ET/IT & TI Elektronische Displays : E- & Flexible Displays

&

Karlheinz Blankenbach

Pforzheim University, Germany

Prof. Dr. Karlheinz Blankenbach Phone : +49 7231 - 28 - 6658 Pforzheim University Fax : +49 7231 - 28 - 6060 Tiefenbronner Str. 65 Email : [email protected]

D-75175 Pforzheim, Germany Web : www.displaylabor.de

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 1 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays Overview

Introduction

E-Paper Displays & Applications

Flexible Displays & Challenges

Summary

Some pictures etc. are courtesy of the companies named on the picture, others from, e.g., SID, … Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 2 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Paper Like Displays (PLD) as System

Paper + Display (System) = E-Paper (System)

- Bi-stable - Rewritable - Thin & light - Re-use - Flexible - Portable Merits - Design free - Storage - Readability + - Data access - Low cost - Moving images - Ease of use

Shortcomings - Re-use - Bi-stable Short- of e-paper - Data access - High cost comings displays ? - Static content - Rigid & heavy

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 3 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Electronic Paper • Idea : Replacement of paper (, price tags, billboards, ...) • Advantage : 'Re-write' within seconds

• Bi-stable and reflective  Lowest power consumption

• Small pixel size  High resolution (... 200 dpi)

• Flexible possible  Requires plastics and organic electronics

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 4 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Definition of “Advanced Paper” Softcopy Type Hardcopy Type PLD RWP (Paper Like Display) (Re-Writable Paper) • Near display, but display • Near paper • Holds data without power • No power supply needed • Rewritable without printer • Rewritable by printer

RECO-ViewTM Monochrome RWP Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 5 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

E-Paper Display Market Revenue Forecast

Million USD per year

Source: DISPLAYBANK

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 6 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

E-Paper Application Trends CE

CE MP fuels Monochrome professional

Professional

Color CE

Low power (color) displays for professional applications can enter mass production. Source: KB, E-, QUALCOMM

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 7 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Main Optical Issue for E-Paper Displays : Readability

• High Whiteness (close to paper, eye adaptation)

• High reflectivity (reflectance > 40%; newspaper, magazines >80%)

• Black & white Contrast Ratio > 10:1 for readability

• Good color reproduction – the challenge for E-Paper displays

• High resolution (> 150 ppi for personal devices)

• Response time moderate if no video required

All R&D (beside materials and processes) focus on optical performance

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 8 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Display Technology vs. Ambient Light : Sunlight Outdoor

Transmissive color AM LCD Reflectivity of paper > 80% Display is ON! Reflective E-INK EP

E-Paper is closest to paper

Reflective b/w Transflective Reflective PM LCD Color AM LCD MUX LCD

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 9 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Trimode TN LCD by PIXEL QI

• Trimode = transmissive + transflective + reflective in one display

• Benefit: compromises power consumption and sunlight readability

• Best color in transmissive mode

• Monochrome (incl. grey levels) for reflective mode

Transmissive

Reflective

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 10 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Trimode TN LCD by PIXEL QI vs. E-INK

E-INK : monochrome & no video, “no” power PIXEL QI : monochrome (low power) or color (high power), video

Indoor Outdoor

PIXEL QI

PIXEL QI E-INK E-INK

E-INK without frontlight but readable E-INK higher white reflectivity

PIXEL QI excellent & color (video) PIXEL QI monochrome & low power but high power (transmissive) (reflective)

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 11 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Trimode TN LCD by PIXEL QI

Contrast Ratio (measurements performed @ Display Lab) 100

Transmissive (color)

10

Reflective (monochrome)

1 10 100 1,000 10,000 100,000 Illuminance (diffuse) /lx

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 12 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Why Is Color Performance of E-Paper So Poor ?

