Measurement range
The range at which the device remains fully operational without the use of additional receivers (see below); in other words, the radius of its action without auxiliary devices.
In some models, a range may be specified that shows the minimum (
3 cm,
5 cm) and maximum measurement ranges. But in most cases, only the maximum value is indicated.
The specific meaning of this parameter is determined by the type of instrument (see above). So, for optical levels, the measurement range is the greatest distance at which the operator can normally see the divisions of a standard leveling staff. For laser levels, this parameter determines the distance from the device to the surface on which the mark is projected, at which this projection will be easily visible to the naked eye; and in rangefinders we are talking about the greatest distance that can be measured. Typically, the measurement range is indicated for ideal conditions - in particular, in the absence of impurities in the air; in practice, it may be less due to dust, fog, or vice versa, bright sunlight "overlapping" the mark. At the same time, tools of the same type can be compared according to this characteristic.
Note that it is worth choosing a device according to the range of action, taking into account the features of the tasks that are planned to be solved with its help: after all, a large measurement range usually significa
...ntly affects the dimensions, weight, power consumption and price, but it is far from always required. For example, it hardly makes sense to look for a powerful laser level at 30-40 m if you need a device for finishing work in standard apartments.Accuracy
Measuring accuracy provided by a laser distance meter (see "Type")
This parameter is traditionally indicated by the error - the maximum deviation of the obtained results from the actual values, which may occur due to the imperfection of the device. The physical features of laser rangefinders are such that in such devices the error is practically independent of the measured distance. Therefore, the accuracy of such rangefinders is indicated in millimeters. At the same time, in our time, models are generally considered to be high-
precision, where this indicator does not exceed 1.5 mm (in some models it is only 1 mm); but even in relatively simple and inexpensive devices, deviations of more than 3 mm are practically not encountered.
The general selection rules for this indicator are traditional: the more accurate the device, the more expensive it is, as a rule. In addition, we emphasize that for everyday and even many professional tasks, the difference described above is not fundamental in accuracy. Therefore, it makes sense to specifically look for a rangefinder with a minimum error in the case when the measurement accuracy “to the millimeter” is fundamental. At the same time, it should be borne in mind that for such measurements, appropriate accuracy in the placement and use of the device itself will be required - otherwise, all the advantages will be nullified by errors from incorrect installation and operation.
Operating temperature
The temperature range at which the device is guaranteed to work for a sufficiently long time without failures, breakdowns and exceeding the measurement error specified in the characteristics. Note that we are talking primarily about the temperature of the device case, and it depends not only on the ambient temperature — for example, a tool left in the sun can overheat even in fairly cool weather.
In general, you should pay attention to this parameter when you are looking for a model for working outdoors, in unheated rooms and other places with conditions that are significantly different from indoor ones; in the first case, it makes sense to also make sure that there is dust and water protection (see "Protection class"). On the other hand, even relatively simple and "myopic" levels / rangefinders usually tolerate both heat and cold quite well.
Auto power off
The time after which the device turns off by itself completely if the user does not perform any action.
See above for more information on auto power off; and his time has a double meaning. On the one hand, if this time is short, then the idle time of the device will be minimal, which helps to save energy. On the other hand, too frequent auto-shutdown (with subsequent switching on for work) is also undesirable — it increases the wear of components and reduces the resource, and it is not always convenient for the user. So manufacturers choose the time, taking into account the balance between these moments, as well as the general class and purpose of the device. So, in some rangefinders, this indicator does not even reach a minute, although in most such devices it is in the range from 3 to 8 minutes; and in some professional devices (primarily levels), the auto-off time can be 30 minutes or more (up to 3 hours).
Laser auto-off
takes no action.
This parameter is relevant primarily for laser rangefinders. This is due to the fact that in such devices the laser is one of the most “gluttonous” (in terms of power consumption) components, moreover, it is used only directly in the measurement process. Therefore, along with auto-shutdown of the device itself (see above), such devices can also provide auto-shutdown of the laser — mainly as a “safety” function in case the user himself forgets to turn off the emitter. The time of such an auto-shutdown usually does not exceed a minute — one and a half, although there are exceptions.
