According to foreign media reports on April 24th Beijing time, the US Patent and Trademark Office granted Apple a patent for a brand-new data transfer technology on Tuesday. Using this patent, one device can take a picture of another device using its built-in camera and extract a digital handshake key from the photo taken to establish secure data transmission between the two devices.The name of this patent is inter-device digital handshake technology, which covers the technology of generating a digital handshake key using photos and establishing a secure communication channel between devices.According to the patent description file, modern portable devices such as iPhones can store a large amount of digital content, such as contacts, text files, videos, and music. Currently, most users transfer such content between devices through email or sending text messages. Although it is convenient to copy and paste content, this method of content transfer is monotonous and boring.In addition, devices can also use wireless technologies such as Bluetooth or Wi-Fi to transmit data and establish direct, fast communication channels. However, these methods all require both devices to use the same network key, and the current methods for generating such keys are very limited.Although there are currently some applications that can quickly generate keys, such as Bump application, which can establish a connection when two devices output similar collision accelerometer data, both devices must be equipped with motion sensors; otherwise, a connection cannot be established.Apple's patent invention stipulates that the device photo will contain a key. For example, the second device can display a dynamic key on the screen or have a key embedded in its casing. Hidden keys can be displayed through filters, flashlights, or infrared rays. In some cases, a dedicated chip must be integrated into the phone's camera module to detect and crack the device's key.Next, a digital handshake key is generated using the key provided by the device or the key captured by the photo. Using this digital handshake key, the two devices can establish a connection, share content, and transmit part or all of the displayed content according to user settings. This technology supports multiple devices to establish connections.In addition, this digital handshake technology can also be used as an identification system to authorize devices to access some protected information. For example, it can be used to confirm the user's identity when the user buys prescription drugs, etc.Apple's camera-based digital handshake technology patent was first applied for in 2010, and the patent inventors were Marcel Van Os and Caroline Cranfill.