News • 28.05.2018

Self-luminous pixels for a new display generation

How does a display become flexible?

Quantum dots glowing; Copyright: Fraunhofer IAP, Photographer: Till Budde...
Bright colors - a scientist demonstrates how brilliantly quantum dots shine.
Source: Fraunhofer IAP, Photographer: Till Budde

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and their next projects. Display Week is one of the world's leading display technology fairs and conventions, taking place from May 22 to 25 in Los Angeles.

How does a display become flexible?

A prerequisite for a display to be pliant is the flexible base: full flexibility is achieved using a foil. Curved displays use flexible glass material. However, on the path of transformation from flexible substrate to the finished display, there are various steps for the researchers to take. One step is the development of a light source that is also thin and flexible. The integration of self- illuminating pixels that can emit light, for example, by electrical stimulation, makes this possible. Organic light-emitting diodes, OLEDs for short, use such organic light emitters. A proven technology for displays based on organic light emitting diodes is the active matrix OLED technology, short AMOLED. Each pixel has its own power supply. A backlight is therefore not necessary. The display will be even thinner and more flexible.

Quantum dots (QD) are also a suitable material for self-luminous displays. Quantum dot LEDs, QD-LEDs for short, combine the advantages of organic light-emitting diodes with the outstanding luminous properties of the quantum dots. The emission spectra are very narrow band. As a result, the colors look extremely bright. In addition, the low cost manufacturing makes QD-LEDs very attractive for the display market.

So far, existing cadmium-based quantum dots are not future-proof, since the use of cadmium in display production is only possible to a very limited extent from 2020 on, according to the RoHS directive. Nevertheless, market researchers see great potential for the display industry in QD technology. Compared to OLEDs, QD-LEDs not only have a larger color gamut, they are also brighter.

„With every improvement in QD materials, we are moving one step closer to mass-market QD-LED displays”, says Dr. André Geßner, Head of Quantum Dot Development at the Fraunhofer IAP. “What others see as challenges are exciting questions for us that we want to solve with our research on cadmium-free quantum dots.

The Fraunhofer researchers present their promising results on the synthesis of cadmium-free quantum dots at Display Week 2018. The team led by Dr. André Geßner succeeded in producing unique multi-shell quantum dots based on indium phosphide. Integrated in QD-LED components, these cadmium-free quantum dots achieve a significantly higher luminance than cadmium-based systems. Also, indium phosphide-based QD-LEDs almost match the performance of conventional QD-LEDs in other parameters.

Printing pixels on foil or glass

The process of the application of OLEDs or QD-LEDs to the flexible substrate determines the flexibility of the finished display. Large layer thickness limits flexibility. Inkjet-printing has proven itself, but there are even better methods. For RGB AMOLED displays, Fraunhofer IAP and its partners are researching a new printing process for which they plan to achieve a minimum of 300 ppi in the intended demonstrator.

With the electrostatic printing (ESJET), the scientists led by Dr. Christine Boeffel are investigating a printing process with which much finer and more uniform structures can be printed than with inkjet printing. ESJET printing is a new technology of processing ink by applying an electrical voltage. This allows for a much wider range of printable inks and even pastes. The drop-on-demand system so far achieves droplet sizes of less than 20 microns.

„The size of 20 microns is already sufficient to print a display with 200 ppi. According to our knowledge, this is the highest resolution achieved by inkjet printing, yet. Our goal is to print a 300ppi RGB AMOLED display utilizing ESJET printing. We want to accomplish this with pixel sizes of 10 microns", explains Dr. Christine Boeffel. In her presentation, she will show the interim result of the ongoing research project Hi-Response.

Source: Fraunhofer IAP

related articles:

popular articles:

Thumbnail-Photo: Smart meters: Be proactive and reap the benefits...
12.08.2019   #energy optimization #electrical installation

Smart meters: Be proactive and reap the benefits

The Metering Point Operation Act calls for smart meter rollout

The black and analog electric meter box has become obsolete: The mandatory smart meter rollout will commence in a few months. What does the installation of digital, smart electric meters mean for retailers and chain stores? ...

