Targeted Audio Messaging Technologies

What laser, ultrasonic, or similar technologies exist or are in development that can project an audio message to a targeted person or group without a receiver?  DSIAC was tasked with researching technologies and research and development projects that can project an audio message to a targeted person or group.  Research focused on ultrasonic and laser technologies.  To collect relevant information, DSIAC created an active technical inquiry announcement on the DSIAC webpage and a forum page on DTIC’s DoDTechSpace limited distribution website and searched open sources and the DTIC Research and Engineering Gateway repository.  Technologies and projects from a variety of service and contractor agencies, national laboratories, and commercial industries were compiled and summarized into a report delivered to the inquirer, along with contact information.  White papers and technical reports delivered to DSIAC as supplementary information were also forwarded to the inquirer.