100% white 33% 10%

33% Ideal reflector: 100% Eo-layer: 30% Each color filter absorbs 33% (simple model) Poor reflectivity & non-saturated color for side-by-side color (CMY stack better) Color KINDLE: IPS LCD !!! What is not drawn: color filter and eo-layer is passed twice. This is taken into account via %-values. Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 13 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Reflectivity & Color Performance of E-Paper Technologies

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 14 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Reflectivity & Color Performance of E-Paper Technologies

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 15 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Power Consumption vs Display Technology

Power consumption (typical values)

Standard AMLCD iPad 10h LCD savings depend strongly from AMLCD + FSC + 2DD content and ambient light

AMOLED 80% black Black background not good for e-books

AMOLED 80% white

E-Paper day • Lack of multimedia KINDLE 300h

E-Paper night • Most e-paper technologies are not transparent

Low power consumption is crucial for many applications !

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 16 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays Overview

Introduction

E-Paper Displays & Applications

Flexible Displays & Challenges

Summary

Some pictures etc. are courtesy of the companies named on the picture, others from, e.g., SID, … Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 17 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

E-Paper Display Fundamentals

Cross section of a typical e-paper display

Substrate incl. barrier layer Front plane Color filter (option)

Here focus on eo-layer eo - layer as panels are similar

Matrix drive, x-Si, electronics Back plane Substrate incl. barrier layer, reflector as option (not to scale)

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 18 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays Reflective Electro - Optic Layer Technology Overview

Electrophoretic Reflective LCDs Other

- Wet (E-INK) - Bistable TN - Electro Chemical

- Dry - Reflective TN* - Electro-Chromic* - In-plane ep - Smectic - Electro Deposition

- Electro-kinetic - Guest Host - Electrowetting / -fluidic - PDLCD* - MEMS „Not all technologies - ChLCD are listed or presented“ - P-INK

• Many technologies, but only a few in MP, some in lab status • Reflective TN (e.g. watches) run for years on a small battery

*: low power but not fully bistable

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 19 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Nomenclature for Electronic - Paper Technologies

Electrophoresis is the movement of an electrically charged substance under the influence of an electric field. This movement is due to the Lorentz force.

Electrochromism is the phenomenon displayed by some chemical species of reversibly changing color when a burst of charge is applied.

The electrowetting effect was originally defined as "the change in solid electrolyte contact angle due to an applied potential difference between

the solid and the electrolyte". from WIKIPEDIA

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 20 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays Typical Reflectance Values of Reflective Displays

White State Reflectance x % Display Technology of Monochrome Display * „White paper“ 80 % Mono- chrome „News paper“ 55 % Reflective TN 90° 25 % „Standard technology“ White Taylor guest host 50 % PDLC with polarizer 30 % *: Typical values Ch LCD 40 % from 40 % various Electrowetting 60 % sources MEMS 45 % Electrochromic 30 % Reflectance: In-plane electrophoretic 70 % Higher means better

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 21 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

E-Paper Display Technologies Forecast

Source: DisplaySearch 2009

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 23 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Electrophoretic Wet - Type: E Ink • Principle: Microcapsules with black and white, opposite charged particles • Color by RGB(W) filter, new: “red” as third microcapsules

Light State Dark State +

+ + + + + + ++ + + Electrode Electrode

• Most advanced technology, in mass production • Leader in e- readers • Customized displays like 8-Segments are pushed • E Ink‟s e-o layer is used by many panel makers

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 24 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays Selected Examples : E INK SURF Reflectance ~ 40+%

10 mm

Power consumption: Not backlight-able 0.5 µA while switching @ 5 – 15 V (only display)

R&D temperature range: -20°C … +70 °C Private communication: If „more“ approach E-INK

Source: E Ink Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 25 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

E - Paper by E-INK

Positive & negative E-INK (left) vs. E-INK mode via software LCD (right) SPECTRA

3 advantages: - GUI change by software - Higher reflectance than reflective LCD Source: E-INK - Vivid red Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 26 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

E - INK Technology

RGB + White (RGBW) square subpixel:

The white subpixel enhances the brightness and dynamic range with minimal impact on color saturation.

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 27 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Examples of E INK Displays in Mass Production  2013

Sources = names … most take only use of plastic substrate (unbreakable) ! Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 28 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Reflective LCDs • Principle: TN LC transmission is modulated by voltage • Area color feasible, full color hardly to achieve due to low CF transmission

Re- L flec- C tor D

Features: • In mass production since decades • Low reflectance: ~ 20 % (monochrome) • Flexible easy to achieve due to MUX or PM • Segment 8 to QVGA graphics displays • Low voltage (~ 3 V) • Low viewing angle performance Source: KB Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 34 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Reflective LCD Display Prototype Technology also very interesting for smart gear !

