cens logo

Materials Science Prof in Taiwan Simulates Sunlight With OLED Technology

Easy-on-the-eye lighting

Jan 13, 2010 | By Ken Liu

Though not often talked about in the industry but the fact is that most of the currently available lighting sources as LCDs, plasma panels, LEDs, traditional and compact fluorescents etc. all emit light, instead of reflecting light off surfaces to be absorbed by the human eye, which is nature's plan. The makers and sellers of these light sources won't, for obvious reasons, talk about one of their major downfalls: causing eye fatigue, in extreme cases dry eye, after prolonged exposure. But the Holy Grail in artificial lighting may have been found in Taiwan, specifically by a material science and engineering professor at the National Tsing-Hua University in Taiwan. J.H. Jou and his graduate-school students have discovered a way to faithfully simulate sunlight, and perhaps offer much needed relief for countless workers in the e-age.

 One of Jou`s chromaticity-variable OLED. The four pictures showing  different color temperatures. (photo courtesy of Jou). One of Jou`s chromaticity-variable OLED. The four pictures showing different color temperatures. (photo courtesy of Jou).

The recently announced, unique technology enables a white-light organic light emitting diode (OLED) panel to emit light with the same dusk-to-dawn wavelengths as natural light.

Simulating Sunlight
"By varying the voltage through the OLED panel from three to nine volts can produce ambient light simulating natural light that changes from dawn to dusk. Truly there is genius in simplicity as this plain driver-IC can automatically modulate the voltage to render any desired color temperature between 2200 and 8000 K anytime," says Jou, who is also credited with reportedly introducing the world's first OLED rated at 51 lumen-per-watt in 2002.

As the discovery of Velcro, a fluke led Hong Kong-born Chinese scientist Dr. Ching W Tang and Steven Van Slyke at Eastman Kodak to eventually invent in 1987 the first OLED: one day in 1977 the scientist doubled back to the lab to pick up something forgotten only to see an experimental organic battery glowing in the dark, and the rest is history.

An OLED is typically of a micro-multilayered structure sandwiched by an aluminum cathode layer and another anode layer of transparent indium tin oxide (ITO), with layers of organic semiconductors in between.

Just like chip-based LEDs, OLEDs emit light by electroluminescence. A voltage applied across the electrodes motivate electrons into the semiconductor layer near the cathode and then released at the anode-leaving behind positively-charged electron holes. Traveling through the semiconductor layers, the electrons fill these holes, with such process emitting photons.

The major difference between OLED and LED is the illumination format: the former being a panel-light source whereas the latter a dot-light source. Also, developers of the two have gone in different directions, with OLEDs, which are markedly thinner than LCD modules, competing against liquid crystal display (LCD) while LED mainly being developed as lighting.

Open Mind Helps
As a display medium, Jou notes, OLED is seen as a flop when the voltage applied keeps varying. But keeping an open mind may have helped the scientist for an impractical display medium, one hobbled by varying voltage, has turned out to work well as a groundbreaking light source. Around a year after developing a voltage-controllable OLED, Jou's team unveiled a workable technology in July this year, which the professor says is the world's first OLED light simulating sunlight.

According to Jou, a University of Michigan PhD in macro-molecular science and engineering, Lumiotec, a lighting subsidiary of Mitsubishi Heavy Industries, is the world's exclusive supplier of OLED lights, but its products are mono-chromatic-giving off light as if on a cloudy day.

Multi-nation Patent Pending
Besides having applied for patents on the OLED technology in five nations, including the United States, South Korea and Japan, Jou has also had relevant papers published in the Applied Physics Letters (APL), an American Institute of Physics' journal that features reports on significant findings in applied physics.

The discovery of the OLED lighting technology has Jou bubbling with confidence, so much so that the professor touts the technology will dominate indoor lighting. "OLED's non-flickering, sunlight-simulating, non-irritating characteristics wield pivotal advantages over fluorescent lamps and LEDs as indoor lighting. Although incandescent bulbs are also easy on the eye, they are energy-inefficient and produce excessive heat," he notes.

The variable chromaticity, sunlight-simulating characteristics of OLED, Jou stresses, make such light source especially desirable in high-latitude countries, where winter nights are much longer than daylight hours. "So OLEDs allow residents in northern latitude nations to enjoy natural daylight even during gloomy winters," he notes.

Energy-efficient Too
More merits are going for OLEDs: According to Philips, also developing OLED lighting technology, OLEDs could be 10 times more energy-efficient than standard incandescent bulbs and around three times more efficient than energy-saving compact fluorescent lamps (CFLs).

Aiming to reduce CO2 emissions by 20% by 2020, the EU has partially funded two research projects focusing on OLED technology through its Research Framework Program. In June 2008, the project announced its success in developing a white-light OLED with 50.7 lumens-per-watt, a start-up brightness of 1000-candelas per-square-meter, and a lifetime above 10,000 hours. In September 2008, the OLED100.eu project began aiming to develop OLEDs with 100 lumen-per-watt, the current benchmark.

