US Patent 12113901 Authentication device, system and method

The present invention relates to secure transmission and reception of electronic messages using an authentication device. The authentication device includes a light sensor that is used to scan a visual element displayed on a display of a user device in conjunction with an electronic message having an encrypted payload. The visual element encodes a unique identifier that the authentication device transmits to a server, receiving in response a cryptographic key stored in association with the unique identifier and usable to decrypt an encrypted payload of the electronic message. The authentication device can also generate encryption keys and corresponding unique identifiers suitable for encryption of payloads of electronic messages.