Audible Enclaves

Source: TH

Context: Researchers at Penn State have developed audible enclaves for personal sound delivery without headphones.

About Audible Enclaves:

• What are Audible Enclaves?

• Localized pockets of sound heard only at precise intersection points of ultrasonic beams. Enable private audio delivery to individuals in public spaces without disturbing others.

• Localized pockets of sound heard only at precise intersection points of ultrasonic beams.

• Enable private audio delivery to individuals in public spaces without disturbing others.

• Principle Behind Audible Enclaves:

• Nonlinear Acoustic Effect: Two ultrasonic waves intersect and interact non-linearly to generate audible sound only at the intersection point. Use of Metasurfaces: 3D-printed acoustic lenses bend ultrasonic beams along curved paths to meet at a controlled point.

• Nonlinear Acoustic Effect: Two ultrasonic waves intersect and interact non-linearly to generate audible sound only at the intersection point.

• Use of Metasurfaces: 3D-printed acoustic lenses bend ultrasonic beams along curved paths to meet at a controlled point.

• How Audible Enclaves Work:

• Ultrasonic Transducers: Two devices emit ultrasonic beams at slightly different frequencies. Self-Bending Beams: Beams follow crescent-shaped paths due to metasurfaces’ directional control. Intersection Point: Audible sound is produced only where beams intersect, isolating the audio zone. Obstacle Navigation: The beams can bend around human heads or objects, reaching the precise point without disturbance.

• Ultrasonic Transducers: Two devices emit ultrasonic beams at slightly different frequencies.

• Self-Bending Beams: Beams follow crescent-shaped paths due to metasurfaces’ directional control.

• Intersection Point: Audible sound is produced only where beams intersect, isolating the audio zone.

• Obstacle Navigation: The beams can bend around human heads or objects, reaching the precise point without disturbance.

• Key Features:

• Privacy Listening: Audio is only heard by the person within the sound beam intersection, ensuring confidentiality. Virtual Headset Effect: Users can listen without headphones, with no sound leakage to others. Indoor and Outdoor Usability: Tested in reverberant spaces, classrooms, vehicles, and open environments. Directional Sound Control: Can direct sound beams to targeted locations even behind barriers.

• Privacy Listening: Audio is only heard by the person within the sound beam intersection, ensuring confidentiality.

• Virtual Headset Effect: Users can listen without headphones, with no sound leakage to others.

• Indoor and Outdoor Usability: Tested in reverberant spaces, classrooms, vehicles, and open environments.

• Directional Sound Control: Can direct sound beams to targeted locations even behind barriers.

• Limitations:

• Short Range: Currently functional only up to 1 meter from the sound source. Low Sound Intensity: Output is limited to around 60 decibels, equivalent to a normal conversation. Power Limitations: Increasing range or volume requires higher ultrasonic beam intensity. Environmental Dependence: Effectiveness may reduce in noisy or unpredictable outdoor conditions.

• Short Range: Currently functional only up to 1 meter from the sound source.

• Low Sound Intensity: Output is limited to around 60 decibels, equivalent to a normal conversation.

• Power Limitations: Increasing range or volume requires higher ultrasonic beam intensity.

• Environmental Dependence: Effectiveness may reduce in noisy or unpredictable outdoor conditions.