Digital night vision cameras and telescope thermal imagers are two important products for outdoor night vision equipment. Their day and night features have been recognized by more and more users. So what are the specific differences between the two types of instruments? From the working principle, category, effect and other aspects of the two types of instruments, the comparison will be explained one by one. I hope it will be of some help to you.
Use night vision equipment outdoors at night
1. Basic knowledge of night vision goggles
Before proceeding with these descriptions and comparisons, let's first understand the relevant knowledge of night vision goggles. At present, the mainstream products in the night vision market are divided into three types, one is the active night vision, also known as the tube night vision; the second is the passive night vision, also known as the thermal imager; the third This is a relatively new type of digital night vision. Whether it is a digital night vision camera or a thermal imager, they are designed to make it easier to observe or aim at the target in total darkness or low light.
Second, the working principle of digital night vision
Different from the traditional infrared night vision device, the digital night vision device does not use the image enhancement tube as the image intensifier, but uses the charge-coupled device (CCD) or complementary metal-oxide semiconductor (complementary metal-oxide) -semiconductor, CMOS for short) as an image intensifier. The low-illuminance CCD can recognize very dark light, and then convert it into a visible digital signal, which is displayed on the LCD screen inside the night vision device.
Three, the working principle of thermal imager
The thermal imager uses an infrared detector and an optical imaging objective to receive the infrared radiation energy distribution pattern of the measured target and reflect it on the photosensitive element of the infrared detector to obtain an infrared thermal image. This thermal image is related to the heat distribution on the surface of the object. Corresponding to the field. In layman's terms, a thermal imager is to convert the invisible infrared energy emitted by an object into a visible thermal image. The different colors on the top of the thermal image represent different temperatures of the measured object.
Fourth, the comparison of digital night vision and thermal imager
1. The ease of detecting the target
Detect and find the target at night. According to the different light conditions of the environment, the observation effect of the digital night vision device will be greatly affected. It is completely dark, in 1/2 month, 1/4 month, starlight and other environments, and the same digital night The distance of the target viewed by the visual instrument under the same setting will have a greater impact. On the contrary, thermal imagers are less affected by night light conditions. Thermal imagers convert the invisible infrared energy emitted by objects into visible thermal images and then display them on the display screen for observation. Therefore, from the perspective of the ease of detecting the target, the thermal imager is more likely to find the target.
2. The clarity of the image and the recognition of the target
There is no doubt that the thermal imager is easier to detect the target, but due to the display of its core component technology, the current higher resolution is just approaching the resolution of the mid-level digital night vision device. Digital night vision cameras use CCD and CMOS image sensors as image intensifiers. The technologies of CCD and CMOS have been very mature and have a wider range of applications, such as cameras, video recorders, and so on. Therefore, whether it is for viewing or taking photos and videos, the image clarity of the digital night vision is very high, and there is still a lot of room for improvement.
The picture on the left is the effect of the digital night vision, and the picture on the right is the effect of the thermal imager. From the two pictures, it can be clearly seen that the digital night vision has a higher degree of image clarity and recognition of the target person.
3. Function expansion function comparison
Due to the different working principles and core components, the extended functions of the two types of instruments have different characteristics. Regarding the video output function, the digital night vision device can output HDMI high-definition video, the thermal imager PAL/NTSC/AV and other video output, and the digital night vision device is more dominant in terms of the quality of the video output. As for other functions, the digital night vision device also has more extensions, such as GPS, electronic compass, WIFI mobile APP video transmission, etc., the digital night vision device will always be combined with the most advanced technology in advance and then the product will be upgraded. Because the technology of digital night vision is easier to combine with the technological achievements of other products to form a strong alliance.
4. Comparison of parameters
From the comparison of the parameter table of the digital night vision camera and the thermal imager in the figure above, it can be found that in fact, the two types of instruments will involve the resolution of the sensor, the size of the built-in display, the magnification of digital magnification, and the function of taking pictures and videos. Wait, these parameters show that the two types of instruments are actually just because of the different types of sensors, and the working principles are actually roughly the same.
5. Comparison of price and cost
Digital night vision cameras and thermal imagers are in the range of thousands to tens of thousands in terms of price, but if you judge from the same price range, it is easy to distinguish which type of instrument is more accepted by the public. For example, at the level of about 10,000 yuan, the digital night vision device is basically about the third generation level, such as ORPHA's DB550L, which is also around 10,000 yuan. The current price level on the market is low resolution and mediocre performance. The imager is out. Of course, it is not that there is no thermal imager that can achieve higher resolution. For example, the RNO-MC640 is currently a higher resolution thermal imager, but the price is around 80,000. What determines its high price is the cost of its core components. The sensor technology of thermal imaging cameras is monopolized by some US military companies such as RNO, while the core components of digital night vision devices have been widely used in various fields and cost. Relatively low. However, it is worth mentioning that the cost of military digital night vision is also very high, and it has not been widely used in the civilian field. In the 21st century, the US military invested heavily in cooperation with Olfa to develop high-quality military digital The night vision device, after 3 years, cost 300 million US dollars, successfully developed a digital night vision forensic device numbered BU3508, which is equipped on various tanks and warships of the US army.
5. About the future prospects of digital night vision and thermal imaging cameras
This article is not intended to explain which is good or bad for digital night vision cameras and thermal imaging cameras, but also to explain the obvious characteristics of the two types of instruments separately. That is the meaning of this article. In fact, there are already very good fusion products for thermal imaging cameras and image-enhancing tube night vision cameras, such as the one shown in the figure below.
Thermal imaging and night vision fusion technology
From the above picture, it can be seen that it is difficult to find people in the shadows when the night vision camera is simply used without infrared assistance, and it is easy to find the target when using the thermal image night vision fusion technology to watch.
Due to the many similarities between its digital night vision cameras and thermal imaging cameras, the integration of the two types of instruments is an inevitable trend. I believe that with the advancement of technology and the popularization of the civilian market, more functional products will be available on the market.
The concept mentioned above is about the popularization of the market. Since the application field of RNO has always been in the military direction, many high-tech products have not been oriented to the civilian market since the beginning, and have been monopolized by the military for a long time. On the contrary, the civilian field of digital night vision has been popularized for a certain period of time, and it is relatively mature. Regardless of the type of product, monopoly is bound to stand still, and only after it reaches the market will it be tested and improved. Looking forward to more new digital night vision cameras and thermal imaging cameras.