image. The advantages of monocular rangefinders are that there is no need for precise horizontal aiming, and the image during measurement is shifted in both the right and left fields. The disadvantages of monocular devices include high fatigue of the operator, since the work is done with one eye, it is also practically impossible to work with moving objects, and the object needs to have a clear generatrix, which is located at ninety degrees to the field dividing line, otherwise the measurement accuracy will decrease significantly.

Stereoscopic models are also a type of optical and have a double telescope. There are marks in the focal plane, and the image of the object is combined with the image of these marks, the distance is completely proportional to the displacement of the compensator. The main advantage of a stereoscopic instrument over a monocular instrument is more accurate distance measurements. They are used to determine the range, as well as the flight altitude and its angular coordinates. The most powerful stereoscopic devices are capable of operating at distances of up to 50,000 meters; as for measuring altitude, the numbers here are slightly smaller - up to 20,000 meters.

The thread version of range finders is the simplest type of instrument for this purpose, having a constant parallax angle, which is why you can make such a range finder with your own hands if you suddenly need to measure the range, but you don’t have time to go shopping, or you’re sorry for the money. It can detect distances up to 300 meters. This device uses a leveling rod with centimeter divisions as a base, and special lines are visible in the field of view of the pipe. How it works: to accurately determine the distance, the number of divisions that are between the lines is counted, and the desired distance will ultimately be the distance in meters. The thread device has a very simple design and a very simple operating principle, it is also able to calculate the distance without much error. But the electronic rangefinder still wins in terms of accuracy.

Without which it is impossible to even imagine any construction or repair work, regardless of the scale and level of complexity - this is without taking measurements and without making markings. The accuracy and precision of such operations always become the key to the quality and durability of the resulting result. Therefore, the measuring instrument is always unconditional an important component of any owner’s tool arsenal houses or apartments.

One of the basic measurements is always the determination of distances and linear dimensions of objects. These values, in turn, become the starting points for calculations, for example, areas and volumes. For a long time, for these purposes, in addition to ordinary rulers, a cord with marks applied to it, corresponding to units of length, was used. A regular tape measure is the same tool, but instead of a cord, a metal, fabric or plastic tape with a printed scale is used. It is quite convenient and accurate, but if the distances being measured are small, or if there is an assistant when taking measurements. But alone, and at considerable lengths, you have to “split” the measured area into smaller ones, which, of course, affects both the time it takes to complete the work and its accuracy.

It’s a different matter if you have a compact and accurate device at your disposal - a laser rangefinder (or, as it is often called, a laser tape measure). Performing measurements takes a matter of seconds, and the accuracy of the results obtained is beyond praise. In addition, modern tools of this type often have additional functionality - they allow you to quickly carry out the necessary calculations, so to speak, in “field conditions”. The variety of models on sale is very wide, so before purchasing it would be useful to get information about which laser rangefinder is better.

What is the laser rangefinder based on?

There is no doubt that all high-tech developments are primarily “tested” in the military sphere. When the author of these lines entered the Odessa Higher Artillery School back in 1981, the first reconnaissance skills were mastered on the stereoscopic rangefinders DS-1 and DS-2. But, by the way, very few could work for them with a sufficient degree of accuracy. Therefore, the study of the DAK-1 laser rangefinder, which in those years was considered a secret weapon, was a great “revelation” for us.

Our joy was only overshadowed by the fact that delivering the rangefinder to the observation post turned into a considerable ordeal. The set consisted of two heavy metal boxes and a tripod. Therefore, having sweated a lot in class, we built bold dreams that someday such equipment would become much more compact, and would almost be an item of individual equipment for an artillery reconnaissance officer.

And so it happened, but much later.

Over time, military developments migrated to the public sphere, in particular to construction. And the development of technology has led to the fact that a device of this operating principle can now be easily bought in a store.

Of course, laser rangefinders that are offered to consumers today are still inferior in capabilities to modern military equipment. But they are not required to take measurements amounting to many hundreds of meters and kilometers. But the operating principle of both is very similar.