PDisplay Module  50 mW

Black surrounding tricks vision on white reflectance Source: KB, JDI Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 35 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

SHARP MEMORY LCDs • Polymer Network Liquid Crystal • Polarizer free  high reflectance

Table by SHARP

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 37 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Trimode TN LCD by PIXEL QI

• Trimode = transmissive + transflective + reflective in one display

• Benefit: compromises power consumption and sunlight readability

• Best color in transmissive mode

• Monochrome (incl. grey levels) for reflective mode

Transmissive

Reflective

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 38 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Trimode TN LCD by PIXEL QI vs. E-INK

E-INK : monochrome & no video, “no” power PIXEL QI : monochrome (low power) or color (high power), video

Indoor Outdoor

PIXEL QI

PIXEL QI E-INK E-INK

E-INK without frontlight but readable E-INK higher white reflectivity

PIXEL QI excellent & color (video) PIXEL QI monochrome & low power but high power (transmissive) (reflective)

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 39 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Cholesteric LCDs (ChLCD) • Principle: Special liquid crystal, no polarizer, Passive Matrix, CMY stack • Color by dedicated LC reflection

FUJITSU BMGMIS, MAGINK

KENT

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 40 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Other Reflective & Bistable LCD Technologies

Bistable Nematic Zenithal Bistable Smectic A

BiNem by NEMOPTIC ZBD PolyDisplay, Kent, …

MP started in 2009 but Millions of electronic quitted some years later. shelf labels sold. No MP. Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 41 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Electrochromic Displays • Principle: Color changes by charging • Color by liquids incl. stacking (RICOH)

Features: • Reversible color change depending on charging state • Direct, PM and AM • Low voltage (~ 1.2 V) • Slow update (seconds) RICOH

AVESO Sources = names Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 44 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Membrane PLDs : Interferometric Modulator (IMOD)

• Principle: Electro-mechanical modulation of optical cavity • Color by by optical interference of reflected light

QUALCOMM (MIRASOL)

• High reflectivity as no color filters or polarizers are needed

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 45 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Electrowetting Displays : Selected Prototypes, No MP

• LIQUAVISTA Video-speed (  LIQUAVISTA  SAMSUNG  ) 8.5” XGA AM 6.2” SVGA AM

• ADT

Bistable Indicator 7“

• GAMMA DYNAMICS

(Sources: Companies, KB) Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 46 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Electrowetting PLDs : LIQUAVISTA „Analogue‟ EW by area Not bi-stable

Water

• Demonstrators up to VGA SID 2009

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 47 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Electrowetting Display : Droplet Moving (ADT) • Principle: Droplet moving • Color by fluids, CMY stack

R V

Data Electrode

Oil H Water D E1 E2 E1 E2 E1 E2 Control Electrodes

• True „No Power‟ display • Passive Matrix driven (low cost) • Pixel size 0.5 … 10mm • High reflectivity, backlight-able

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 48 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays Electrokinetic by HP: R&D

Movement of the particles

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 51 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Comparison of Major Bistable E-Paper Technologies (typical data) E-INK SIPIX QR-LPD EC EW xLCD MEMS

B/W reflectivity* + + + ++ ++ + +

Backlight-able - - - - ++ - … o -

Contrast ratio + + + + ++ o +

Color o + o - + + +

Response time o o ++ - - o +

Pixel scale-ability + - - + + + -

Drive AM AM PM AM PM PM AM

Too many technologies (~ 12) with different merits and issues

*: Data by Heikenfeld, NATURE PHOTONICS, VOL 3, MAY 2009 / other sources: Pala, DENSO, V&V Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 52 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Summary “E-Paper” 100 CR Transmissive Electrophoretic • Most of reflective displays are mono- 10 Reflective LCDs chrome and low res. Reflective 1 EC, EW, P-INK, … • Optical performance Illuminance of some reflective techniques better than reflective LCDs • Reflective displays • Many reflective and bottom line: bistable display - Sunlight readable technologies exist. E INK - Low power • Some are already - Flexible in MP, others in - E INK competitive prototype phase. to reflective LCDs LCD

