`(12) Patent Application Publication (10) Pub. No.: US 2009/0219257 A1
`FREY et al.
`(43) Pub. Date:
`Sep. 3, 2009
`
`US 20090219257A1
`
`(54) TOUCH SCREEN SENSOR
`
`(75) Inventors:
`
`Matthew H. FREY, Cottage Grove,
`MN (US); Lijun Zu, Minneapolis,
`MN (US); Edward S. Hagermoser,
`Lancaster, MA (US)
`Correspondence Address:
`3M INNOVATIVE PROPERTIES COMPANY
`PO BOX 33427
`ST. PAUL, MN 55133-3427 (US)
`(73) Assignee:
`3M Innovative Properties
`Company
`12/393,185
`
`(21) Appl. No.:
`
`(22) Filed:
`
`Feb. 26, 2009
`Related U.S. Application Data
`
`(60) Provisional application No. 61/032,269, filed on Feb.
`28, 2008, provisional application No. 61/032,273,
`
`
`
`filed on Feb. 28, 2008, provisional application No.
`61/085,496, filed on Aug. 1, 2008, provisional appli
`cation No. 61/085,764, filed on Aug. 1, 2008.
`
`Publication Classification
`
`(51) Int. Cl.
`(2006.01)
`G06F 3/04
`(52) U.S. Cl. ......................................... 345/173;977/811
`
`ABSTRACT
`(57)
`A touch screen sensor includes a visible light transparent
`Substrate and an electrically conductive micropattern dis
`posed on or in the visible light transparent substrate. The
`micropattern includes a first region micropattern within a
`touch sensing area and a second region micropattern. The first
`region micropattern has a first sheet resistance value in a first
`direction, is visible light transparent, and has at least 90%
`open area. The second region micropattern has a second sheet
`resistance value in the first direction. The first sheet resistance
`value is different from the second sheet resistance value.
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`Fig. 6
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`PANASONIC EX1012, page 006
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`70
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`S
`60
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`as E
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`5 40
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`1O
`Position along bar (mm)
`Fig. 13
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`40
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`PANASONIC EX1012, page 007
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`A1
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`HHE HE
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`Fig. 15d
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`Fig. 15e
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`Mesh with regions
`7a and 7b in wedge N
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`p
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`Continuous ITO
`Coating in Wedge
`(same overall shape)
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`30
`20
`1O
`Position along bar (mm)
`Fig. 16
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`40
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`PANASONIC EX1012, page 009
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`Fig. 22
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`72 \ln(\)YN (IS/
`&Sea A&1
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`Conductor Trace Width (um)
`Fig. 24
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`Fig. 26
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`PANASONIC EX1012, page 014
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`2
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`Fig.
`28
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`Oo
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`706
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`726
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`740
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`734
`O2
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`732
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`730
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`736
`704
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`Fig. 29
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`PANASONIC EX1012, page 017
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`US 2009/0219257 A1
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`Sep. 3, 2009
`
`TOUCH SCREEN SENSOR
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`0001. This application claims the benefit of U.S. Provi
`sional Application Nos. 61/032,269, filed Feb. 28, 2008, the
`disclosure of which is incorporated by reference herein in its
`entirety: 61/032,273, filed Feb. 28, 2008, the disclosure of
`which is incorporated by reference herein in its entirety:
`61/085,496, filed Aug. 1, 2008, the disclosure of which is
`incorporated by reference herein in its entirety; and 61/085,
`764, filed Aug. 1, 2008, the disclosure of which is incorpo
`rated by reference herein in its entirety.
`
`BACKGROUND
`0002 Touchscreen sensors detect the location of an object
`(e.g. a finger or a stylus) applied to the Surface of a touch
`screen display or the location of an object positioned near the
`Surface of a touch screen display. These sensors detect the
`location of the object along the Surface of the display, e.g. in
`the plane of a flat rectangular display. Examples of touch
`screen sensors include capacitive sensors, resistive sensors,
`and projected capacitive sensors. Such sensors include trans
`parent conductive elements that overlay the display. The ele
`ments are combined with electronic components that use
`electrical signals to probe the elements in order to determine
`the location of an object near or in contact with the display.
