Optoelectronic Technology Trends
1. Introduction frequency waves) of millimeter wave wireless. The wavelength range
The OITDA establishes an Optoelectronic Technology Trend has been determined due to dispersions or losses of ﬁber in the near-
Research Committee every ﬁscal year as part of the optoelectronic infrared range for optical communication, and component development
technology trends survey project, in order to investigate and analyze in each wavelength band is in progress depending on factors such as
new movements in optoelectronics-related technology domestically transmission distance, speed, purpose, etc. The progress situations of
and abroad. This ﬁscal year, working groups were organized to address the trunk line system, the metro system, and the access system slightly
and investigate the eight ﬁelds described below (the study on medical vary every ﬁscal year. Where the focal point of the previous ﬁscal
technology in the optical industry will be conducted for a limited year s investigation was multi-level photonic devices that contribute
period). The results will be presented at the optoelectronic technology to update of communication records for the trunk line system, this
trends seminar at the InterOpto 2010 exhibition scheduled to be held ﬁscal year s investigations focused on modules associated with
on October 1, 2010. Also, 17 articles on the latest technology trends standardization and speed-up of Ethernet systems. A continuously
in topics on each ﬁeld were presented in Technology Trends on the investigated topic is the speed-up of optical sources and Si photonics;
OITDA web news site, OptoNews. photoreceptors and modulators were investigated last ﬁscal year,
With regard to the overseas ﬁeld survey of trends in optoelectronic whereas this ﬁscal year, light-emitting devices and integration devices
technology, investigators were dispatched to WC2009 (Munich) in were investigated. In the visible and ultraviolet range, there has been
September and to WT2010 (Spain) in January to investigate medical progress in achieving high-output in the deep ultraviolet range, and
related trends, and trends in optical materials and devices. lengthening of long waves in nitride-based semiconductor devices.
In addition, the project was subsidized by JKA through its Promotion This ﬁscal year s breakthrough is achievement of green color in a
funds from KEIRIN RACE. nitride-based semiconductor laser. Blue-violet ~ blue semiconductor
lasers, ultraviolet LEDs, and GaN-based surface-emitting lasers are
2. Optical Devices and Materials (Working Group 1) continuously investigated topics; white LED lighting and organic EL
As it does every ﬁscal year, the Optical Devices and Materials lighting were investigated as topic items from the recently important
Working Group investigated modules and applications, mainly devices, aspects of energy and environmental conservation.
in the wavelength range of several 100 m to near 200nm. Table 1 In addition to last year s efforts on achievement of higher performance
shows the technology investigation items, classiﬁed by wavelength in basic technologies and devices for new applications, a lot of device
axis. development and module development work for standardization and
The terahertz band is the extended wavelength range between radio energy conservation was seen this ﬁscal year. Each investigation item
and optical waves, and development is progressing for higher frequency for terahertz band, near-infrared (for optical communications), and
radio waves and longer optical waves (lower frequency waves). Until visible and ultraviolet range is summarized below.
last year, the investigations were done in the order of: light-emitting
devices light-receiving devices equipment, and this year light- 2.1 Terahertz Band
emitting devices were investigated after an interval of 3 years. Since Since terahertz band is located between light and radio waves and
the applications contain properties of both radio and optical waves, has physical properties of both waves, many possibilities were
many possibilities are being investigated, and this ﬁscal year, terahertz investigated. This ﬁscal year, high-speed wireless applications were
wireless was examined in terms of increasing the speed (higher investigated for extension of the millimeter wave. In the existing
Table 1 the technology investigation items
17 Annual Technical Report
millimeter wave (60~80GHz), the maximum transmission speed is systems and structures are being explored for Si-based light emitters.
several Gb/s, whereas in terahertz waves, a transmission speed of In an attempt to emit light in shorter wavelengths than the Si bandgap
10~100Gb/s is theoretically possible. However, due to increased wavelength, EL luminescence using nanostructures or Si light emitting
atmospheric attenuation, the transmission distance is dramatically diodes with ultrathin membrane that uses quantum effects are being
shortened. As terahertz wireless generators, several methods are being reported. There are also reports of growth of Si/GaPN/Si types being
investigated from radio aspects and optics aspects, and actual cases of achieved by using thin nitrogen series in an attempt to integrate Si and
transmissions have been reported in 1000Hz~several THz at III-V group light emitters using epitaxial, and light emitting diodes
approximately 1~10Gb/s for several km~10km. With the use of using GaPN/GaAsN-SQW on Si. On the other hand, investigations are
electronic devices in radio wave generators, there has been progress being done to make the band structure similar to that of a direct
in the achievement of higher frequency and higher output of oscillatory transition model, by applying stretching strain to Ge from the
frequency, with reports of fundamental wave oscillation being up to 1 wavelength length side. Improvements in luminescence efﬁciency
THz in resonant tunneling diodes, and current gain cutoff frequency brought about with the use of SiGe/FeSi2/SiGe are being investigated.
and maximum oscillatory frequency being approximately 1 THz in As for integration, investigations are being done on monolithic
HBT and HEMT. Investigations have also recently begun on Si-CMOS, integration mainly of materials such as photoreceptors, modulators,
possibly due to the large existing market for millimeter wave. On the wavelength ﬁlters etc., that can coexist with the Si-CMOS process.
