Editor’s note: This article is from Ai Fan’er, author Li Chaofan, 36 氪 released with permission.Facial recognition has been widely used. In addition to unlocking the face on mobile phones, it is also used by the police for daily law enforcement. Among them, there have been several fugitive criminals who used facial recognition in Jacky Cheung ’s concert. However, this type of facial recognition also has many restrictions.Concert scene security gates can only be accurately identified in a fixed light scene.If the distance is tens of meters away in the dark, this facial recognition technology is often powerless.However, the US military is currently developing a new facial recognition technology that can recognize human faces at long distances in the dark. The technical principle used is also very common, that is, infrared thermal imaging technology.This technology has become very common in the military field, and night vision devices use this technology.Infrared thermal imaging is different from visible light imaging such as cameras. It can identify thermal radiation generated by objects and form different infrared images.However, it is very difficult to identify a person’s identity only through thermal imaging. Night vision devices generally can only identify whether the target is a living object, and the outline of the face in the infrared image is also very blurred, so it is difficult to determine who the other party is.So how does the US military use infrared thermal imaging for facial recognition?Previously, The Register reported that the US Army Research Laboratory used an AI-based image synthesis method to extract features such as eyes, nose, and lips from the blurred infrared image of the face, and then restored sketch-like portrait images through algorithms.Researchers selected 60 people’s visible light image and infrared face image to build a database and experimented, and found that the recognition using this method was more than 80% accurate.However, the accuracy rate of mature face recognition technologies on the market has exceeded 99%. The recognition accuracy of 80% is still a long way from practical application. However, if this technology is otherwise inferior to the current face recognition technology,Fewer advantages.Using infrared thermal imaging technology for face recognition, you no longer have to worry about being affected by lighting conditions. Compared with visible light face recognition, infrared thermal imaging is also less susceptible to factors such as makeup and masks. Some time ago an American AI companyUse 3D masks to cheat too many personal face recognition systems, and infrared thermal imaging can “see through” the face directly under the mask.Last year, the U.S. military also increased its investment in infrared thermal face recognition technology. According to financial data from the U.S. Department of Defense, the U.S. military signed a $ 4.5 million contract with an infrared thermal imaging technology company called Polaris Sensor Technologies last September.Let this company help develop the technology, and the entire project will continue until 2021.▲ Polaris Sensor Technologies ’infrared imaging products. Relevant documents show that the U.S. military hopes that this technology can complete face recognition under various occlusion conditions, such as automotive windshield and backlight conditions.Or fog and other scenes, but also integrated into a personal device that is portable enough to be identified at a distance of 10-500 meters.Polaris Sensor Technologies has accumulated a lot of technology in the field of infrared thermal imaging. Among them, there is a patent dedicated to infrared facial recognition, which can greatly improve the accuracy of infrared image recognition through algorithms.In order to cope with scenes that are not convenient for face recognition at night and at long distances, in addition to infrared thermal imaging face recognition, the US military has even tried to use heartbeats to perform long-range recognition of people.According to the MIT Technology Review, The Pentagon has developed a new device, Jetso, that can detect surface motion caused by a heartbeat using laser vibration measurement technology within 200 meters, because the heart is characterized by the irisBiological characteristics that cannot be altered and disguised may be used to identify different individuals.If these technologies are more mature, law enforcement agencies will greatly improve the efficiency of arresting criminals, but it also means that face recognition systems will be more difficult to detect in daily life. If people and institutions using this technology are not subject to sufficient strict supervisionThe consequences are also terrifying.