Distance measurement is based on the ability of an optically opaque surface to reflect light directed at it. That is, if you direct a powerful light pulse generated by a built-in emitter (laser) at the “target”, and then detect reflected signal, then, knowing the speed of light, you can determine the distance to the object.

But in reality, the measurement is performed somewhat differently. The fact is that the speed of light is enormous, and at small measured distances one has to operate with extremely short time intervals, measured in nanoseconds. Making a compact timer that could very accurately measure such small intervals is a very difficult and expensive task. Therefore, construction rangefinders use the principle combsphase shiftreflectedinfrared light pulse.

When you press the start button, the laser rangefinder emitter generates a light beam of a strictly defined wavelength and frequency. The beam directed at the desired point is reflected from it and received by the photodetector of the device. The built-in microprocessor compares the phases of the beam at the exit from the device and the reflected one. Since the frequency and wavelength of the radiation are known, the distance traveled by the beam can be estimated with high accuracy. The error is usually no more than half the wavelength, which gives an error within 1÷1.5 mm per meter of measured distance, which is considered an excellent indicator for construction conditions.

There are other types of rangefinders. Thus, powerful devices capable of accurately assessing distances of hundreds or more meters are equipped with a powerful pulsed laser that does not scatter the light beam, and a high-precision timer capable of measuring time intervals with the highest accuracy. But the cost of such devices is very high, and they are not used in domestic conditions.

The principle of reflection of sound waves is also used to measure range. Such ultrasonic “roulettes” are commercially available, they are designed to work for short distances. Judging by the reviews, they are not particularly praised by experienced builders, although this is not a categorical judgment.

But in this article, we will further focus only on phase-type laser rangefinders.

The device of a compact laser construction rangefinder

The shape of most modern laser construction rangefinders closely resembles the mobile phones of the early 2000s. That is, they are quite compact, easily fit in a pocket of work clothes, and are not at all difficult to use in construction or home renovation conditions.

As a rule, the device body is made of impact-resistant plastic and has a shape that is comfortable to hold in the palms of your hands. Since the rangefinder is designed to operate under construction or repair conditions, that is, in possible heavy dust and in any weather, the housing is provided with very serious protection - usually not lower than IP-44. Special shock-absorbing elastic linings on the body protect the device from damage if accidentally dropped.

Inside the case there is a light pulse generator (laser), an optical circuit for transmitting and receiving a signal, a microprocessor unit programmed to measure distances and perform a number of other useful functions.
Few people would probably think of the idea of disassembling this device, so we will limit ourselves to its external structure.

At the front end of the device, “windows” of the pulse emitter and photodetector are always visible. In some models, a compact optical view camera may also be located there.

On the front panel of the rangefinder there is a display on which the current settings of the device and the results of the measurements are displayed. Usually a monochrome liquid crystal display is used, although you can also find devices with color displays, although this, frankly speaking, seems like overkill.

Near the display there are rangefinder control buttons. Among them, of course, the start button, that is, the measurement button, always stands out. But most modern laser roulettes are equipped with a number of interesting useful functions - access to them or programming the device for a specific operating mode is also done using buttons, and the procedure is described in detail in the attached instructions.

There are also devices with touch “buttons” displayed on the display. True, how convenient it will be to work with them with dirty hands, which often happens during repair or construction, is not entirely clear.

For precise aiming of the device, if measurements are carried out at long distances, or due to the illumination characteristics of the object, the laser point may become invisible, additional capabilities can be provided to direct the beam precisely to the target. So, some rangefinders have an optical sight, similar to what we are used to seeing on cameras. The visor can be built-in or removable. The degree of optical approximation of the object in the viewfinder may also vary. If in professional-class devices designed to measure long distances, the magnification can reach up to 12 times, then in simpler models the sights are simpler, with 6–8 times magnification.

