Audio spotlighting is a technology that uses ultrasonic frequencies to create a narrow, directed beam of sound similar to a flashlight beam. It was invented in the 1970s and works by modulating audible sound with ultrasonic tones, using the nonlinearity of air to produce new audible frequencies within the beam. This allows sound to be focused on a small area or person, avoiding noise pollution and allowing multiple listeners to hear different sounds nearby. Potential applications include public announcements, entertainment systems, and military uses.

2. IS IT POSSIBLE TO CONFINE
SOUND TO A SMALL AREA ?
YES. It is possible!!
through…
AUDIO SPOTLIGHTING

3. What is Audio spotlight?

4. A technology that creates focused beams of sound similar
to light beams coming out of a flashlight.
By shining sound to one location specific listeners can
be targeted.
Ultrasonic energy to create extremely narrow beams of
sound that behave like beams of light.
Introduction

5. History
 Invented by the founder of Holosonics Labs, Dr. F.
Joseph Pompei of MIT.
 First attempts created a single tone (1975).
 Audio tone made directive using a transducer array by
Ricoh, Japan (1983).
 Commercially available in 2000 by the company
Holosonics.
 Disney was amongst the first major corporations to
adopt it for use.

6. AUDIO SPOTLIGHT looks like a disk-shaped
loudspeaker trailing a wire with a small laser guide beam
mounted in the middle
 When one points the
flat side of the disk in
your direction, you
here whatever sound
one’s chosen for you.

7. Basic Principle
works by emitting harmless high frequency ultrasonic
tones that human ear cannot hear.

8.  Parametric array employs the non linearity
of the air to create audible by products from
inaudible ultrasonic sound , resulting in extremely
directive and beam-like sound

9. PARAMETRIC LOUDSPEAKER- AMAZING AUDIO
SPOTLIGHT

10.  Low Beam Angle is required to focus the sound.
Beam angle of audible sound is very wide,
about 360°
 The smaller the wave length ,the lesser the Beam
angle.
 Another way to focus sound is to use loudspeaker
with larger Aperture size.
But….
A few conditions are to be satisfied

11. Working
 The original low frequency sound wave such as human
speech or music is applied into an audio spotlight emitter
device.
 This low frequency signal is frequency
modulated with ultrasonic frequencies.
 Since the wavelength is smaller the beam angle will be
around 3 degree, as a result the sound beam will be a
narrow one with a small dispersion.

12. AUDIO SPOTLIGHTING EMITTER

13. Modulated signal travels through the air.
Due to the nonlinearity property of air new sounds
are formed within the wave.
 The new frequencies will be added into the sound
wave by the air itself.
 frequency in the range of 20 Hz to 20 KHz .
 Since we cannot hear the ultrasonic sound, we
only hear the new sounds that are formed by the
nonlinear action of the air

14. RANGE OF HEARING
 Human ear - 20 Hz to20,000Hz.
 No single loud speaker can operate efficiently
over such wide range of frequencies.
 By using this technology it is possible to design
a perfect transducer which can work over a
wide range of frequency which is audible to the
human ear.

15. CONVENTIONAL LOUD SPEAKER
Vs AUDIO SPOTLIGHT
• CONVENTIONAL
SPEAKERS
• AUDIO-SPOTLIGHTG

16. COMPONENTS OF AUDIO SPOTLIGHTING
SYSTEM
 Power Supply.
 Frequency oscillator.
 Modulator.
 Audio signal processor.
 Microcontroller.
 Ultrasonic amplifier.
 Transducer.

17. BLOCK DIAGRAM

18. HOW TO USE AUDIO SPOTLIGHT ?
There are two ways to use Audio Spotlight.
First it can direct sound at a specific target creating
a contained area of listening space which is called
“Direct Audio”.
Second it can bounce off of a second object
creating an audio image which is called the “Projected
Audio” or the Virtual mode.

19. Direct Mode:
Requires a clear line of approach from the
sound system unit to the point where the listener can hear the
audio. To restrict the audio in a specific area this method
is appropriate.
Projected or Virtual mode:
For this mode of operation the sound beam from an emitte
r is made to reflect from a reflecting surface.
A virtual sound source creates an illusion of sound source that
emanates from a surface.
This method is appropriate when we want to
send the information to a large number of people.

21. Features
 Can focus sound only at the specific place one’s
want.
 Sharper directivity than conventional
loudspeakers.
 Uses non-linearity of air for demodulation.
 Focused or directed sound travel much faster.
 Highly cost effective.
 No lag in reproducing the sound & requires low
power.

22.  Small size
 Single source
 Ultimate control in audio placement
 Minimizes noise pollution
 Ease of installation
 Lowest maintenance cost
 Reduced feedback
ADVANTAGES

23. DISADVANTAGES
 Lack of mass production. i.e, each unit
must be hand made.
 The most common form of distortion
is clipping.

24. APPLICATIONS
AUTOMOBILES RETAIL SALES

25. PUBLIC ANNOUNCEMENT MUSEUMS

26. MILITARY APPLICATIONSENTERTAINMENT SYSTEMS

27. two persons can hear different sound
standing close to each other
Audio Spotlight speakers allow
visitor to enjoy music while other
read nearby peace & quiet
Audio/video conferencing
Sound Bullets

28. THE FUTURE OF AUDIO SPOT
LIGHTING
 Holds the promise of replacing conventional
speakers.
 It allows the user to control the
direction of propagation of sound. Will force the
people to rethink their relationship with the sound.
 It really
“Puts the sound where you want it”.

29.  Audio spotlighting is really going to make a
revolution in sound transmission and the user
can decide the path in which audio signal
should propagate.
 Due to the unidirectional
propagation it finds application in large number of
fields.
 Audio spotlighting system is
going to shape the future of sound and will serve
our ears with magical experience..
CONCLUSION
“A REAL BOON TO THE FUTURE”