Only confined area of people can listen the audio and remaining area is maintained silent. Applications in library, public announcements, military applications etc.

1. Under the guidance of
Mr. Rajendar Reddy
Assistant Professor
Submitted by:
M. VIDYA
14671A04A3

2.  Introduction
 History
 Block Diagram
 Working
 Advantages
 Applications
 Conclusion
CONTENTS

3. INTRODUCTION
What Is Audio Spotlighting???
 Audio spot lighting is a recent technology that
creates a focused beams of sound similar to
light beams coming out of a flashlight.
 By using this we can confine sound into a
smaller area so that targeted listeners can only
hear it.

4. HISTORY
 Invented by the founder of Holosonics Labs,
Dr. F. Joseph Pompei of MIT.
 Audio is made directive using a transducer
array by Ricoh, Japan (1983).
 Disney was amongst the first major
corporations to adopt it for use.

5. BLOCK DIAGRAM
Monolithic
Film
Transducers
Audio Signal
Processor
Audio
PreamplifierMCU
Power
Supply Frequency
Oscillator
Modulator Ultrasonic
Amplifier

6. WORKING
 The original low frequency sound wave such as
human speech is applied to an audio spotlight
emitter device. It modulates low frequency signal
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.

7.  The new generated
sound signal will be
original message
signal of frequency
20hz to 20khz.

8.  We cannot hear the ultrasonic sound, we can hear
the new generated sound formed by non linear
action of air.
 There are two modes of listening. Direct mode and
Reflected mode.

9. ADVANTAGES
 Small Size
 Single Source
 Ultimate control in audio placement
 Minimizes noise pollution
 Ease of installation
 Low maintenance cost and longer life span
 No lag in reproducing sound

10. APPLICATIONS
 Museums and Art galleries
 Military Applications
 Libraries
 Automobiles
 Emergency Rescues
 Public Announcements

11. CONCLUSION
Audio spotlighting system is going to shape the
future of sound and will serve our ears with
magical experience.

12. THANK YOU AND HAVE A
NICE DAY