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New forms of displays: when will they become economically feasible?
 

New forms of displays: when will they become economically feasible?

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Three dimensional (3D) liquid crystal displays (LCDs) and new forms of displays such as OLED- and holographic-based ones continue to become economically feasible. these slides document the ...

Three dimensional (3D) liquid crystal displays (LCDs) and new forms of displays such as OLED- and holographic-based ones continue to become economically feasible. these slides document the improvements in these displays that are making them economically feasible and the impacts they may have on new applications. The falling cost of displays is being driven by the benefits from increasing the size of the substrate and production equipment for them, by finding better materials for OLED displays, and by improvements in lasers and ICs for holographic displays.

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  • We start with existing forms of lighting and displays and move towards new forms of lighting and displays
  • LCDs are great but they are very complex. Can they be simplified and improved? Are there other ways beyond the replacement of the cold cathodefluorescent light with white LEDs?
  • We start with existing forms of lighting and displays and move towards new forms of lighting and displays
  • We start with existing forms of lighting and displays and move towards new forms of lighting and displays
  • When someone sees a trend, they add their name to it. But they will probably never become as famous as Gordon Moore.
  • The size of LCD substrates were increased by about 4 times in change from 1st generation to 5th generation LCD substrate equipment. We are now at Generation 10
  • Production of generation 7.5 panels (with generation 7.5 equipment) was just starting in 2008. Firms are now implementing generation 10 panels and equipment.
  • Subsequent generations of equipment are very large. Notice the size of the humans in the pictures.
  • The capital cost per area output of LCDs falls as the size of the substrates (and production equipment) are increased. the area increased by 3.7 times while the capital costs only rose by 2.37 times as we moved from Gen 5 to Gen 7.5.
  • This data is for one type of LCD manufacturing equipment, called dry etch equipment. The productivity of the equipment (square meters per hour-$) rose about 8 times (2.7 to 23) as firms moved from Gen II to Gen VI.
  • Anyone who visits consumer electronic stores knows that the price of LCD TVs continue to rapidly fall. Much of these price reductions are due to the increases in the scale of LCD substrates and equipment.
  • Nevertheless, there are some ups and downs over time.
  • We start with existing forms of lighting and displays and move towards new forms of lighting and displays
  • One way to do 3D LCDs is with “time-sequential” and active 3D glasses
  • Improvements in the LCD’s frame rate have been gradually achieved for many years in order to improve image quality
  • These improvements in the LCD’s frame rate are also gradually making 3D LCDs technically and economically feasible.
  • Another approach is auto-stereoscopic displays. They do not require glasses, which many people do not like
  • For auto-stereoscopic, improvements in pixel density are needed. Firms have been also making these improvements over many years also in order to improve image quality.
  • But many additional improvements in pixel density are needed before auto-stereoscopic displays become technically (and economically) feasible.
  • Other factors (in this case standardization and digitization)are also making 3D displays economically feasible.
  • We start with existing forms of lighting and displays and move towards new forms of lighting and displays
  • We talked about OLEDs for lighting earlier. They can also be used in displays and they are cheaper to process than are LCDs.
  • Luminosity per Watt is relevant for both lighting and displays.
  • Here is one problem that firms need to solve before OLEDs can be used as displays in televisions and other electronic products.
  • We start with existing forms of lighting and displays and move towards new forms of lighting and displays
  • We start with existing forms of lighting and displays and move towards new forms of lighting and displays
  • Think of Obi Wan Kenobi. He was presented as a holographic image in star wars
  • When will these “components” become cheap enough for holographic systems to become economically feasible?
  • Their cost is falling primarily because the costs of light sources, holographic media, and transmission systems (i.e., the Internet) are getting cheaper.
  • Lasers (light source) are a key component in a holographic system. When will their costs fall to the extent that the holographic systems become economically feasible?

New forms of displays: when will they become economically feasible? New forms of displays: when will they become economically feasible? Presentation Transcript

  • WHEN WILL NEW TYPES OF DISPLAYS BECOME ECONOMICALLY FEASIBLE AND THUS BEGIN TO DIFFUSE? 5TH SESSION OF MT5009 A/Prof Jeffrey Funk Division of Engineering and Technology Management National University of Singapore For information on other technologies, see http://www.slideshare.net/Funk98/presentations
  • Objectives  What are the important dimensions of performance for displays and their higher level systems?  What are the rates of improvement?  What drives these rapid rates of improvement?  Will these improvements continue?  What kinds of new systems will likely emerge from the improvements in displays?  What does this tell us about the future?