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 53 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

E-Paper Applications Overview for Replacing Paper

Information Terminal High Function ÅiÅf06 EuroHighpe ÅjÅkiRex Ål content & function High Cost Watch ÅiÕ05 Seiko Åj e-ReaderÅiPLD for Documents Åj ÅkEPSON Ål SmartÅ® Å@PDA phone e-Book E-book Traffic AD ÅiÅf06Tokyo Station Åj É•Book Watch ŅLibrie Ó ÅkHitachi Ål Watch ÅiÅf04& Åf06 ) ÅiÅf04 Panasonic) ÅkE Ink Ål ÅkKent Ål Large Size Small Size e-Paper ÅiUndecided Åj Laptop? Bill- Card Size ÇVinches ÅkEPSON Ål A4 A3 boards Small Advertisement Large size Price Tag e-Paper Smart ÅiPLD for size Documents Åj cards Å®Document Viewer e-Paper ÅiÕ06) Low Cost Price Tag ÅiÅf06 Mitsukoshi Åj ÅkFuji Xerox Ål ÅkFujitsPriceu ÅlÅiPOS system l inked with RFID Åj tags Low Function Signs Status control Low cost Low content & function High cost

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 54 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Indicators : ADTs „No Power‟ Electrowetting

Saving green house gases by replacing LEDs by no power indicators !

Today: Tomorrow: ADT LED replacement LED indicators draw ~ 50mW each, resulting in MW in Europe. EU: Stand-by  0.5 W 2s of power,  1 LED  10% lasts for „years‟

Other applications Household „true white‟ display Wireless switch Design: White display even with no power

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 55 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Meters … Watches basing on E-INK‟s EO-Layer

Lowest power & reflectivity enables new designs and functionality

Feasible but yet limited acceptance Red brick wall Sources = names Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 56 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Smart Cards Amount of money if the display Main requirements: fails e.g. 8888.88 ?

• Durability

• Bendable

• No power (change only when in reader or limited SIEMENS EC power to change SIPIX EP (quitted) for RFID) MICROCUPS

Smart cards like money card or with various applications would be pushed if having a display !

Sources = names

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 57 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Electronic shelf labels

Main requirements:

• No or lowest power

• Good readability

• Low cost

• Control system enabling integration into business process

• Replace paper tags • Business case for wireless price updates Sources = names

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 58 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

PDAs & Smart Phones

Main requirements:

• Foldable or rollable

• Good readability also for color

POLYMER VISION READIUS with E-INK

Slim line mobile device with large screen but potentially low acceptance without color

Sources = names Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 59 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

E-Book Readers Overview (not all listed) “monochrome”

- Jinke Electronics: Hanlin versions V8, V2, V3, - Sony Portable Reader PRS‐500, Libre EBR_1000, PRS‐505 - IRex Technologies: iLiad ER‐0100 - Hon Hai Precision Industries: - ERead: STAReBOOK STK101, - Frontech‐: FLEPia A4, FLEPia A5 - Booken: - Polymer Vision: Readius - IRiver: Iriver e‐Book - NeoLux of South Korea: NUTT - Ricavision: Home E‐Reader - Apple: iBook - … Color prototype(s) • Larger size for newspapers (easies „distribution‟) FUJITSU • E-books compete with netbooks and smart phones ChLCD • Advantage is sunlight readability and battery life • Is this „enough‟ to buy an additional device? (because of limited multimedia performance)

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 60 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Signs POLYDISPLAY Smectic A

Main requirements:

• Large(r) size

• Sunlight readability

• System integration incl. wireless data trans- mission and solar powered SAMSUNG E-INK AEGMIS ChLCD

Many advantages but potentially limited acceptance without color VOSSLOH for some applications E-INK Sources = names

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 61 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Billboards

Main requirements:

• Large size (10 m²) ChLCD RGB • Sunlight readability stacks, tiled:

• Mullion-free AEGMIS

• Excellent color reproduction MAGINK

• Wide viewing angle

Large market with only LED-walls as competitor

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 62 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Applications for Major Bistable E-Paper Technologies

(typical data) E-INK SIPIX QR-LPD EC ADT xLCD MEMS Indicators + + o + + - - Watches + o o o o + + Smart Cards + + o o - - - Shelf Labels + + o - - + + Mobile multimedia - o + - - o + E-Books + o + - o + - Newspaper o…+ o + - o + - Signs + o + - + + - Billboard o - o - + + -

Electrophoretic is suitable for many applications but other technologies outperform EP in some markets like signs !