Some modern models are even cooler. The display of such devices through the built-in video camera can display image of the object to which the range is determined, with an aiming crosshair that allows you to accurately indicate the desired point.

On the back of the body of many models there is a folding or retractable stop (bracket or pin). This is a very convenient option that allows you to measure length from hard-to-reach points. For example, you can rest the rangefinder in the corner between the walls to measure the diagonal, etc.

Many rangefinders are equipped with a threaded bushing or other mechanism that allows the device to be fixed, for example, on a tripod, in order to accurately check distances in different directions from one point.

Bubble levels are often provided on instrument cases to allow the rangefinder to be positioned correctly vertically or horizontally.

The device may be equipped with a port for cable connection to a computer and have a slot for a memory card.

At the bottom of the case there is usually a battery compartment or a connector socket for connecting a charger (if power is supplied from built-in batteries).

The device may include a case and straps for safer use of the device. A good addition to the set can be special targets that allow you to set the length measurement point as accurately as possible, for example, if it has not yet been set by any object capable of reflecting a light beam (often happens when laying out on the ground).

Criteria for evaluating a laser rangefinder when choosing

The variety of laser rangefinders presented in stores is quite wide. And in order not to overpay or encounter insufficient built-in functionality of the device, it is necessary to have a clear understanding of the scope of its application in advance.

To carry out large-scale construction work on a site related to breaking out and marking the territory, linking objects, etc., apparently, it makes sense to purchase a device with an emphasis on the maximum measurement range. Thus, many professional or semi-professional class rangefinders (the division is fairly arbitrary) can operate at distances over 40÷50 meters. If the potential owner is going to use the device for internal repairs, then there is no point in chasing range. Indicators less than 40 m will be sufficient.

But the accuracy of the measurements taken is always important. Especially if the laser tape measure will be used, for example, for precise fitting of furniture parts or installation of plumbing junctions, where every millimeter is always taken into account.

The smaller the error, the better. Devices whose deviations do not exceed 1÷1.5 mm are highly accurate. Most of the most affordable laser tape measures have an error of up to 3 mm. But if this range is larger, then the device can no longer be called particularly accurate, and you should think about whether you need such measurements with such significant errors. .

Most rangefinders in an affordable price range are equipped with second-class lasers with a red glow. Color does not in any way affect the accuracy of measurements, but in bright light the point becomes barely noticeable. In addition, direct contact with the eye close at a distance such a beam can cause a burn to the cornea.

The green beam from a first class laser does not pose such a danger, and is more noticeable even in bright sunshine. True, rangefinders with such a laser are still rare and are much more expensive.

It is definitely worth evaluating the body of the device. It has already been said that the security class must be at least IP44, and the higher this indicator, the better. This will allow you to work in conditions of heavy dust and in the rain. Elastic lining will help protect the rangefinder if it is suddenly dropped from your hand. Devices in a shock-resistant case do not lose their functionality when dropped onto a hard base from a height of one to two meters.

But, of course, it’s better not to drop it. For this purpose, many models are equipped with special straps, clips for carrying in a pocket, and belt pouches.

An important quality of any device used in construction is its operating temperature range. That is, it should function equally well both at the peak of summer heat and in frosty winter weather. This parameter must be indicated in the technical data sheet of the product.

Ideally, the rangefinder should be convenient to work in cold weather without removing seals or gloves, that is, the control buttons should be quite large. There is one more nuance - rubber buttons can become stiff in the cold and lose elasticity. So it makes more sense to purchase a rangefinder with silicone buttons for such purposes.

When working in the cold season, fogging of the optics becomes a “scourge”. Therefore, you should choose a rangefinder that uses lenses that eliminate this drawback.

The rangefinder should be convenient for the owner. You should evaluate how it “fits in your hand” and how convenient it will be to press the start button in difficult positions.