other hand, THz wave oscillation using quantum cascade laser is being
investigated in optic wave generators. In the existing quantum cascade 2.3 Visible and ultraviolet ranges
lasers, room temperature oscillation is possible at 3.1~10.6 m, however, In visible and ultraviolet ranges, progress is being made in
room temperature oscillation in terahertz band has not yet been achievement of output-power improvement of light emitting diodes,
achieved. In optic waves, longer wavelengths (lower frequencies) are and expansion of wavelength range of nitride-based semiconductor
more difﬁcult, and up to now the maximum oscillation temperature is diodes. The previous wavelength of nitride-based semiconductor diode
186K at 3THz. Investigations in active layer structure and factor was less than 500nm blue-green color ﬁxing, however, this ﬁscal year
analysis for room temperature oscillation are in progress. a new semipolar substrate (20-21) surface was used to achieve 531nm
at room temperature pulse, and 520nm at room temperature continuous
2.2 Near-infrared range (Wavelength range for optical communication operation. Also, room temperature continuous oscillation of 515 nm
systems) was achieved using the existing (0001) C surface, and semiconductor
There have been advances in wavelength range of optical diodes achieved green, a range previously not entered. In pure blue
communications systems in terms of increase in communication color, horizontal single mode nitride-based semiconductor lasers (pulse
capacity, spread and higher speeds of Ethernet systems in networks, 120mW, continuous 60mW) were also developed, in addition to the
and smaller size and energy conservation in optic transceivers used existing horizontal multimode. A shift from the short wavelength of
for interface. In the Ethernet systems, 10 Gb Ethernet (10 GbE) was 660nm for DVDs to 638nm with improved visual sensitivity had already
introduced in the year 2002, and this ﬁscal year the ﬁnal speciﬁcations been achieved in red waves, and this ﬁscal year the 3 primary colors
for 40/100 GbE have been decided and are awaiting approval. The of light (blue, green and red) were achieved by semiconductor laser.
main difference between the systems in terms of transmission is that On the other hand, long term reliability can now be gained in the
up to 10GbE was mainly serial transmission, whereas in 40/100 GbE existing blue-violet nitride-based semiconductor lasers, even during
the transmission would be parallel (4, 10 lanes). Therefore, in the high power output of 500mW, because the speed of optical disk for
optical source, speedup of 25 Gbit/s in 1.3 m band for 100 GbE (4 recording has been increased. Towards new applications, investigations
lanes) is being aimed for along with lower cost. There is progress in on surface luminescence laser are in progress, where photonic crystal
power conservation, along with investigations on speed-up of direct type and inclined mirror type were realized last ﬁscal year, and vertical
modulation laser (10 25 Git/s) for the 10km version, and changes resonator surface-emitting laser that uses the top and bottom DBR
in wavelength band of external modulation integration laser of trunk mirror was achieved this ﬁscal year. There has been a growing interest
line system (1.55 1.3 m band) in the 40km version. In optical in illumination in terms of energy and environmental conservation. In
transceivers, power conservation and miniaturization of common white LED lighting that uses a combination of nitride-based light
industrial speciﬁcations is being aimed for, in addition to efforts to emitting diode (LED) and luminescent materials, properties (general
increase in number of ports for transmission devices. For this, it was color rendering index: 92, luminescence efﬁciency: 62lm/W, total
planned to achieve miniaturization and power conservation, moving luminous ﬂux: 500lm) that are superior to light bulb type ﬂuorescent
from 300 pin X2 XFP SEP + by removing from the module lamps have been developed. On the other hand an LED is a point light
the CDR which contains serial/parallel conversion IC and 3R functions. source, whereas an organic EL is a two dimensional light source. During
Furthermore, low-power integrated two-way IC in the latest SFP+ for initial development, efﬁciency was low and there were issues with
10km, and power conservation using un-cooled operations and high reliability, but with the development of phosphorescence luminescence
temperature operations of EA/DFB optical sources in SFP+ for 40 km materials and peripheral technologies, properties similar to those of
are being developed. Modulator integration and miniaturization in terms ﬂuorescent lamps have been obtained. Though presently there are some
of mounting to modules is under progress for variable wavelength differences in LED lighting and organic EL, their practical
optical sources, and advances are being made in mounting to 38 pin implementation is expected to progress in the future in terms cost (cost
butterﬂy, TOSA and XFP using MZ model of modulator that is of apparatus: ¥/brightness: 1m), purpose, design etc., along with
advantageous in a wide wavelength range. Moreover, monolithic improved elemental characteristics.
integration of InP type ring resonator with external resonator that uses
silicon waveguide is being investigated, in a recent attempt to 3. Optical Communication Networks (Working Group 2)
miniaturize the variable wavelength optical source itself. Many material The number of domestic FTTH (Fiber to the home) contracts reached
Annual Technical Report 18
Optoelectronic Technology Trends
16 million lines in June 2009, accounting for more than 50% of the remarkable progress in R&D related to speed-up of transmission speed
domestic broadband contracts (31 million). In access networks, there to 100 Gb/s per wavelength. Coherent reception based on digital signal
has been a major shift to optical ﬁber communications, from copper processing has brought the long distance transmission system, having
line communications such as DSL (Digital Subscriber Line: up to100 Gb/s x 100 waves, closer to reality. Also, mounted components
approximately 11 new million subscribers) and CATV (Cable Television: are being standardized in accordance with the industry group OIF
approximately 4 million subscribers). This means that Japan has shifted (Optical Internetworking Forum). Investigations on further speed-up
to a period when optical communication networks now serve as the and increased capacity of wireless communication systems and similar
foundation of Japan s telecommunications infrastructure, both in name complex multi-valued modulation methods are also being initiated.
and in reality. The domestic internet trafﬁc volume increased by 40% In photonic nodes, ROADM (Reconﬁgurable OADM) and optical
times in the past year, and domestic download trafﬁc volume is branching insertion nodes in ring parts are being introduced. Multi-
estimated to have surpassed 1 terabit per second (1 Tb/s) in 2009. degree ROADM technology that enables optical interconnection
The development of this information-communication society has between multiple rings is being developed. This technology is expected
been supported by technology innovations in the optical communications to control electricity consumption by reducing the installation surface
network. Dr. Kao, a recipient of the 2009 Nobel Prize in Physics, area and the number of network devices. The development of element
predicted the prospects of optical ﬁber communications. Based on his technology as a future technology for optical burst/optical packet
predictions, low loss optical ﬁber was developed in 1970. Since then, switches is also advancing.