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 63 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays Overview

Introduction

E-Paper Displays & Applications

Flexible Displays & Challenges

Summary

Some pictures etc. are courtesy of the companies named on the picture, others from, e.g., SID, … Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 64 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Videos Of Flexible Displays

Live Presentation

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 65 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

What Does „Flexible‟ Mean ? *: many times

Plastic Conformal Bendable* Rollable* substrate (bent once)

… and foldable*

• Conformable: Bent once in a large radius in production • Bendable: Can be bent in a large radius by the user • Rollable: Can be rolled up in a 5-25 mm radius • Foldable: Can be folded in a radius of < 1 mm

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 68 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Why Flexible Displays ? 1. More robust (30% of smart phone returns show broken display) 2. Thin and light weight as plastic or thin glass is used as substrate 3. Enables new form factors and products 4. Might be cheaper to manufacture (roll-to-roll vs. batch)

1 2

SAMSUNG

3 4

NOKIA

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 69 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Flexible Electronic Systems

Source:ITRI Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 72 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays Reflections on Flat and Curved Displays

… capture light from “everywhere!” Diffuse Neon Spot ceiling lights lights

“Diffuse” illuminance from ceiling or sky is best for reflective displays Single lamp with multiple specular reflections PLASTIC LOGIC

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 74 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

What are the Requirements for „Flexible‟ ? • Substrates have to be thin and light weight

• Display material must be able to work under strain

• Most display technologies need an Active Matrix, but Passive Matrix makes the transition from glass to polymeric substrates much simpler

• Core issues that typically come up: • Glass based displays have - Lifetime manufacturing infrastructure - Keeping the two substrates together - Fabrication • Plastic has some infrastruc- - Flexible interconnects ture, but not (yet) for displays

• What about the electronics system ? • AM on plastic → brick wall !

• What are the new applications, customers … ?

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 75 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays Overview Of Technologies for Flexible Displays

- OLED Reflective Emissive - Transmissive LCD - LED (see § applications)

Electrophoretic Reflective LCDs Other

- Wet (E-INK) - Reflective TN*  - Electro xxx (EC, EL) - In-plane ep - ChLCD - P-INK - Electro-kinetic - PDLCD* *: low power but not all variations are fully bistable

• Not all technologies are listed here like curved projection screens. • Technologies, where major companies are out of business, are not listed.

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 89 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Electrophoretic Wet - Type: E-INK • Principle: Microcapsules with black and white, opposite charged particles • Color by RGB(W) filter, new: “red” as third microcapsules

B/W Monochrome 3 Color “Full Color”

Bendable

Source:E-INK, Plastic Logic

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 90 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Cholesteric LCDs (ChLCD) Flexible color • Principle: Special liquid crystal, no polarizer ChLCD by KENT • Color by dedicated LC reflection

• Reflective RGB stack without color filters etc. • Passive Matrix driving (low cost) but slow update time

Source: ITRI

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 91 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Other Approaches

• Polymer Dispersed LCDs Principle: Standard liquid crystal in droplets, no polarizer, not bistable

• Electrochromic Displays Principle: Color changes by charging

AVESO

• Electroluminescent Displays Flexible sheets used for displays, license plate, knobs, ... Solid state display: ruggedized for in harsh environment (ICE 1) Large area labels by SCHREINER GROUP Sources = names Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 92 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Other Flexible Display Approaches • Electrokinetic (HP) Principle: Particles with charge move in plane, many small reservoirs within visible area

• In-Plane Electrophoretic (CANON, PHILIPS) Principle: Particles with charge move in plane, reservoir at edges

• Photonic Ink (P-ink) (OPTALUX) Principle: Swelling and contacting of a polymer by voltage Sources = names Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 93 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Organic Light Emitting Diode (OLED) • Principle: Light emission by current like LED but organic materials • In mass production since some years • Challenge for lifetime is moisture etc. • Passive Matrix easier to achieve for flexible (see picture ) • Flexible displays in MP • Transparent OLED demonstrated