It is difficult to say whether the excessive compactness and low weight of the device is an advantage. Sometimes it happens that it's too miniaturized and a lightweight laser rangefinder, on the contrary, complicates measurements, since it reacts sensitively to even very slight trembling of the hand. Of course, there must be a reasonable measure in everything - a device that is too large and heavy will also be extremely inconvenient.

If you plan to carry out a large number of measurements from one “base” point, then you should choose a device that has the ability to be fixedly mounted on a rotating tripod.

It would be useful to immediately clarify which batteries and in what quantities ensure the operation of the device. Sometimes the duration of operation on a set of batteries is also indicated. If the laser rangefinder is powered by a built-in battery, then the kit must include an appropriate adapter for charging from the mains.

To preserve the potential of power supplies for as long as possible, many laser rangefinders are equipped with an automatic shutdown function when not in use. For example, if no measurements have been taken for a minute, the power will be turned off. The duration of the pause can be different, and often you can set it yourself in the preliminary settings.

It is convenient if the device screen has an indicator of the power supply charge level.

The simplest rangefinders are designed only to measure distances from one reference point, which in most cases is the rear end of the body. That is, the device is applied to the surface from which it is necessary to take measurements, and then the start button is pressed.

More advanced rangefinders provide the ability to take measurements from several reference points of your choice. For example, four points: from the rear or front end sides, from the point of attachment of the device to the tripod, from the tilted or extended support. By the way, in some models, when this stop is opened, switching to the desired measurement mode occurs automatically.

Modern laser rangefinders represent a whole “computational complex” that allows not only to determine distances, but based on these values also to carry out a number of necessary calculations:

— For such a device it will not be difficult to quickly and accurately display the area and volume of a room. Moreover, areas can often be calculated for figures located on a slope (for example, roof slopes).

— The built-in “Pythagoras” function makes it possible to determine the length of the side of a triangle, which is impossible or extremely difficult to measure in the usual way. For example, you can determine the height of an object by measuring the distance to its base and top point. Or, say, calculate the required distance to an object if direct visibility to it is limited by some temporary or permanent obstacle.

A built-in calculator with included calculation programs allows you to quickly determine those quantities that are currently impossible or extremely inconvenient to measure. For example, the Pythagoras function calculates the unknown side of a triangle from two measured ones.

— A convenient function is to divide the distance into a given number of segments of equal or equal proportions to the length. For example, this will make it easier to accurately position fence or foundation posts, guide sheathing, etc.

— The discrete ranging (tracking) function will be a good help. This means that the rangefinder will take measurements at certain small intervals as the direction of the laser beam moves. It becomes possible, for example, to find the distance to an outer or inner corner, when it is not possible or very difficult to “aim” accurately. The display will optionally show the minimum or maximum value of all those obtained during such “probing” of the object.

— Measured readings and calculated values can be entered into the rangefinder’s internal memory cells or recorded on an SD card. You can purchase a device that will automatically transmit data via Bluetooth to a mobile device. Often a cable connection to computers is provided for the exchange of received information.

— Some devices also allow you to carry out angular measurements - for this they are equipped with an inclinometer function. That is, after placing the rangefinder on a tripod and checking its horizontality, you can accurately calculate the angular values of the heights of nearby objects. This will further expand the capabilities of the device for “field” work and when marking for finishing.

When choosing, you should evaluate the information content of the display and its clarity for quick perception. Don’t be too lazy to immediately check how clearly the operating instructions are written, so that you don’t have to look for answers on the Internet or master working with the device “empirically”, that is, by the “trial and error” method.
The disadvantage of some models is that the readings are very difficult to read or become completely invisible in clear sunny weather or at dusk. Therefore, it is preferable for such operating conditions to have a rangefinder with a backlit screen.
The completeness has already been mentioned above. But we still need to add a couple more points.

— The accuracy of measurements often depends on the state of the surface of the object to which the range is determined. Thus, it may have too high an absorbing or scattering ability, making it difficult to reflect the beam. Or, conversely, a mirror-polished surface can make its own “adjustments.” So that you don’t have to come up with anything along the way, it’s better to have a standard target. It is usually double-sided, with thoughtful contrasting colors on the sides. When measuring at short distances (up to 40 meters), a light target is often used, and vice versa.