cutting-edge research & development and implementation work in this With regard to optical networking, technology is being developed
ﬁeld have been going on in Japan. Starting with conversions to ﬁber that integrates and controls optical path conversion having long
optics in long distance mainline and trunk lines in the 1980s, and distance/high capacity, with packet networking that efﬁciently
introduction of metro 10 Gb/s optical ring nets in the 1990s, in the multiplexes packet trafﬁc coming from users. This ﬁscal year,
2000s the system has evolved to ﬁber optic broadband network investigations on control models such as power conservation network
conﬁgurations such as core/metro/access. The following systems have design theory, methods of fault recovery between layers, impairment
been introduced in each of the networks; dense wavelength division routing that secures reachability of optical signals (method of
multiplexing (DWDM) system that links two ultra-long distance points establishing paths after considering transmission properties of individual
using repeated optical ampliﬁcation relays, DWDM ring network optical paths), etc have gained momentum.
system constructed with OADM nodes (Optical Add/Drop Multiplexer) As for optical access, 1 Gb/s class FTTH is being launched, and
that carries out optical branching and insertion & ampliﬁcation, and R&D on next generation optical access systems is being actively
PON (Passive Optical Network) system that carries out optical pursued in terms of high capacity and higher speed for achieving high-
branching (down) and optical time division multiplexing (up). There deﬁnition image distribution, etc. We see a move to full scale technology
have been dramatic cost reductions with the introduction of such development for 10G-EPON (10 G Ethernet PON) that saw its
systems that are based on technological innovations such as standardization completed in September 2009, and technological
multiwavelength optical batch ampliﬁcation and optical switches. For developments in next-generation optical access systems applied in
instance, the main advantage of the existing practical use DWDM multilevel modulation technology and signal processing technology.
system is that it bundles and sends 10 Gb/s signals at 40~80 wavelength, With regards to the optical LAN/interconnect ﬁeld, technological
and the system capacity of each ﬁber in the core net and metro net is developments in 40 Gb/s and 100 Gb/s Ethernet that were scheduled
between 0.4~0.8 Tb/s. to be standardized by June 2010 are reaching their climax. Moreover,
However, R&D on such optical communication network technologies maximum capacity of backbone routers/switches has already crossed
is expected to reach a turning point as we enter the 2010s decade. Just 1 Tb/s per unit, and 4~10 Tb/s router/switches are expected to be
a simple transmission system of switching a light ON/OFF operates introduced from 2010 onwards. For this, the focus is on ultra-high
at 10 Gb/s per wavelength, and wavelength multiplexing per ﬁber is speed-up with channel bit rate of ≥ 20 Gb/s, and technology related to
about 100 waves, reaching the physical limit of each optical ﬁber. With energy saving optical devices/circuits/assemblies with < 10mW/
the introduction of optics technology, there has been a rapid speed-up Gb/s.
of Ethernet LAN (Local Area Network), and 100 Gb/s Ethernet is In the optical ﬁber ﬁeld, as FTTH is being used increasingly, there
expected to get standardized in the year 2010. LAN optical technology are advances in technology development of low-bending-loss optical
is expected to foray into the 100G era, ahead of WANs (Wide Area ﬁbers used in premise/access systems that help in achieving improved
Networks). In other words, the role of accelerating the speed-up process degree of freedom for wiring and equipment miniaturization, and skill-
of optics technology is shifting from WAN to LAN. Furthermore, the less line opening construction. Investigations on multicore ﬁbers have
focus is now beginning to shift towards internal parts of equipment also been initiated, aiming for breakthroughs in the physical limits of
(optical interconnection). ﬁber optics capacity in trunk line systems.
Based on this background, working group 2 summarized this ﬁscal
year s trends in optical communication network technology, with 4. Optical Memory and Information Processing (Working
consideration given to the following 6 ﬁelds. Group 3)
1. Trunk optical transmission systems The market conditions concerning optical memory in FY 2009 are
2. Photonic nodes becoming increasingly unclear. Coupled with the spread of network
3. Optical networking distribution of contents, and achievement of high capacity low-cost
4. Access network semiconductor memory, the marketability of optical memory came
5. Optic LAN/interconnect under threat. On the other hand, 3D displays, higher deﬁnition cameras
6. Optical ﬁbers and contents needing large capacity optical memory are being launched.
Concerning trunk line optical transmission systems, there has been Moreover, construction of archive systems using optical memory is
19 Annual Technical Report
being investigated, with the purpose of energy conservation. come up with the eco point system and the approaching switch to
Technological developments in optical information processing digital broadcasts in 2011. There has been rapid growth in demand for
technology are not restricted to the existing memory system or search low-cost goods, due to the decrease in demand from U.S. and expansion
systems, but have spread to other ﬁelds such as information security, of emerging markets such as China and India. Simultaneously, there
measurement, and manufacturing. is a global demand for a switchover to a low-energy society, with a
Through a survey of technological trends in this ﬁeld this ﬁscal year, top priority being reduction in electricity consumed by displays.
development trends for the present and next-generation optical memory Regulations are being reinforced with speciﬁc energy conservation
systems were investigated and their differences and advantages targets, such as Energy Star, EuP, and amendment of the Act on the
compared with those of other memory technologies were summarized. Rational Use of Energy (FY 2010). There is an increasing need for
Moreover, new developments in the ﬁeld of optical information cost reduction technology, power consumption reduction technology,
processing were investigated. The investigation points are summarized and resource saving technology. Moreover, 3D is a popular topic at
below. national and international trade exhibitions, and many products are
planned to be launched, making 2010 the dawn of the new 3D
4.1 Development of Blue Optical Disc market.
The speciﬁcations for Blu-ray Disc (BD) standards for 3D content
were released in FY 2009, and the demand for optical memory with 5.1 Electronic Display Devices
larger capacity has been growing. In response to this situation, 5.1.1 Liquid Crystal Displays (LCDs)
technology developments in multilayer technology that further improves This year, the broad trend is toward 3D images and ﬂexibility, and
the capacity of the existing system (BD) were investigated. This ﬁscal both trends are opening up new application ﬁelds for LCDs. Since
year, there were advances in multilayer technology, particularly in liquid crystal is a polarization control device and not a light emitting
rewritable optical disks (3 layer 100 GB) and recordable disks (10 element, 3D display is a perfectly suitable ﬁeld of application. With
layer 320 GB). In ROM, a 16 layer 400 GB disk has already been regards to ﬂexibility, there is progress in properties of organic and
announced, and a capacity of over 100 GB in all existing optical oxide semiconductors, and ﬂexible displays are being developed using
memory shapes using multilayer technology has been demonstrated. plastic board. Having liquidity properties and voltage driving force,
Investigations were made on trends of technologies required to liquid crystals are a suitable display element for ﬂexible displays.