LG

Rollable demo SONY SAMSUNG

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 94 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Transmissive LCDs

Standard MP AM LCDs can be curved, if - Thin glass and - Flex foil with silicon driver ICs are used. BSI: Curved 40” LCD

However, the backlight has to be adapted 

Advantages of transmissive AM LCDs are: - Easier to manufacture in terms of TFTs as AM - Less requirements on barrier layers for plastic substrates than OLEDs Challenges are backlight, viewing angle, cell gap, … Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 96 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Entertainment Examples of curved LCDs

High volume or small scale customized production ?

AUO BSI

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 97 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Smart Watches / Wearables / Smart Gear

Curved make sense in terms of OLED by LG, UDC ergonomics!

EL

Curved is in favor for watches and smart gear

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 99 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Clock with Curved Display

„Curved as curved can“

Is there a real benefit for the user by the curved display ?

Source: SIPIX Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 100 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Smartphones: Samsung Round & LG Flex Large radius but different orientation of curvature: Many reflections from light sources Application head vs. pocket?

Horizontal, R = 40 cm Vertical, R = 70 cm

SAMSUNG Curved AMOLED

Sources = names Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 102 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Foldable & Rollable Smart Phones

Especially “foldable” with larger benefits for users (small device but large screen for browsing) POLYMER VISION (E-INK) quitted

But: Color is a must ! Sources = names

SAMSUNG YOUM visions: rollable foldable

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 103 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Mobile Applications: , E-Reader, Tablet, …

Main demands: • Multimedia or e-reader • Unbreakable, light weight • Foldable, rollable ! • Benefit for notebook?

Benefit of curved display? Touch slider ?

Samsung YOUM 2013 w. OLED

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 104 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Curved TVs SAMSUNG

First curved OLED TV @ CES 2013. Benefits: Life-like viewing experience for panorama landscapes (feeling surrounded). MP of curved OLED- and LCD-TVs started in 2013

LG Radius ~ 500 cm

Real benefits ? OLED TVs were announced for hanging on the wall. Sources = names Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 105 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Curved TV Benefits

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 106 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays What is that? (captured @ Display Lab)

Reflections of a small 1 W LED on concave curved TV screen

Display: 55", focal length = 2.25 m (measured), radius = 4.5 m (R = 2f; manufacturer: 4.2 m) LED:Blankenbach 1 Watt, / Pforzheim30°, 3,200 Univ. K, / www.displaylabor.de Geometry: small / E light-Paper source / Jan. 2015 distance ~ 4.5 m, observer distance ~ 3 m ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Automotive Applications

Main requirements: DAIMLER • Size > 5” • Wide viewing angle • Seamless integration • Automotive environment

• Design visions become reality

• Niche market compared to CE JDI: Curved (R = 50 cm) 8” WVGA

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 108 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Large Area Flexible Display Applications Signs, e-signage, rooms, … • Signs is large market but is there a need for flexible ?

• E-signage favors color / video

ChLCD by ITRI

E-INK

E-INK

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 110 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Special Case: Semiconductor LEDs Basically not flexible but can be attached to flexible substrates due to small size of individual LED. Advantages: MP LEDs + easy to customize

ICT globe

LED video walls Curved provided by many companies.

Source: V&V, KB Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 111 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Comparison of Flexible Display Technologies

LCD E-Paper OLED

Type Reflective Transmissive Reflective Emissive

Flexibility + + + … ++ +

Image Indoor o ++ o … + ++ Quality Outdoor ++ o ++ o Power consumption + o + o Multimedia – ++ – ++

Mono- Cell gap, Mono- Lifetime, Issues chrome, TFTs (less chrome, critical than TFTs cell gap frontlight OLED)

Overall comparison difficult because of very different application requirements. Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 112 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Flexible Displays – Merits vs. Shortcomings • Advantages + Thin, light weight + Rugged, non-breakable, especially impact stress + Flexible: new freedom of design + Potentially much lower cost (R2R process)

• Shortcomings – Initially more expensive – Initially inferior optical performance – Reduced lifetime compared to glass based displays – Thin substrates must be mechanically protected and supported

Benefits may overweight drawbacks in future !