— And to make the trace of the laser beam more visible in unfavorable conditions, glasses with a special light filter are often included in the kit. If they are not included in the kit, you can purchase them separately - they are not that expensive.

Finally, one of the important selection criteria is always the brand of the product. Preference, of course, should be given to proven brands that enjoy unquestioned authority in this area. These include devices from Leica, Bosch, DeWalt, Makita, and AEG. Excellent rangefinders at a fairly reasonable price are offered by Condtrol, ADA, Hammer, ADA, RGK, STABILA, and Skill. Interestingly, Chinese products from various companies also show very good results. But they, as a rule, have a common problem, which is the almost complete absence of warranty obligations and the possibility service. That is, they serve regularly for who knows how long (depending on your luck), and then it is better to replace them - fortunately, the price is low.

By the way, if you choose a “branded” product, then it makes sense to immediately check in the store both the terms of the warranty and the availability of branded service centers in the immediate vicinity.

Now let’s take a short “excursion” into the models of laser rangefinders that won the greatest appreciation from users in 2017.

Brief overview of the top models of laser rangefinders (2017)

To avoid confusion, we will divide the rating models into two subcategories. The first of them is rangefinders, mainly intended for indoor work, that is, with relatively small measured distances. In the second - devices that allow successful do work on the ground.

Laser rangefinders for work indoors or at short distances

"BOSCH DLE 40"

One of the undisputed leaders in popularity among devices of this class.

“Bosch DLE 40” - the model is in extremely high demand among a wide range of consumers

Basic device characteristics:

— Laser class - 2;

— Wavelength - 635 nm;

40 m.

- Amount of pointscountdown- two.

— from -10 to +50 degrees.

— Measurement time- 0.5 s.

— Batteries - 4 batteriesAAA.

— Dimensions - 100×58×32 mm.

— Weight - 180 g.

volume, calculations triangles

— Approximate cost - 6200 rubles.

— Highest reliability in any operating conditions.

— Economical consumption of food.

— Comfortable body with elastic linings that won’t slip even from wet hands.

Flaws:

— In bright sunlight, the display readings are not particularly visible. Additional lighting would be nice.

— This particular model does not have a bubble level.

"Makita LD030 P"

Compact laser rangefinder with a limited number of functions and low cost

Device characteristics:

— Laser class - 2;

— Wavelength - 635 nm;

— Maximum measurement range - up to30 m.

— Measurement accuracy - ± 1.5 mm.

- Amount of pointscountdown- two.

— Operating temperature range -from - 25 to +50 degrees.

— There is no threaded socket for a tripod.

— Batteries - 2 AAA batteries, which should be enough for 5000 measurements.

— Dimensions - 115×53×25 mm.

— Weight - 90 g.

— Set of functions: single range measurements, area calculations, tracking (discrete measurements)

— Included is a convenient belt pouch.

— Approximate cost - 4100 rubles.

Noted advantages:

— Convenient layout for operation.

— No “overload” with control buttons, simple operation algorithm.

— Large symbols on the display and good backlighting – readings are easy to take, including in sunny weather or in poor visibility conditions, and by people with low vision

- Affordable price.

Comments made:

Unfortunately, with such a “loud” brand, there is a very high percentage of complaints, apparently due to licensed assembly. Warranty obligations are strictly observed, but nevertheless...

Makita laser rangefinder prices

Makita laser rangefinder

"Control X2 Plus"

Multifunctional laser rangefinder in the mid-price range

Basic model characteristics:

— Laser class - 2;

— Wavelength - 650 nm;

— Maximum measurement range - up to60 m.

- Amount of pointscountdown- three, taking into account the folding bracket for measuring from corners.

— Measurement systems - metric and inch.

— Dimensions - 110×43×26 mm.