differentiate vs. other memory technologies, in terms of archival uses, Moreover, display mode and structure that further improves the optical
broadcast uses, and energy conservation. Optical disks are strong in transmittance of backlight was developed as a step for prevention of
features such as long life, portability and energy conservation, but we global warming.
found that increasing their capacity and transfer speeds are major issues
for their adoption in archival uses etc. vs. magnetic disks and magnetic 5.1.2 Plasma Display Panels (PDPs)
tapes. PDP panels are being manufactured by just 3 companies in the world:
1 Japanese and 2 Korean companies. With the continuous increase in
4.2 Next-Generation Large-Capacity Technology the demand for panels, expansion and operation of efﬁcient new lines
A survey was done on the development of next generation large is being initiated. Moreover, supply of new panels to is also starting
capacity technology, and progress made on near-ﬁeld optical disks, in China and India. After the Lehman shock, display prices continued
ultra-resolution disks, hologram, 3D bit by bit recording, and elemental to decline, leading to further advancements in low cost technology.
technologies, such as signal processing technology, server technology There have been continuous developments in low power technology.
and components, used for achieving large capacity in the above- Owing to the demand for high deﬁnition products such as super high-
mentioned ﬁelds. For the ﬁrst time, reading of contents using super- deﬁnition television (4k x 8k resolution) and digital cinema (2k x 4k),
resolution disks (50 GB (BD x 2), twice the speed), and 34 layer/204 a 2k x 4k panel was prototyped and a 3DPDP was exhibited.
GB using micro-reﬂector having just one layer of bit by bit volumetric
records, were achieved this ﬁscal year, thereby conﬁrming steps forward 5.1.3 Organic Electro-Luminescence
in the appearance of technologies moving towards practical The expected market for organic EL television has not yet been
applications. established due to delays in ﬁnding solutions for issues such as
increasing the size, backplane, lower cost, etc. Furthermore, EL cost
4.3 Optical Information Processing reduction is lagging far behind liquid crystal displays and PDP.
As research topics on optical information processing that has started However, in small size displays of up to 3 inches, its market share is
to spread across various ﬁelds, information security technology, 3D gradually growing in ﬁelds such as mobile phones and MP3 players.
information technology, and their respective technology trends including As for the backplane issue, the solution may lie in oxide semiconductors.
new trends, were investigated. Their representative examples were; Moreover, in spectacles-based 3D television, a refresh rate of 240 Hz
photonic smart media and hierarchical memory based on near-ﬁeld or more may be required in the future, and the winds may be favorable
optical interaction, super-high speed two-dimensional optical for organic EL displays due to their fast response speed.
information retrieval system that uses hologram, and technology trends
in digital optics. Presently, their development is primarily academic, 5.1.4 Field Emission Display (FED) and Micro Electro Mechanical System
and we hope these ﬁelds will evolve into industries. (MEMS)
Active research and development is being done in ﬁeld emission
5. Displays (Working Group 4) display which is equipped with MEMS technology that uses ﬁeld
Amidst the sluggish in the global recession, there has been a sudden emitter array as the electron source. As for the light source, backlight
fall in the prices of displays. At the same time, active demand has also with low environmental burden is being sought for liquid crystal
Annual Technical Report 20
Optoelectronic Technology Trends
display, and there is suddenly much more research on ﬁeld emission given to achieve higher performance CMOS image sensors (high speed,
lamps, in which it is possible to manufacture level surface/atypical wider dynamic range, high sensitivity) and incorporating more functions
light source without using mercury that causes environmental pollution. such as high level functionality (3D measurement and biomedical
In recent years, active R&D has also begun on displays using quantum applications).
dots, and on MEMS displays that display images by using MEMS
micromirrors for optical reﬂection, diffraction and interference 6.2 Disaster-prevention-related information systems for municipalities
phenomena, or by using MEMS optical shutters for optical This ﬁscal year, the trends on disaster prevention information systems
modulation. for municipalities were surveyed. Since only the municipal mayor has
the authority to give evacuation warnings and orders, the tasks of
5.1.5 Electronic paper gathering and managing information for making a decision and means
In electronic paper, electrophoresis is the most popular method when of communicating the announcement are extremely important issues.
it comes to digital book readers. However there are active technological Until now the disaster prevention systems used by the municipalities
developments in other methods such as powder movement method, were independent dedicated systems such as disaster prevention radio
twist ball method, bistable liquid crystal method, electrochromic communication systems, but such systems are greatly affected by of
method, electrowetting method etc. A developmental trend is also seen municipality mergers, and their reconstruction is a major issue. On the
in applied surfaces in terms of all-purpose paper readers, price tags, other hand, with the development of information and communication
POP advertisements etc. technology such as WEB and LAN, and the spread of terrestrial digital
broadcasting and emergency area emails, drastic changes can be
5.1.6 Projection expected over the next few years.
This ﬁscal year, investigations were made on screen technology,
new method optical system technology, light bubble technology, light 6.3 Biometrics (Applications of network cameras and biometrics)
source technology for projectors, and on the latest situation on all types The household broadband penetration rate has passed 60% in Japan.
of projectors (micro projectors, ultra short focus projectors, 3D High bandwidth wireless communications (WiMAX, XGP, LTE, etc.)
projectors, etc.) will be available in 2010. Also, use of netbooks and smartphones etc.