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 113 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Challenges for Flexible Displays (Short Overview) TFT AM more challenging than PM Bending Radius

- Smaller is more challenging Ambient Light - Bend once easier than often (1,000+ x) … capture light R from “everywhere!” Flexible Rigid

Plastic Substrate Single lamp with multiple - Low temperature processes (TFTs !) specular reflections - OLED lifetime (barrier layer)

- Thin Glass can break, only 1D bending PLASTIC LOGIC

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 114 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Trends : Transparent & Flexible Displays

LCD

Goal: High transparency

OLED

Goal: Plastic substrate, low bending E-Paper LCD radius OLED

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 117 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Market Drivers Of Flexible Displays

Other apps Smartphone, Notebook (wearables, smart gear, Tablet Monitor, TV automotive, e-signage, …)

Thin, light weight, ? unbreakable. Curved TV: marketing New products, Why hot? or technology demo? Vision: new designs, … Notebook: maybe light foldable, rollable weight, unbreakable

Price for foldable Maybe no need, Markets can be Why not? & rollable high cost too small

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 118 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Summary of Flexible Substrates Technologies

Metal Foil Thin Glass Plastics Fabric Unbreakable + – + + Weight – o + + Surface smoothness – + o + (needed for display layers) (planarization) Thermal stability + + – –

Dimensional stability + + – – Chemical durability o + – o Transmission – + o – Barrier layer (OLED) + + – – TCE of Charge Other topics plastic  TFT coupling  OTFT

There are more characteristics to compare. Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 119 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Flexible Displays – Merits vs. Shortcomings • Advantages + Thin, light weight + Rugged, non-breakable, especially impact stress + Flexible: new freedom of design + Potentially much lower cost (R2R process)

• Shortcomings – Initially more expensive – Initially inferior optical performance – Reduced lifetime compared to glass based displays – Thin substrates must be mechanically protected and supported

Benefits may overweight drawbacks in future !

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 120 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays Overview

Introduction

E-Paper Displays & Applications

Flexible Displays & Challenges

Summary

Some pictures etc. are courtesy of the companies named on the picture, others from, e.g., SID, … Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 121 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

E-Paper is Green: Saving Materials & Preserving Nature

Go green

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 122 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Green: Saving Space and Energy with New Displays

From 100 W via 10 W to nearly zero power !

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 123 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

E-Paper Panel Strategies Today Current Target Future Target

Electro-optic Layer B/W Color Moving Picture (reflectivity) (response time)

Back Plane All printed Printed a-Si, p-Si back plane O-TFT incl. drivers (manufacturability)

Planel Flexible (current target will rigid R2R need long time) (manufacturability)

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 124 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Basic Comparison of Professional Display Technologies

LCD E-Paper OLED

Type Reflective Transmissive Reflective Emissive

Size (mass production) 1” … 5” 2” … >100” 1” … 10” 1” … 5”

Image Indoor o ++ o … + ++ Quality Outdoor ++ o ++ o Power consumption + … ++ o ++ o Multimedia – ++ – ++ Flexible o o … + ++ + Relative cost Low Moderate Moderate High Mono- Main issue Reflectance Outdoor Lifetime chrome Overall comparison difficult because of very different application requirements. Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 125 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Summary

E-paper has the potential to revolutionise mobile computing

(Too ?) Many technologies for e-paper today

There are many applications beside e-readers for e-paper displays

To do: color reproduction, switching speed and flexible (AM) substrates

Flexible displays enable new products and roll-to-roll manufacturing

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 126 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays Summary

To do or optimize for flexible: - Substrates SONY - Materials Source: Heikenfeld - Manufacturing

User benefit decides Flexible displays on market success. enable new However flexible products or display technologies enhance features may be profitable in of existing ones niche markets.

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 127 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Case Study / Questions to think about

• Reasons why E-paper will revolutionise mobile computing

• Arguments why this would not happened for many applications

• How can we select (invest) today in the most promising candidates

• Flexibility will give (bi-stable) displays break-through applications

• Flexible technology enables roll-to-roll manufacturing – but what is about cost and benefit for high resolution displays ?

