Eyewear for outputting audio information to the wearer include an eyewear temple, which has at least one loudspeaker. The eyewear temple is configured for placement on an ear of the wearer and spaced apart from an ear opening of the wearer's ear so that the sound waves generated by the loudspeaker are transmitted over the surroundings to the spaced ear opening. The loudspeaker is an ultrasonic loudspeaker. The eyewear has a parametric audio unit that includes the ultrasonic loudspeaker and configured to generate an audible sound beam directed at the ear.

A method is provided for delivering directed transmission of sound waves through modulation on an ultrasonic carrier. In some embodiments, the method comprises connecting at least one directed sound source to an audio system and emitting, via the at least one directed sound source, audio from the audio system, wherein the emitting comprises emitting medium frequency audio sound waves and higher frequency audio sound waves. The audio may be selected via a master control unit, operatively coupled to a mobile application. In some embodiments, a first audio selection is configured to be heard only through a first directed sound source, and a second audio selection is configured to be heard only through a second directed sound source. Additionally, systems and methods are provided for delivering therapeutic sound, through a sinusoidal signal, within an environment intended to cause resonance in certain cells.

An audio system includes a modulated ultrasound audio driver having at least one ultrasound emitter configured to emit an ultrasound signal; at least one acoustic mixer configured to generate an audio signal from the ultrasound signal; and at least one ultrasound receiver configured to detect an ultrasound signal and generate a corresponding electrical signal. A processing unit is configured to process the electrical signal and estimate one or more physical or biometric parameters from the electrical signal. A method for physical or biometric parameter estimation is also disclosed.

Techniques described herein generally relate to generating an audio signal with a speaker. In some examples, a speaker device is described that includes a membrane and a shutter. The membrane can be configured to oscillate along a first directional path and at least one frequency effective to generate an ultrasonic acoustic signal. The shutter is positioned along the propagation of ultrasonic acoustic signal and configured to modulate the ultrasonic acoustic signal such that an audio signal is generated.

A speaker array includes a first speaker device having a first membrane and a first acoustic channel, the first membrane being configured to oscillate and generate a first ultrasonic acoustic signal configured to be transmitted at least partially in the first acoustic channel, the first acoustic channel including at least one dimension comparable to a dimension of a viscous boundary layer of air. A second speaker device includes a second membrane and a second acoustic channel, the second membrane being configured to oscillate and generate a second ultrasonic acoustic signal configured to be transmitted at least partially in the second acoustic channel, the second acoustic channel including at least one dimension comparable to the dimension of the viscous boundary layer of air. An audio output of the speaker array is the combined output of at least the first speaker device and the second speaker device.

An air-pulse generating device includes a membrane structure, a valve structure, and a cover structure. A chamber is formed between the membrane structure, the valve structure and the cover structure. An air wave vibrating at an operating frequency is formed within the chamber. The valve structure is configured to be actuated to perform an open-and-close movement to form at least one opening. The at least one opening connects air inside the chamber with air outside the chamber. The open-and-close movement is synchronous with the operating frequency.

An audio playback method includes the following steps: receiving an ultrasound signal via a microphone; processing the ultrasound signal to obtain a characteristic value of the ultrasound signal; obtaining time lag information based on the characteristic value; and controlling audio delay according to the time lag information.

The present invention discloses a method for producing parametric sound using parametric sound system which is based on ultrasonic electrostatic transducers. It comprises modulation of a carrier ultrasonic signal with a processed audio signal in audio signal processor comprising adaptive frequency filtering based on the audio signal level, dynamic range compression, square root operation, amplification of the modulated ultrasonic signal using a D-class amplifier, driving an electrostatic transducer and generating modulated ultrasonic waves into the air. The electrostatic transducer for the parametric sound system comprises a specific back plate structure that improves electromechanical efficiency of the transducer and also enables realization of a phased array on a single back plate. The disclosed manufacturing method of the electrostatic transducer comprises producing sets of electrodes on the surface of the back plate forming individual cells.

Systems and methods of audio processing and control for improved audibility and performance in a parametric loudspeaker system. The parametric loudspeaker system includes a parametric loudspeaker providing a capacitive load, an output stage having a plurality of switches interconnected in a bridge configuration and connected to the capacitive load of the parametric loudspeaker, and a controller operative to generate a series of pulse width modulation (PWM) pulses, and to generate a plurality of control signals synchronized with the series of PWM pulses for switchingly controlling the plurality of switches in the bridge configuration, thereby driving the capacitive load of the parametric loudspeaker.

An ultrasonic transducer including a membrane film and a perforated baseplate. The baseplate can have a conductive surface with a plurality of perforations formed through the baseplate. The membrane film can have a conductive surface and be positioned under tension proximate to the perforations formed through the baseplate. The tension of the membrane film can be controlled to provide a restoring force to counteract the moving mass of the membrane film, and the moving mass of air in the perforations of the baseplate. By selecting the diameter(s) of the perforations of the baseplate, the thickness of the baseplate, the thickness of the membrane film, the tension of the membrane film, and/or the bending stiffness of the membrane film, a wide bandpass frequency response of the ultrasonic transducer centered at an ultrasonic frequency of interest can be obtained and tailored to a desired application.