`0003. In the field of touchscreen sensors, there is a need to
`have improved control over the electrical properties of the
`transparent touch screen sensors, without compromising
`optical quality or properties of the display. A transparent
`conductive region of a typical touch screen sensor includes a
`continuous coating of a transparent conducting oxide (TCO)
`Such as indium tin oxide (ITO), the coating exhibiting elec
`trical potential gradients based on the location or locations of
`contact to a Voltage source and the overall shape of the region.
`This fact leads to a constraint on possible touch sensor
`designs and sensor performance, and necessitates Such mea
`Sures as expensive signal processing electronics or placement
`of additional electrodes to modify the electrical potential
`gradients. Thus, there is a need for transparent conductive
`elements that offer control over electrical potential gradients
`that is independent of the aforementioned factors.
`0004. There is an additional need in the field of touch
`screen sensors that relates to flexibility in the design of elec
`trically conductive elements. The fabrication of touch screen
`sensors using patterned transparent conducting oxides (TCO)
`such as indium tin oxide (ITO) often places limitations on
`conductor design. The limitations relate to a constraint caused
`by patterning all of the conductive elements from a transpar
`ent sheet conductor that has a single value of isotropic sheet
`resistance.
`
`BRIEF SUMMARY
`0005. In one aspect, the present disclosure relates to touch
`screen sensors having a transparent Substrate and a micropat
`terned conductor (typically metal) of specified pattern geom
`etry to achieve high optical quality. In general, optical quality
`can be expressed in terms of visible light transmittance, haze,
`and conductor visibility, as determined observing the conduc
`tor as it assembled in the touch screen sensor with unaided
`eyes. The geometry of the micropatterned conductor can be
`defined with parameters such as, but not limited to, the width
`
`of the conductor traces (sometimes referred to as “lines”)
`used for the micropattern, the density of the lines, and the
`uniformity of the density of the lines.
`0006. In a first embodiment for a touch screen sensor
`having good optical quality, the touch screen sensor, com
`prises a visible light transparent Substrate; and an electrically
`conductive micropattern disposed on or in the visible light
`transparent Substrate. The micropattern has a conductor trace
`width of about DX+0.5 in units of micrometers; and an open
`area fraction between about 95-X% and 99.5%, where
`0sXs4.5. In another embodiment, the touch screen sensor
`of has an open area fraction between about 98.5-(2.5X-3.
`5)% and 99.5-(X-3.5)% wherein 0sXs3.5. In another
`embodiment, the touch screen sensor has a haze value of less
`than 10%, preferably less than 5%, and visible light transmit
`tance greater than 75%, preferably greater than 85%. In
`another embodiment, the conductor trace width of the touch
`screen sensor is less than about 6 micrometer and having a
`pitch of less than about 300 micrometer. In another embodi
`ment, the conductor trace of the touch screen sensor has a
`thickness of less than about 500 nanometers. In another
`embodiment, the pitch is about 1 mm to 4 mm, with a con
`ductor width less between 3 and 10 microns.
`0007. In another aspect, present disclosure relates to touch
`screen sensors having varying sheet resistance.
`0008. In a first embodiment for a touch screen sensors
`having varying sheet resistance, the sensor includes a visible
`light transparent Substrate and an electrically conductive
`micropattern disposed on or in the visible light transparent
`Substrate. The micropattern includes a first region micropat
`tern within a touch sensing area and a second region micro
`pattern. The first region micropattern has a first sheet resis
`tance value in a first direction, is visible light transparent, and
`has at least 90% open area. The second region micropattern
`has a second sheet resistance value in the first direction. The
`first sheet resistance value is different from the second sheet
`resistance value.
