throbber
Part 1: Fundamentals of
`
`Projected-Capacitive
`Touch Technology
`
`Geoff Walker
`
`1
`
`Senior Touch Technologist
`Intel Corporation
`
`June 1, 2014
`
`File Download: www.wa|kermobiIe.comI'l'ouch_Technologies_TutoriaI_Latest_Version.pdf
`
`SID DISPLAY WEEK‘14 V12
`
`

`
`Agenda
`
`°:~ Introduction
`
`oto Basic Principles
`
`oz» Controllers
`
`«:o Sensors
`
`«:0 ITO-Replacement Materials
`
`«:0 Modules
`
`«:0 Embedded
`
`«to Large-Forrnat
`
`«:0 Stylus
`
`«to Software
`
`«:~ Conclusions
`
`v:~ Appendix A: Historical Embedded Touch
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Introduction
`
`°:~ P—Cap History
`
`0.0 P—Cap Penetration
`
`02° P—Cap by Application
`
`°t° Touch User-Experience
`
`File Download: www.walkermobile.comI'|'ouch_Technologies_TutoriaI_Latest_Version.pdf
`
`SID DISPLAY WEEK ‘l4
`
`3
`
`inte|'
`
`Must use exact
`
`capitalization!
`
`

`
`P-Cap History
`
`K Roya Radar
`Establishment
`
`E.A. Johnson
`
`CERN (Bent Stumpe)
`
`Dynapro Thin Films
`(acquired by 3M Touch
`S stems in 2000
`
`Zytronic (first license from
`Ronald Binstead, an
`inventor in the UK)
`
`Visual Planet (second
`license from Ronald
`
`Binstead
`
`Apple
`
`First published application of transparent
`touchscreen (mutual-capacitance p-cap on
`CRT air-traffic control tenninals
`
`Second published application of mutual-
`capacitance p-cap (in the control room of
`the CERN proton synchrotron)
`First commercialization of mutual-
`
`self-capacitive p-cap;
`first commercialization of large-format
`mutual—capacitive p-cap
`Second commercialization of large-format
`self-capacitive p-cap
`
`First use of mutual-capacitive p-cap in a
`consumer electronics roduct the iPhone
`
`‘65
`
`1977
`
`1995
`
`1998
`
`2012
`
`2003
`
`2007
`
`SID DISPLAY WEEK ‘l4
`
`

`
`P-Cap Penetration
`
`% of Units Shipped
`looy
`2.8% 2.4% 1.3%
`0
`
`2.5% 1.2% 0.6% 0.3% 0.3% 0.3% 0.2% 0.2% 0-2%
`
`90% .
`
`80%
`
`70%
`
`60%
`
`50% .
`
`T
`
`T
`
`T
`
`40%
`
`30%
`
`20%
`
`10%
`
`0%
`
`Embedded
`= P-Cap
`
`I Other Technologies
`
`I In-Cell (P-Cap)
`
`T
`
`T
`
`T
`
`IOn-Ce|l(P-Cap)
`
`I Resistive
`
`I P-Cap
`
`T
`
`T
`
`2007A 2008A 2009A 2010A 2011A 2012A 2013A 2014F 2015F 2016F 2017F 2018F
`
`Source: DisplaySearch Touch-Panel Market Analysis Reports 2008-2014
`
`SID DISPLAY WEEK ‘l4
`
`

`
`P-Cap Forecast by Application...1
`(Consumer)
`
`Million Units
`120
`
`I PDA
`
`I Desktop Monitor
`
`I Video Camera
`
`I All-in-one PC
`
`I Portable Game
`
`I Still Camera
`
`I EPD eReader
`
`I Media Player
`
`I Smart Watch
`
`I Navigation Device
`
`I Notebook PC
`
`2012
`
`2013
`
`2014
`
`2015
`
`2016
`
`2017
`
`2018
`
`#2013: Phones = 1.8 Billion Units; Tablets = 447 Million Units
`
`Source: Dispiaysearch Touch—Pane| Market Analysis Report 1Q—2014
`
`SID DISPLAY WEEK ‘14
`
`5
`
`ifieb
`
`

`
`P-Cap Forecast by Application...2
`(Commercial)
`
`Million Units
`8.0
`
`7.0
`
`6.0
`
`5.0
`
`4.0
`
`3.0
`
`2.0
`
`1.0
`
`0.0
`
`2012
`
`2013
`
`2014
`
`2015
`
`2016
`
`2017
`
`2018
`
`#2018: Automobile Monitor = 42 Million Units
`
`Source: Displaysearch Touch—Pane| Market Analysis Report 1Q—2014
`
`SID DISPLAY WEEK ‘14
`
`7
`
`I Education/Training
`
`I Point of Interest
`
`I Ticketing/Check-in
`
`I Casino Game
`
`I Medical Equipment
`
`I ATM Machine
`
`I Office Equipment
`
`I Retail and POS/ECR
`
`I Factory Equipment
`
`

`
`P-Cap Defines the Standard
`for Touch User-Experience
`
`«to Smartphones and tablets have set the standard
`for touch in SEVERAL BILLION consumers’ m
`
`+ Multiple simultaneous touches
`(robust multi-touch)
`+ Extremely light touch (zero force)
`+ Flush surface (“zero-bezel”
`
`’
`
`or “edge-to-edge”)
`
`+ Excellent optical performance
`
`+ Very smooth & fast scrolling
`
`+ Reliable and durable
`
`+ An integral part of the
`device user experience
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Basic Principles
`
`02* Self Capacitive
`
`'3 Mutual Capacitive
`
`~20 Mutual Capacitive Electrode Patterns
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Self-Capacitance
`
`03° Capacitance of a single electrode to ground
`
`+ Human body capacitance increases the capacitance
`of the electrode to ground
`
`+ In a self-capacitance sensor, each electrode is measured
`individually
`
`No Touch CS
`
`Source: The author
`
`SID DISPLAY WEEK ‘14
`
`