is expected to become more widespread. With the spread of IP cameras,
5.1.7 3-D Display web cameras and mobile phones with cameras, it has become possible
The year 2010 is expected to be the dawn of 3D display , in which to handle large quantities of image data. Therefore, intelligent video
a full blown market for 3D is expected to be established. However, functions that instantly retrieve important information from large
common measurement concepts for three-dimensional display are not quantities of live video using biometrics and image processing
properly formed as yet, and there is a pressing global need to establish technology have gained importance. Reports were made on these
the measurement methods. Investigations were made on measurement applied technologies.
methods for 3D displays, the status of its international standardization,
and the latest situation of various 3D display devices. 6.4 Image Input Devices
Various initiatives are being taken to rectify the problems in single-
5.2 Electronic Display Basic Technology lens reﬂex digital cameras, which have been recently gaining popularity.
The latest situation on improvements made in video quality and The problem in this camera is that image quality gets affected during
color reproduction of displays was surveyed. lens conversion, as dirt sticks to the image sensor (or correctly called
the low-pass ﬁlter), and the latest technologies are being introduced
5.3 Topics to tackle this issue. Moreover, technologies related to new concepts in
The issues in ﬂexible displays, their future prospects, and performance digital camera modules, and dynamic range magniﬁcation technologies
of curved images were taken up as topics. for photographing large subjects having luminescence difference are
6. Human Interface (Working Group 5)
This subcommittee investigated a wide range of trends in the latest 6.5 Ubiquitous Interaction (Universal Web Design)
human interface technologies, from an input device to application The purpose of universal web design is to make web usage easier
technologies. Typically, it conducts an in-house survey on technological for people, including senior citizens and handicapped persons. For
trends in the ﬁelds of image sensor devices, image input device/ this, continuing on the survey done in FY 2007 on technology for
apparatus, disaster prevention-related systems, biometrics, ubiquitous supporting web contents creation, and in FY 2008 on technology for
interaction, and relief/security services. It also added the brain-machine supporting output of contents, this ﬁscal year, technologies to evaluate
interface ﬁeld in its 2-3 year plan. web universal designs were surveyed. A few of the challenges in
evaluation are (1) deﬁnition of evaluation standards, (2) increase in
6.1 Image Sensors objects to be evaluated, (3) methods of displaying evaluation results,
In the IISW (International Image Sensor Workshop), trends on image etc. Investigations were made on evaluation guidelines such as the
sensor devices were explained based on the reports and journals from UWEM 1.2 of EU, construction of evaluation conforming to the WCAG
related associations (ISSCC, The Institute of Image Information and 2.0 standards, summary of JISX 8341-3 revisions, problems in Japan s
Television Engineers, etc.). Development of back-illuminated image web technologies, etc.
sensors is being actively pursued in the backdrop of competition to
miniaturize the image pixels. Sooner or later miniaturization will reach 6.6 Brain Machine Interface
its peak and therefore, apart from imaging, more importance is being In accordance with development of brain function measurement
21 Annual Technical Report
technology in recent years, research and development in technology 7.2 Processing-related technology
called brain machine interface (BMI) has been going on along with Scanner is an essential technology for improving the throughput
the growing understanding of brain functions. BMI is said to be the of laser processing, and high output of lasers for processing is making
ultimate interface that measures and analyses the brain activities, for it indispensable to have high-speed scanning of laser beams.
operations by thought alone . BMI was developed as a means of Investigations were made on technologies that use optical encoders in
communication and environmental control, for patients who lack location sensors by digitally controlling the Galvano scanner, which
physical freedom but can think normally. This document introduces is a digital high-speed scanner that scans mechanically at a high
the basic conﬁguration and user tasks, brain activity measurement speed. Moreover, the multi-prism scanner and KTN scanner that apply
technology which is the main technology, and an example of BMI electro-optic effects, in which prism is electrically scanned, were
(P300 Speller). investigated under electro-optic effect scanners.
6.7 Home security / reliable service (Computerization of healthcare 7.3 Processing Technology
information and social security, and introduction of cards) Until now, welding, the technique for joining metals, was in the
There is growing importance of enhancing medical welfare mainstream as a technology for joining similar materials, but recently,
technology for the aging population, along with individualized medical technologies are being developed that join different materials such as
treatment and medication to match the body s constitution and illness metals with plastics etc. This ﬁscal year, investigations were made on
of individuals. Under the health care system reforms, discussions are junction technology using ultrashort pulses, and junction technology
ongoing to use a single social security card that includes social security using CW laser, junction technology using insert materials. It is now
information, pension book, health insurance information and nursing possible to input heat only around the junction part with precise heat
insurance information. This would be infrastructure to promote effective input control of the laser. Now two pieces of glass can be joined, and
and efﬁcient health care with nursing, rehabilitation, prevention, and different materials can be joined, for example glass with metal, metal
health. Against this backdrop, a survey was done on computerized with plastic (resin), etc.
social security/medical care sectors in developed countries, and a survey
on technologies related to security, optical technology and its application 7.4 Measurement Technologies
examples. Digital holography is a technology that reproduces numerical values
in a computer and uses imaging elements such as CCD to digitize
7. Laser Processing and Optical Measurement (Working recorded images, instead of using conventional photographic plates.
Group 6) It is expected to be used in various applications since its high speed
This ﬁscal year, the survey of processing and measurement included processing can provide digitally obtained information to distant places,
ﬁber lasers, hybrid lasers and chirped pulse oscillators as optical and the image developing process is not required.
technology for manufacturing; scanners as processing-related A Super high speed photography camera in which the photographing
technology; bonding technology using various lasers as processing speed can be 1 million frames/second or more was summarized under
technology; and digital holography and super-high speed image super-high speed image measurement . Color video camera
measurement as measurement technologies. broadcasting at 2 million frames/second is already being used at up to
410 x 720 (295,200) image pixels, and it is thought that its role will
7.1 Light source technology for manufacturing steadily grow with more improvements underway in ultra high speed
The usefulness of ﬁber laser as the light source in manufacturing and ultra high sensitivity.