  • Session Technology 1 Objectives and overview of course 2 Two types of improvements: 1) Creating materials that better exploit physical phenomena; 2) Geometrical scaling 4 Semiconductors, ICs, electronic systems 5 MEMS and Bio-electronic ICs 6 Nanotechnology and DNA sequencing 7 Superconductivity and solar cells 8 Lighting and Displays (also roll-to roll printing) 9 Human-computer interfaces 10 Telecommunications and Internet 11 3D printing and energy storage This is Part of the Tenth Session of MT5009
  • As Noted in Previous Session, Two main mechanisms for improvements  Creating materials (and their associated processes) that better exploit physical phenomena  Geometrical scaling  Increases in scale  Reductions in scale  Some technologies directly experience improvements while others indirectly experience them through improvements in “components” A summary of these ideas can be found in 1) forthcoming paper in California Management Review, What Drives Exponential Improvements? 2) book from Stanford University Press, Technology Change and the Rise of New Industries
  • Both are Relevant to Displays  Creating materials (and their associated processes) that better exploit physical phenomena  Creating materials that better exploit the phenomena for LCDs OLEDs and other displays  Geometrical scaling  Increases in scale: larger substrates/production equipment  Reductions in scale: thinner materials  Some technologies directly experience improvements while others indirectly experience them through improvements in “components”  Better displays lead to better electronic systems
  • From the first session. What is the future of displays? How big will these displays be? And how will we interact with them?
  • Will We Use Our Hands i.e., Gesture InterfaceC Or something else?
  • How About Our Homes? What will they be Like?
  • Another View of Future Displays  http://www.youtube.com/watch?v=6Cf7IL_eZ3 8  http://www.youtube.com/watch?v=jZkHpNnXL B0  Can you write down all the applications that you see
  • Some of the applications in the Videos  Photovoltaic glass, Touch screen displays on closets, in cars, phones, tablets, auto windows, tables, walls (classrooms), 3D displays, in middle of air, in forest, augmented reality  PV glass, mirror, refrigerator, counter table, autos (GPS), MRT maps, retail clothing, eBook readers
  • Outline  Liquid Crystal Displays (LCDs)  Cost reductions from increases in scale of LCD substrates (and production equipment)  3D LCD displays  Organic light emitting diode (OLED) displays  Electronic paper  Holographic displays
  • Composition of LCD Panels http://www.ercservice.com/learning/what-is-tft-lcd.html
  • Major components of LCD TV CCFL Backlit LCD TV CCFL Backlight Diffusers To ensure a uniform brightness across panel Polarizer To ensure that the image produced is aligned correctly LCD Panel An LCD panel is made up of millions of pixels filled with liquid crystals arranged in grid, which open and shut to let the backlight through and create images Antiglare Coating Provides a mirror-like finish, making the backlight appear brighter Display Screen One current challenge for LCD TVs: Replace this layer (cold cathode fluorescent light) (78.6 mm) with white- light LEDs (29.9 mm)
  • “LED Television”  Not really an LED television  An LCD television that is backlit by white LEDs  Lower energy costs, higher contrast, variety of advantages  But can’t make television only from LEDs because different color LEDs require different materials and those materials cannot be placed on the same substrate (at least currently)
  • TFT LCDs Continue to Improve Source: AUOSource: OLED Summit Preview, San Francisco, September 27-29 Barry Young, Young Market Research, February 18, 2013
  • Outline  Liquid Crystal Displays (LCDs)  Cost reductions from increases in scale of LCD substrates  3D LCD displays  Organic light emitting diode (OLED) displays  Electronic Paper  Holographic displays
