Selected Papers

The t-Room—Toward the Future Phone
Keiji Hirata†, Yasunori Harada, Toshihiro Takada,
Shigemi Aoyagi, Yoshinari Shirai, Naomi Yamashita,
and Junji Yamato
Abstract
The t-Room is a remote computer supported cooperative work (CSCW) system that we are developing. Our approach is to build rooms with an identical layout, including walls of display screens on whichusers and physical or virtual objects are all shown at life size, and to provide symmetry of awareness andimmersion in each other’s physical space. This allows users in the t-Rooms to feel as if they were in thesame room. Furthermore, by introducing recording and playback capabilities to the activities that occur
within the t-Room, we can achieve asynchronous communication that overcomes the temporal barrier.
The t-Room has greater potential to reproduce reality and awareness in remote collaboration than conventional videoconferencing systems. Moreover, as a step toward the future phone, it will enable us to
implement a wide variety of telecommunication services that give the feeling of being in the same roomand to create a new social interaction style through a large-scale immersive user interface.

1. Introduction
Even with the availability of videoconferencing
systems (VCSs), there are still occasions when there
is no substitute for direct face-to-face discussions.
Conventional VCSs have aimed to create a strong
feeling of presence by using high-quality audio andvideo and virtual reality technology. However, they
do not fully recreate the interactions that naturally
take place between people who are gathered in thesame room. For example, if one person (John) sees
another person (Mary) from a diagonal perspective,then Mary should also see John from a diagonal perspective. The apparent distance of John from Maryshould also match the apparent distance of Mary fromJohn. If John moves, then his apparent direction anddistance from Mary should correspondingly change,
and vice versa. Their positional relationship should
also be immediately apparent to a third person who is† NTT Communication Science Laboratories
Soraku-gun, 619-0237 Japan
Email: hirata@brl.ntt.co.jp

26

viewing them from the side. These phenomena thatpeople take for granted when they are all in the sameroom are not conveyed by conventional VCSs. We
have developed an advanced telecommunication system called the “t-Room” that creates the feeling of
being in the same room for users who are actually
separated spatially. To overcome the spatial barrier,
we use the simple approach of building rooms with an
identical layout, including walls of display screens on
which users and physical or virtual objects are allshown at life size.
In addition to overcoming the spatial barrier, we
think it is important to support collaboration amongpeople in different time zones, time senses, and timescales. For example, when people in Europe have ameeting at 10 am with people in the USA, the people
in the USA have to stay awake until midnight and discuss serious matters while fighting off sleepiness.
Arranging a meeting among busy users is always
tough, and often people want to postpone participation in a less important meeting because they givehigher priority to more pressing tasks. Commonlyused asynchronous media, such as email, mailing
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lists, BBSs (bulletin board systems), and blogs (weblogs), enable people to contribute to communication
at a convenient time, and these media seem to overcome the temporal barrier that exists in VCSs. We
have observed that quotations in email and citations
in a BBS play a reference role and thus facilitate akind of interactivity that is different from that in faceto-face communication. The t-Room also overcomes
the temporal barrier by enabling a present user toshare the awareness information of users in a cited orquoted fragment. We have developed a video editor
that can handle the input and output of continuous
multistream video and sound data with citation or
quotation functions.
To convey the feeling of being in the same room as
people who were present at other times, the t-Roomallows an earlier conference to be recorded andplayed back during a later conference. This later conference can itself be recorded and played back during
another conference in the future. This playback feature plays a role similar to that of quoted text in email.
This paper is organized as follows. First, we briefly
explain the historical background of the t-Room project. Then, we introduce the basic concepts that allow
us to feel as if we were actually in the same room. We
then describe our ongoing project for building a prototype system that demonstrates this feeling of being
in the same place and that explores the possibilities of
the concepts. We conclude by mentioning our futureplans and our perspectives.
2. Project backgroundThe core members of the t-Room project are Keiji
Hirata and Yasunori Harada. Up until April 2003,
they had been working independently on various
fields of computer science. Hirata was mainly interested in music information processing and built several music systems, such as those for composition,
arrangement, and performance rendering [1]. Meanwhile, Harada had also been mainly involved in programming languages and user interfaces and had built
many prototype systems. They enjoyed developing
systems that they wanted to develop, in the manner ofmedieval scholars with a patron who could enjoy thefree and easy life of scientific curiosity. Fortunately,
NTT was very broadminded and gave these two freerun of their research fields for more than ten years, forgood or for bad. To some extent, they succeeded inachieving satisfactory results outside the company,that is, in domestic and international academic societies. They built experimental systems and wrote
Vol. 4 No. 12 Dec. 2006