`0009. In another embodiment for a touch screen sensors
`having varying sheet resistance, the sensor includes a visible
`light transparent Substrate and an electrically conductive
`micropattern disposed on or in the visible light transparent
`Substrate. The micropattern includes a first region micropat
`tern within a touch sensing area, the first region micropattern
`having an anisotropic first sheet resistance, being visible light
`transparent, and having at least 90% open area.
`0010. In another embodiment for a touch screen sensors
`having varying sheet resistance, the sensor includes a visible
`light transparent Substrate and an electrically conductive
`micropattern disposed on or in the visible light transparent
`Substrate. The micropattern includes a first region micropat
`tern within a touch sensing area and a second region micro
`pattern. The electrically conductive micropattern has metallic
`linear electrically conductive features with a thickness of less
`than 500 nanometers and a width between 0.5 and 5 microme
`ters. The first region micropattern has a first sheet resistance
`value in a first direction between 5 and 500 ohm per square, is
`visible light transparent, and has between 95% and 99.5%
`open area (or in another embodiment even 99.9% open area,
`or even 99.95% open area). The second region micropattern
`has a second sheet resistance value in the first direction. The
`first sheet resistance value is different from the second sheet
`resistance value.
`0011. In a further embodiment for a touch screen sensors
`having varying sheet resistance, the sensor includes a visible
`
`PANASONIC EX1012, page 018
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`Sep. 3, 2009
`
`light transparent Substrate and an electrically conductive
`micropattern disposed on or in the visible light transparent
`Substrate. The micropattern includes a first region micropat
`tern within a touch sensing area. The electrically conductive
`micropattern includes metallic linear electrically conductive
`features having a thickness of less than 500 nanometers and a
`width between 0.5 and 5 micrometers. The first region micro
`pattern has an anisotropic first sheet resistance with a differ
`ence in sheet resistance values for orthogonal directions of a
`factor of at least 1.5, is visible light transparent, and has
`between 95% and 99.5% open area.
`0012. In a further embodiment, a touch screen sensor is
`described, the touch screen sensor comprising a visible light
`transparent Substrate; and a touch-sensitive electrically con
`ductive micropattern disposed on or in the visible light trans
`parent Substrate; wherein the micropattern includes conduc
`tive traces with width between about 1 and 10 micrometers.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`0013 The invention may be more completely understood
`in consideration of the following detailed description of vari
`ous embodiments of the invention in connection with the
`accompanying drawings, in which:
`0014 FIG. 1 illustrates a schematic diagram of a touch
`screen sensor 100:
`0015 FIG. 2 illustrates a perspective view of a conductive
`visible light transparent region lying within a touch screen
`sensing area;
`0016 FIG. 3 illustrates a process for creating microcon
`ductors using UV laser curing of a conductive ink;
`0017 FIG. 4 illustrates a gravure printing process for cre
`ating microconductors;
`0018 FIG. 5 illustrates a cross section view of microrep
`licated channels filled with conductive material;
`0019 FIG. 6 illustrates a finger capacitively coupling with
`microreplicated channels filled with conductive material;
`0020 FIG. 7 illustrates patterns of microconductors pro
`duced on a flexible substrate, useful for producing touch
`Sensors;
`FIG. 8 illustrates parallel microconductors printed
`0021
`on a flexible web material in the downweb direction;
`0022 FIG. 9 illustrates a section of the flexible material
`from FIG. 8 having additional interconnecting conductors
`added;
`0023 FIG. 10 illustrates a cross section of an example of a
`matrix touch sensor constructed from two layers of the mate
`rials from FIG. 9;
