||||||||||||||||||||||||||||||||||||||llll||||||||||||||||||||||||||||||||||||||||||||||||
`
`US 20050030048A1
`
`(19; United States
`{12) Patent Application Publication (10) Pub. N0.: US 2005/0030048 A1
`Bolender et al.
`(43) Pub. Date: Feb. 10, 2005
`
`
`{54} CAI’ACITIVE SENSING DEVICE FOR USE
`IN A KEYI’AD ASSEMBLY
`
`Publication Classification
`
`{76}
`
`Inventors: Robert J. Bolender. Davis, (7A (US);
`Benjamin C. Rubensen. San Jose, (TA
`(US)
`
`(‘rirrespundcnce Address:
`WAGNER, MURABITO 81 HAO LLP
`Third Flour
`'Iwu North Market Street
`San Jose, CA 95113 (US)
`
`{21] Appl. N0.:
`
`101’635348
`
`(22
`
`Filed:
`
`Aug. 5, 2003
`
`Int. CL" ............................. GtilR 27726; G090 5:00
`{51)
`(52) U.S.Cl.
`............................................ 324166l;345.='174
`
`{57)
`
`ABS'I‘RAC'!‘
`
`One embodiment in accordance with the present invention
`includes a capacitive sensing device for use in a keypad
`assembly of an electronic system. The capacitive sensing
`device includes a substantially transparent single sheet
`capacitive sensor. The substantially transparent single sheet
`capacitive sensor is configured to be disposed within the
`keypad assembly without requiring the formation of key
`post holes therctlirough. Additionally,
`the substantially
`transparent single sheet capacitive sensor has a flexibility
`which enables desired tactile response during use of keys of
`the keypad assembly.
`
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`Page 1 of 24
`Page 1 of 24
`
`Wintek Exhibit 1012
`
`Wintek Exhibit 1012
`
`

`

`Patent Application Publication Feb. 10, 2005 Sheet 1 of 13
`
`US 2005/0030048 A1
`
`10
`
`
`
`Page 2 of 24
`Page 2 of 24
`
`

`

`Patent Application Publication Feb. 10, 2005 Sheet 2 of 13
`
`US 2005/0030048 A1
`
`201
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`
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`SENSOR 208
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`SWITCH
`SENS-OR
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`
`Page 3 of 24
`Page 3 of 24
`
`

`

`Patent Application Publication Feb. 10, 2005 Sheet 3 0f 13
`
`US 2005/0030048 A1
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`Page 4 of 24
`Page 4 of 24
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`

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`Patent Application Publication Feb. 10, 2005 Sheet 4 of 13
`
`US 2005/0030048 A1
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`Page 5 of 24
`Page 5 of 24
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`

`

`Patent Application Publication Feb. 10, 2005 Sheet 5 of 13
`
`US 2005/0030048 A1
`
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`Page 6 of 24
`Page 6 of 24
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`

`

`Patent Application Publication Feb. 10, 2005 Sheet 6 of 13
`
`US 2005/0030048 A1
`
`Substantially Transparent
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`Page 7 of 24
`Page 7 of 24
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`Page 8 of 24
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`

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`Patent Application Publication Feb. 10, 2005 Sheet 8 0f 13
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`US 2005/0030048 A1
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`Page 9 of 24
`Page 9 of 24
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`Patent Application Publication Feb. 10, 2005 Sheet 9 of 13
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`US 200510030048 A1
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`

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`Patent Application Publication Feb. 10, 2005 Sheet 10 0f 13
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`US 2005/0030048 A1
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`Page 11 of 24
`Page 11 of 24
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`

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`Patent Application Publication Feb. 10, 2005 Sheet 11 0f 13
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`US 2005/0030048 A1
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`Page 12 of 24
`Page 12 of 24
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`

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`Patent Application Publication Feb. 10, 2005 Sheet 12 0f 13
`
`US 2005/0030048 A1
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`Page 13 of 24
`Page 13 of 24
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`

`

`Patent Application Publication Feb. 10, 2005 Sheet 13 0f 13
`
`US 2005/0030048 A1
`
`Disposing a first pattern of
`conductive sensors above a
`
`Disposing a second pattern of
`conductive sensors above a
`
`
`
`
`
`substantially transparent substrate
`
`
`substantially transparent
`
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`
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`region and having at least a
`
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`portion thereof comprised of a
`
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`substantially transparent
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`material
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`1202
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`
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`1204
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`conductive bridges will be disposed
`1205
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`electrically couple portions of the second pattern of
`conductive sensors
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`Fig. 12
`
`Page 14 of 24
`Page 14 of 24
`
`