interesting technical papers based on the systems andrepeated the cycle. The systems were dedicated totheir own needs, and the two researchers were theonly users of the systems they developed. The lifetime of each system was inevitably very short.
Although the two were independently involved inbasic research, they came to realize at almost thesame time that they would like to do something not
only to serve the company and society but also to
repay the company’s broadmindedness and patronage. They decided that they had to contribute to thetelecommunications industry, while meeting the challenges of both business and basic research.
They began to discuss intensively how to launch a
new project and arrived at an agreement, which wascharacterized by the following four points. First, theyshould develop systems that they could actually continue to use in their daily lives. This may be a reflection of the fact that the lifetimes of the systems developed previously were short. It also implies development of a system where the developer is an enthusiastic user.
Second, they should concentrate on communication
science simply because it is the mission of their laboratories. They felt that many of the researchers in theCommunication Science Laboratories had beenworking on research topics related neither to communication science nor the telecommunications industry(although they had to admit that this also applied tothem before starting the t-Room project). Hence, they
thought that the personnel allocation of the laboratories was out of balance.
Third, they should develop an application that
could exchange a huge amount of meaningful, beneficial data over a network. From the viewpoint ofNTT’s origin, the construction of network devices,which in a sense involves engineering work, seems to
be a strong point, whereas providing high-level services and developing novel applications do not seema specialty. As a result, the constructed network is not
used effectively, and there are currently many dark
fibers (optical fibers that have been installed to meet
future demand but are currently not in use). To makematters worse, a substantial amount of network traffic is worthless, socially harmful, and even illegal
data.
Fourth, they should take risks and pursue a newfrontier of communication science. They observedthat both young and senior researchers throughout thelaboratories lacked the spirit to meet challenges,
probably because they chose to obtain steady, often
trivial, results and just churn out sufficient technical27

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papers. They both had the experience of changing
research fields two or three times and had made many
attempts in completely different research fields, evenones that were far from mature. Consequently, they
were fortunate in being familiar with working in
unexploited, possibly uninhabited research fields.
In summary, Hirata and Harada firmly decided thatany research theme considered for the new project
should meet the above four criteria. Consequently,
they decided to develop a vision-intensive system that
prompts social interaction [2]. Admittedly, since thestart of the t-Room project, there have been many
twists and turns, but we would like to discuss theseissues later in another article.
Incidentally, we would like to explain the etymology of “t-Room”. Of course, “room” probably needs
no explanation, while the meaning of “t” is a communication environment, medium, or something tofacilitate communication; it encompasses telephone,time-machine, teleportation, total recall, tea, andtobacco.
3. Basics of the feeling of being in the same room
3.1 Rooms of identical layout
To overcome the spatial barrier, we use the simple
approach of building rooms with an identical layout,
including walls of display screens on which users andphysical or virtual objects are all shown at life size.
This enhances the symmetry of awareness (each user
acquires the same kind of awareness information) andthe mutual immersion in each other’s physical space(as many kinds of awareness information as possible
are shared among users).
The basic layout of cameras and displays forachieving symmetry and immersion is shown in Fig.
1. The technique used in the figure was originallyinvented for sharing the drawing surface of a display[3]. Since a liquid crystal display (LCD) inherently
emits polarized light, the polarizing filter in front of
the camera lens effectively cancels out the light fromthe opposite LCD and captures only the light fromreal objects in front of the LCD.
We use this technique to share awareness aroundthe surfaces of the LCDs and to make these surfaces
into a unified input/output device. Here, the size ofthe display is crucial to awareness sharing. Since
wider displays, in general, can show a larger area of auser’s image at life size, they enhance the feeling ofimmersion in each other’s physical space. With thelayout in Fig. 1, the two people can, to some extent,
recognize gestures and recognize when an object is28

Room 1Room 2

Video camera

Polarizing
filter

A

B

Real
LCD
Image

Fig. 1. Basic layout of cameras and displays.