`0024 FIG. 11 illustrates the conductor micropattem for
`one embodiment of the touch screen sensor;
`0025 FIG. 12 illustrates a portion of the conductor micro
`pattern illustrated in FIG. 3, the portion including a conduc
`tive mesh with selective breaks for modulating the local sheet
`resistance as well as a larger feature in the form of a contact
`pad;
`0026 FIG. 13 illustrates a modulation in resistance along
`the horizontal mesh bars given in FIG. 3, created by selective
`breaks in the contiguous mesh;
`0027 FIG. 14 is a circuit diagram that approximates the
`properties of the conductor micropattern illustrated in FIG.3,
`where capacitive plates are separated by resistive elements;
`0028 FIG. 15 illustrates the conductor micropattern for
`one embodiment of the touch screen sensor, the micropattern
`including regions labeled 15a-15e with different sheet resis
`
`tance created in part by selective breaks in the electrically
`conductive micropattern mesh;
`(0029 FIGS. 15a-15e each illustrate a portion of the vary
`ing conductor micropattern illustrated in FIG. 15:
`0030 FIG. 16 illustrates the distribution of resistance per
`unit length along the long axis of the wedge-shaped transpar
`ent conductive region having regions 15a and 15b therein, as
`compared with the resistance per unit length for a similarly
`shaped region comprising only a uniform transparent con
`ducting oxide, ITO;
`0031
`FIG. 17 illustrates the arrangement of layers that are
`laminated together to form one embodiment of the touch
`screen sensor, an X-Y grid type projected capacitive touch
`Screen Sensor,
`0032 FIG. 18 illustrates the conductor micropattern for
`the X-layer or the Y-layer of an embodiment of the touch
`screen sensor according to FIG. 17:
`0033 FIG. 19 illustrates a portion of the conductor micro
`pattern illustrated in FIG. 10, the portion including a visible
`light transparent conductive mesh contacting a larger feature
`in the form of a contact pad, as well as electrically isolated
`conductor deposits in the space between the mesh regions;
`0034 FIG. 20 illustrates the conductor micropattern for
`the X-layer or the Y-layer of another embodiment of the touch
`screen sensor according to FIG. 9;
`0035 FIG. 21 illustrates a portion of the conductor micro
`pattern given in FIG. 12, the portion including a visible light
`transparent conductive mesh contacting a larger feature in the
`form of a contact pad, as well as electrically isolated conduc
`tor deposits in the space between the mesh regions;
`0036 FIG. 22 illustrates the conductor micropattern for
`the X-layer or the Y-layer of another embodiment of the touch
`screen sensor according to FIG. 17; and
`0037 FIG. 23 illustrates a portion of the conductor micro
`pattern given in FIG. 22, the portion including a visible light
`transparent conductive mesh contacting a larger feature in the
`form of a contact pad, as well as electrically isolated conduc
`tor deposits in the space between the mesh regions.
`0038 FIG. 24 illustrates a graph to reflect optical quality
`of the touchscreen sensor, the graph being a plot of Percent of
`Open Area vs. conductor trace width (in micrometers), with
`Region 3 being good optical quality that can be used for a
`touch screen sensor, Region 2 being better in optical quality
`as compared to Region 2, and Region 1 having the best optical
`quality of the three regions. Percent of Open Area is used
`interchangeably with open area fraction herein.
`0039 FIG. 25 and FIG. 26 illustrate scanning electron
`photomicrographs of the geometry for the hexagonal mesh
`(sometimes referred to as “hex’ mesh) and square mesh that
`are characteristic of Examples 6 through 40. The light shade
`lines in each image represent the pattern of the metal conduc
`tor and the dark area represents the substrate used in the
`Examples.
`0040 FIGS. 27, 27a, and 27b illustrate various portions of
`a first patterned substrate;
`004.1
`FIGS. 28, 28a, and 28b illustrate various portions of
`a second patterned Substrate;
`0042 FIG. 29 illustrates a projected capacitive touch
`screen transparent sensor element constructed from the first
`and second patterned substrates of FIGS. 27 and 28.