`
`The Problem with Self-Capacitance
`
`°2° Touches that are diagonally separated produce
`two maximums on each axis (real points & ghost points)
`
`4 Ghost points = False touches positionally related to real touches
`
`Self Capacitance
`
`Mutual Capacitance
`
`Ghost Points
`
`Source: Atmel
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Self-Capacitance and
`PinchlZoom Gestures
`
`°:~ Use the direction of movement of the points rather
`than the ambiguous locations
`
`X2
`
`X3
`
`X4
`
`Source: The author
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Self-Capacitance Electrode Variations
`
`lllllllllllliiil
`
`'”"‘-V..,_‘11.";_._
`
`IIIIIIIIIIIL
`
`In
`
`II I I IIII I II
`
`20 measurements
`
`5°"'°°= 3'“
`
`20 measurements
`
`+ Multiple separate pads
`in a single layer
`
`+ Rows and columns of electrodes
`in two layers
`
`+ Each pad is scanned
`individually
`
`+ Row & column electrodes are
`scanned in seguence
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Self-Capacitance
`Advantages & Disadvantages
`
`—
`
`«:0 Where it’s used
`
`+ Lower-end smartphones and feature-phones with touch
`
`0 Becoming much less common due to single-layer p-cap
`
`+ In combination with mutual capacitance to increase capability
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Self-Capacitance for Hover
`
`oz» Self-capacitance is used to produce “hover”
`
`behavior in some smartphones (in addition to
`mutual-capacitance for contact-touch location)
`
`+ Also used for automatically detecting glove vs. fingernail vs. skin,
`and for dealing with water on the screen
`
`Source: Panasonic
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Multi-Touch Self-Capacitance
`Using Active Guard Concept...1
`
`«:0 Guarding is a well-known technique for reducing the
`effects of electrical current leakage
`
`Leakage capacitance < 10 aF
`
`source; |=oga|e
`
`1ZI1I1ZZI1
`
`'
`
`5
`
`Active guard
`
`IIIIII I I I
`
`I
`
`/
`
`\\_________
`
`"°"
`
`SID DISPLAY WEEK ‘14
`
`

`
`Multi-Touch Self-Capacitance
`Using Active Guard Concept...2
`
`03° Another contender: zRRo
`
`R
`
`T
`
`v
`
`u
`
`I
`
`‘.
`
`'
`
`0
`
`L
`
`P
`
`/
`
`3D single-touch
`for smartphones
`
`W 3D multi-touch
`I
`for smartphones
`and tablets
`
`T
`
`SID DISPLAY WEEK ‘14
`
`ifieD
`
`

`
`Mutual Capacitance
`
`03° Capacitance between two electrodes
`
`+ Human body capacitance “steals charge” which decreases
`the capacitance between the electrodes
`
`+ In a mutual-capacitance sensor, each electrode intersection
`is measured individually
`
`Projected
`
`-in--u-n-—-_-__
`
`Glass
`
`Sense
`
`Electrode
`
`Electrode
`
`Electrode
`
`Source: The author
`
`SID DISPLAY WEEK ‘14
`
`

`
`Mutual Capacitance
`Electrode Patterns...1
`
`«:0 Rows and columns of
`
`electrodes in two la ersy
`
`«z» In the real world...
`
`+ “Bar and stripe”, also called
`“Manhattan” or “Flooded-X”
`
`(LCD noise self—shie|ding)
`
`Iluuuulr
`
`IIIIIIIIIIIL
`
`lllllllllllliim
`
`11 x 9 = 99 measurements
`
`Source: 3M
`
`I
`
`| I I | I Source:Cypress
`
`X4
`
`10=40
`
`measurements
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Mutual Capacitance
`Electrode Patterns...2
`
`0:0 Interlocking diamond pattern
`with ITO in “one layer” with bridges
`
`4.5 mm t3(pica|
`xxxxxxxxxxxxxxxxx
`xxxxxxxxxxxxxxxxx
`iXf>()(,>()(XX)()()(.[X)(>()(j>()( -
`
`xxxxxxxxxxxxx,‘%xf
`;><j>(,x;x;><:)<[>(f>(,)<lxax x><iXX5<fx._
`
`"“”“”"
`Wire or no
`
`xxxxxxxxxxxxxxxxx
`xxxxxxxxxxxxxxxxx
`xxxxxxxxxxxxxxxxxl
`
`Source: 3M
`
`SID DISPLAY WEEK ‘l4
`
`Source: The author
`
`

`
`More On Mutual Capacitance...1
`
`«to BTW, there isn't just one mutual capacitance...
`
`//V
`
`\\‘
`
`SID DISPLAY WEEK ‘l4
`
`Source: Cypress
`
`

`
`More On Mutual Capacitance...2
`
`°:~ And there are more capacitors than just the Cm’s...
`
`Finger
`Equivalent
`
`Sensing Signal
`
`Source: ELAN, modified by the author
`
`SID DISPLAY WEEK ‘l4
`
`22
`
`

`
`More On Mutual Capacitance...3
`
`——— «
`
`:0 Where it’s used
`
`+ Mid & high-end smartphones, tablets,
`Ultrabooks, AiOs, commercial products
`
`0 Standalone self-capacitive is becoming increasingly rare
`in consumer electronics (except for buttons)
`
`# With “true single-layer” sensors in low-end smartphones
`
`SID DISPLAY WEEK ‘l4
`
`