According Jou, a May 2009 German academic journal reported an OLED with 90 lumen-per-watt at 1000 candela-per-square-meter. "Japanese manufacturers plan to mass-produce 50-lumen-per-watt OLEDs at 5,000 yen per 15-square-centimeter in 2011," he says. "OLEDs have come a long way...initially they only shone at less than one lumen-per-watt," Jou notes.

Big Player Support
Such lighting technology is apparently not a fad. Jou says that OLED's user-friendly characteristics are as attractive to major players as light to moths: bringing onboard the world's top- three lighting makers Osram, Philips and GE as well as Taiwan's display-panel players as AU Optronics and Chi Mei EL Corp. The professor estimates OLED lighting to generate up to NT$200 billion (US$6 billion at US$1:NT$33) in 2018 global revenues, and command one quarter of the world's lighting market in 15 to 20 years, as well as reduce nearly seven million metric tons of green-house gases.

In spite of considerable support of big players, the OLED path is not unconditionally lit with promising light for technological hurdles awaiting to be cleared. Jou notes that, despite OLEDs being better wide-area illuminators than LEDs, rising panel size tends to compromise luminous efficacy, with the function of doubled brightness and lifetime becoming a critical issue.

Challenges notwithstanding, Jou remains upbeat about the future of OLED lighting. "White-light OLEDs, at its unveiling in 2000, emitted only one lumen- per-watt. Such brightness has risen to 50-60 lumen-watt along with panel sizes. So we can reasonably expect to see the OLED100.eu project to deliver 100-square-centimeter panels emitting 100 lumen-per-watt that are priced below 100 euro," he notes.

Philips Research is already contemplating even brighter dreams. A Philips Lighting scientist says that 150 lumen-watt OLEDs should be achievable once the 100 lumen-watt threshold will have been crossed.

Industry Reports

Functionality and PPE in Spotlight at Upcoming TITAS Expo on 10/13</h2>

Functionality and PPE in Spotlight at Upcoming TITAS Expo on 10/13

Sep 30, 2020

The upcoming Taipei Innovative Textile Application Show (TITAS) is entering its 24th edition, with 803 booths, 356 exhibitors from 11 countries, including Taiwan, Sweden, Germany, Japan, South Korea, Switzerland, the U.S., Vietnam, Hong Kong, Singapore, and China. Innovation, environmental-awareness, and products gearing towards the post-pandemic market are the focal points at TITAS. The five ...

Samsung's Potential Mini/Micro LED Partnership with Taiwanese Firms</h2>

Samsung's Potential Mini/Micro LED Partnership with Taiwanese Firms

Sep 28, 2020

The world's leading memory chip and smartphone maker Samsung Electronics is looking for potential display technology partnerships in Taiwan, specifically for mini/micro-LED industry applications. Local media Economic Daily News reported Samsung was partaking in a private project with LED driver IC supplier Macroblock Inc., a move signaling the Korean group's further ambition in the mini/micro-...

Strong Global Trade Rebound for Two-Consecutive Months: CPB</h2>

Strong Global Trade Rebound for Two-Consecutive Months: CPB

Sep 28, 2020

Since July, global trade volume continues to rebound, signaling economies' restarting in a bid to make up the worldwide lockdown this spring due to the pandemic. In a report released by the CPB Netherlands Bureau for Economic Policy Analysis, the CPB World Trade Monitor in July grew 4.8% compared to June, the largest increase since the bureau began compiling statistics in 2000. This is slightl...

Industry In-Focus

ITRI Forms Industry-Gov Alliance for Universal EV Charging Platforms</h2>

ITRI Forms Industry-Gov Alliance for Universal EV Charging Platforms

Sep 29, 2020

Industrial Technology Research Institute (ITRI) has allied with around 50 firms and government agencies to develop electric vehicle (EV) batteries technologies, seeking to roll out a standardized platform and allow EVs of different brands to use the same batteries. The alliance aims to cultivate the island's EV industry and offer customers a more diverse selection of charging options to choose...

Latest PCB Industry Report NTI-100 Shows Growing Asian Reach</h2>

Latest PCB Industry Report NTI-100 Shows Growing Asian Reach

Sep 23, 2020

Global PCB NTI-100 2019 Fabricators report from the research agency heavyweight N.T.Information showed companies with over USD$1 billion revenue have increased compared to 2018. The report, annually compiled by Dr. Hayao Nakahar, showed in 2019, 122 fabricators were listed reporting revenue over USD$1 billion, an increase of four companies compared to the 2018 list. The report also found more ...

Surgical Masks: the New Battleground for Textile Industry</h2>

Surgical Masks: the New Battleground for Textile Industry

Sep 22, 2020

With most of society worldwide becoming more and more accustomed to wearing masks in the post-pandemic era, it has become a must-have accessory, attracting domestic textile firms into production. Traditional textile firms, such as Eclat Textile, Makalot, Far Eastern New Century, Everest, Roo Hsing, and QVE, have begun making masks, reports say. The COVID-19 pandemic has led to fewer consumers ...

Supplier News

Sheh Fung owns three factories, one of which located in Mituo District, KaoHsiung primarily focuses on packaging and heading.