being pointed to and where it is, as long as the act ofpointing is not obscured by other objects. On theother hand, the eye contact recognition provided isstill totally inadequate.
3.2 Playback of recorded activities
To overcome the temporal barrier, we must: 1)
enable a present user to share the awareness of usersthat appear in a cited or quoted fragment and 2) develop an editor that can handle input and output of continuous multistream video and sound data with citation or quotation capability [4]. When we use roomsof an identical layout as unified input/output devices,
activities occurring at a remote room, those in the pastroom, and those in the room where a user is currently
present can all be treated in the same way and thus
overlapped onto each other.
The other distinctive feature of the t-Room is its
metaphor-free structure. When the feeling of being inthe same room holds, a user does not need to change
his/her behavior after entering the t-Room from thatin his/her daily life in the real world. Without using
any metaphor, users can understand objects and activities within the t-Room and manage the t-Roomworkspace in almost the same way as one in the realworld.
In this paper, we often used the phrases “feeling of
being in the same room” and “feel as if we were actually in the same room” to express the phenomenon
provided by a symmetry of awareness and mutual
immersion. We think the sense embodied in thesephrases can be regarded as the overall criterion forwhether a VCS actually succeeds in overcoming spatial and temporal barriers [5].

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4. The t-Room system
Based on the above discussion, we aimed todemonstrate and explore the feeling of being in thesame room by developing a prototype system, calledt-Room [6], as a means to open up a new horizon forcommunication science. The t-Room system isdesigned as simply as possible to meet the demandsof various styles of group activities that might consistof meetings among several people sitting around atable, a lecture by a professor with many students listening, or a casual meeting such as those that takeplace in hallways and cafeterias.
4.1 Hardware design
The hardware design of the current t-Room system
is shown in Fig. 2. A single t-Room consists of six
modules (called monoliths) arranged on six sides ofan octagon and a worktable at the center containing
built-in LCD displays. The 40-inch LCD panels (resolution: 1280 × 768 (WXGA)) should be placedalong a polygon to create the feeling of being in thesame room. Within the t-Room, LCD panels can bearranged in parallel, while such a layout is impossible
in conventional VCSs because the parallel arrangement of LCD panels usually causes visual howling.
When the t-Room systems were first built about ayear and a half ago, there were seven monolith modules arranged octagonally. However, this number
often caused users to feel as if they were locked inside
the room, so we removed one. This eliminated theshut-in feeling while completely preserving the feeling of being in the same room.
We installed two identical t-Rooms in the cities ofAtsugi and Kyoto, which are approximately 400 kmapart. A commercially available 100-Mbit/s opticalfiber line (i.e., fiber to the home (FTTH)) connects
the two rooms. Currently, video data is transmitted by
Motion JPEG (standard set by the Joint Photographic
Experts Group) on TCP/IP (transmission control protocol, Internet protocol), and a single video cameratransmits data at 200–500 kbytes per second. Audio
data is transmitted by PCM (pulse code modulation)
on UDP/IP (user datagram protocol, Internet protocol), which requires a bandwidth of about 1 Mbyte/s.
The total bandwidth required is about 4–8 Mbyte/s.
The actual measured network delay for video datatransmission between Atsugi and Kyoto is around
0.7–0.8 s in normal operating conditions. So far, morethan 250 people, including visitors, have used the tRoom.
4.2 Gaze
One situation where gaze communication seems towork well is shown in Fig. 3. The geometrical relationships observed in Fig. 3 are illustrated in Fig. 4,
which shows people’s positions in gaze communica-

Fig. 3. Gaze communication.
Monolith

2.2 m

1.08 mVideo
camerahole

1.08 mThe other side’s t-Room

Gaze
B

2.6 m

Image

A

Center worktable

1.15

The t-Room shown in Fig. 30.45 mReal

Monolith

40" LCD
Loud panel
speaker

20" LCD
panel × 4

Front view

Top view (6 monoliths)

Fig. 2. Hardware design of t-Room system.

Vol. 4 No. 12 Dec. 2006

LCD panel
CameraFig. 4. Geometrical relationships.