`
`

`
`Mutual Capacitance
`Electrode Patterns...4
`
`02° And so does this unusual diamond pattern...
`
`4 102, 106, 108, 210
`
`0 Drive (X) electrodes
`
`4 114 & 202
`
`0 Sense (Y) electrodes
`
`4 110
`
`o Bridges
`
`4 120 & 230
`
`o Dummy (floating) ITO
`
`4 200 & 206
`
`0 Optional dummy ITO
`
`4 212
`
`0 Blank (no ITO)
`
`Source: STMicro
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Mutual Capacitance
`Electrode Patterns...5
`
`03° Claimed advantages of this particular
`pattern over traditional interlocking diamond
`
`+ Reduction in sense electrode area reduces LCD noise pickup
`
`+ “Finger projections” (0.1 - 0.2 mm) increase the perimeter of
`interaction between drive and sense electrodes, which
`
`increases sensitivity
`
`+ Linearity is improved due to more uniform coupling across channels
`
`+ Floating separators aid in increasing the fringing fields, which
`increases sensitivity
`
`SID DISPLAY WEEK ‘14
`
`

`
`Mutual Capacitance
`Electrode Patterns...6
`
`»:~ Holy Grail: True single-layer mutual capacitance sensor
`
`0:» “Caterpillar” pattern
`
`O Everybody’s single-
`layer patterns are
`proprietary
`
`+ Requires fine
`patterning, low sheet
`resistance & low
`
`visibility
`
`O Benefits: Narrow
`
`borders, thin stack-
`
`ups, lower cost, can
`reliably handle 2-3
`touches
`
`Source: Synaptics
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Mutual Capacitance
`Electrode Patterns...7
`
`»:~ ELAN’s caterpillar pattern
`
`x1
`
`x2
`
`

`
`Mutual Capacitance
`Electrode Patterns...8
`
`°:~ An alternative true single-layer pattern from ELAN
`
`+ This is a very small portion
`of a much larger sensor
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Controllers
`
`92* Architecture
`
`02° Touch Image Processing
`
`0% Key Characteristics
`
`N Signal-to-Noise Ratio
`
`° Noise Management
`
`Innovation Areas
`
`02° Suppliers
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Mutual Capacitance
`Touch System Architecture
`
`Sense
`E'9¢t"°d95
`
`Analog Front-
`End (AFE)
`
`Analog-
`to-Digital
`Converter
`(ADC)
`
`Digital
`Signal
`Processor
`(osp)
`
`Electrodes
`
`Capacitive Nodes
`
`Host
`
`Interface
`
`Touch Sensor
`
`Touch Controller
`
`Source: The author
`
`+ Making X*Y measurements is OK, but it's better
`to measure the columns simultaneously
`
`+ Controllers can be ganged (operate in a
`master-slave relationship) for larger screens
`
`SID DISPLAY WEEK ‘14
`
`

`
`Touch Image Processing
`
`Raw data including n0iSe
`
`Filtered data
`
`Gradient data
`
`Touch region coordinates
`and gradient data
`
`“1 0 fingers,
`2
`
`sf:
`
`a n
`
`x-7070704 -‘-
`a=9w 333
`x-41729, y-33: saaeen
`
`"
`
`321230
`
`3 others
`
`17
`
`_ fl ;
`:=?90 V8 y=5’O I56960
`
`Source: Apple Patent Application #2006/0097991
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Key Controller Characteristics...1
`
`«to Node count (x channels + y channels)
`
`+ Given typical electrode spacing of 4.5 to 5 mm, this determines
`how large a touchscreen the controller can support (w/o ganging)
`
`«to Scan rate
`
`§ Frames per second (fps) — faster reduces latency for a better UX
`
`+ Windows logo requires 100 fps; Android is unspecified
`
`0:. Signal-to-noise ratio (SNR)
`
`+ More info on upcoming slides
`
`«to Operating voltage & current
`
`+ OEMs continue to request lower-power touchscreen systems
`
`+ Win8 “Connected Standby” is a significant influence
`
`«:0 Internal core (microIDSP)
`
`O Varies from small 8-bit micro to ARM-7 or higher
`
`SID DISPLAY WEEK ‘l4
`
`33
`
`

`
`Key Controller Characteristics...2
`
`03° Number of simultaneous touches
`
`+ Windows Logo requires 5 (except AiO = 2); Android is unspecified
`
`+ Market trend is 10 for tablets and notebooks
`
`«to Support for unintended touches
`
`+ “Palm rejection”, “grip suppression”, etc.
`
`+ Rarely specified, but critically important
`
`+ For a 22" screen, even 50 touches isn’t too many in this regard
`
`do Amount of “tuning” required
`
`4 Never specified — more info on upcoming slide
`
`SID DISPLAY WEEK ‘14
`
`

`
`Signal-to-Noise Ratio (SNR)...1
`
`oz» SNR = Industry-standard performance metric
`
`for p-cap touchscreen systems
`
`§ However, no standard methodologies exist for measuring,
`calculating, and reporting SNR
`
`+ The two components (signal & noise) depend heavily on
`the device under test
`
`«:0 Noise from displays (LCDs & 0LEDs) and from
`USB chargers is spiky - it doesn’t have a normal
`(Gaussian) distribution — and spikes create jitter
`
`4 Yet marketers typically specify SNR in the absence of noise,
`using the RMS noise (standard deviation) of analog-to-digital
`convertors (ADCs)
`
`+ With Gaussian noise, you can multiply the RMS noise by 6 to
`calculate the peak-to-peak noise with 99.7% confidence
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Signal-to-Noise Ratio (SNR)...2
`
`°:~ Typical system (raw ADC data, no digital filters applied)
`
`Source: Cypress
`(modified by the author)
`
`3 2‘
`
`52 8 E
`
`