  •  Nishimura’s Law:  The size of LCD substrate grows by a factor of 1.8 every 3 years, doubles every 3.6 years (large panels are cut into appropriate sizes for electronic products)  Less than half the time for IC wafers to double in size (7.5 years)  Odawara’s Law:  Costs fall by 22-23% for doubling in cumulative production  Kichihara’s Law: every three years  Power consumption decreases by 44%  Panel thickness and weight are reduced by one-third  Number of bits needed per screen increases fourfold Display Panel Trends – towards larger and cheaper panels Source: http://metaverseroadmap.org/inputs.html, US Display Consortium (USDC)
  • http://www.economist.com/node/21543215 Source: Television Making: Cracking Up, Economist, January 21st, 2012, p. 66
  • Increases in Scale of LCD Substrates (and also IC Wafers, Solar Substrates)  Equipment costs per area of output fall as size of equipment is increased, similar to chemical plants  For chemical plants  Cost is function of surface area (or radius squared)  Output is function of volume (radius cubed)  Thus, costs increase by 2/3 for each doubling of equipment capacity  For LCD Substrates, IC Wafers, and Solar Substrates  Processing, transfer, and setup time (inverse of output) fall as area of substrate increases since entire area can be processed, transferred, and setup together
  • Another Benefit from Large Panels is Smaller Edge Effects Panel Equipment Effect Effects: the equipment must be much wider than panel to achieve uniformity Ratio of equipment to panel width falls as the size of the panel is increased
  • Increases in LCD Substrate Size Source: www.lcd-tv-reviews.com/pages/fabricating_tft_lcd.php
  • Scale of photolithographic aligners (upper left), sputtering equipment (top right), and mirrors for aligners (lower left) for LCD equipment Source: http://www.canon.com/technology/ canon_tech/explanation/fpd.html
  • http://www.electroiq.com/articles/sst/print/volume-50/issue-2/features/cover-article/scaling-and-complexity-drive- lcd-yield-strategies.html
  •  We can also see the falling cost of LCDs in the falling price of LCD TVs, albeit some of the cost reductions are coming from the falling costs of ICs
  • Source: Bing Zhang, Display Search, Flat Panel TV Cost Analysis & Panel Supply-Demand , May 20, 2008
  • Outline  Cathode Ray Tube  Liquid Crystal Displays (LCDs)  Cost reductions from increases in scale of LCD substrates  3D LCD displays  Organic light emitting diode (OLED) displays  Electronic Paper  Holographic displays
  • Time-Sequential 3D with active 3D Glasses Sources for these slides: Adapted from published paper in Technology and Society by Ng Pei Sin and myself
  • Improvements in Frame-Rate are Occurring 0 50 100 150 200 250 300 1970s 1995 2008 2010 CRT LCD OLED/Plasma  Increased frame-rate of content approaches Critical Flicker Fusion point (where higher frame rate has no perceived benefit) – 60Hz.  Increase frame rate gives smoother, flicker-free motion, especially in high-action videos  Increased Frame-rate of Display  Reaches 120Hz; surpasses critical flicker fusion point  Surplus enables implementation of Time-sequential 3D without compromising improved frame rate of content  Improved LCD frame-rate due to improvement in Liquid Crystal structure, reduced cell- gap, and improved methods to shorten liquid crystal response time 120Hz - Minimum screen frame-rate for „flicker-free‟ Time-sequential 3D Frameperseconds(Hz) Display Frame-Rate
  • Improvements in Frame Rate Increase the Economic Feasibility of Time Sequential 3D  Improvement in Liquid Crystal response time enable:  High frame-rate in LCD display and in active 3D glasses  Economical  Estimated cost of adding 3D to LCD display range from 10% to 30% the cost of panel  Falling costs from larger substrate size can offset these higher costs  But glasses are a big disadvantage……….