`0043. The figures are not necessarily to scale. Like num
`bers used in the figures refer to like components. However, it
`will be understood that the use of a number to refer to a
`
`PANASONIC EX1012, page 019
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`component in a given figure is not intended to limit the com
`ponent in another figure labeled with the same number.
`
`DETAILED DESCRIPTION
`0044. In the following description, reference is made to
`the accompanying set of drawings that form a parthereofand
`in which are shown by way of illustration several specific
`embodiments. It is to be understood that other embodiments
`are contemplated and may be made without departing from
`the scope or spirit of the present invention. The following
`detailed description, therefore, is not to be taken in a limiting
`SSC.
`All scientific and technical terms used herein have
`0.045
`meanings commonly used in the art unless otherwise speci
`fied. The definitions provided herein are to facilitate under
`standing of certain terms used frequently herein and are not
`meant to limit the scope of the present disclosure.
`0046. Unless otherwise indicated, all numbers expressing
`feature sizes, amounts, and physical properties used in the
`specification and claims are to be understood as being modi
`fied in all instances by the term “about.” Accordingly, unless
`indicated to the contrary, the numerical parameters set forthin
`the foregoing specification and attached claims are approxi
`mations that can vary depending upon the desired properties
`sought to be obtained by those skilled in the art utilizing the
`teachings disclosed herein.
`0047. The recitation of numerical ranges by endpoints
`includes all numbers within that range (e.g. 1 to 5 includes 1.
`1.5, 2, 2.75, 3, 3.80, 4, and 5) and any range within that range.
`0048. As used in this specification and the appended
`claims, the singular forms “a”, “an and “the encompass
`embodiments having plural referents, unless the context
`clearly dictates otherwise. As used in this specification and
`the appended claims, the term 'or' is generally employed in
`its sense including “and/or unless the context clearly dictates
`otherwise.
`0049. As used herein, “visible light transparent” refers to
`the level of transmission being at least 60 percent transmis
`sive to at least one polarization state of visible light, where the
`percent transmission is normalized to the intensity of the
`incident, optionally polarized light. It is within the meaning
`of visible light transparent for an article that transmits at least
`60 percent of incident light to include microscopic features
`(e.g., dots, squares, or lines with minimum dimension, e.g.
`width, between 0.5 and 10 micrometers, or between 1 and 5
`micrometers) that block light locally to less than 80 percent
`transmission (e.g., 0 percent); however, in Such cases, for an
`approximately equiaxed area including the microscopic fea
`ture and measuring 1000 times the minimum dimension of
`the microscopic feature in width, the average transmittance is
`greater than 60 percent.
`0050. The present disclosure relates to touch screen sen
`sors with electrical and optical properties that are engineered
`through design of conductor micropatterns comprised
`therein. There are several advantages that are created for
`touch screen sensors by the incorporation of the conductor
`micropatterns described herein. In some embodiments, the
`transparent conductive properties within a transparent con
`ductive region are engineered to control the electrical poten
`tial gradient within the touch sensing region during use. This
`leads to simplicity of signal processing electronics and, for
`Some touch screen sensor types simplicity in the design of (or
`elimination of the need for) additional conductor patterns that
`would otherwise be needed for electrical potential gradient
`
`(electrical field) linearization. In some embodiments, the
`electrical properties of the touch screen sensors described
`herein are designed to generate a controlled electrical poten
`tial gradient along a transparent sensor element. E.g., the
`electrical properties are designed to create a linear electrical
`potential gradient along a particular direction within a trans
`parent conductive region, the overall shape of which would
`ordinarily lead to a non-linear gradient if a standard transpar
`ent conductor material was used (e.g., continuous ITO coat
`ing). In some embodiments, the electrical properties are
`designed to create a level of non-linearity of electrical poten
`tial gradient for a transparent conductive region that is greater
`than that which would be present within a transparent con