`
`Signal-to-Noise Ratio (SNR)...3
`
`«:0 SNR of system in previous slide
`
`4 Cfinge, = Mean (Finger) - Mean (NoFinger)
`4 CF"-|ger = 1850 - 813 = 1037
`
`4 CNS (Standard Deviation) = 20.6 counts
`
`4 CNS (Peak-to-Peak) = Max (NoFinger) - Min (NoFinger) +1
`
`4 CNS = 900 - 746 +1 = 155 counts
`
`4 SNR (Peak-to-Peak) = 1037/155 = 6.7
`
`4 SNR (Standard Deviation) = 1037/20.6 = 49.9
`
`4 Highest SNR currently reported by marketer = 70 dB (3,162*)
`
`SID DISPLAY WEEK ‘14
`
`37
`
`inte|'
`
`* Signal amplitude ratio in dB = 20log10 (A1/A0)
`
`

`
`Noise Management...1
`
`«:0 Charger noise is common-mode
`
`+ A smartphone on a desk (not handheld) isn't grounded, so the
`entire phone moves relative to earth ground as it follows the noise
`
`4 A touching finger provides an alternative path to ground, which
`is equivalent to injecting the noise at the finger location
`
`4 The noise signal can be 10X to 100X that of the signal
`generated by the touching finger
`
`svdc
`
`5Vd
`
`C
`
`sva
`
`C
`
`5Vd
`
`“Gnd”
`
`Source: Cypress
`
`‘
`
`I
`
`. I I u
`I
`I
`f
`l
`I I I I I
`
`Can be
`as high
`as 60 V
`p-p for
`222:5;
`
`No common-mode noise
`
`Small common -mode noise
`
`Strong common-mode noise
`
`SID DISPLAY WEEK ‘14
`
`

`
`Noise Management...2
`
`°:~ Examples of charger noise spectra
`
`+ Effect of noise is false or no touches, or excessive jitter
`
`/ Narrow-band noise (charger A)
`\
`
`Wide-band noise (ohager B)
`
`L
`
`200
`
`300
`
`400
`
`Charger Noise Frequency
`
`600 kHz
`
`some: Cymess
`
`1
`
`0
`‘O
`
`a‘
`
`E 8
`
`’
`5 00
`.2
`
`E £
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Noise Management...3
`
`°:~ Variation in common-mode noise spectra in 2
`different chargers at 3 different loads
`
`No load
`
`Load 50%
`
`SID DISPLAY WEEK ‘l4
`
`‘“"‘
`
`Source: Cypress
`
`

`
`Noise Management...4
`
`03° Techniques to combat charger noise
`
`+ Multiple linear and non-linear filters
`
`+ Adaptive selection of the best operating frequency (hopping)
`
`+ Increased drive-electrode voltage
`
`0 Going from 2.7 V to 10 V increases SNR by 4X
`
`+ Many proprietary methods
`
`«to Display noise
`
`+ LCD noise is similar across the display; the high correlation of noise
`signals across all sensor signals allows relatively easy removal
`
`4 Very high noise in embedded touch can require synchronization
`of the touch controller with the LCD driver (TCON)
`
`SID DISPLAY WEEK ‘14
`
`

`
`Controller Innovation Areas
`
`«:0 More information in upcoming slides
`4 Finger-hover
`4 Glove-touch
`
`4 Pressure sensing
`4 Other touch-objects
`4 Faster response (reduced latency)
`4 Adaptive behavior
`4 Water resistance
`
`4 Software integration
`4 Automated tuning
`
`'30 More information later in this course
`
`4 Passive and active stylus support
`
`SID DISPLAY WEEK ‘14
`
`

`
`Finger-Hover...1
`
`«to There are two ways of emulating “mouseover” on
`
`a p-cap touchscreen
`
`§ Hover over something to see it change, then touch to select
`
`§ Press lightly on something to see it change, then press harder
`to select
`
`oz» The industry is moving towards hover because nobody
`has been able to implement pressure-sensing in a way
`
`that works well and that 0EMs are willing to implement
`
`4 Startup: Nextlnput
`
`o Force—sensing using an array of organic transistors where pressure
`
`changes the gate current
`
`+ Startup: zRRo
`
`o Multi-finger hover detection
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Finger-Hover...2
`
`«:0 What can you do with hover?
`
`+ Enlarge small links when you hover over them
`
`+ Make a passive stylus seem to hover like an active stylus
`
`+ Magnify an onscreen-keyboard key as you approach
`rather than after you’ve touched it, or even use a “Swipe”
`keyboard without touching it
`
`+ Preview interactive objects such as an array of thumbnails
`
`+ Use as an alternative to standard proximity detection
`
`4 Use mu|ti—finger gestures for more complex operations
`
`+ And more...
`
`SID DISPLAY WEEK ‘14
`
`

`
`Glove-Touch
`
`02° Can be accomplished by
`adding self-capacitive to
`existing mutual-capacitive
`
`+ Mutual-capacitive provides
`touch location
`
`4 Self-capacitive provides
`proximity sensing
`
`+ Glove-touch causes the finger
`to remain a constant distance
`
`above the screen; proximity
`sensing can detect that without
`the user manually switching
`modes
`
`SID DISPLAY WEEK ‘14
`
`