Sheh Fung Screws' Profitable Q3 Prompts Goal for NT$2 Billion Sales by Year-End

Sep 24, 2020

■ Huang Chih-ming Located in Kaohsiung, Taiwan, Sheh Fung Screws Co., Ltd focuses on manufacturing three categories of screws: self-drilling screws, painted screws, and wood screws, often found in wood construction, sheet metal roofs, wood footpath, and DIY home decor applications. Currently, the U.S. is the firm's primary market, making up 64% of sales, 7% for Europe, 6% for Asia, and 12% for...


Chipboard Screw, Special Wood Screw, provided by Shuenn Chang Fa

Quality Fastener Maker Shuenn Chang Fa Shows Resilience with Sales Boost

Sep 24, 2020

■ Huang Chih-ming Taiwanese quality fastener manufacturer Shuenn Chang Fa Enterprise Co., Ltd.'s (SCF) presented exceptional ability to adapt to challenging times amid the COVID-19 pandemic. Unlike other firms, SCF leveraged its production strategy with its new plant, and even saw sales performing better than expected. SCF’s newest factory expands the original 10,000-square meters factory g...


Stainless Steel Screws, provides by Ray Fu Enterprise Co., Ltd.

Ray Fu's Reliable Fastener Quality for Clients Bolsters Q4 Sales

Sep 24, 2020

■ Huang Chih-ming Ray Fu Enterprise Co., Ltd. is a Taiwanese professional exporter for various fasteners and steel wires. Along with its parent company Chen Nan Iron Wire, both firms are located in Kaohsiung City of southern Taiwan. Ray Fu manages a wire rod storage, spheroidizing annealing furnace, pickling surface equipment, wiring drawing machinery, and fastener forming machine. While the C...


Insiders' Views

Caption: Pictured from front row, third right, Changhua County Government Economic Affairs Department Director Liu Yu-ping, County Magistrate Wang Huei-mei, Secretary Chen Bo-tsun pose in front of the exhibition booth. (Photo provided by CHCIA)

Changhua County Government Shores up Biz-Matching to Global Buyers

Nov 18, 2019

■Yang Feng-Chun In a bid to assist manufacturers in Changhua County to expand their market reach overseas against severe competition in the globalized market, Changhua County Government has been an active player in pushing for a makeover and innovation of its local small and medium-sized enterprises. This is done in hopes of establishing stronger connection with international markets. An ex...

Paul Master offers high-quality chassis and engines parts for passenger cars, trucks, and industrial trucks. (Photo courtesy of Paul Master)

Paul Master Builds Reputation with Auto Chassis and Engine Parts

Nov 18, 2019

Founded in 1980, Paul Master Auto Parts Co. is headquartered in Taiwan, a professional manufacturer of chassis and engines parts for passenger cars, trucks, and industrial trucks including forklifts. General Manager Terry Liang said the company has its own professional design department, which provides customized products and specifications for global buyers, including automobile steering and...


Nan Hoang Traffic Instrument Co., Ltd.</h2><p class='subtitle'>Taiwan First brakes Technology Co., Ltd. </p>

Nan Hoang Traffic Instrument Co., Ltd.

Taiwan First brakes Technology Co., Ltd.

Sep 04, 2019

Nan Hoang Traffic Instrument Co., Ltd is one of the major manufacturers of automobile friction materials in Taiwan and globally. Chairman Austin Cheng has implemented the double-arrow strategy this year - own brand of “YangPo” is adopted to focus on global channels while the “NHC brand focuses on improving market shares in global markets, such as Europe, America, Asia, Australia, and the Middle E...

Exhibition Highlights

Stable Development and Popular Fastener Show in China</h2>

Stable Development and Popular Fastener Show in China

Sep 11, 2020

Driven by market prospects, domestic and international exhibitors actively prepare International Fastener Show China in Shanghai on November 3-5, 2020. Suffering from global epidemic and quarantine nearly half year, exhibitions are hot and popular in mainland China. Thousands of visitors join and visit the exhibitions with inquiries, and are eager to know new technology. Domestic and inter...

2020 Medical Taiwan to Host In-Person and Virtual Events</h2>

2020 Medical Taiwan to Host In-Person and Virtual Events

Sep 10, 2020

2020 Medical Taiwan is slated to kick off on Oct. 15 to Oct 17 at Nangang Exhibition Hall 2. Aside from events at the show, show organizer Taiwan External Trade Development Council (TAITRA) is also hosting the “Medical Taiwan Virtual” online edition at the same time due to travel restrictions impacted by the COVID-19 pandemic. The virtual edition will present 200 exhibitors and over 700 medic...

Automechanika Shanghai 2020 reveals online tools to navigate current trends and post-pandemic opportunities</h2>

Automechanika Shanghai 2020 reveals online tools to navigate current trends and post-pandemic opportunities

Sep 01, 2020

Ms Fiona Chiew, Deputy General Manager, Messe Frankfurt (HK) Ltd, reflected that: “As the industry starts to spring back from the effects of COVID-19, we believe that highly influential platforms like Automechanika Shanghai play a crucial role rejuvenating the market. It is our mission to help players unlock their potential. Therefore, we are continuing to realign our resources by utilising new d...