`ductive region of the same shape but comprised of a standard
`transparent conductor material (e.g., continuous ITO coat
`ing). In more detail, for a rectangular capacitive touch screen
`comprising a contiguous transparent sheet conductor in the
`form of a micropatterned conductor with electrical connec
`tions made to the corners of the sensing area, the linearity of
`electrical potential gradient (and uniformity of electric field)
`across the sensing area in the vertical and horizontal direc
`tions can be improved by engineering the area distribution of
`sheet resistance values and anisotropy in Such a way as to
`distribute the field more uniformly. In other embodiments, the
`sensor includes conductor elements comprised of the same
`conductor material at the same thickness (i.e., height), but
`with different effective sheet resistance by virtue of micro
`patterning. E.g., in some embodiments, the same conductor
`material at the same thickness (i.e., height) is used to generate
`conductive traces that define a first micropattern geometry,
`leading to a first level of sheet resistance in a transparent
`conductive region, and conductive traces that define a second
`micropattern geometry, leading to a second level of sheet
`resistance in a second transparent conductive region. This
`disclosure also allows for improved efficiency and resource
`utilization in the manufacture of transparent display sensors,
`e.g. through the avoidance of rare elements such as indium for
`Some embodiments, e.g. embodiments based on micropat
`terned metal conductors.
`0051. The disclosure further relates to contact or proxim
`ity sensors for touch input of information or instructions into
`electronic devices (e.g., computers, cellular telephones, etc.)
`These sensors are visible light transparent and useful in direct
`combination with a display, overlaying a display element, and
`interfaced with a device that drives the display (as a “touch
`screen” sensor). The sensor element has a sheet like form and
`includes at least one electrically insulating visible light trans
`parent Substrate layer that Supports one or more of the fol
`lowing: i) conductive material (e.g., metal) that is mesh pat
`terned onto two different regions of the substrate surface with
`two different mesh designs so as to generate two regions with
`different effective sheet resistance values, where at least one
`of the regions is a transparent conductive region that lies
`within the touch-sensing area of the sensor; ii) conductive
`material (e.g., metal) that is patterned onto the Surface of the
`Substrate in a mesh geometry so as to generate a transparent
`conductive region that lies within the touch sensing area of the
`sensor and that exhibits anisotropic effective sheet resistance;
`and/or iii) conductive material (e.g., metal) that is patterned
`onto the Surface of the Substrate in a mesh geometry within an
`effectively electrically continuous transparent conductive
`region, the geometry varying within the region so as to gen
`erate different values of local effective sheet resistance in at
`least one direction (e.g., continuously varying sheet resis
`
`PANASONIC EX1012, page 020
` IPR2021-01115
`
`
`
`US 2009/0219257 A1
`
`Sep. 3, 2009
`
`tance for the transparent conductive region), where the region
`lies within the sensing area of the touch sensor.
`0052. The sensing area of a touch sensor is that region of
`the sensor that is intended to overlay, or that overlays, a
`viewable portion of an information display and is visible light
`transparent in order to allow viewability of the information
`display. Viewable portion of the information display refers to
`that portion of an information display that has changeable
`information content, e.g. the portion of a display "screen” that
`is occupied by pixels, e.g. the pixels of a liquid crystal display.
`0053. This disclosure further relates to touch screen sen
`sors that are of the resistive, capacitive, and projected capaci
`tive types. The visible light transparent conductor micropat
`terns are particularly useful for projected capacitive touch
`screen sensors that are integrated with electronic displays. As
`a component of projected capacitive touchscreen sensors, the
`visible light transparent conductive micropattern are useful
`for enabling high touch sensitivity, multi-touch detection, and
`stylus input.
`0054 The two or more different levels of sheet resistance,
`the anisotropy of the sheet resistance, or the varying level of
`sheet resistance within a transparent conductive region can be
`controlled by the geometries of two-dimensional meshes that
`make up the transparent micropatterned conductors, as
`described below.