`
`Pressure Sensing
`
`03° Pressure-sensing is an alternative selection method
`
`+ True absolute pressure-sensing in p-cap doesn't exist today
`
`+ Some (including Microsoft) believe that “touch lightly to view
`choices then press to select” is more intuitive than hover
`
`o It has never been implemented successfully in a mobile device
`
`> Blackberry Storm (2 models!) failed due to terrible implementation
`
`> Nissha/Peratech (QTC) collaboration never made it into mass—production
`
`+ Multiple startups are working on smartphone pressure-sensing
`
`o Nextlnput
`
`) Uses an array of pressure-sensitive organic transistors under the LCD
`
`0 FloatingTouch
`
`> Mounts the LCD on pressure-sensing capacitors made using a 3M material
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Other Touch Objects
`
`oz» You will soon be able to touch with a fine-tipped (2 mm)
`passive stylus, long fingernails, a ballpoint pen, a #2
`pencil, and maybe other objects
`
`+ This is being accomplished through higher signal-to-noise
`(SNR) ratios
`
`o Much of this improvement may come from enhancing the controller
`
`analog front-end in addition to focusing on the digital algorithms
`
`+ This enhancement to the UX will be the end of “finger-on|y” p-cap
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Faster Response
`
`ozo Make touch more natural by reducing latency
`
`4 The shorter the time is between a touch and the response,
`the better the user feels about the touch system
`
`c If an object lags behind your finger when you drag it, or ink lags
`
`behind a stylus when you’re drawing, it doesn’t feel real
`
`0 Latency today is typically 75-100 ms;
`studies have shown that humans
`
`need less than 10 ms for comfort
`
`0 Synaptics has addressed the problem
`by creating a direct path between the
`touch controller and the TCON to
`
`allow limited instant screen updates
`
`o Tactual Labs (startup) has a method
`
`of reducing latency to just a few
`milliseconds
`
`SID DISPLAY WEEK ‘l4
`
`Android
`lag!
`
`Source: Gigaom.com
`
`

`
`Adaptive Behavior: Noise Immunity
`
`»: Adaptive noise-management by N-Trig
`
`SID DISPLAY WEEK ‘14
`
`

`
`Water Resistance...1
`
`«:0 The basic concept is combining self-capacitive and
`mutual-capacitive sensing (again)
`
`Water drops on the screen
`
`source: ELAN
`
`Self Y
`
`SID DISPLAY WEEK ‘l4
`
`50
`
`intel'
`
`Water is not detected
`
`Water is detected in
`
`in self-capacitive mode
`
`mutual—capacitive mode
`
`

`
`Water Resistance...2
`
`oz» A large amount of water with single-touch
`
`15:5ooooooonoouoooooooco7aouoomoooooooooooo:(
`
`lfoazxoooooonnooooooooounooooaoauooooooooooooojt
`
`S°U"3e3ELAN
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Water Resistance...3
`
`«to A large amount of water with two touches
`2
`3
`4
`5
`6
`7
`8
`3
`
`‘
`
`'
`2' I H
`
`MN
`'65")?
`
`‘W-Self Y
`;
`£7;
`
`aoocnoooooneoucomooncowoosnoosooofi
`
`-
`
`«««-n«»===
`
`-a9s5o|IiIm;oooo ouocuaou omo oouof
`"
`,
`(Mk
`LXMJ}
`
`(HI)
`
`sill)
`
`(III?
`
`till.) CIIIJ
`
`'
`
`-
`,
`-
`
`‘MK MIN All
`
`:.
`
`SID DISPLAY WEEK ‘l4
`
`intel
`

`
`:oooc'cooo:anoojouoo'oooo:oooo ooooioooo
`
`oooo
`
`Sou[ce;E|_AN
`
`

`
`Software Integration
`
`«to Make more resources available to the touch controller
`
`+ Run touch algorithms on the GPU instead of the controller micro
`
`o Algorithm-writers can take advantage of much larger resources on
`
`the host device (MIPS and memory)
`
`>
`
`o Algorithmic code is easier and faster to change when it’s in a “driver”
`than when it's in firmware in an ASIC
`
`> Most touch-controller suppliers never change the firmware in the
`touch controller once it ships in a device; N—Trig is the sole exception
`
`0 Cost-reduction by elimination of one micro
`
`> Even more cost reduction for large screens by elimination of slave chips
`
`0 Something similar to this has already been done in NV|D|A’s
`“Direct Touch”, but it hasn’t been widely used in actual devices
`
`SID DISPLAY WEEK ‘14
`
`

`
`Automated Tuning
`
`«:0 For true “touch everywhere”, p-cap has to become
`like resistive: Just slap it on and you’re done
`
`+ We're far from that point today
`
`+ Atmel says that the typical first integration of a p-cap touch-panel
`into a new product takes one full day of tweaking up to 200
`individual parameters
`
`+ That badly needs to be automated so that small commercial
`product-makers have easier access to p-cap
`
`SID DISPLAY WEEK ‘14
`
`

`
`P-Cap Controller Suppliers
`
`03° In order by estimated 2013 revenue
`
`Broadcom A Ie
`
`Ts T°'° 7 ‘3°%’
`"“°°°””‘ 2°’
`ab°“t 85 /" °f
`total revenue
`
`China & Taiwan
`
`FocalTech
`
`ELAN
`
`And a few others...
`+ AMT
`+ Avago
`EET:
`ms + pixel,
`..
`8'8
`Tawvan
`+ Slllcon Labs
`
`+ STMicro
`
`+ Weltrend
`
`SID DISPLAY WEEK ‘14
`
`

`
`02° Substrates
`
`020 Structures
`
`020 Sheet vs. Piece Method
`
`020 More on OGS
`
`020 Glass Strengthening
`
`020 Surface Treatments
`
`020 ITO Index Matching
`
`020 Suppliers
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Sensor Substrates...1
`
`03° ITO film substrates are usually PET‘ or COP2
`
`+ Thickness has dropped from 100 pm to 50 um
`
`+ Lowest practical ITO sheet resistivity is currently ~100 (2/1:
`
`«to ITO glass substrates
`
`+ Standard thickness for GG is 0.33 mm and 0.4 mm
`
`4 Some makers have developed a thinning process (like for LCDs)
`that reduces glass thickness to 0.2 mm
`
`+ Coming and AGC have developed 0.1 mm glass but it hasn’t
`been used in volume sensor production yet
`
`+ Lowest practical ITO sheet resistivity on glass is ~50 0/1:
`
`1 = Polyethylene Terephthalate
`2 = Cyclic Olefin Polymer
`
`SID DISPLAY WEEK ‘l4
`
`

