Just a few years ago, people could only dream of distinguishing between objects and objects in the dark. Until now, this opportunity has been exclusively in animals and birds. Since the development of technological progress and the military industry as a whole, this problem has been solved by creating special equipment and devices for working at night. So the night vision sight was created. What is he like? And how to choose it for yourself?
General Description of Night Vision Sights
Night vision sights are small-sized devices that look like monoculars. They are usually installed on mobile equipment, such as weapons, in order to facilitate targeted shooting in the dark.
Despite the fact that such products have a simple appearance, inside they are more complex. So, night vision sights for hunting consist of the following working elements:
- a lens;
- IR illuminator (with infrared radiation);
- batteries;
- electron-optical converter (image intensifier tube);
- body and eyepiece.
The night vision sight is an optical device used to conduct aimed fire from small arms at night. These devices can be either completely night-time or have a dual purpose (used both day and night) and even triple purpose (used during the day, at dusk and at night). Also, such equipment can be presented in the form of nozzles for a standard telescopic sight.
The device itself is usually mounted directly on top of the weapon in accordance with the axis of the barrel. Use this sight during a defensive battle, to protect objects around the perimeter, in the case of sniper fire from shelter.
What is the principle of the device for working in the dark?
The principle of operation of the device for night vision, or in short NVD, is to capture the light reflected from the object and increase it many times. In this case, a light pole, a fluorescent lamp, a starry sky or a full moon can act as a light source.
The process of the device’s operation is as follows: the light reflected from the light source is transmitted to the sight lens, and then immediately redirected to the converter (image intensifier tube); at the next stage, there is a multiple increase in the light received by the device and its transmission to the eye of the observer.
As a result, the light signal transmitted to the night vision sight is processed in a certain sense and acquires a monochrome look. Typically, the observer sees the resulting image in green tones.
If a person with a night vision device is forced to work in conditions of complete absence of light, then he can always use the infrared lamp built into the device . Recall that such lamps emit light recognized by the eye of the observer in the long wavelength range.
What types of night vision devices are there?
If you are just planning to purchase a night vision scope, you need to know what types of NVD are. In total, these products can be divided into three types:
- instruments used to observe objects in the dark;
- sights for hunting and military weapons;
- glasses for night vision.
All these types of NVD (except the first) can be used both as independent products, and in combination with weapons. Also on sale there are light amplifying and thermal imaging devices for night vision. Therefore, the choice of device will directly depend on the ultimate goals of using the equipment and on the distance at which it is planned to come into direct contact with the enemy or object of observation.
What are night surveillance devices for?
Most night observation devices are equivalent in their operation principle to binoculars and periscopes. They are used in reconnaissance operations, in the case of orientation on the ground. However, they are almost not used to carry out aimed fire.
Glasses for night vision: what are they?
Glasses, in contrast to the sight, are placed at eye level of the observer. They are attached to the helmet using special straps, thereby freeing up the hands. If you plan to use glasses with small arms, you must additionally purchase a special sighting device, in the role of which an infrared laser is usually used.
What is the difference between the models of sights?
All models of sights may differ from each other depending on the manufacturer and the purpose of the device. For example, they can have various electron-optical converters. In particular, the difference lies in the characteristics, for example, resolution and sensitivity of the cathode, as well as in the frequency of the field of view.
In addition, the night vision scope can be optical and digital. At the same time, digital devices that look more massive than optical ones are characterized by the presence of a range finder, a high detection range, more than three types of sighting settings, and an aiming mark. Optical are compact sights with a small magnification that can be endowed with additional digital twilight illumination, as well as a gyroscopic automated system for switching off and on the backlight.
Accordingly, the cost will depend on the type of sight, the manufacturer and the functionality of the product.
What characteristics should I look for?