has been gaining prominence. Deep ultraviolet pulse light source is
a Japanese ﬁber laser technology already being used in factories in 8 Photovoltaic Energy (Working Group 7)
inspection equipment. The ultra-short pulse laser has already been 8.1 Crystalline Type Silicon Photovoltaic Cells
used commercially for substrate splitting in the semiconductor ﬁeld There is increasing demand for lower-cost, higher efﬁciency
and as LASIK in the medical ﬁeld, and its usage is expected to spread crystalline type silicon photovoltaic cells, and cells with extremely
to other ﬁelds. high conversion efﬁciency of over 20% are in mass production. In the
Although the hybrid laser has not been solidly deﬁned, all reports cost competition in the whole photovoltaic cell system, including
have positioned it as a laser combining the advantages of solid-state installation costs etc., further optimization is important for competing
laser, semiconductor laser diode, and ﬁber laser. The reports documented against power generating systems that use low-cost cells even if their
different types of hybrid lasers, such as a type in which solid-state laser efﬁciency is not high. From this point of view, there has been active
to amplify seed light from stable ﬁber laser, a type that excites solid- development in HIT solar cells, high efﬁciency solar cells with an
state laser with semiconductor laser diode excitation ﬁber laser, and a emitter-wrap-through structure or a back contact type structure, in
type that serially couples multimode ﬁber and single mode ﬁber in a which either of the p or n layer electrodes are located on the rear
semiconductor laser. surface. Whereas from the cost aspect, improvements in the quality of
In a chirping pulse oscillator, a new scheme is being researched polycrystalline silicon ingots, and the development of new single crystal
where chirping pulse is directly generated inside the oscillator to replace growth technology are being pursued worldwide. There is solid progress
the existing scheme where the ultrashort pulse from the laser oscillator in evaluation of the single crystal grown using the single crystal growth
is stretched outside to obtain the chirping pulse. With this method, technology MONO2 that employs the cast method announced by BP
ampliﬁcation of chirping pulse can be done by attaching it as is to the Solar last year. As for this technology, fresh research and development
ampliﬁer, and it can be applied in simple laser processing also, as large has also begun in other countries such as China. New low-cost raw
pulse output can be obtained from the oscillator unit. materials technology and substrate manufacturing technology are
expected to become even more important in the future.
Annual Technical Report 22
Optoelectronic Technology Trends
8.2 Silicon Thin Film Type Photovoltaic Cells at commercialization for general users. Riding on the tide of energy
The size of thin ﬁlm silicon module surface is worthy of special and environmental issues, color sensitized solar cells are getting noticed
mention. The majority of companies produce modules of 1.4m2 or as prospective next-generation solar cells all over the world, with
more, which is about twice the size of other thin ﬁlm modules. venture companies established and great activity in various projects.
Particularly, the 472W module with a size of 5.7m2 reported by Sun It is expected that implementation of color sensitized solar cells will
Film is striking. If installations of this jumbo size can be standardized get closer to commercialization with the broadening of the base of
in the future, system cost reductions can be achieved by reducing the technology and materials.
wiring materials to a large extent, and even if the performance does
not improve, it can still become an attractive product. 8.5 Organic Thin Film Photovoltaic Cells
As for performance improvement, 10% efﬁciency was reported in We can see that the highest efﬁciency is rapidly advancing, with
Oerlicon s small surface area amorphous silicon. Since there is a above 5% in FY 2008, rising to 6~7% in the current ﬁscal year. As for
possibility that this will lead to improved efﬁciency of tandem solar the overall trend, the development institutes that reported maximum
cells that use this amorphous technology, there are hopes for its future efﬁciency are all university ventures, and the development is being
developments. pursued using funds provided by government, institutional investors,
New trends are seen from the science aspect. This is particularly a businesses, etc.
report on application of plasmonics and photonics in optical conﬁnement Until now, the majority of the cells that have achieved high efﬁciency
effects. However they have still not led to improvements in efﬁciency. have been using n-type fullerene, and bulk heterodiode junction types
There are some questions about their effectiveness in applications such blended with p-type organic semiconductors. The new donor materials
as solar cells that have wide range of wavelengths, and we want to specialized for organic thin ﬁlm photovoltaic cells that have been
watch such developments. developed in earnest from last ﬁscal year, and development of cell
structures using these materials have contributed to the improvement
8.3 Compound Thin Film Photovoltaic Cells of conversion efﬁciency.
This was the year when First Solar s (U.S.) CdTe solar cell module
made a remarkable breakthrough. Meanwhile, major manufacturing 8.6 Super high-efﬁciency solar cells
expansion plans for CIGS solar cells were announced by companies The record for highest efﬁciency has been held for a long time by
in Japan, Europe and the U.S., and they are all set for full scale market NREL (U.S. National Renewable Energy Laboratory) with its inverted
entry. Progress was seen in conversion efﬁciency of CIGS modules, lattice mismatched triple junction cells (40.8%). NREL was followed
with 13.5% conversion efﬁciency being achieved in 60 x 120 cm by Fraunhofer Research Institute (41.1%), and Boeing SPL (41.6%).
opening area, and 10~12% efﬁciency being achieved in commercially The new records showed continued but small improvements. The
available modules. In the U.S., many venture businesses manufacturing inverted lattice mismatched triple junction cell (35.8%, non-
ﬂexible solar cell modules have been established with government concentrating solar) recently announced by Sharp in its press release
support. The new trend seen in the current ﬁscal year is commencement may change the trend. Perhaps the 2010 records on efﬁciency will
of CIGS solar cell turnkey businesses by equipment manufacturers. jump at once, and along with the recent improvement in properties that
Moreover, research and development on CIGS modules has started has helped achieve the remarkable quadruple junction cells, 2010 is
with the backing of the governments of Taiwan and Korea, and it looks likely to see 43~44% development at the lab level.
like this is entering an era of global competition.