`0055 While the present invention is not so limited, an
`appreciation of various aspects of the invention will begained
`through a discussion of the examples provided below.
`0056 FIG. 1 illustrates a schematic diagram of a touch
`screen sensor 100. The touch screen sensor 100 includes a
`touch screen panel 110 having a touch sensing area 105. The
`touch sensing area 105 is electrically coupled to a touch
`sensor drive device 120. The touch screen panel 110 is incor
`porated into a display device.
`0057 FIG. 2 illustrates a perspective view of a conductive
`visible light transparent region 101 that would lie within a
`touch sensing area of a touch screen panel, e.g., touch sensing
`area 105 in FIG. 1. The conductive visible light transparent
`region 101 includes a visible light transparent substrate 130
`and an electrically conductive micropattern 140 disposed on
`or in the visible light transparent substrate 130. The visible
`light transparent substrate 130 includes a major surface 132
`and is electrically insulating. The visible light transparent
`substrate 130 can be formed of any useful electrically insu
`lating material Such as, e.g., glass or polymer. Examples of
`useful polymers for light transparent substrate 130 include
`polyethylene terephthalate (PET) and polyethylene naphtha
`late (PEN). The electrically conductive micropattern 140 can
`be formed of a plurality of linear metallic features.
`0058 FIG. 2 also illustrates an axis system for use in
`describing the conductive visible light transparent region 101
`that would lie within a touch sensing area of a touch screen
`panel. Generally, for display devices, the X and y axes corre
`spond to the width and length of the display and the Z axis is
`typically along the thickness (i.e., height) direction of a dis
`play. This convention will be used throughout, unless other
`wise stated. In the axis system of FIG. 2, the x axis and y axis
`are defined to be parallel to a major surface 132 of the visible
`light transparent substrate 130 and may correspond to width
`and length directions of a square or rectangular Surface. The
`Z axis is perpendicular to that major Surface and is typically
`along the thickness direction of the visible light transparent
`substrate 130. A width of the plurality of linear metallic
`features that form the electrically conductive micropattern
`
`140 correspond to an x-direction distance for the parallel
`linear metallic features that extend linearly along the y axis
`and a y-direction distance for the orthogonal linear metallic
`features correspond to a width of the orthogonal linear metal
`lic features. A thickness or height of the linear metallic fea
`tures corresponds to a Z-direction distance.
`0059. In some embodiments, the conductive visible light
`transparent region 101 that would lie within a touch sensing
`area of a touch screen panel includes two or more layers of
`visible light transparent substrate 130 each having a conduc
`tive micropattern 140.
`0060. The conductive micropattern 140 is deposited on the
`major surface 132. Because the sensor is to be interfaced with
`a display to form a touch screen display, or touch panel
`display, the substrate 130 is visible light transparent and sub
`stantially planar. The Substrate and the sensor may be Sub
`stantially planar and flexible. By visible light transparent,
`what is meant is that information (e.g., text, images, or fig
`ures) that is rendered by the display can be viewed through the
`touch sensor. The viewability and transparency can be
`achieved for touch sensors including conductors in the form
`of a deposited metal, even metal that is deposited with thick
`ness great enough to blocklight, if the metal is deposited in an
`appropriate micropattern.
`0061 The conductive micropattern 140 includes at least
`one visible light transparent conductive region overlaying a
`viewable portion of the display that renders information. By
`visible light transparent conductive, what is meant is that the
`portion of the display can be viewed through the region of
`conductive micropatternand that the region of micropatternis
`electrically conductive in the plane of the pattern, or stated
`differently, along the major surface of the substrate onto
`which the conductive micropattern is deposited and to which
`it is adjacent. Preferred conductive micropatterns include
`regions with two dimensional meshes, e.g. square grids, rect
`angular (non-square) grids, or regular hexagonal networks,
`where conductive traces define enclosed open areas within
`the mesh that are not deposited with conductor that is in
`