Trillion Science 04/29/06RC Liang for TsingHua Univ. Toward Flexible and Roll-able Displays/Electronic Paper and Their R2R Manufacturing Processes R.C. Liang Trillion Science Mountain View, CA

Trillion Science 04/29/06RC Liang for TsingHua Univ. From CRT to Flexible Displays & Format Flexible ePaper ~100 years ago ~30 years ago ? ? ~1000 years ago

Trillion Science 04/29/06RC Liang for TsingHua Univ. Worldwide FPD Market

Trillion Science 04/29/06RC Liang for TsingHua Univ. Cost Structure of a 40” LCD TV The material cost accounts for 75% of the total manufacturing cost. ---Information Display, 22(2), p 12 (2006)---

Trillion Science 04/29/06RC Liang for TsingHua Univ. Flexible Display Market to Grow 83.5%/yr

Trillion Science 04/29/06RC Liang for TsingHua Univ. Hitachi ePaper 07/ x440 Recent Developments Fujitsu 07/2005

Trillion Science 04/29/06RC Liang for TsingHua Univ. Recent Developments Magink & Mitsubishi Electric 06/2005 E-ink/Toppan 06/2005 Pull-out, roll-up display 08/2005; e-ink/Philips

Trillion Science 04/29/06RC Liang for TsingHua Univ. Conformal, Wearable, and Rollable Displays demonstrated recently

Trillion Science 04/29/06RC Liang for TsingHua Univ. Definition of Electronic Paper A display with the basic characteristics of printed media:  Compatibility with flexible substrates  No power required to maintain an image (bistability)  Wide viewing angle  Insensitive to ambient lighting and various humidity/temperature conditions. And preferably, -Low manufacturing cost -Low Operating cost -Format Flexibility -Easy Converting

Trillion Science 04/29/06RC Liang for TsingHua Univ. Paper vs. Displays Dot density required in printed media to match the resolution of a 200 ppi display with 24-bit color (IBM)  400 dpi typical 100 ppi of current electronic displays.  inexpensive 2400 dpi printers are now available for home and office uses. As of today, printed Media is still of much higher resolution and lower cost

Trillion Science 04/29/06RC Liang for TsingHua Univ. Technical Challenges for Rollable Displays & Roll-to-Roll Manufacturing General issues: Barrier properties, surface roughness and temperature resistance of substrate Mismatch of thermal expansion coefficients Flexure resistance of the electrodes Flexible Battery For LCDs: Cell gap control during bending/rolling Viewing angle Thickness & Light Management

Trillion Science 04/29/06RC Liang for TsingHua Univ. Flexible Display Technologies Flexible display technologies recently demonstrated may be categorized into three major groups: Those based on liquid crystal technologies such as polymer dispersed liquid crystal ( PDLC ), polymer encased LC, STN, cholesteric LC, ferroelectric LC, bi-stable TN, Microcup LC. Those based on light emitting diode technologies, OLED/PLED/PHOLED, CCM, ECL, and their hybrids. Others such as electrophoretic, gyroelectric, electrochromic, electrodeposition, conducting particles, and liquid powder.

Trillion Science 04/29/06RC Liang for TsingHua Univ. Contrast During Bending/Rolling -Changes of cell gap during bending may be controlled to about 50 nm by using spacers in fixed positions that are aligned with the ITO lines. -Fixing cell gap by microcup structure is a potential solution for roll-to-roll manufacturing of flexible displays with or without polarizers.

Trillion Science 04/29/06RC Liang for TsingHua Univ. Light/Power/Thickness Management Light Guide 100% Lamp Output Lamp Diffuser Reflector TAC Stretched PVA TAC LCD-cell Stretched A plate ( Polarizer Compensation film-1 or WV film) Color Filter TFT 85% 25% 90% um um um TAC um Stretched PVA TAC Polarizer Stretched & coated C plate Compensation film-2 (or WV film) 45% um DBEF (recycle polarized light) 130 um 50% BEF (collect light) 155 um x um ~4% transmitted

