What is the difference between infrared night vision and digital night vision?
In the development of night observation equipment tools, night vision devices have always played an important role. From the early military warfare to the current military equipment, night vision goggles have helped night observers solve the most basic viewing needs. From the early infrared night vision devices to the new digital night vision devices, night vision products have been constantly updated and improved, and their functions are becoming more and more important. Although infrared night vision devices and digital night vision devices are "brothers of the same root" in the night vision family, there is a big difference in "character" between the two. Let's take a look at the difference between the two brothers.
Before detailing the difference between the two types of night vision devices, let us first look at the imaging renderings of the two types of night vision devices.
What is the difference between infrared night vision and digital night vision?
The above two pictures are the imaging effects of the infrared night vision device and the digital night vision device in the night environment. It can be seen from the figure that most of the images of infrared night vision devices are green images, and the shape of the images is circular; most of the images of digital night vision devices are black and white images, and the images are rectangular. In fact, no matter what color imaging effect, the ultimate goal of the night vision device is to be able to clearly find the target in the dark or low-light environment at night, as the so-called "third eye in the dark night, let you see what you have never seen". From this point of view, the two "reach the same goal by different routes".
The difference between infrared night vision device and digital night vision device is as follows:
1. Working principle
1. Working principle of infrared night vision device
The principle of the infrared night vision device is to collect and intensify the existing light by focusing the light on the image intensifier through the eyepiece. Inside the intensifier, a photocathode will be "activated" by light and convert photon energy into electrons. These electrons pass through An electrostatic field inside the intensifier is accelerated and hits the phosphor surface screen (like a green TV screen), creating an image visible to the human eye. To put it simply, the principle of the night vision device is to convert the invisible light (twilight or infrared light) signal from the target into an electrical signal, then amplify the electrical signal, and convert the electrical signal into a light signal visible to the human eye.
2. Working principle of digital night vision device
Digital night vision device is also known as digital night vision device, and its English name is Digital Night Vision. Most digital night vision devices use high-sensitivity CCD (CMOS) image sensors to process and convert the low-illuminance light into digital electrical signals, and then transmit them to the tiny liquid crystal display inside the night vision device.
It can be seen from the above description of the working principle that the core components of the infrared night vision device and the digital night vision device are different. The former uses an image intensifier (image intensifier tube), and the latter uses a CCD (CMOS) image sensor. It is the main difference between the two, and it is also the root cause of other differences.
2. Applicable environment
The infrared night vision device can only be used in dim light or total darkness (that is, at night). Due to the limitation of the imaging principle, it cannot be used normally in the daytime. Watching, but it is meaningless to use the infrared night vision device at this time, it is not as clear as the naked eye.
The digital night vision device is not restricted by the ambient light at all, and the use mode can be adjusted to day or night mode. It is an all-weather photoelectric instrument for both day and night. Color imaging during the day, black and white or green imaging at night.
3. Magnification
Since the magnification of the microlight tube of the infrared night vision device is about 0.5, the lens is not easy to achieve a large magnification, and generally has a fixed magnification, such as 1 times, 3 times, 5 times, etc.
The digital night vision device itself will also have a fixed magnification, but it will also have a digital zoom. For example, Alfa's new multi-functional third-generation digital night vision device DB550L itself has a magnification of 5 times, and the digital magnification is 1-4 times, which means that the overall magnification range of this digital night vision device is 5-20 times. In addition, the magnification of the digital night vision imaging system is similar to or greater than one, so generally speaking, with the same magnification lens, the magnification of the digital night vision device will be twice that of the infrared night vision device, such as an infrared night vision device with a magnification of 5 times. The lens of the vision instrument is 10 times higher than that of the digital night vision, which is very important.
4. Image resolution
Infrared night vision devices are divided into 1st generation +, 2nd generation +, quasi-3rd generation, 4th generation, etc. because of the different levels of the image intensifier tubes. The resolutions of different levels of night vision devices are different. For example, the resolution of most 2nd generation + night vision devices in China is between 50-60 line pairs, and it is still a relatively high resolution. In terms of viewing distance, even if infrared is added, it is 100-200 meters. The effective distance of left and right. The ordinary CCD resolution of digital night vision devices is also above 50 line pairs. For example, the third-generation digital night vision devices use low-light high-definition CCD photoreceptors. The image brightness can be adjusted through the system, which can reach the second generation of infrared night vision devices + Levels like tube levels. It has good infrared sensing ability and can achieve an effective observation distance of more than 500 meters in total darkness.
5. Features
As a night vision tool used at night, the infrared night vision device's most basic and main function is night observation, and there are few other functions.
Digital night vision devices, especially the new third-generation digital night vision devices, can not only take high-definition photos and videos, but also HDMI high-definition video transmission, record time, date and sound, GPS positioning, electronic compass level, WIFI connection to mobile APP, etc., can It is said that the digital night vision device is a brand-new multifunctional night vision device. Formally due to the unique functional characteristics of digital night vision devices, it is more extensive than infrared night vision devices in terms of application scope and industry.
6. Standby time
Night vision devices are also electronic optical products that require batteries to work properly. Most infrared night vision devices use CR123A lithium batteries with stable performance, and the battery type is relatively simple, but the standby time is only about 4 hours. The digital night vision device also uses CR123A type lithium battery, and can also use AA type ordinary battery. Of course, it can also use power bank, vehicle power supply, DC power supply, the power supply mode is flexible, and the standby time is longer than the infrared night vision device. For example, if you use a 2000mAh power bank for the monocular ORPHA brand CS-6 monocular monocular digital night vision device, the standby time can last up to 20 hours.
7. Service life
The infrared night vision device uses the image intensifier tube as the core component, which is fragile. The service life of the first generation is about 1,000 hours, and that of the second generation is about 10,000 hours. The service life of the digital night vision device is relatively long, which is basically semi-permanent.
To sum up, infrared night vision is not as good as digital night vision? In fact, it is not entirely true, because infrared night vision devices were developed earlier and have many levels. In addition to civilian applications, high-end infrared night vision devices are also widely used in military and government departments. As a new product in the field of night vision, digital night vision devices are not as widely used in various industries as infrared night vision devices, but with the wings of technology, I believe digital night vision devices will fly farther!