As for current status of conversion efﬁciency of CIGS modules, 8.7 Third-generation solar cells
there is a difference of about 6% compared with the small area cells, In recent years, initiatives on third generation solar cells as
and there is large room for improvement. On the other hand, a nanotechnology solar cell applications have been increasing. Initially,
conversion efﬁciency of up to 19% was obtained in small area cells at intermediate band or hot carrier was proposed and researched. Currently,
many research institutions, but since the theoretical efﬁciency is 24%, more than the initially proposed solar cells, there is emphasis on
there still is room for improvement. Furthermore, 25% efﬁciency can arguments for use of conversion efﬁciency in optics management
be achieved with even a single junction, if the ideal pn junction (including plasmon) using nano metals, quantum dots, and Si nanowires.
formation with band gap of 1.4eV becomes successful. These research It seems that ﬁrstly, the possibility of application of solar cells with
results further contribute towards drastic improvements in large area quantum nano wires, quantum dots etc. will be tested as an extension
modules, and also enable differentiation from other modules. to existing semiconductor technologies.
8.4 Dye-Sensitized Type Photovoltaic Cells 8.8 Evaluation Technology
This year there was no improvement in conversion efﬁciency of With the development of photovoltaic power generation, the demand
cells that had been breaking all ofﬁcial records until now. However, for precision improvement of the performance evaluation technique
EPFL s measured results reported the efﬁciency which almost exceeded has gained momentum. Along with that, improved functionality and
12%. In sub modules, ofﬁcially recorded efﬁciency of 8.4% has been precision of technology for accurate evaluation of long-duration
added to Solar Cell Efﬁciency Tables7). credibility that inﬂuences the effective generation volume and
There is progress in various endurance tests, data on durability has generation cost are also being sought. The performance evaluation
been published, and improvement in quality of materials is being technology trends, the credibility evaluation technology trends, and
steadily worked on. Furthermore, there have been demonstrations in the latest trends on standardization were reported. Moreover, the
outdoor ﬁeld tests, and some prototypes have been released for which certiﬁcation trends of each country were also reported.
one can imagine applications utilizing their design characteristics
unique to dye-sensitized solar cells, as part of notable efforts aiming
23 Annual Technical Report
9. Medical technology in the optical industry (Working prevent increased burden on patients, and provide a wider range of
Group 8) options for citizens. It is important to keep track of optical technology
Working group 8 on the Medical Optical-Industry Technology, aiming approved as Advanced medical care, because insurance is expected
at surveying the trends in applications of optical technology to the to be provided for it in the future. Although it is applied in advanced
medical industry and specifying the problems inherent to medical treatments such as percutaneous laser disk decompression (treatment
applications, has done investigation activities since FY 2008. of transpiration of marrow structure present in the intervertebral disks
Optical Coherence Tomography (OCT) is a non-invasive tomographic using laser) used to treat disk hernia, most cases in Japan get treated
imaging diagnostic technology and a hot topic in the bio-optics ﬁeld privately in private hospitals, and some laser medical treatment
in recent years. Near-infrared light topography uses brain blood ﬂow technologies have some fundamentally doubtful points in treatment
information to obtain new knowledge on brain functions. These two itself in which the desired results cannot be obtained if indications are
topics were investigated this ﬁscal year as upcoming opto-medical not selected carefully. In the future, a top priority would be to ﬁrst
technologies. Opto-medical technologies that are approved by Ministry understand the indications and their mechanisms in a scientiﬁc manner,
of Health, Labor and Welfare as Advanced medical care were also and then execute the treatment with laser.
investigated. Continuing from the previous ﬁscal year, marketability
of laser medical treatment in Japan was investigated, and issues faced 9.3 Marketability of Laser medical treatment in Japan
by the medical optoelectrical industry and technology in Japan were In Japan, the production and sales situation of laser equipment for
reported. medical treatment for the ﬁscal year 2009 was unfortunately worse
than the previous year. The reason for the situation going from bad
9.1 New Optomedical technology to worse is the gradual and still continuing decrease in the dental laser
9.1.1 Optical Tomographic Imaging market that had been driving the laser market in Japan for a long time,
OCT is a technology that gives a tomographic image of a living but peaked in ﬁscal year 2002. With the number of years that have
body, to a subepidermal depth of 1~2 mm at a spatial resolution of passed, it was quite possible that a new dental laser would have been
10 m. It is a biometry technology with simple equipment conﬁguration launched, but this does not look likely. This suggests that the medical
that cleverly uses characteristics of optical waves. Based on low laser industry of Japan is facing crisis conditions.
coherence optical interference, OCT selectively detects the direct optic In order to overcome this situation, industry, government and
elements being reﬂected from the interstitial part when light is exposed academia must join hands together and take a common course of action
to the body tissue, and based on this, it constructs a 2 dimensional to develop laser equipment for medical use. Based on new ideas for
tomographic image. This technology was proposed in the beginning the medical system and engineering system and backed by the
of 1990 and was actually implemented only 5 years later in government, internationally competitive business enterprises can
ophthalmology for retinal diagnostics. Now it is an indispensable develop high quality made-in-Japan laser equipment for medical
method of examination in clinical ophthalmology, and is expected to treatment for the ﬁrst time in Japan, thereby contributing to the welfare
see further progress in the future. Moreover, with progress in of the world. Due attention must be paid to the future trends in order
achievement of high resolution and high speed examinations, starting to start such a positive cycle.
with dermatology, its scope of clinical applications is spreading to
digestive system surgery, obstetrics and gynecology, urology, etc. 10. Overseas Field Survey
As part of the Optoelectronic Technology Trend Research Committee
9.1.2 Near-infrared Optical Tomography activities, every year, the committee conducts an overseas ﬁeld survey
The near-infrared topography method was developed in 1995 based on optoelectronic technology development and trends.
on the principles of brain blood ﬂow measurement using a near-infrared This ﬁscal year, investigators were dispatched to WC2009 (Munich)
spectroscopy method proposed by F.F. Jobsis in 1977. It images in September and to WT2010 (Spain) in January to investigate medical
intracerebral hemodynamic variations in brain activity. By developing related trends, and trends in optical materials and devices in a Europe
this from spot measurement to surface measurement, it has been ﬁeld survey. The summary of their reports is given below.