Diode emission
The wavelength of the radiation emitted by the LED of the level or rangefinder; this parameter determines primarily the colour of the laser beam. The most widespread in modern models are LEDs with a wavelength of about 635 nm — at a relatively low cost, they provide bright red radiation, giving a well-visible projection. There are also green lasers, usually at 532 nm — the marks from them are even better visible, but such LEDs are quite expensive and rarely used. And radiation with a wave longer than 780 nm belongs to the infrared spectrum. Such a laser is invisible to the naked eye and is poorly suited for leveling, but it can be used in rangefinders — of course, with a viewfinder (see "Type" for more details).
Display
Own screen on the device body.
All
displays are used to display various additional information, which makes control more convenient and clear compared to
models without displays ; but the specific functionality and features of the screen may vary, depending on the type. There are black and white options,
backlit displays,
color and even
touch screens. More details about each:
— B/W without backlight. The simplest and most inexpensive type of display: a black-and-white LCD sensor without its own backlight. Despite their overall simplicity, such screens can have quite extensive capabilities: technically, they can display data related to the operation of the device (for example, the results of rangefinder measurements), and other additional information, including quite specific ones. In fact, the only thing that b/w displays are not suitable for is displaying images from a digital camera. In practice, the functionality of the display is selected according to the capabilities of a particular device. As for the lack of backlighting, this feature makes it difficult to use in low light conditions, but it reduces the price and power consumption. In addition, under the sun or other bright lighting on advanced backlit screens the image may “fade”, while on the simplest black and white screens wi
...thout backlight it, on the contrary, becomes even clearer.
— B/W with backlight. Black and white screens equipped with backlight systems. Note that this category actually includes two types of displays: traditional black-and-white LCD matrices in the “black image on a white background” format, supplemented by an external lighting system, as well as single-color screens in the “light image on a black background” format, where the light itself can glow. image. Be that as it may, such displays can be used without restrictions in low light, but the downside of this is increased power consumption - especially in models where the backlight is constantly on.
- Colored. The functionality of color displays can be different - from the simplest LCD screens, capable of displaying only a few primary colors (for example, highlighting the most important numbers on the screen in a different color), to full-color matrices (like tech used, for example, in laptops). The first type is somewhat more convenient and clearer than the b/w displays described above, costs a little more, but has no other differences. The most advanced color screens, in turn, can even display a picture from a digital camera - and, in fact, they are mainly used in devices equipped with such cameras.
- Touch. The most advanced type of display. Such screens are almost always made in color and equipped with backlighting, and touch controls also allow them to be used to control the device (similar to what happens in smartphones and tablets). In terms of control, touch screens are more convenient and intuitive than traditional panels with buttons, switches, etc.; they are much better suited to handle the abundance of functions, and also provide some additional capabilities that are not available with traditional controls. On the other hand, such equipment is not cheap, and it simply does not make sense to use it in relatively simple and inexpensive devices - for such models, more affordable displays, even the simplest black and white ones, are quite sufficient. Therefore, the presence of a touch screen is almost guaranteed to be a sign of a high-end device with an abundance of functions.Spirit level
Level based on a spirit capsule (or several such capsules) built into the body of the instrument.
Such a device allows you to control the position of the device — namely, to check whether it is set horizontally; however, some models also provide levels for the vertical position, and sometimes even for tilting at 45 ° or another angle. But the specific purpose
of the spirit level may be different, depending on the type and general level of the device. The most popular option is a preliminary, rough installation of the laser level in the horizontal: the initial adjustment is carried out manually using a level, and after that the built-in self-leveling mechanism is activated. In simple and inexpensive household levels where high accuracy is not required, the spirit chamber may even be the only way to set it to the desired position; and some of these devices can also be used as full-fledged building levels.
Bluetooth
The presence
of a Bluetooth module allows you to broadcast the measurements to the connected device. Thus, you can make the device as compact as possible, and read the received data directly from the phone. And in the era of high technology and the ability to control the phone with any device, such a decision looks quite reasonable.