  • Auto-Stereoscopic Displays Does not require special 3D glasses Panel pixels are divided into two groups one for left-eye images another for right-eye images A filter element is used to focus each pixel into a viewing zone In order to view television from different places in the room, multiple viewing zones are needed
  •  Improvements in photolithographic equipment enable increases in pixel density  lags resolution in ICs by many years  Sometimes called Kitahara’s Law, improvements of about 4 times occur every 3 years  These increases in pixel density  Enable high definition television  But will exceed the resolution of our eyes  Thus, these increases can be used to assign different pixels  to right and left eye and  to different “viewing” zones Increases in Pixel Density, i.e., Resolution
  •  At least128 million pixels/sq inch are needed  8.3 million pixels needed for high-definition TV  at least eight viewing zones needed to accommodate head movements  each viewing zone needs two sets of pixels  8.3 x 8 x 2 = 128  Best pixel density at Consumer Electronics Show in 2011 was 8.3 million pixels/sq inch  If pixel density continues to increase four-times every three years, technical feasibility in 2017  As for economic feasibility, this depends on incremental cost of the higher densities. If the incremental cost is small, they will probably become economically feasible before 2020. Auto-Stereoscopic Displays
  • But not much diffusion  Not enough content?  Not enough interest in 3D?  Real question is whether such content can be easily created
  •  Standardization and digitalization ease handling, storing and presentation of 3D videos  Standardization reduces complexity and cost of having to produce 3D contents for multiple competing formats  Digital 3D formats build from MPEG-4 video compression with Multiview Video Coding (MVC) encoding “Historical Progression of Media”, From: Three-Dimensional Television: Capture, transmission, Display. By Haldun M. Ozaktas, Levent Onural Other Factors Should Enable New Content: Standardization and Digitization of Video
  • Other Factors Should Enable Better Content: Better graphic processors http://www.behardware.com/articles/659-1/nvidia-cuda-preview.html “NVIDIA® TESLA® GPU COMPUTING”, Nvidia, 2010, http://www.nvidia.com/docs/IO/43395/tesla-brochure-12-lr.pdf Improved Graphics processing unit (GPU) enables: More MPEG4 video compression Rendering of more realistic computer animation (more polygon count and motion control points) Rendering of 3D models for stereoscopic video for 3D displays Enable realistic stereoscopic computer animation good enough for cinema screens presentation, increasing contents in 3D
  • Outline  Cathode Ray Tube  Liquid Crystal Displays (LCDs)  Cost reductions from increases in scale of LCD substrates  3D LCD displays  Organic light emitting diode (OLED) displays  Electronic Paper  Holographic displays
  • Another Option for Displays is an OLED  OLED: Organic Light Emitting Diode  Made of organic (Carbon based) materials that emit light when electricity runs through them  Multiple colors can be roll printed onto a substrate, making them potentially cheaper than that of LCDs  Similar situation with organic solar cells  Construction of OLED  Substrate, Anode  Conductive layer, Emissive layer  Cathode
  • OLEDs also have fewer Layers than LCDs and thus potentially less expensive LCD  Complex structure  Passes through light and thus requires separate light source and color filters OLED  Simple structure  Makes its own light
  • Many of them are Flexible
  • Light emitting electrochemical cells http://www.oled- info.com/tags/technical- research/frontplane/roll-roll
  • http://deviceguru.com/euro-project- slashes-flexible-display-costs/ Light emitting electrochemical cells http://www.oled- info.com/tags/technical- research/frontplane/roll-roll
  • Flexibility Comes from New Materials (e.g., organic ones and Thinner Ones Moving to polymers requires low permeation rates, higher transparencies, and low cost.
