1. Holographic Whisper:
Rendering audible sound spots in
three-dimensional space by focusing ultrasonic waves
Yoichi Ochiai*13, Takayuki Hoshi*23, Ippei Suzuki*1
*1 University of Tsukuba, Digital Nature Group *2 University of Tokyo, *3 Pixie Dust Technologies, inc.
*joint first authorship, Contact: wizard@slis.tsukuba.ac.jp
Assistant Professor at University of Tsukuba, Head of Digital Nature Group
CEO of Pixie Dust Technologies, inc

2. Motivation and Introduction
“Render the Aerial Sound Sources separated from Machines”
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.

3. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
We envision the post-pixel world
Release data from material existence
and regenerate Material Properties
by using out of range frequencies of our sensory organs.
P i x e l s P i x i e s
2D to 2.5D
Physical Device
3 D
C o m p u t a t i o n a l W a v e D e s i g n
M a g i c a l E x p e r i e n c e
w i t h N o C o n t a c t D e v i c e
T o w a r d s

4. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Pixel Image
Haptic
Haptic
Sound
Manipulation
2.5D
Voxel
Human
How can we update
the pixel world (2.5D)
towards pixie world (3D)?
Scenery of 2000s to 2020
2.5D device
Physical Laptops
Traditional Scenery

5. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Post-Pixel Alternatives By Computational Wave Synthesis
Manipulation of Object
Aerial HapticsAerial Image
and Haptics
Voxel Graphics
holographic laser plasma
Holographic
laser plasma and ultrasonic
holographic ultrasonic levitation
holographic ultrasonic levitation
We have studied to envision the alternatives
by computational wave synthesis.

6. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Post-Pixel Alternatives By Computational Wave Synthesis
Manipulation of Object
Aerial HapticsAerial Image
and Haptics
Voxel Graphics
holographic laser plasma
Holographic
laser plasma and ultrasonic
holographic ultrasonic levitation
holographic ultrasonic levitation
Next! Holographic Audio
We have studied to envision the alternatives
by computational wave synthesis.

7. U n i v e r s i t y o f Ts u k u b a , Yo i c h i O c h i a i L a b r a t o r y

8. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Towards three dimensional audio communication
19c-20c 1990-
Broad Ultrasonic Beam
Mass-Communication Towards Individual Communication
ABC.com, Ponpei,et,al.
2017-
Holographic Points
and Steerable Beams
Towards Personalized Communication
with Ubiquitous Environment
Our Study

9. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Overview
Designing narrow audio distribution for individual communication
Our Study
Conventional

10. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Contribution
The method enables production of aerial sound point sources
with an ultrasonic phased array for three-dimensional (3D)
audio interaction which includes:
Principles
Theory
Simulated Result
Implementation
User Study
Evaluation
Application
Discussion

11. Related Works
“How to design the Acoustic Environment”
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.

12. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
The Audio Communication
Audible Communication has been separated since Edisons Era.
Individual Broad

14. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Efforts towards Holographic Individual Audio
[3]BOSE. F1 flexible array loudspeaker system. from http://www.bose.com/prc.jsp?url=/promotions/entry_pages/f1/index_en.jsp
[4]JBL. IntelliDisc-DS90. from http://www.jblpro.com/www/products/installed-sound/intellidisc-ds90
[5]M. Yoneyama, J. Fujimoto, Y. Kawamo, and S. Sasabe. 1983. The audio spotlight: An application of nonlinear interaction of sound waves to a new type of loudspeaker design. The Journal of the Acoustical Society of
America 73, 5, 1532-1536.
[6]K. Aoki, T. Kamakura, and Y. Kumamoto. 1991. Parametric loudspeaker - Characteristics of acoustic field and suitable modulation of carrier ultrasound, Electronics and Communications in Japan 74, 9, 76-82.
[7]F.J. Pompei. 1999. The use of airborne ultrasonics for generating audible sound beams, Journal of the Audio Engineering Society 47, 9, 726-731.
[9]K. Shinagawa, Y. Amemiya, H. Takemura, S. Kagami, and H. Mizoguchi. 2007. Three dimensional simulation and measurement of sound pressure distribution generated by 120 ch plane loudspeaker array. In Proceedings of
IEEE International Conference on Systems, Man and Cybernetics, 278-283.
[10]T. Matsui, D. Ikefuji, M. Nakayama, and T. Nishiura. 2014. Multiple audio spots design based on separating emission of carrier and sideband waves. In Proceedings of International Congress and Exposition on Noise
Control Engineering, 6313-6317.
[12]C. Shi, Y. Kajikawa, and W.-S. Gan. 2014. An overview of directivity control methods of the parametric array loudspeaker. APSIPA Transactions on Signal and Information Processing 3, e20.
ABC.com, Ponpei,et,al.

15. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Efforts towards Holographic Individual Audio
[3]BOSE. F1 flexible array loudspeaker system. from http://www.bose.com/prc.jsp?url=/promotions/entry_pages/f1/index_en.jsp
[4]JBL. IntelliDisc-DS90. from http://www.jblpro.com/www/products/installed-sound/intellidisc-ds90
[5]M. Yoneyama, J. Fujimoto, Y. Kawamo, and S. Sasabe. 1983. The audio spotlight: An application of nonlinear interaction of sound waves to a new type of loudspeaker design. The Journal of the Acoustical Society of
America 73, 5, 1532-1536.
[6]K. Aoki, T. Kamakura, and Y. Kumamoto. 1991. Parametric loudspeaker - Characteristics of acoustic field and suitable modulation of carrier ultrasound, Electronics and Communications in Japan 74, 9, 76-82.
[7]F.J. Pompei. 1999. The use of airborne ultrasonics for generating audible sound beams, Journal of the Audio Engineering Society 47, 9, 726-731.
[9]K. Shinagawa, Y. Amemiya, H. Takemura, S. Kagami, and H. Mizoguchi. 2007. Three dimensional simulation and measurement of sound pressure distribution generated by 120 ch plane loudspeaker array. In Proceedings of
IEEE International Conference on Systems, Man and Cybernetics, 278-283.
[10]T. Matsui, D. Ikefuji, M. Nakayama, and T. Nishiura. 2014. Multiple audio spots design based on separating emission of carrier and sideband waves. In Proceedings of International Congress and Exposition on Noise
Control Engineering, 6313-6317.
[12]C. Shi, Y. Kajikawa, and W.-S. Gan. 2014. An overview of directivity control methods of the parametric array loudspeaker. APSIPA Transactions on Signal and Information Processing 3, e20.
ABC.com, Ponpei,et,al.
Pickup

16. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
How the ultrasonic directional audio works?
Why???
How did it achieved?

17. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Beam Forming
[5]M. Yoneyama, J. Fujimoto, Y. Kawamo, and S. Sasabe. 1983. The audio spotlight: An application of nonlinear interaction of sound waves to a new type of loudspeaker design. The Journal of the Acoustical Society of America
73, 5, 1532-1536.
[6]K. Aoki, T. Kamakura, and Y. Kumamoto. 1991. Parametric loudspeaker - Characteristics of acoustic field and suitable modulation of carrier ultrasound, Electronics and Communications in Japan 74, 9, 76-82.
[7]F.J. Pompei. 1999. The use of airborne ultrasonics for generating audible sound beams, Journal of the Audio Engineering Society 47, 9, 726-731.

18. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Beam Forming
[5]M. Yoneyama, J. Fujimoto, Y. Kawamo, and S. Sasabe. 1983. The audio spotlight: An application of nonlinear interaction of sound waves to a new type of loudspeaker design. The Journal of the Acoustical Society of America
73, 5, 1532-1536.
[6]K. Aoki, T. Kamakura, and Y. Kumamoto. 1991. Parametric loudspeaker - Characteristics of acoustic field and suitable modulation of carrier ultrasound, Electronics and Communications in Japan 74, 9, 76-82.
[7]F.J. Pompei. 1999. The use of airborne ultrasonics for generating audible sound beams, Journal of the Audio Engineering Society 47, 9, 726-731.

19. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Beam Forming
WaveFront = Plane Wave = Sound Beam
[5]M. Yoneyama, J. Fujimoto, Y. Kawamo, and S. Sasabe. 1983. The audio spotlight: An application of nonlinear interaction of sound waves to a new type of loudspeaker design. The Journal of the Acoustical Society of America
73, 5, 1532-1536.
[6]K. Aoki, T. Kamakura, and Y. Kumamoto. 1991. Parametric loudspeaker - Characteristics of acoustic field and suitable modulation of carrier ultrasound, Electronics and Communications in Japan 74, 9, 76-82.
[7]F.J. Pompei. 1999. The use of airborne ultrasonics for generating audible sound beams, Journal of the Audio Engineering Society 47, 9, 726-731.

20. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Beam Forming
WaveFront = Plane Wave = Sound Beam
[5]M. Yoneyama, J. Fujimoto, Y. Kawamo, and S. Sasabe. 1983. The audio spotlight: An application of nonlinear interaction of sound waves to a new type of loudspeaker design. The Journal of the Acoustical Society of America
73, 5, 1532-1536.
[6]K. Aoki, T. Kamakura, and Y. Kumamoto. 1991. Parametric loudspeaker - Characteristics of acoustic field and suitable modulation of carrier ultrasound, Electronics and Communications in Japan 74, 9, 76-82.
[7]F.J. Pompei. 1999. The use of airborne ultrasonics for generating audible sound beams, Journal of the Audio Engineering Society 47, 9, 726-731.

21. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Beam Forming
WaveFront = Plane Wave = Sound Beam
ex. LASER
Coherent Plane Wave
[5]M. Yoneyama, J. Fujimoto, Y. Kawamo, and S. Sasabe. 1983. The audio spotlight: An application of nonlinear interaction of sound waves to a new type of loudspeaker design. The Journal of the Acoustical Society of America
73, 5, 1532-1536.
[6]K. Aoki, T. Kamakura, and Y. Kumamoto. 1991. Parametric loudspeaker - Characteristics of acoustic field and suitable modulation of carrier ultrasound, Electronics and Communications in Japan 74, 9, 76-82.
[7]F.J. Pompei. 1999. The use of airborne ultrasonics for generating audible sound beams, Journal of the Audio Engineering Society 47, 9, 726-731.

22. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Ultrasonic Self-demodulation generates audible sound
temporal change of ultrasonic (primary) waves
the radiation of audible sound (secondary) waves
where c [m/s] is the speed of sound in air, β is the
nonlinear parameter, and ρ [kg/m3] is the mass
density of air
Audible
Ultrasonic
→In the beam you can hear the audible sound

23. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Ultrasonic Self-demodulation generates audible sound
temporal change of ultrasonic (primary) waves
the radiation of audible sound (secondary) waves
where c [m/s] is the speed of sound in air, β is the
nonlinear parameter, and ρ [kg/m3] is the mass
density of air
Audible
Ultrasonic
→In the beam you can hear the audible sound

24. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Beam Forming to the point audio
[10]T. Matsui, D. Ikefuji, M. Nakayama, and T. Nishiura. 2014.
Multiple audio spots design based on separating emission of
carrier and sideband waves. In Proceedings of International
Congress and Exposition on Noise Control Engineering,
6313-6317.

25. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Beam Forming to the point audio
[10]T. Matsui, D. Ikefuji, M. Nakayama, and T. Nishiura. 2014.
Multiple audio spots design based on separating emission of
carrier and sideband waves. In Proceedings of International
Congress and Exposition on Noise Control Engineering,
6313-6317.

26. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Beam Forming to the point audio
Audible
Area
[10]T. Matsui, D. Ikefuji, M. Nakayama, and T. Nishiura. 2014.
Multiple audio spots design based on separating emission of
carrier and sideband waves. In Proceedings of International
Congress and Exposition on Noise Control Engineering,
6313-6317.

27. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Steering Beam
[12]C. Shi, Y. Kajikawa, and W.-S. Gan. 2014. An overview of directivity control methods of the parametric array loudspeaker. APSIPA Transactions on Signal and Information Processing 3, e20.
θ [rad]: When the spacing
between the transducers is d [m] in the case of a 1D
transducer array,
the phase delay of the i-th transducer, ∆φi [rad]
where k [rad/m] is the wavenumber of the ultrasound.

28. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Steering Beam
[12]C. Shi, Y. Kajikawa, and W.-S. Gan. 2014. An overview of directivity control methods of the parametric array loudspeaker. APSIPA Transactions on Signal and Information Processing 3, e20.
θ [rad]: When the spacing
between the transducers is d [m] in the case of a 1D
transducer array,
the phase delay of the i-th transducer, ∆φi [rad]
where k [rad/m] is the wavenumber of the ultrasound.

29. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Steering Beam
WaveFront = Plane wave = Beam
[12]C. Shi, Y. Kajikawa, and W.-S. Gan. 2014. An overview of directivity control methods of the parametric array loudspeaker. APSIPA Transactions on Signal and Information Processing 3, e20.
θ [rad]: When the spacing
between the transducers is d [m] in the case of a 1D
transducer array,
the phase delay of the i-th transducer, ∆φi [rad]
where k [rad/m] is the wavenumber of the ultrasound.

30. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Steering Beam
WaveFront = Plane wave = Beam
[12]C. Shi, Y. Kajikawa, and W.-S. Gan. 2014. An overview of directivity control methods of the parametric array loudspeaker. APSIPA Transactions on Signal and Information Processing 3, e20.
θ [rad]: When the spacing
between the transducers is d [m] in the case of a 1D
transducer array,
the phase delay of the i-th transducer, ∆φi [rad]
where k [rad/m] is the wavenumber of the ultrasound.

31. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Sound Focus

32. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Sound Focus

33. WaveFront
= Spherical Wave
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Sound Focus

34. WaveFront
= Spherical Wave
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Sound Focus

35. WaveFront
= Spherical Wave
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Sound Focus
Focal Point

36. WaveFront
= Spherical Wave
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Sound Focus
Focal Point
Objective Lens
Plasma
ex. LASER
Coherent
Spherical
Wave
Focal
Point
Hoshi et al, 2008

38. PTH:
Audible-sound radiation threshold,
self-demodulation effect becomes
obvious when Pu is effectively
high and its square value is not
negligible.
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Make it narrow area: Threshold of self-demodulation
temporal change of ultrasonic (primary) waves
the radiation of audible sound (secondary) waves
where c [m/s] is the speed of sound in air, β is the
nonlinear parameter, and ρ [kg/m3] is the mass
density of air
Audible
Area
Pu > PTH

39. *notice: recording mic is more sensitive than human auditory
& reflection of mic itself recorded
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Recorded Sound

40. *notice: recording mic is more sensitive than human auditory
& reflection of mic itself recorded
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Recorded Sound

41. Implementation
“Designing Holographic Loudspeaker”
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.

42. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Electrical Circuit Design

43. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Phase Modulation

44. Evaluation
“How to design the Acoustic Environment”
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.

45. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Audio Distribution
targetnoise by interference
Ex, Ultrasonic
Super-directional Speaker

46. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Audio Distribution
targetnoise by interference
Ex, Ultrasonic
Super-directional Speaker
Minimum Focal Area: 20mm x 20mm
Focal Area: 1600mm x 1600mm

47. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Simulated Results of the Shape of Sound Source
The size of speaker decides fundamental limitation of beam forming.

48. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
User Study1
Direction and Location
for x-y plane
is understandable for users.
x
y
Z

49. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
User Study2
User can distinguish
these three points (Z axis)
x
y
Z

50. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
User Study3
Precise audible height
perception is not easy
for users (for Z axis)
x
y
Z

51. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Results and User Study2&3
Make Larger Difference (Z).
or Change the x-y Direction
x
y
Z

52. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Sound Quality
*notice: recording mic is more sensitive than human auditory & reflection of mic itself recorded

53. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Sound Quality
*notice: recording mic is more sensitive than human auditory & reflection of mic itself recorded

54. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Sound Quality
conventional conventional This studyoriginalwave shape
FFT spectrums

55. Application
“I can hear Holographic Whisper”
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.

56. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Application for Interaction
Interactive Sound Distribution
Features for Novel Applications
Narrow and Broad
Trace and Focus
Haptic and Push

57. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Place the sound spot, more precise and interactive

58. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Application for Interaction (Focusing inner music instruments)

59. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Application for Interaction (Whispered Voxels)

60. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Place the sound spot for pick up target

61. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Super Narrow Distribution for spotting captions

62. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Super Narrow Distribution (active design of sound field)

63. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Super Narrow and Wide Distribution Switchable

64. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Super Narrow and Wide Distribution Switchable
training and instruction

65. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
3D manipulation of Object with Audible Annotations

66. Audible Information
can be recognized
separately.
Audible Information
can not be delivered
separately.
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
This technique will expand audio recognitions

68. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Possible Scenario Super Narrow Distribution
Make Sound Difference
navigation play
shopping

69. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Super Narrow Distribution (combine with large monitor)
User A
User B
User C
Individual Audio Interaction for voice control

70. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Super Narrow Distribution (Multi-language conference)

71. Discussion and Conclusion
“Summery of Holographic Whisper”
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.

72. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Discussions
Ultrasound exposure
Multiple Sound Points by CGH
It cannot say no effect. Lower than conventional ones
(because this methods generate radiation point
Lower intensity than haptic device
Available by generating multiple focus by multiple modulation.
but it limited spatiotemporal resolution.
Lower intensity(eg.haptic)
Direct Exposure is not
necessary
Available
Advantage
Advantage

73. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Discussions
Amplitude of Audio Signals
Grating Lobes
Audible
Ultrasonic
Amplitude of Audio signal decides the characteristics
of sound focus, it is typical trade off of this methods.
it generates grating lobes around the focus (40 degree).
This is typical limitation of this methods.
It affects both amplitude
and audio distribution
It generated around the
focal point
limitation and tradeoff
limitation and tradeoff

74. Discussions
The size of speaker decides fundamental limitation of beam forming.
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Discussions

75. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Overview
Designing narrow audio distribution for individual communication
Our Study
Conventional

76. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Conclusion
Production of aerial sound point sources with an ultrasonic phased
array for three-dimensional (3D) audio interaction
includes:
Principles
Theory
Simulated Result
Implementation
User Study
Evaluation
Application
Discussion

77. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
We envision the post-pixel world
Release data from material existence
and regenerate Material Properties
by using our of range of our sensory organs.
P i x e l s P i x i e s
2D to 2.5D 3 D

78. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Team
Dr. Yoichi Ochiai
Assistant Prof, Advisor to President
Head of Digital Nature Group,
University of Tsukuba
CEO and coFounder
of Pixie Dust Technologies, inc.
Dr. Takayuki Hoshi
Assistant Prof, University of Tokyo
co Founder
of Pixie Dust Technologies, inc.
Ippei Suzuki
Undergrad Student,
Digital Nature Group,
University of Tsukuba
U n i v e r s i t y o f Ts u k u b a , Yo i c h i O c h i a i L a b r a t o r y

79. Holographic Whisper:
Rendering audible sound spots in
three-dimensional space by focusing ultrasonic waves
Yoichi Ochiai*13, Takayuki Hoshi*23, Ippei Suzuki*1
*1 University of Tsukuba, Digital Nature Group *2 University of Tokyo, *3 Pixie Dust Technologies, inc.
*joint first authorship, Contact: wizard@slis.tsukuba.ac.jp
Assistant Professor at University of Tsukuba, Head of Digital Nature Group
CEO of Pixie Dust Technologies, inc

80. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
FAQ
Oh what amazing! Can I buy?
Yes, you can buy soon ( this year)
We provide this technique for B to B for now.
Is it safe???
Our auditory is sensible and
it quite lower intensity than
Ultrasonic Haptic Applications
call or mail
Oh, complex!! Just Use Headphones! Easy!
Nice idea,
it can suppress others voice to concentrate.

81. What is the next Challenge
towards Post Multimedia?
(Post Pixels interaction)
Visual:
HD(1080p) in Space
60Hz in Time
Audio:
22.1kHz in Time
U n i v e r s i t y o f Ts u k u b a , Yo i c h i O c h i a i L a b r a t o r y
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Go out of the range

82. What is the next Challenge
towards Post Multimedia?
(Post Pixels interaction)
Visual:
HD(1080p) in Space
60Hz in Time
Audio:
22.1kHz in Time
Multimedia systems are restricted
from limitation and imitation of
the spec of human sensory organs
U n i v e r s i t y o f Ts u k u b a , Yo i c h i O c h i a i L a b r a t o r y
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Go out of the range

83. What is the next Challenge
towards Post Multimedia?
(Post Pixels interaction)
Visual:
HD(1080p) in Space
60Hz in Time
Audio:
22.1kHz in Time
Multimedia systems are restricted
from limitation and imitation of
the spec of human sensory organs
1.High Intensity
2.High Resolution
3.True Holography
U n i v e r s i t y o f Ts u k u b a , Yo i c h i O c h i a i L a b r a t o r y
Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
Go out of the range

85. U n i v e r s i t y o f Ts u k u b a , Yo i c h i O c h i a i L a b r a t o r y

86. “Focused Ultrasound and Lasers by Field Generators” U n i v e r s i t y o f Ts u k u b a , Yo i c h i O c h i a i L a b r a t o r y
Spatial light modulator
(SLM)
CGH
Laser
Lens
Focal Points
Acoustic
Optic
Modulation on Reflection
Time delay generation
Acoustic Pressure and Standing Waves
Laser Induced Plasma

89. Copyright Yoichi Ochiai, University of Tsukuba, Digital Nature Group, Pixie Dust Technologies, inc.
We envision the post-pixel world
Release data from material existence
and regenerate Material Properties
by using out of range frequencies of our sensory organs.
P i x e l s P i x i e s
2D to 2.5D
Physical Device
3 D
C o m p u t a t i o n a l W a v e D e s i g n
M a g i c a l E x p e r i e n c e
w i t h N o C o n t a c t D e v i c e
T o w a r d s