implemented in clinical procedures such as determination of the (1) WC 2009 (Munich) conference
language dominant hemisphere, examination of neurological seizure Investigator: Makoto Sakai (Osaka University)
position, etc. Moreover, in the fundamental neuroscience ﬁeld, previous Fellow investigators: Katsunori Ishii (Osaka University, Observer of
measurement technology had a difﬁcult approach in measuring the Working Group 8)
language functions in newborn babies immediately after birth. With Location: International Congress Center Munich
this technology, there is a newfound knowledge in this area, and it is Schedule: September 6-13, 2009
becoming an important methodology in development science. Further, Summary: Surveyed the trends of research on optical technology in
in near-infrared light topography, many parts can be conﬁgured in the the biomedical engineering ﬁeld. Surveyed announcements
semiconductor, and a noteworthy advantage is that it can be miniaturized in a diverse range of ﬁelds: radiation oncology, diagnostic
in principle. Its expansion to versatile brain function imaging technology imaging, image processing, biosignal processing, modelling
is expected, with progress in research and development. and simulation, biomechanics, telemedicine and e-health,
endoscopy and image guided therapy, diagnostic and
9.2 Laser medical treatment approved as advanced medical treatment therapeutic instrumentation, clinical engineering, active
Advanced medical care is a health care system approved by the implants, biosensors, neuroengineering, rehabilitation and
Ministry of Health, Labor and Welfare. It is recognized as a system prosthetics, biomaterials, cellular and tissue engineering,
that uses ultramodern diagnostic technologies and health insurance artiﬁcial organs, etc. However, it was felt that the research
treatment meant to ensure convenience and safety of the citizens, report on optics technology did not contain much
Annual Technical Report 24
Optoelectronic Technology Trends
information. There should be much applied research on 12. Patent Trend Survey Committee
optical technology in medical and biotechnology ﬁelds. 12.1 Survey of Patent Trends Related to Optoelectronic Technology
It was thought important that this is discussed in a This ﬁscal year, the working group system was continued and
biomedical engineering ﬁeld conference with many investigation and analysis were carried out. Fixed-point observation
participating clinicians and healthcare professionals who was carried out on patent application trends in each of the industrial
actually apply the technology. ﬁelds of optical communication networks, optical memories, display
(2) WT 2010 (Spain) conference, Technical University of Madrid, Visit screens and solar energy. This ﬁscal year, a detailed analysis was carried
to LPI company out on patent trends in each of the technological ﬁelds of ROF,
Investigators: Toshio Katsuyama (University of Fukui) mechanical optical switches, optical ﬁber ampliﬁers, silicon solar cells,
Kimio Tatsuno (Optoelectronic Industry and and concentrating solar cells.
Technology Development Association)
Conference location: Winter Topicals 2010 (Majorca, Spain) 12.2 Informal Meeting with the Japan Patent Ofﬁce (December 9, 2009)
Visit to Technical University of Madrid Meeting participants included: 6 members of the Patent Evaluation
Schedule: January 9-18, 2010 First Section of Optical Devices, including Mr. Nishimura, the
Summary: Winter Topicals 2010 is organized by the IEEE Photonics Evaluation Administrator; and 10 members of the Patent Trend Survey
Society (former LEOS) twice each year in summer and Committee, including Dr. Ito, the Chairperson. This ﬁscal year,
winter. This time it was held for the 3rd time on January Chairperson Ito gave a talk on the theme of Patent Application Trends
11-13, 2010 as Next Generation Photonic Devices and for the Optical Technology Industry, and Requests to the Patent
Applications . The selected topics were important ﬁelds Ofﬁce .
in photonics that have been attracting a lot of attention Mr. Nishimura, the Evaluation Administrator, gave a talk on Recent
recently, with timely theme selection. Overall 60% of the Trends in Patent Administration on behalf of the Patent Ofﬁce.
conference constituted of invited speakers, and there were Particularly, he explained the initiatives on international burden
detailed debates after each session. The conference had reduction and harmony in international applications, policies for
detailed discussions by more than 100 participating improving examination quality, methods for dealing with shift
advanced specialists. amendment, etc. The participants had enthusiastic discussions and
The Technical University of Madrid is involved in exchanged opinions on the contents of the lectures.
organizational work for establishments doing research on
solar energy, and is vigorously pursuing research on 12.3 Patent Forum
Intermediate Band Solar Cells (IBSC). The materials being The OITDA Patent Forum, consisting of reports on the results of
tried are quantum dots, alloys etc. this ﬁscal year s patent trend survey and special lectures, was held in
LPI is a venture that has been developing design Gakushi-Kaikan (Chiyoda-ku, Tokyo) on February 24, 2010. Attendants
technologies such as illumination optics for LED lights, were supporting members and the general public, numbering about 80
aspherical lens for efﬁciently condensing sunlight into people in total.
solar cells, etc. under the technical guidance of Prof. This ﬁscal year, 2 special lectures were given. One was on the topic
Minano and Prof. Benezi of UPD. Optics design Intellectual property dispute and corporations - Practical points to
technology has been Japan s strength and now competitors remember on patents related disputes by Mr. Ryoichi Mimura , a
area appearing. As a policy of Japan, aggressive investment leading person of Japan s intellectual property litigation, who served
in this ﬁeld is expected. as Judge on the Intellectual Property High Court for a long period, and
is a Partner at the law ﬁrm Nagashima Ohno & Tsunematsu. The other
11. Flash Report on International Conferences was on China s science and Technology Strengths and Patents Trends
The Flash Reports on International Conferences constitute an by Mr. Rensei Baba , former Editorial Writer at Yomiuri Shimbun,
information service that distributes the latest trends in optoelectronic specialist on intellectual property strategy and China issues, and a
research and development presented at major international conferences. Professor at Tokyo University of Science.
The reports include the subjective opinions of the author, and are sent
via e-mail within one or two weeks of conferences. This ﬁscal year,
44 ﬂash reports were distributed. The report title, conference dates and
ﬁeld of technology are shown in the following Table.
25 Annual Technical Report