`
`570°C
`
`No known effect
`
`nG
`
`)v
`
`coo$
`
`Thicker
`
`Heavier
`
`ood
`
`Chemical, heat,
`ion-exchange
`
`Sensor Substrates...2
`
`oz» PET film versus glass
`
`Glass Transition Temperature 70°C
`
`Aging Effects
`
`Transparency
`Resolution Capability
`Stacku
`
`Weight
`
`Moisture Resistance
`
`Lamination Yield
`
`Mechanical Strengthening
`
`Yellowing, curling,
`surface deformation
`
`85%
`
`10-30 pm
`Thinner
`
`Lighter
`
`Good
`
`Cost
`
`$ was < lass
`
`SID DISPLAY WEEK ‘14
`
`

`
`Sensor Structures...1
`
`~:~ Sensor structure abbreviations (for reference)
`
`Cover-lass or o lastic or sa o hire
`
`Cover-glass, or sensor-glass with ITO on one side, or
`c lain o lass for film lamination
`
`G G
`
`GG
`
`Cover-lass + one sensor- lass without ITO location
`
`GGG Cover-lass + two sheets of sensor- lass rare
`
`G#
`
`G1 F
`GFF
`
`# = Number of ITO layers on one side of sensor-glass
`G2 = “One Glass Solution” = OGS = SOC = SOL, etc.
`F = Sensor-film with ITO on one side, laminated to glass
`FF = Two sensor-films, laminated to lass
`
`1 = Two ITO layers on one side of sensor-film,
`laminated to glass (also called GF-Single)
`2 = One ITO layer on each side of sensor-film,
`laminated to glass (also called GFxy with metal mesh)
`ITO on one side of substrate (single-sided);
`usually includes metal bridges for Y to cross X
`ITO on both sides of substrate double-sided
`
`F1 = Single-sided sensor-film on top of CF glass;
`T = Transmit (drive) electrodes on TFT glass
`(LG Disp|ay’s hybrid in—cel|/on-cell)
`
`SID DISPLAY WEEK ‘14
`
`59
`
`intel‘
`
`

`
`Sensor Structures...2
`
`03° Glass-only structures
`
`Structure Names
`
`GGG
`
`GG or G-SITO
`
`GG , G-DITO or G1G
`
`OGS or SOC
`
`Comments
`
`Single ITO layer on
`
`Single ITO layer
`
`ITO layer on each
`
`Single ITO layer
`
`each piece of glass;
`Obsolete
`
`with bridges
`
`side of 1 glass; or ITO
`on one side of 2 - lass
`
`with bridges
`
`Example Products
`
`Kindle Fire,
`
` B&N Nook;
`
`Nokia Lumia 800
`
`iPhon&1; iPad-1
`
`(GG); LenovoAiOs
`
`G1G
`
`Google Nexus 4/7;
`
`Xiaomi2;
`
`Nokia Lumia 920
`
`> SITO = Single-sided ITO layer; usually means there’s a bridge
`
`) DITO = Double-sided ITO layer (Apple patent)
`
`> OGS = One Glass Solution (sensor on cover-glass)
`
`> SSG = Simple Sensor Glass (OGS without cover—glass shaping & finishing)
`
`SID DISPLAY WEEK ‘14
`
`intel’
`
`

`
`Sensor Structures...3
`
`°:~ Glass-and-film structures
`
`Structure Names
`
`G1 F
`
`Single ITO layer on
`
`glass; single ITO
`la er on film
`
`Example Products
`
`Many Samsung
`
`products in 2013;
`Microsoft
`
`Surface RT
`
`> Why would a touch-module maker use a sensor structure
`that requires having both glass- and film-handling equipment?
`
`» One reason is that there was a shortage of ITO film in 2013
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Sensor Structures...4
`
`«to Film-only structures
`Structure Names
`
`Comments
`
`Bare glass and two
`single-sided ITO films;
`performance is better
`than GF1
`
`GF2 or DITO-Film
`
`Bare glass and one
`double-sided
`
`Bare glass with true
`single-layer complex
`pattern on film
`
`Apple iPads; next
`iPhone if Apple can’t get
`. ood ield on in—ceIl
`
`l-Vlany |ow—end
`smartphones, especially
`in China
`
`GF Triangle
`Bare glass with true
`single-layer triangle
`pattern on film
`(e.g., "backgammon")
`Low-end products with
`"gesture touch’, not
`multi-touch
`
`> Single-layer caterpillar pattern is used to support “rea|” multi-touch with 2-3
`touches, typically in a smartphone (that's not enough touches for a tablet)
`
`> Sing|e—layer backgammon pattern is used to support “gesture touch” on
`low-end devices, i.e., the ability to detect pairs of moving fingers but not
`always resolve two stationary touches
`
`SID DISPLAY WEEK ‘14
`
`62
`
`intel
`
`

`
`Sensor Structures...5
`
`°:~ Why do touch-module makers choose one structure
`over another?
`
`+ Transmissivity
`
`+ Thickness & weight
`
`4 Border width due to routing
`
`# Cost & availability of ITO film or deposition
`
`4 Lamination experience & yields
`
`+ Existing equipment and/or method experience
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Sensor Structure by Application
`
`Smartphones
`
`Tablets & Notebooks
`
`A||—in-Ones
`
`GF1/Sinle-La er
`
`Data based on DispIaySearch's “Q1-2014 Quarterly Touch-Panel
`Market Analysis Report”, with adjustments by the author
`
`SID DISPLAY WEEK ‘14
`
`