When choosing a digital night vision scope for yourself, pay attention to such an important option as signal / noise (S / N). This value will allow you to observe the intended object in poor light conditions and without image distortion. In the most modern models, this value is set on a scale from 3.5 to 36. Ideally, models should be selected for which this indicator is not less than 20.
The second important point when choosing a scope is resolution. As a rule, it is indicated in the number of pairs per millimeter (lp / mm), and the contrast and frequency of the transmitted image depends on it. For example, a high-quality picture is capable of transmitting a digital night vision scope with a resolution of 30 to 70 lp / mm.
The third important indicator is the level of photosensitivity, measured in hA / lm. This characteristic determines the specific dependence of the numerical parameters set in the device on the real exposure.
It is also worth remembering that night vision optical sights may vary depending on the type of functioning image intensifier tube. They are I and I +, II and II +, as well as III generations.
Night devices with image intensifiers of I and I + generations
Products with I generation I / O are relatively inexpensive. Such devices include, for example, hunting rifles. In addition, the first generation night-time devices are designed to shoot at a target from a short distance (up to 80-150 m). They are characterized by the following features:
- the presence of clarity in the image exclusively in the center;
- image distortion at the edges;
- the presence of a small permit.
A striking example of such products is the night vision scope "Daedalus" 180 HR (100). This model is equipped with a durable ceramic-metal body and is perfect for working with a smoothbore gun.
From the advantages of this class, we can distinguish its affordable price. Of the minuses - sensitivity to flare and limitation of additional options.
Generation I + equipment has a high resolution. It is considered more powerful and has reliable fiber optic washers that stand at the input and output of the device. And although such models, as a rule, have a higher price than the first generation image intensifier tubes, they are equipped with special protection against flare. For example, such devices include Pulsar (night vision scope).
Night devices with image intensifier II and II + generation
Second-generation devices are considered a kind of middle ground among other devices in the product line. That is why they are most in demand among amateur hunters with a certain experience in target shooting. The main advantage of such equipment is that with its help you can perform work even in the complete absence of any kind of lighting.
Also, these devices have modern high-aperture filters that contribute to a three- and five-fold increase in the studied object. In addition, night devices of this generation are able to distinguish the human silhouette in fine details from a distance of 250-300 m.
Generation II + devices have a useful option to increase the light emission capabilities. As practice shows, devices of this type have greater sensitivity and high resolution images, so they are often used when working in the open. For example, Sentinel night vision scope and its models G2 + 3x50, G2 + 3x50 MD and others can be attributed to such devices.
Generation III night vision devices
Third generation night vision sights are professional devices. They have a number of auxiliary options that help to convey the clarity of the image taking into account the color scheme and shades. Devices of this type are not suitable for work in cities; therefore, they are widely used in certain rescue operations in open areas. A striking example of companies producing such devices is Yukon. The night vision sight in its execution has excellent quality and has high performance characteristics.
What to consider when choosing a sight?
When choosing a scope for night vision, it is necessary to take into account such nuances as the clarity of the transmitted image. And of course, the clearer the observation object is displayed on the screen, the easier it will be to identify it. The second thing to pay attention to is the brightness level of the picture. The third important point is to assess the strength and durability of the equipment.
Next, pay attention to the possibility of approximating the image in the process of working with the device. For example, it can be a three- or four-fold increase. Also look at indicators such as lens diameter, field of view and viewing angle, focus, weight and dimensions. In addition, read, choosing a night vision scope, reviews. So, for example, many beginners like the sights of the first generation. Experienced shooters and observers prefer equipment of generation II, II + and III.
In addition, coming to your favorite model of sight, take an interest in the characteristics and features of the device. In particular, many sights are suitable exclusively for a certain brand of weapons.
Also, if you want to actually test the real capabilities of the device, you can always use the service that is popular today - a test drive. Thanks to her, you can choose 2-3 models of sights and conduct their testing for two weeks.
In conclusion, we say that, choosing a sight, you need to consider the objectives of its acquisition, terrain features and other nuances.