Trillion Science 04/29/06RC Liang for TsingHua Univ. Optical Films Currently Used in LCDs About 440um (C) X-plate oe TAC film 80um DBEF layers Diffuser Sheets PEN n= 1.64 n o ~ 1.64 ne~ 1.88 Stretched PEN (A) 3M DBEF Film Isotropic adhesive polarizer (C) X-Plate (D) Fuji Photo WV film WV Film LC Cell WV Film (E) Nippon Oil NH Film Film axis LCP <1um  n=0.236 polarizer ( B) A & C plates (for MVA Mode) polarizer C-plate, (n x =n y >n z) C-plate A-plate, (n x >n y =n z ) VA cell ηXηX ηYηY ηZηZ

Trillion Science 04/29/06RC Liang for TsingHua Univ. 3M DBEF Stacks DBEF layers Diffuser Sheets About 440um oe n o ~ 1.64 ne~ 1.88 PEN n= 1.64 Stretched PEN

Trillion Science 04/29/06RC Liang for TsingHua Univ. Brightness Enhancement Film by UV Curing Paliocolor LC UV curing 1. Stretching o oe Reflector/diffuser depolarize light Polaroid, 3M, Brown Univ. (B) Stretched LC dispersion Nitto, Philips, Reveo, BASF, OCLI, ROLIC, 3M, Charmica (A) Cholesteric LC films Polarizer ¼ Wave plate CLC stacks Backlight Unit Unpolarized light Circular polarized light Linearly Polarized light

Trillion Science 04/29/06RC Liang for TsingHua Univ. LC Coating LC film on carrier; Transfer Lamination or overcoating, if needed. DryingUV Curing Converting (5A) (5B) Brightness Enhancement Film by UV curing of CLC Acrylates (BASF)

Trillion Science 04/29/06RC Liang for TsingHua Univ. Polarizers by Coating TAC Stretched PVA/iodide TAC Polarizer Optiva Areas for future improvements: - Orientation for higher efficiency - Improve environmental stability (w/o protective films) - In-cell coating (not to scale)

Trillion Science 04/29/06RC Liang for TsingHua Univ. Cholesteric LC (Kent Display/Kodak) Homeotropic (transparent) Planar (Bragg Reflecting) Focal Conic Weakly Scattering Kent Display 1. UV induced phase separation of CLC/monomer mixture. Or 2. Pre-encapsulated CLC in binder.

Trillion Science 04/29/06RC Liang for TsingHua Univ. Monodispersed Microcup LCDs Conventional PDLC by UV-induced phase separation 10  m 2  m (l) x 2  m (w) x 1.5  m (p) 3  m (l) x 3  m (w) x 2.5  m (p) Microcup LCD

Trillion Science 04/29/06RC Liang for TsingHua Univ. Flexible Display Technologies Flexible display technologies recently demonstrated may be categorized into three major groups: Those based on liquid crystal technologies such as polymer dispersed liquid crystal (PDLC), polymer encased LC, STN, cholesteric LC, ferroelectric LC, bi-stable TN, Microcup LC. Those based on light emitting diode technologies, OLED/PLED/PHOLED, CCM, ECL, and their hybrids. Others such as electrophoretic, gyroelectric, electrochromic, electrodeposition, conducting particles, and liquid powder.

Trillion Science 04/29/06RC Liang for TsingHua Univ. PHOLED (Universal Display)

Trillion Science 04/29/06RC Liang for TsingHua Univ. Flexible OLED/PLED Printed PLED (DNP) Pioneer

Trillion Science 04/29/06RC Liang for TsingHua Univ. Barrier Properties

Trillion Science 04/29/06RC Liang for TsingHua Univ. - Pioneer: SiON passivation layer - Vitex System Multilayer AlOx/Acrylic system

Trillion Science 04/29/06RC Liang for TsingHua Univ. Flexible Display Technologies Flexible display technologies recently demonstrated may be categorized into three major groups: Those based on liquid crystal technologies such as polymer dispersed liquid crystal (PDLC), polymer encased LC, STN, cholesteric LC, ferroelectric LC, bi-stable TN, Microcup LC. Those based on light emitting diode technologies, OLED/PLED/PHOLED, CCM, ECL, and their hybrids. Others such as electrophoretic, gyroelectric, electrochromic, electrodeposition, conducting particles, and liquid powder. Others such as electrophoretic, gyroelectric, electrochromic, electrodeposition, conducting particles, and liquid powder.