`
`Sheet vs. Piece Method...1
`
`(Wintek Sheet Example - OGS)
`
`SID DISPLAY WEEK ‘14
`
`55
`
`Source: Wintek
`
`

`
`Sheet vs. Piece Method...2
`
`(Wintek Piece Example - Discrete)
`
`SID DISPLAY WEEK ‘l4
`
`55
`
`Source: Wintek
`
`

`
`More On OGS
`
`oz» One-Glass Solution (OGS)
`
`4 Also called “touch on |ens” (TOL), “sensor on cover” (SOC),
`“direct patterned window” (DPW) and many other names
`
`4 Advantages
`
`o Eliminates a fourth sheet of glass (G-DITO), making the end-product
`
`thinner and lighter
`
`0 Competitive weapon against embedded touch from LCD suppliers
`
`4 Disadvantages
`
`o Requires close cooperation with cover-glass makers, or increased
`vertical integration (preferable)
`
`o Yields are lower (more complex operations)
`
`0 Bendable cover glass can affect touch performance
`
`0 Harder to shield touchscreen from LCD noise
`
`4 Note: There is no generic name (yet) for touch sensors built on the
`cover-glass without direct ITO deposition (“OGS-type”)
`
`SID DISPLAY WEEK ‘14
`
`57
`
`intel
`
`

`
`Glass Strengthening
`
`oz» Heat strengthened
`
`+ Less-rigorous version of fully tempered; does not “dice” when
`
`broken; 2X as strong as standard glass
`
`0:» Fully tempered
`
`§ Uses heat; requires glass > 3 mm, so not used for consumer
`touchscreens; glass “dices” when broken (think auto windows);
`4X to 6X as strong as standard glass
`
`«:0 Chemical strengthened (CS)
`
`4 Uses ion-exchange in a salt bath; best for glass < 3mm; glass does
`NOT “dice” when broken; 6X to 8X as strong as standard glass
`
`«:0 High ion-exchange aluminosilicate glass
`
`0 6X to 8X as strong as standard glass (same as CS glass)
`
`4 Coming Gori||a®, Asahi Dragontrai|""', Schott XensationT""
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Sensor Surface Treatments...1
`
`oz» Historically most common treatment is anti-glare (AG)
`
`+ Changes specular reflection into diffuse reflection
`
`+ Used mostly for commercial & enterprise, not consumer (“g|ossy”)
`
`+ Three methods, roughly equal cost
`
`0 Chemical etching
`
`0 Application of sol-gel containing silica particles
`
`o Mechanical abrasion
`
`0 Level of anti-glare can be very little to a lot
`
`03° Anti-fingerprint (AF) treatment is rapidly growing
`
`+ Many different forms (spray-on, rub-on, sputter, etc.); also
`called “anti-smudge” (AS)
`
`0 Demand is increasing
`
`+ Cost is dropping (currently ~$8.50/m2)
`
`SID DISPLAY WEEK ‘l4
`
`59
`
`

`
`Sensor Surface Treatments...2
`
`oz» Anti-reflection (AR) treatment is still a problem
`
`4 Reduces specular reflection to range of 2% to 0.4%
`
`4 Durability is typically < 1 year
`
`4 |t’s expensive (currently ~$34.50/m2)
`
`4 Yet it’s really important for outdoor viewing, particularly of
`consumers’ glossy screens (ideal is AF+AR = ~$43/m2)
`
`~30 Other coatings are available but less common
`
`4 Anti-corruption (allows permanent Sharpie ink to be wiped off)
`
`4 Anti-microbial/anti-bacteriaI (AM/AB, for healthcare applications)
`
`4 Hard coating (can be made up to 9H for glass-like anti-scratch)
`
`4 Anti-stiction (reduces finger-sticking friction)
`
`4 Anti-crack coating (increases durability at lower cost than Gorilla
`glass; uses atomic layer deposition [ALD])
`
`SID DISPLAY WEEK ‘l4
`
`

`
`ITO Refractive-Index Matching
`
`03° Reduce the reflectivity of ITO by compensating for the
`difference in index of refraction of ITO vs. glasslPET
`
`~:~ Limited to 2 layers on PET; more can be used on glass
`
`5 Alternating layers of material with low and high refractive index
`
`+ Layer thicknesses (typically between ‘A and % of the wavelength
`of light) are chosen to produce destructive interference in reflected
`light, and constructive interference in transmitted light
`
`no (Rl = ~2.o)l
`
`TiO2 (RI = 2.43)T
`
`SiO2 (RI = 1.45)
`
`or PET (RI = 1.65)
`
`Source: The author
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Sensor Suppliers
`
`oz» Many touch-module makers manufacture their
`
`own sensors
`
`+ The remainder are made by the following companies,
`in order by estimated 2013 revenue
`
` — Jaan
`
`A,,dat,eastmo,e
`, Laibao(C,,i,,a,
`
`jna
`
`mm
`
`SID DISPLAY WEEK ‘l4
`
`

`
`ITO-Replacement Materials
`
`9:9
`
`9:9
`
`9:9
`
`9:9
`
`9:9
`
`9:9
`
`‘9
`
`'|ver Nanowires
`
`arbon Nanotubes
`
`onductive Polymers
`
`SID DISPLAY WEEK ‘l4
`
`