— Weight - 70 g.

— A set of functions for calculating area,volume, calculations triangles, segmentation, tracking.

— Included is a cover.

— Approximate cost - 4400 rubles.

The indicated advantages:

— Good functionality;

- Quite affordable price.

— Original appearance and easy-to-read display.

Claims made:

— The device is too “heat-loving” - even with a slight frost, malfunctions begin.

— The downward sloping body makes it difficult to maintain a stable vertical position of the rangefinder when measuring the distance from the top.

The buttons are located too close, and when working with mittens this creates considerable difficulties.

— The speed of measurements leaves much to be desired - you have to wait more than a second to get the result.

"ADA Cosmo MINI A00410"

Reliable and accurate laser rangefinder at short distances.

Laser rangefinder characteristics:

— Laser class - 2;

— Wavelength - 650 nm;

— Maximum measurement range - up to30 m.

— Measurement accuracy - ± 3 mm.

- Amount of pointscountdown- two;

— Temperature range of operation - from 0 to +40 degrees.

— Batteries - 2 AAA batteries.

— Dimensions - 107×428×24 mm.

— Weight - 110 g.

— A set of functions for calculating area,volume, calculationstriangles, tracking.

Advantages of the model:

— A good, but not redundant set of functions.

— Compact dimensions, impact-resistant housing with protection class IP54.

— A very simple and convenient operating algorithm. Just three buttons.

- Easy to read display.

— Well visible laser beam.

— Super attractive price for similar functionality

Flaws:

- Not the most outstanding accuracy indicators - an error of 3 mm sometimes becomes too much.

— Not designed for negative temperatures.

— No cover included.

— There are complaints about the clarity of the operating instructions supplied with the rangefinder.

"RGK D30"

An easy-to-use laser roulette with a minimum set of necessary functions and a high user rating.

Model characteristics:

— Laser class - 2;

— Wavelength - 6390 nm;

— Maximum measurement range - up to30 m.

— Measurement accuracy - ± 2 mm.

- Amount of pointscountdown- one.

— Operating temperature range is from 0 to +40 degrees.

— Measurement systems - metric and inch.

— Measurement time- from 0.5 to 4 s.

— Batteries - 2 AAA batteries.

— Dimensions - 110×43×24 mm.

— Weight - 69 g.

— A set of functions for calculating area,volume, calculationstriangles, tracking

— Includes a case and a wrist strap.

— Approximate cost - 2500 rubles.

Advantages mentioned by users:

— Excellent housing protection – IP54.

— Soft silicone buttons.

— 10 memory cells for storing measurement and calculation results.

— Automatic shutdown function when idle.

— Backlit display, easy to read in any conditions.

Flaws:

— The bubble level on the body is more of a decorative element, since it does not differ in accuracy.

— The error when measuring at the same point with a stationary device, although not much, still went beyond the stated ± 2 mm

- Not particularly good performance.

— You cannot work at subzero temperatures.

These disadvantages are largely compensated by the simplicity of the device and a very affordable price.

Laser rangefinders for field work

Such devices have fairly high measured ranges and are often equipped with optical sights or video cameras. They allow you to carry out a variety of operations on marking the site, linking objects, and performing construction work.

"BOSCH GLM 250VF"

High-quality “all-weather” model with a wide range of functions

The model is far from new, but every year it consistently ranks among the most popular and reliable.

Basic device characteristics:

— Laser class - 2;

— Wavelength - 635 nm;

— Maximum measurement range - up to250 m.

- Amount of pointscountdown- four, including a folding pin for measuring from hard-to-reach places.

— Operating temperature range -from - 10 to +50 degrees.

— Measurement systems - metric and inch.

— Measurement time- 0.5 s.

— Threaded socket for a tripod ¼ inch.

— Built-in optical sight

— Dimensions - 120×66×37 mm.

— Weight - 240 g.

— A full set of functions for auxiliary calculations.

— Included is a carrying strap.

- Approximate cost - 22000 rub.