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tion, gaze directions, and camera angles. In the tRoom on the left-hand side of Fig. 4, person B looks
forward and to her right, and the camera captures her
image from front-on. Due to the Mona Lisa effect,
B’s image in the t-Room on the right-hand side looks
too far to the side. The Mona Lisa effect is a cognitive
phenomenon as follows: when a viewer looks at aperson displayed on a screen looking at the front, theviewer feels that the person always appears to follow
the viewer with his/her gaze, wherever the viewer
stands. The same phenomenon occurs for A’s image
as seen by B.
Moreover, since the video cameras are positioned
just above the 40-inch LCD panels, they cannot avoid
capturing images of users in front of the opposite
LCD panels at a downward angle (2.6 m ahead andabout 25 cm down, i.e., a gradient of about –0.1),
which also degrades gaze communication [7]. However, even if a camera could be placed just between
two LCD panels that were next to each other at the
middle height, occlusion would occur due to users
walking around inside the t-Room. We think that thistype of occlusion is more problematic, so we placed
the cameras above the LCDs as close to their upperside as possible.
4.3 Recording and playback
4.3.1 Sharing awarenessA snapshot of a playback in which three t-Roomspaces are overlapped is shown in Fig. 5. Persons A
and C are present, while person B was present eightmonths ago: A is present at location 1, while B and C
were/are at location 2, respectively. Here, A and C
first look at B’s playback image and then look in thesame direction as B to discover what B saw at thetime of recording. Since the t-Room always records
all of the activities that occur within it, A and C candiscover the object that B was looking at by following the end point of B’s gaze. As a result, A and C
successfully share B’s workspace awareness.
The action of C pointing somewhere at B’s image ata certain time during playback plays the role of a citation. That is, the capability of spatial and temporalciting of video and audio data is achieved in a quite
natural way by using the t-Room as a unified
input/output device. For example, at a certain
moment, person C pauses the playback of B’s action
and adds some comments to what B just said. Of
course, person A can do this as well. Note that in thet-Room, actions by A and C, such as pausing andadding, are also all recorded, which facilitates further
citation and quotation by someone else. Unfortunately, the current implementation can only support playback with one level of citation.
The current t-Room system fixes the order of overlapping images and the alpha channel value (transparency ratio); present images with an alpha channel
value of 0.5 come in front of those in the past. Therefore, users in the present see partially transparent
recorded images. The order of overlapping and theindividual alpha channel values may be changed,
depending on the style of activity and/or demand.
4.3.2 Snapshot
If the local person B points at a component of thepersonal computer (PC) on the worktable, remoteperson A can naturally see what B is pointing at (Case
1 in Fig. 6). However, in the reverse situation (Case 2

Case 1
Person A is present at location 1

B’s finger

Worktable display

PC

Person B was previously present at location 2

Remote

Local

Image of PC

Case 2

Image of A’s finger
A’s finger
PC

Person C is present at location 2

Fig. 5. Playback with recorded and remote scenes.

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RemoteLocal

Fig. 6. PC hides the remote user’s finger.

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in Fig. 6), in which A points at a component in animage displayed on the remote worktable, B cannot
see what A is pointing at because the scene on the
remote worktable is correctly displayed at life size on
the local worktable, so the PC on the local worktablehides the displayed image.
Through practical usage over several months, wefound that the snapshot capability was useful for coping with this difficulty. Snapshots are also regarded asa special case of a playback (i.e., instantaneous playback). A scene with a snapshot shared by two people,
A and B, is shown in Fig. 7. A snapshot of a broken
PC placed on the center worktable is taken by a local
camera and displayed on identical LCD panels inboth the local and remote t-Rooms. The two people inthe different t-Rooms can correctly recognize which
component the other person is referring to due to thesymmetry of awareness along with the feeling of
being in the same room.

ken PC with the help of the instructor in a remote tRoom. The instructor did not watch. The pair of
instructor and repairer was assigned three subtasks:
replace the power supply unit, the hard disk drive, andoptical disk drive. Three conditions were set up as
described below.
C1 (Conventional VCS): The repairer sees the
instructor shown on the opposite LCD panel in frontof him/her, while the instructor can see only theimage captured by a WebCam that the repairer holds
in his/her hand.
C2 (t-Room with self-reflection image): This condition corresponds to a basic function level of the tRoom, which is considered a baseline.
C3 (C2 and snapshot): We introduced the snapshot
because it is a special case of recording and playback
capability. Since an experiment properly designed forrecording and playback capability would take a lot oftime, we focused on a short time period and used asnapshot.

5. Preliminary experiment
5.1 Outline
As a step towards demonstrating the feeling of
being in the same room, we conducted a preliminary
experiment to examine the advantages and disadvantages of the t-Room compared with a conventional
VCS. Eleven adults in their 20s and 30s participated;
all of them were novice PC users who had performed
simple tasks with a PC but had never repaired one. In
addition, a subject who played the role of an instructor participated; he had been a lecturer in PC usage at
a technical college for two years. In turn, each novice
PC user in the local t-Room was asked to repair a bro-