• Compare today‟s notebooks vs. (future) e-readers

• E-Paper applications for the industry

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 128 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Case Study : E-Reader

Like paper but comfort for mobile - Compare price to laptops! reading ? - Business model similar to mobile phones?

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 129 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Case Study : E-Reader

German laws vs. US

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 130 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Case Study : E-Reader

15 cm (6 Zoll) E Ink-Display, optimiert mit geschützter Waveform- und Font- Display Technologie, Auflösung von 600 x 800 Pixel bei 167 dpi, 16 Graustufen Abmessungen 166 mm x 114 mm x 8,7 mm (in cm) Gewicht 170 Gramm Systemanforde Keine, der eReader funktioniert drahtlos und benötigt keinen Computer rungen Geräte- 2 GB intern (ca. 1,25 GB stehen für Nutzerinhalte zur Verfügung) Speicher Cloud-Speicher Unbegrenzt für Amazon-Inhalte Ein vollgeladener Akku hält bei ausgeschalteter Wi-Fi-Funktion bis zu einem Monat, wenn Sie täglich bis zu einer halben Stunde lesen. Mit dauerhaft Akku-Laufzeit eingeschalteter Wi-Fi-Funktion hält er bis zu 3 Wochen. Die Akku-Laufzeit variiert je nach Nutzung, z. B. ob Sie im Kindle-Shop einkaufen, den Browser benutzen oder Inhalte herunterladen. Lässt sich mithilfe des mitgelieferten USB 2.0 Kabels über einen Computer in Ladezeit 3 Stunden voll aufladen. Optionales Netzteil separat erhältlich.

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 131 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Case Study : E-Reader

Unterstützt öffentliche und private Wi-Fi-Netzwerke und Hotspots, die einen folgender Standards nutzen: 802.11b, 802.11g oder 802.11n (im b- oder g- Kompatibilitätsmodus). Kindle unterstützt die Sicherheitstechnologien WEP, Wi-Fi / WLAN WPA und WPA2 mit Kennwortauthentifizierung; er verbindet sich nicht mit WPA- und WPA2-gesicherten Netzwerken mit 802.1X Authentifizierungsmethoden; unterstützt keine Ad-hoc (oder Peer-to-Peer) Wi- Fi-Netzwerke.

USB-Anschluss USB 2.0 (Micro-B USB) Unterstützte Kindle (AZW), TXT, PDF, ungeschützte MOBI, PRC nativ; HTML, DOC, Formate DOCX, JPEG, GIF, PNG, BMP nach Konvertierung.

Kurzanleitung (im Lieferumfang enthalten); Kindle Benutzerhandbuch (auf Dokumentation dem eReader vorinstalliert). Weitere Informationen sind online erhältlich.

1 Jahr Herstellergarantie . 2 Jahre Extragarantie kann für Kunden aus Garantie Deutschland optional von Squaretrade erworben werden. Die Benutzung des Kindle unterliegt der Lizenzvereinbarung und Nutzungsbedingungen.

Lieferumfang Kindle eReader, USB 2.0 Kabel, and Kurzanleitung.

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 132 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Case Study : E-Reader And color ??

E.g. for internet, multimedia, …

Technical Details 7" multi-touch display with IPS (in- plane switching) technology and anti- Display reflective treatment, 1024 x 600 pixel resolution at 169 ppi, 16 million colors. Size (in 7.5" x 4.7" x 0.45" (190 mm x 120 inches) mm x 11.4 mm). Weight 14.6 ounces (413 grams). Up to 8 hours of continuous reading or 7.5 hours of video playback, with wireless off. Battery life will vary Battery Life (AMAZON has announced over based on wireless usage, such as web browsing and downloading the years that they will come content. up with color E-INK display!

Blankenbach / Pforzheim Univ. / www.displaylabor.de / E-Paper / Jan. 2015 133 ET/IT & TI Elektronische Displays : E-Paper & Flexible Displays

Case Study : E-Reader

• Will monochrome e-book readers survive ? (additional device for commuting, travel, etc. as smartphone is a must)

• Will color e-book readers survive with “dedicated” hardware or will they be replace by tablets?

• What is the business model of the future? Hardware, content for various devices, …

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