Advantages mentioned by users:

— Excellent performance in any measurement conditions.

— 20 memory cells for storing measurement and calculation results.

— Automatic shutdown when idle.

— Availability of a convenient optical “sight” for measuring distances to distant objects.

- Highest build quality.

Flaws:

— There is no battery charge indicator.

— In dusty conditions and on a bright sunny day, the measurement range drops to about 100 meters.

— Despite the emergence of new models, apparently due to the remaining high demand, the price is quite high and does not yet have a downward trend.

Prices for BOSCH laser rangefinder

BOSCH laser rangefinder

"LEICA DISTO D510"

Professional model with high measurement accuracy.

Basic device characteristics:

— Laser class - 2;

— Wavelength - 635 nm;

— Maximum measurement range - up to200 m.

— Measurement accuracy - ± 1.0 mm.

- Amount of pointscountdown- five.

— Built-in video viewer with 4 multiple zoom;

— A tilt sensor with a range of 360 degrees allows for angular measurements. Units of measurement – degrees, percent, mm/m, inches by feet.

— Operating temperature range -from - 10 to +50 degrees.

— Measurement time - 0.5 s.

— Threaded socket for a tripod ¼ inch.

— Batteries - 2 AAA batteries.

— Dimensions - 143×58×29 mm.

— Weight - 198 g.

- Full set.

— Communication system with mobile devices via Bluetooth protocol.

— Built-in memory for 30 cells. Possibility of installing an additional memory card.

— The set includes a convenient belt pouch-holster and a wrist belt.

— Approximate cost - 38,500 rubles.

Advantages mentioned by users:

— Highest reliability and accuracy in any operating conditions.

— A very wide range of functions, a very convenient interface for working with them.

— Impeccable production quality.

— The device is included in the State Register of Measurement Systems.

Flaws:

— High price, making the device inaccessible.

— Batteries run out quickly, even when the device is turned off. When left for a long time, it is better to remove the batteries from the compartment.

"CST/Berger RF25"

Professional grade laser rangefinder. Natural glass coated optics and an original ceramic lens fixation system determine the highest measurement accuracy.

Device characteristics:

— Laser class - 2;

— Wavelength - 635 nm;

— Maximum measurement range - up to250 m.

— Measurement accuracy - ± 1.0 mm.

- Amount of pointscountdown- four .

— Three-position stop pin on the rear of the housing.

— Built-in sight and additional connection of a full-fledged optical “sight” for working at extreme distances.

— Length measurement systems - metric and inch.

— Operating temperature range -from - 10 to +50 degrees.

— Measurement time - 0.5 s.

— Threaded socket for a tripod ¼ inch.

— Precise bubble level on the body.

— Batteries - 4 AAA batteries.

— Dimensions - 120×66×37 mm.

— Weight - 240 g.

- Full setnecessary functions for “field” calculations.

— Built-in memory for 30 cells.

— Includes a convenient protective case and a wrist strap.

— Approximate cost - depending on the configuration and the region of sales - from 19 to 25 thousand rubles.

Advantages of the model:

— unquestionable measurement accuracy at any distance thanks to high-quality optics.

— Wide range of functions.

— Multi-line informative display with easy to read readings.

— Excellent build quality.

— Impact-resistant housing with a degree of protection IP54. The device can easily withstand falls onto a concrete floor from a height of 1 meter.

— There is no data recorded on model returns due to lack of quality.

Flaws:

There were no significant shortcomings expressed by users, with the exception of the inflated price (taking into account the lack of a slope sensor).

So, the criteria for choosing a laser rangefinder were considered, and an overview of popular models was given. In conclusion, it is worth saying, perhaps a banality, but it is still necessary.

Tools of this class should be purchased exclusively in reliable specialized stores, where you can get competent advice, study the terms of the guarantee, and be sure to make a note in your passport about the place and date of purchase. Trusting dubious retail outlets or paying a lot of money for a “pig in a poke” when buying online from random sellers is hardly wise.