Person A present in remote t-RoomAlso displayed in remote t-Room

Person B

5.2 Results (feedback from participants)
All repairers successfully complete the three subtasks, taking from 20 to 70 minutes per task. Overall,
9 out of the 11 repairers reported that C3 was the easiest of the three conditions to work in, and the other 2
said C1 was. 10 of the repairers said that the easiest
subtask was replacing the power supply unit followedby the hard disk drive and optical disk drive.
In C1, repairers frequently mentioned the usabilityof a handy WebCam and whether or not repairers
could understand the instructor (T)’s instructions.
One repairer (R1) found C2 easier because R1 and a
PC on the worktable were entirely captured by surrounding cameras from a fixed viewpoint, and there
was no need for R1 to control the viewpoint. Anotherrepairer (R2) pointed out that in C2, it was difficult tosee T’s finger shown on the worktable and hence todetermine what it pointed at. R2 also said that the gap
between T’s fingertip and the target being pointed atby it just confused him. In C3, five repairers reported
that using a snapshot improved certainty; it was likeusing a blackboard. The snapshot enabled R3 to easily understand what T was saying. R4 was happy thatthe snapshot enabled T to understand what he said
and vice versa.
6. Conclusion

Fig. 7. Pointing at component on snapshot.

Vol. 4 No. 12 Dec. 2006

The t-Room is a remote collaboration system thatprovides symmetry of awareness and immersion ineach other’s physical space that allows users in sepa31

Selected Papers

rate t-Rooms to feel as if they were actually in thesame room, unlike a conventional videoconferencing
system. In launching the t-Room project, we had four
goals: to improve our daily lives, contribute to communication science, exchange a huge amount of
meaningful, beneficial data, and take risks in basic
research. We think that these four points are still relevant and that the t-Room project could lead to theirsuccessful achievement.
Provisional results for a preliminary experimentwith the t-Room, in which a novice user repaired a PC
while consulting a remote instructor, imply that the tRoom has more potential to reproduce reality andawareness in remote collaborations (the feeling of
being in the same room) than is possible with conventional videoconferencing systems.
We think that future work should include developing full-fledged recording and playback facilities,
providing sound capability that supports the feelingof being in the same room, building a large, multilocation t-Room, conducting further experiments andevaluations, and designing and implementing flexible, scalable middleware for a variety of applications.
We demonstrated this system at NTT Communication Science Laboratories Open House 2005 (June2005), and many visitors were highly impressed by
the feeling of being in the same room. In December
2005, we launched the official “t-Room” website [8].
This site is packed with all sorts of information,
including a description of the technology behind tRoom and an 11-minute demonstration video. You
are invited to take a look.

32

Finally, we do not want readers to underestimate
the potential of the t-Room. We are developing the tRoom as a future form of telephone service. Toward
the future phone, it will be possible to provide a wide
variety of communication services while giving thefeeling of being in the same room with people at different places and different times, thus creating a newsocial interaction style with large displays. In thissense, we think that calling our system a “videoconferencing system” would be inappropriate becausethat would give people a false mental image that fails
to convey its futuristic abilities. We prefer to avoid
using that term.
References
[1]

[2]
[3]
[4]

[5]

[6]

[7]

[8]

K. Hirata, “Musical Knowledge Programming for a New Form ofMusic Distribution,” NTT Technical Review, Vol. 2, No. 12, pp. 611, 2004.
D. A. Norman, “Emotional Design: Why We Love (or Hate) Everyday Things,” Basic Books, 2005.
J. C. Tang and S. L. Minneman, “VideoDraw: A Video Interface forCollaborative Drawing,” Proc. of CHI ‘90, pp. 313-320.
T. Takada and Y. Harada, “Citation-Capable Video Messages: Overcoming the Time Differences without Losing Interactivity,” Proc. ofInformation Spaces and Visual Interfaces 2000, pp. 31-38.
Y. Harada, “Communication with the feeling of being in the sameroom,” Proc. of Workshop on Interactive System and Software ‘98 (inJapanese).
K. Hirata, Y. Harada, T. Ohno, T. Yamada, J. Yamato, and Y. Yanagisawa, “t-Room: Telecollaborative Room for Everyday Interaction,”
Proc. of The 66th IPSJ Annual Convention, 4B-3, 2004.
L. Mühlenbach, M. Böcker, and A. Prussog, “Telepresence in Videocommunications: A Study on Stereoscopy and Individual Eye Contact,” Human Factors, Vol. 37(2), pp. 290-305, 1995.
www.mirainodenwa.com (in Japanese).