`
`ITO Replacements...1
`
`«to Why replace ITO?
`4 Costly to pattern & needs high temperature processing
`4 Highly reflective (IR = 2.6) & tinted yellow; brittle & inflexible
`4 NOT because we’re going to run out of it!
`
`«to Replacement material objectives
`4 Solution processing (no vacuum, no converted LCD fab)
`4 Better performance than ITO (transmissivity & resistivity)
`4 Lower material & process cost than ITO
`
`«:0 Five replacement candidates
`4 Metal mesh
`
`4 Silver nanowires
`
`4 Carbon nanotubes
`
`4 Conductive polymers
`4 Graphene
`
`SID DISPLAY WEEK ‘l4
`
`

`
`ITO Replacements...2
`
`~30 ITO-replacement materials are having a definite
`market impact - 11% in 2014!
`
`4 See the latest IHS market report on non-ITO films
`Hon ll J lllm «Market ihdlt‘ by him lyue (2014!
`
`Nomofilm
`11*
`
`i
`
`*
`
`a
`
`0 Ag halide is simply
`another method of
`
`making a silver mesh,
`so the mesh total is
`
`85% vs. 15% for
`
`nanowire
`
`+ The value is performance and cost
`
`0 Both unit cost and CAPEX
`
`SID DISPLAY WEEK ‘14
`
`

`
`Metal Mesh...1
`
`oz» Metal mesh is shipping in touchscreens, and it’s
`looking very promising!
`
`~:~ Brief history of first-movers
`
`O MNTech in Korea was the first to ship metal-mesh at the
`end of 2012 — but their factory burned down
`
`4 Atmel (partnered with CIT in the UK) was the second to ship metal-
`mesh (XSense T”) for a smartphone and a 7" tablet in 1H-2013
`
`4 FujiFi|m started production of their silver-halide-based
`metal-mesh product in 2Q—2013
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Metal Mesh...2
`
`4-5 mm sense electrode (bottom surface)
`
`\
`
`_—
`
`’
`
`\-
`
`Photo by Unipixel,
`annotation by
`the author
`
`.
`
`'
`
`SID DISPLAY WEEK ‘14
`
`4-6 pm wide
`conductors
`
`with spacing
`
`of 100-400 um
`
`4-5 mm
`
`drive
`
`electrode
`
`(top surface)
`
`Intentional
`
`gaps in lines
`
`i@
`
`

`
`Metal Mesh...3
`
`oz» Metal mesh has significant advantages
`
`+ Patterning via roll-to-roll printing allows both operating and
`capex cost to be very low — it’s going to beat both Iitho and laser!
`
`0 Electrodes and border connections are printed simultaneously,
`
`which allows borders as narrow as 3 mm (typically 9 mm with ITO)
`
`+ Sheet resistivity is much lower than ITO (under 10 ohmslsquare)
`
`o Reduces p-cap charge time, which allows larger touchscreens
`
`4 Transparency is better than ITO
`
`4 Mesh pattern creates electrical redundancy, which improves yields
`
`+ Highly flexible — bend radius typically 4 mm
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Metal Mesh...4
`
`°:~ 0-film is the “800-pound gorilla” of metal mesh!
`
`+ Largest touch-module maker in China, #3 globally
`
`+ Like “the TPK of film”; innovative and aggressive
`
`source:0-film
`
`oz» New roll-to-roll printing method
`
`+ “Hybrid printing” or “micro-imprinting”
`
`Cross-section of
`
`embedded metal line
`
`Source:O—fIlm
`
`Impressions
`\
`
`Sflver nan°'
`Partide
`
`UV cure
`A
`
`Source: The author
`
`SID DISPLAY WEEK ‘l4
`
`

`
`Metal Mesh...5
`
`oz» O-film technical details
`
`+ Additive process with little waste
`
`4 < 2 pm line width
`
`+ < 10 (2/1:
`
`4 Randomized mesh design (one method of eliminating moirés)
`
`§ Top surface of embedded metal line is blackened & sealed
`
`+ Embedded metal reduces haze and eliminates peel-off
`
`+ Producing > 1.5M touch sensors per month (size not stated)
`
`~30 O-film’s success makes visible a developing aspect of
`
`the ITO-replacement business
`
`+ Avertical|y—integr

This document is available on Docket Alarm but you must sign up to view it.


Or .

Accessing this document will incur an additional charge of $.

After purchase, you can access this document again without charge.

Accept $ Charge
throbber

Still Working On It

This document is taking longer than usual to download. This can happen if we need to contact the court directly to obtain the document and their servers are running slowly.

Give it another minute or two to complete, and then try the refresh button.

throbber

A few More Minutes ... Still Working

It can take up to 5 minutes for us to download a document if the court servers are running slowly.

Thank you for your continued patience.

This document could not be displayed.

We could not find this document within its docket. Please go back to the docket page and check the link. If that does not work, go back to the docket and refresh it to pull the newest information.

Your account does not support viewing this document.

You need a Paid Account to view this document. Click here to change your account type.

Your account does not support viewing this document.

Set your membership status to view this document.

With a Docket Alarm membership, you'll get a whole lot more, including:

  • Up-to-date information for this case.
  • Email alerts whenever there is an update.
  • Full text search for other cases.
  • Get email alerts whenever a new case matches your search.

Become a Member

One Moment Please

The filing “” is large (MB) and is being downloaded.

Please refresh this page in a few minutes to see if the filing has been downloaded. The filing will also be emailed to you when the download completes.

Your document is on its way!

If you do not receive the document in five minutes, contact support at support@docketalarm.com.

Sealed Document

We are unable to display this document, it may be under a court ordered seal.

If you have proper credentials to access the file, you may proceed directly to the court's system using your government issued username and password.


Access Government Site

We are redirecting you
to a mobile optimized page.





Document Unreadable or Corrupt

Refresh this Document
Go to the Docket

We are unable to display this document.

Refresh this Document
Go to the Docket