  • Returning to OLEDs: Advantages in Response Time, Viewing Angle, Grey Scale Units AMOLED CCFL LED Edge LED Full Difference Luminance cd/m2 None Brightness cd/m2 Power Contrast Ratio (CR) 1000:1 5000:1 6M:1 Dark Images Ambient Contrast Ratio @ 125 Lux ~1000:1 >2,000:1 >2,000:1 >2,000:1 High Lux Black Levels cd/m2 <0.001 0.8 0.1 0.05 Dark Images Viewing Angles CR 100% 3D Response Time ms 0.001 5 3 3 Fast Moving Gray Scale Performance All Gray Scales Movies Frame Rate Hz None 42" Power Consumption W 30 ~120 ~80 ~60 15 Lifetime hrs to 1/2 luminance 50K to 100K ~60K ~70K ~70K Initial LCD Differential Aging Yes Strength Image Sticking Some Strength Form Factor mm 2 5 3 5 Thinner >240 Poor Lower Gray Scales Minor None TFT LCD Same OLED ~1.5X Brighter 20:1 Source: YMR Source: OLED Summit Preview, San Francisco, September 27-29 Barry Young, Young Market Research, February 18, 2013
  • OLEDs Still Lag LEDs in Efficiency Subsequent improvements have occurred (see slides on lighting)
  • • Average life span of about 30,000 hours of viewing, half of LCD TVs 60,000 hours • Blue OLEDs degrades faster than other colors – bringing color balance issues (14,000 vs. 46,000 to 230,000 for red and green) • Thus OLED displays are given blue tint to offset degradation in blue color • Can these problems be solved? • Do OLEDs have a future for some displays? Source: http://www.differencebetween.info/node/707 Another Problem for OLEDs in TVs is Lifespan Source: http://www.hdtvinfo.eu/news/hdtv-articles/oled-tv-estimated- lifespan-shorter-then-expected.html (2008 data)
  • Another Problem is High Price/Cost, but falling 0 50 100 150 200 250 300 350 400 450 500 2009 2010 2011 2012 2013 2014 2015 ASP(US$) 0% 5% 10% 15% 20% 25% 30% 35% 40% 45% 50% PricePremium 32" 1080p CCFL 32" 1080 LED Edge 32" 1080 LED Back 32" OLED 1920 x 1080 OLED Premium vs. Edge OLED Premium vs. Back Source: OLED Summit Preview, San Francisco, September 27-29 Barry Young, Young Market Research, February 18, 2013
  • Costs Fall as Substrate Sizes get Bigger 2007 730x920 2011 Source: OLED Summit Preview, San Francisco, September 27-29 Barry Young, Young Market Research, February 18, 2013
  • New Techniques Required to Scale Process  Making finely patterned sub- pixels with small molecule material requires use of vacuum thermal evaporation using a fine metal mask  Size limits are defined the sagging of the mask  To achieve > 200 ppi, AMOLEDs utilize Pentile technology, which reduces pixel size from 3 sub- pixels to 2 sub-pixels/pixel. To scale beyond ½ 4th Gen, VTE must be changed from positioning the substrate horizontally to holding vertically as implemented by Tokki, Ulvac, Sunic and AMAT  New approaches include the use of CNT by Unidym and nanowires by Cambrios Source: OLED Summit Preview, San Francisco, September 27-29 Barry Young, Young Market Research, February 18, 2013
  • Other Patterning Options Being Tried  Alternative approaches include:  Polymers and small molecule in solution which can be printed  Laser induced thermal imaging (LITI) as developed by 3M and SMD  Eliminating patterning by using white material with a color filter  The most likely for the Gen 5.5 is vertically held substrates  Beyond Gen 5.5 some form of printing will be required  Ink Jet – Panasonic, Epson  Slot – DuPont  Roll to roll process – VTT, Fraunhofer Source: OLED Summit Preview, San Francisco, September 27-29 Barry Young, Young Market Research, February 18, 2013
  • Many Believe Roll-to Roll Printing will Lead to Dramatically Lower Costs Vacuum deposition of metals, dielectrics, & semiconductors 5μ Multiple mask levels imprinted as single 3D structure Patterning completed w/ wet & dry processes deposition imprint etch deposit spin resist align/expose develop strip/clean etch deposit etchimprint etch mask Conventional Photo-Lithography SAIL http://www.hpl.hp.com/techreports/2011/HPL-2011-152.pdf (Roll printing)
  • A Roll of Rolled OLEDs http://deviceguru.com/euro-project-slashes-flexible-display-costs/ Konica is constructing a flexible OLED lighting R2R fab with a monthly capacity of 1 million panels. Production will start in fall of 2014 http://www.oled-info.com/tags/technical- research/frontplane/roll-roll
  • Outline  Cathode Ray Tube  Liquid Crystal Displays (LCDs)  Cost reductions from increases in scale of LCD substrates  3D LCD displays  Organic light emitting diode (OLED) displays  Electronic Paper  Holographic displays