NTT Technical Review

Selected Papers

Keiji Hirata

Shigemi Aoyagi

Senior Research Engineer, Computer Scientist,
Principal Engineer of Media Interaction Principle Open Laboratory, NTT Communication Science Laboratories.
He received the B.E. degree in metal engineering, M.E. degree in information engineering, andD.Eng. degree in information engineering fromthe University of Tokyo, Tokyo, in 1981, 1983,
and 1987, respectively. He joined NTT Basic
Research Laboratories in 1987. He spent 1990 to
1993 at the Institute for New Generation Computer Technology (ICOT), where he engaged in
R&D of parallel inference machines. In 1999, hemoved to NTT Communication Science Laboratories. He was promoted to Distinguished
Researcher in 2001. His research interests
include musical knowledge programming andhuman-computer interaction. He received the
Takahashi Award for a paper presented at theannual convention of the Japan Society for Software Science and Technology in 1987 and the
IPSJ Best Paper Award from the Information
Processing Society of Japan (IPSJ) in 2001. Heco-edited and wrote the book chapter “MusicalKnowledge Representation on a Computer” inthe book “The World of Computers and Music:
Foundations to Frontiers” (in Japanese) in 1998
and co-translated the book “Computer Music
Tutorial” by Curtis Roads in 2001. He is a member of IPSJ, the Japanese Society for Artificial
Intelligence, and the Japan Society for Software
Science and Technology (JSSST).

Research Scientist, Media Interaction Principle
Open Laboratory, NTT Communication Science
Laboratories.
He received the B.E. and M.E. degrees in information science from Tokyo Institute of Technology, Tokyo, in 1988 and 1990, respectively. He
joined NTT in 1990. His current research interests include parallel processing, distributed algorithms, image understanding, object recognition,and distributed systems for multimedia content.
He is a member of the Institute of Electronics,
Information and Communication Engineers(IEICE) of Japan, IPSJ, and JSSST.

Yoshinari Shirai
Researcher, Ambient Semantics ResearchGroup, Innovative Communication Laboratory,
NTT Communication Science Laboratories.
He received the B.A. degree in environmental
information and M.E. degree in media and governance from Keio University, Tokyo, in 1998
and 2000, respectively. He joined NTT Communication Science Laboratories in 2000. His
research interests include ubiquitous computing
and interaction design. He is a member of ACM,IPSJ and the Human Interface Society of Japan.

Yasunori Harada
Senior Research Engineer, Chief Technology
Officer of Media Interaction Principle Open Laboratory, NTT Communication Science Laboratories.
He received the B.S. degree in applied physics,
M.E. degree in information engineering, andDr.Eng degree in information engineering from
Hokkaido University, Hokkaido, in 1987, 1989,
and 1992, respectively. He joined NTT Basic
Research Laboratories in 1992. He spent 1998 to2001 at PRESTO-JST (Precursory Research for
Embryonic Science and Technology, Japan Science and Technology Agency). His researchinterests include visual language and object-oriented programming.

Naomi Yamashita
Ambient Semantics Research Group, Innovative Communication Laboratory, NTT Communication Science Laboratories.
She received the B.E. and M.I. degrees inapplied mathematics and physics and the Ph.D.
degree in informatics from Kyoto University,
Kyoto, in 1999, 2001, and 2006, respectively.
She joined NTT in 2001. She is interested incomputer supported collaborative work andinteraction analysis.

Toshihiro Takada
Senior Researcher, Media Interaction Principle
Open Laboratory, NTT Communication Science
Laboratories.
He received the B.E. and M.E. degrees in information science from Tokyo Institute of Technology, Tokyo, in 1986 and 1988, respectively. He
joined NTT in 1988. His research interests are in
networked information systems, networked computation, real-space computing, and human-computer interaction. He is a member of the Association for Computing Machinery (ACM), JPSJ,JSSST, and the Human Interface Society ofJapan.

Vol. 4 No. 12 Dec. 2006

Junji Yamato
Senior Research Scientist, Supervisor, Group
Leader of Recognition Research Group, MediaInformation Laboratory, NTT Communication
Science Laboratories.
He received the B.E, M.E., and Ph.D. degrees
in precision machinery engineering from the
University of Tokyo, Tokyo, in 1988, 1990, and2001, respectively, and the S.M. degree in electrical engineering and computer science from the
Massachusetts Institute of Technology in 1998.
He joined NTT Human Interface Laboratories in1990. His research interests are in machine computer vision, human-computer interaction, androbotics. He is a member of IEEE, ACM, IEICE,
and the Robotics Society of Japan.

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