Trillion Science 04/29/06RC Liang for TsingHua Univ. Conducting Particles (e.g. Citala) Radiation curing of particle dispersion in polymer matrix

Trillion Science 04/29/06RC Liang for TsingHua Univ. Rotating Balls (Gyricon Media) ElectroChromic Displays (N’Tera Ltd., Ireland and Uppsala Univ, Sweden)

Trillion Science 04/29/06RC Liang for TsingHua Univ. Microcapsule EPDs (e-Ink) Pull-out, roll-up display 08/2005

Trillion Science 04/29/06RC Liang for TsingHua Univ. Embossin g Roller Adhesive Transparent Conductor Cutter Finished EPD Film 1. Coating 2. Microembossing 3. Filling & Sealing 4. Lamination & Cutting EPD Fluid Transparent Conductor Microcup EPDs (SiPix Imaging) UV

Trillion Science 04/29/06RC Liang for TsingHua Univ. Continuous Filling & Sealing Process Phase separated Sealing material Phase separation Pre- dispersed sealing material hardening Controlling factors: Density Incompatibility Surface tension Viscosity Controlling factors: Density Incompatibility Surface tension Viscosity Seamless sealing may be accomplished in seconds. Phase separation and hardening Sealant material Two-phase Inter-mixing Overcoat sealing layer

Trillion Science 04/29/06RC Liang for TsingHua Univ. EPD Roll Microcup ® PMEPDs Lower Pattern Conductor Film Microcups w EPD fluid Adhesive/Sealing Layer Upper Conductor Film FPC and Driver IC Connectors Microcup ® AMEPDs a-Si TFT ITO/PET Microcup TiO2 particles Sealing/adhesive layer Viewing Side < +10 V Lamination To TFT EP panel Release liner Remove Release

Trillion Science 04/29/06RC Liang for TsingHua Univ. Rollable Microcup® EPDs Integrated by Polymer Vision, Philip

Trillion Science 04/29/06RC Liang for TsingHua Univ. Roll-able Microcup EPDs (SiPix)

Trillion Science 04/29/06RC Liang for TsingHua Univ. Conclusions Technical challenges exist in barrier, substrate, cell gap control, flexure resistance of electrodes, viewing angle, light and thickness management management, and manufacturing processes. Roll-to-roll manufacturing of EPD and other display technologies that are relatively insensitive to environment and cell gap are easier to realize. Plenty of rooms for new comers to play a key role in the technology breakthrough.

Trillion Science 04/29/06RC Liang for TsingHua Univ. Acknowledgement Special thanks to BASF Electronic Materials BU Delta Electronics & Delta Opto CMO About Trillion Science  A Mountain View, CA startup (2005-present) of 19 R&D staffs to develop next generation materials for displays, semiconductors, solar cells and fuel cells.  R.C. Liang, now CEO of Trillion, was the cofounder and inventor of the SiPix Microcup Technologies ( ) and the executive advisor of the BASF Electronic Materials BU (2005) and Delta Electronics (2005-present).

Trillion Science 04/29/06RC Liang for TsingHua Univ. ECD Roll-to-Roll Flexible Solar Cell Akzo Nobel Roll-to-Roll Flexible Solar Cell Temporary Al foil Plastic film Others: Fujitsu, Sharp, Sanyo…etc

Trillion Science 04/29/06RC Liang for TsingHua Univ. Seamlessly Sealed Microcups ® Conductor film (ITO/PET) Conductor film Sealing/Adhesive Microcup Partition Cell gap: 15~30  m.

Trillion Science 04/29/06RC Liang for TsingHua Univ. CCM by Univ. of Cinn.

Trillion Science 04/29/06RC Liang for TsingHua Univ. Electrowetting (by Philips, Cornell Univ, RPI)

Trillion Science 04/29/06RC Liang for TsingHua Univ. Iridigm Digital Paper (A MEMS Based Display)

Trillion Science 04/29/06RC Liang for TsingHua Univ. Electrodeposition Displays (Sony) BridgeStone Liquid Powder