Prices for popular laser rangefinders

In conclusion, an interesting video showing the capabilities of the Bosch GLM 50 C laser rangefinder

Video: Demonstration of the functionality of the Bosch GLM 50 C laser rangefinder

Ministry of Education and Science of the Russian Federation

Federal state budget educational

Institution of higher professional education

"Tula State University"

Faculty of Automatic Control Systems

Department of Control Devices

Test and coursework in the discipline

“Physical and theoretical foundations for constructing instruments and

control and navigation systems"

on the topic “Laser rangefinders”

Completed by: student gr. 130801

Volynkin P.N.

Checked by: Likhosherst V.V.

Introduction……………………………………………………………………...3 pages

1. Advantages of a laser rangefinder………………..…………………..4 page

2. Design and principle of operation………………………………………….. 5 pages

4. Example of a laser range finder…………………………………………....6 page

5. History of development.................................................. ...........................................7 page

Conclusion................................................. ........................................................ ....9 pages

Introduction

Laser rangefinder is a device for measuring distances using a laser beam.

Widely used in engineering geodesy, topographical surveys, military affairs, navigation, astronomical research, and photography. Modern laser rangefinders are in most cases compact and allow you to determine distances to objects of interest in the shortest possible time and with great accuracy.

Laser rangefinders differ in operating principle: pulse and phase.

A pulsed laser rangefinder is a device consisting of a pulsed laser and a radiation detector. By measuring the time it takes the beam to travel to the reflector and back and knowing the speed of light, you can calculate the distance between the laser and the reflecting object.

A phase laser rangefinder is a rangefinder whose operating principle is based on the method of comparing the phases of the sent and reflected signals. Phase rangefinders have higher measurement accuracy compared to pulse rangefinders. Phase rangefinders are also cheaper to manufacture. It is phase rangefinders that have become widespread in everyday life.

Advantages of a laser rangefinder

Firstly, you can measure distances alone; you just need to point the device at the target and press a button. This lightweight and compact instrument is convenient and easy to use, and allows you to accurately measure not only the length, but also the width and height of objects, calculate volumes and areas, and also perform arithmetic calculations. At the same time, the laser rangefinder allows you to save measurement results in its memory.

In addition, unlike traditional steel or fabric tape measures, laser rangefinders are practically not subject to wear over time - you just need to change the batteries on time. And, of course, the undeniable advantages of laser rangefinders are high measurement accuracy, speed of operation, ease of operation and reliable protection from dust and moisture. If you drop the rangefinder in the mud, quickly and carefully rinse it under running water and continue working. Some models of laser tape measures are equipped with an inclinometer, which allows you to measure the height of an object in one step - that is, the hypotenuse and angle are measured, and the height is calculated automatically.

Design and operating principle

The pulse ranging method uses the following ratio:

Where L is the distance to the object,

C – speed of radiation propagation,

T is the time it takes for the impulse to travel to the target and back.

The task of determining the distance between the rangefinder and the target comes down to measuring the corresponding time interval between the probing signal and the signal reflected from the target. There are three methods for measuring range depending on the type of modulation of laser radiation used in the rangefinder: pulse, phase or pulse phase.

The essence of the pulse ranging method is that a probing pulse is sent to the object, which also starts a time counter in the range finder. When the pulse reflected by the object reaches the rangefinder, it stops the counter. Based on the time interval (delay of the reflected pulse), the distance to the object is determined.

With the phase ranging method, laser radiation is modulated according to a sinusoidal law using a modulator (an electro-optical crystal that changes its parameters under the influence of an electrical signal). Typically a sinusoidal signal with a frequency of 10...150 MHz (measuring frequency) is used. The reflected radiation enters the receiving optics and photodetector, where the modulating signal is released. Depending on the distance to the object, the phase of the reflected signal changes relative to the phase of the signal in the modulator. By measuring the phase difference, the distance to the object is determined.