Thumbnail-Photo: Retail service robots – helper or footfall generator?...
22.07.2019   #pos marketing #services

Retail service robots – helper or footfall generator?

Using drag and drop to train the new coworker

Many of us know their faces, even if we have never met them in person. One of these faces belongs to Pepper, the humanoid robot. It has fast become a media star. ...

Thumbnail-Photo: The future of retail: AI is changing everything...
08.07.2019   #digital marketing #visual merchandising

The future of retail: AI is changing everything

AI-enabled systems help retailers understand their customers

For retailers, winning is still all about delighting the customer. The trick is to move fast enough and to be as nimble as possible to satisfy the customer not only today, but in the future. ...

Thumbnail-Photo: Pay cash? Via code!
26.08.2019   #mobile payment #app

Pay cash? Via code!

Shop online, pay the bill offline

Barzahlen.de relies on good old cash. The concept of the Berlin start-up: shop online, pay in cash at the store. Swimming against the trend of fast online shopping and mobile payment is paying off, says Weina Wang, Head of Retail. In an interview, ...

Thumbnail-Photo: Retail analytics: Breaking down data silos and improving operational...
29.07.2019   #data management #data analysis

Retail analytics: Breaking down data silos and improving operational efficiency

How comprehensive data usage led to higher revenue at Heine

“As a business with heritage in mail order, we used to have access to detailed reports about product performance in our catalogues. Once our digital presence grew, we had very limited information available that combined the KPIs for both our ...

Thumbnail-Photo: Denmarks largest garden center chain is chasing a green profile...
26.06.2019   #sustainability #electronic shelf labels (ESL)

Denmark's largest garden center chain is chasing a green profile

Electronic shelf labels for paper reduction

Plantorama introduces electronic shelf labels in all stores, which significantly reduces the chain's paper consumption. The project will strengthen the chain's green profile and will have a positive influence on the customer experience and ...

Thumbnail-Photo: retail trends 3-2019: focus checkout zone
16.09.2019   #mobile payment #customer satisfaction

retail trends 3-2019: focus "checkout zone"

Shopfitting, technology, marketing: What does a checkout have to do nowadays?

Read our latest edition retail trends 3-2019 online as an e-paper. ...

Thumbnail-Photo: drs//POS – The POS system for many check-out situations...
13.09.2019   #pos systems #cashpoints

drs//POS – The POS system for many check-out situations

With the POS system developed by Superdata you are put in the picture

The POS acts as an ear in the store. It affects how timely, and with what information, decision makers at the head office are in a position to assess developments in the store and are able to respond appropriately to the situation.With our POS ...

Thumbnail-Photo: Retail Asia Conference & Expo (RACE)
07.10.2019   #online trading #retail

Retail Asia Conference & Expo (RACE)

As the leading retail exhibition in Asia, RACE is taken place from 6 – 8 May 2020.

As the leading retail exhibition in Asia, RACE is recognised as the must-join event among the industry’s most influential retailers and customers. RACE features three focus areas: Retail technology, retail design & in-store marketing ...

Thumbnail-Photo: Tackling organized retail crime with video analytics...
26.06.2019   #video surveillance #digital video surveillance

Tackling organized retail crime with video analytics

Inpixon joins forces with National Anti-Organized Retail Crime Association

Inpixon, an indoor positioning and data analytics company, announced it is collaborating with the National Anti-Organized Retail Crime Association (NAORCA Worldwide) to combat retail crime by providing a free 90-day trial offer for IPA Video™ ...

Supplier

Superdata GmbH
Superdata GmbH
Ruhrstr. 90
22761 Hamburg
Delfi Technologies GmbH
Delfi Technologies GmbH
Landgraben 75
24232 Schönkirchen
Permaplay Media Solutions GmbH
Permaplay Media Solutions GmbH
Aschmattstr. 8
76532 Baden-Baden
iXtenso - Magazin für den Einzelhandel
iXtenso - Magazin für den Einzelhandel
Celsiusstraße 43
53125 Bonn
APG Cash Drawer
APG Cash Drawer
4 The Drove
BN9 0LA Newhaven