  • LCD + Full color - Harder on the eyes + Can display video (movies) - Takes more power (battery doesn’t last as long) + Backlit, so you can read in the dark - Hard to read outdoors or Early e-Ink - Black & white + Easy on the eyes; like paper - Can’t display full video + Takes very little power (battery lasts longer) - Can’t be read in the dark (like a regular book) + Easy to read outdoors, the more light the better E-Ink has advantages for reading
  • That Become Obvious When You Look at this Picture
  • Improvements in E-ink Electrophoretic Displays Color is now available E Ink Vizplex 1 E Ink Vizplex 2 E Ink Pearl E Ink Triton E Ink Spectra E Ink Carta Announc ement Year 2006 2007 2010 2010 2013 2013 Cost $70 (estimated ) Based on Sory prs 500: $350 $60 (Estimated ) Based on Sony prs 505: $300 $30.5 (2011) Sony prs T1: $150 $26 Based on Sory pr-t2: $130 Color/ Greyscale 4-level gray scale 8 level gray scale 16 levels of gray 16 shades of gray, 4096 colors 2-bit (B/W/R) Contrast 7:1 10:1 10:1 15:1 15:1 Refresh Rate • 1200ms • 500ms for 1 bit mode • 740ms for grayscale • 260 ms for 1-bit mode • 600 ms for grayscale • 120 ms for 1 bit mode • 120ms - 980ms, • 120 ms Resolutio n •170 dpi 600 × 800 •170 dpi • 600 × 800 •Up to 300 dpi 600x800 •200 dpi •768x1024 •(212 ppi) 1024 x •> 300 dpi •768x102
  • And Costs of Color Displays are Falling 7” diagonal display has 0.15 cm2 area $426 per m2, much less than LCD
  • Will this make Wall Displays Economically Feasible?
  • This idea began in December 2011 when Dave Vondle, one of the founders of Central Standard Timing (CST), taped an E-Ink display (electronic paper) around his wrist and said, "I want a watch like this." And so his wish was granted. The CST-01, the thinnest watch in the world, is less than 1mm thick and weighs less than 5 pennies.
  • build a stretchy mesh with electronics on thin islands connected by springy bridges print mesh onto thin plastic which holds the entire mesh together Source: MT5016 group presentation in 2012
  • core technology deployed to allow conformal coupling to the human body all on an ultrathin patch that mounts onto the skin like a temporary tattoo digital health - moderate development cycle - high growth potential - white space opportunity modular system with onboard sensing, processing, power and communication Source: MT5016 group presentation in 2012
  • Outline  Cathode Ray Tube  Liquid Crystal Displays (LCDs)  Cost reductions from increases in scale of LCD substrates  3D LCD displays  Organic light emitting diode (OLED) displays  Electronic Paper  Holographic displays
  • Holographic Systems  Present a real 3D image  LCD-based 3D systems present an “illusion” of three dimensions  Time-Sequential 3D with active 3D Glasses  Auto-Stereoscopic Displays  Holographic Systems present a real 3D image and thus one that can be more aesthetically appealing
  • Hologram in Star Wars
  • A Better Hologram in Total Recall
  • How About a Hologram for a Phone Key Pad? If it is a Hologram?
  • A Little Different – But How about Projecting a Display onto ones Hand? This can be done with a Pico-Projector in a Samsung Phone http://www.engadget.com/2010/02/15/samsung-beam-halo-hands-on/
  • This was done in Total Recall
  • Back to Holograms……..
  • Source: MT5009 group in 2011
  • Looking at Light Source and Holographic Media in more Detail: The Film/Media Records both the Reference and Object Beams http://www.holostar.com/Frame1.html
  • Source: MT5009 group in 2011
  • Source: MT5009 group in 2011
  •  When might such a system become technically and economically feasible for some application and some set of users?
  • Conclusions and Relevant Questions for Your Projects (1)  New displays continue to emerge and experience improvements  New materials that better exploit the relevant physical phenomena (e.g., materials for OLEDs that have higher luminosity per Watt or longer lifetime)  Falling costs from increases in the scale of substrates and production equipment  Improvements in components for holographic displays  Improvements in frame rate and pixel density for 3D displays
  • Conclusions and Relevant Questions for Your Projects (2)  How many further improvements are likely to occur?  When will their costs become low enough or performance high enough to be economical for specific applications?  Can we identify those applications, the order in which they will become economical, and the specific needs of each application?  What about higher-level systems; can we identify ones that might become economically feasible due to improvements in displays and other “components”?  What kinds of analyses can help us answer