`

`US 2005/0030048 A1
`
`Feb. 10, 2005
`
`CAPACITIVE SENSING DEVICE FOR USE IN A
`KEYPAD ASSEMBLY
`
`BACKGROUND
`
`[0001] Currently there are at least two difi'ercnt techniques
`that a user of a mobile telephone can utilize in order to input
`text messages. The first technique is to utilize the numeric
`input buttons ot‘the mobile phone to input characters, which
`can be slow and tedious considering that some characters
`and techniques involve several key depressions per charac-
`ter. Asccond technique is for the mobile phone to be enabled
`with a capacitive sensor and character recognition abilities
`such that its user is able to gesture or “write” with his. or her
`linger over its buttons {without depressing the buttons) in
`order to input alphanumeric characters. This provides a
`quicker way for entering text into a mobile phone. Addi-
`tionally, gestures can also be used to navigate through the
`mobile phone operating system andior menus. However,
`there are disadvantages to the conventional techniques for
`fabricating the capacitive sensors associated with the finger
`gesture input.
`
`[0002] For example, a conventional technique is described
`in PCT publication WO 03100074 (the US. relative is
`published as US 2(Kl'3r’0025679)
`in which the capacitive
`sensor of a mobile phone includes holes to allow keypad
`posts to pass through in order to activate switches associated
`with depressed keys. One of the disadvantages of this
`conventional technique is that it involves a lot of compen-
`sation in the sensing circuitry of the capacitive sensor to
`accommodate the irregular sensor design associated with
`routing around the holes. As such, this type of capacitive
`sensor can require increased development eflort, time, and
`expense to adapt to diliferent electronic devices, since the
`compensation usually has to be customized for each hole
`layout, and reconfigured when the key post holes are rear-
`ranged.
`
`[0003] The present invention may address one or more of
`the above issues.
`
`SUMMARY
`
`[0004] One embodiment in accordance with the present
`invention includes a capacitive sensing device for use in a
`keypad assembly of an electronic system. The capacitive
`sensing device includes a substantially transparent single
`sheet capacitive sensor. The substantially transparent single
`sheet capacitive sensor is configured to be disposed within
`the keypad assembly without requiring the formation of key
`post holcs therethrough. Additionally,
`the substantially
`transparent single sheet capacitive sensor has a flexibility
`which enables desired tactile response during use of keys of
`the keypad assembly.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`is a diagram of an exemplary mobile
`1
`[0005] FIG.
`telephone that can be implemented to include one or more
`embodiments of the present invention.
`
`[0006] FIG. 2 is a diagram of an exemplary keypad
`assembly in accordance with an embodiment of the present
`invention.
`
`[0007] FIG. 3A is a diagram of an intermediate step in
`constructing an exemplary sensor that
`includes first and
`
`Page 15 of 24
`Page 15 of 24
`
`second sensor patterns in accordance with an embodiment of
`the present invention for a capacitive sensing device.
`
`[0008] FIG. BB is a diagram of an exemplary sensor
`pattern that includes conductive bridges in accordance with
`an embodiment of the present
`invention for a capacitive
`sensing device.
`
`[0009] FIG. 4 is a diagram of an exemplary capacitive
`sensing device that illustrates selective disposing of sub-
`stantially opaque conductive material in accordance with an
`embodiment of the present invention.
`
`[0010] FIG. 5 is a side section view of an exemplary
`capacitive sensing device in accordance with an embodi-
`ment of the present invention.
`
`[0011] FIG. 6 is a side section view of an exemplary
`capacitive sensing device in accordance with an embodi-
`ment of the present invention.
`
`[0012] FIG. 7A is a diagram of an intermediate step in
`constructing an exemplary sensor that
`includes lirst and
`second sensor patterns in accordance with an embodiment of
`the present invention for a capacitive sensing device.
`
`[0013] FIG. 7B is a diagram of is an exemplary sensor
`pattern that includes conductive bridges in accordance with
`an embodiment of the present invention for a capacitive
`sensing device.
`
`[0014] FIG. 8 is a diagram of an opaque conductive ink
`bridge in accordance with an embodiment of the present
`invention.
`
`[0015] FIG. 9 is a diagram ot‘ an exemplary capacitive
`sensing device that illustrates selective disposing of sub-
`stantially opaque conductive material in accordance with an
`embodiment of the present invention.
`
`[0016] FIG. 10 is a diagram illustrating the flexibility of
`a capacitive sensing device in accordance with an embodi-
`ment of the present invention.
`
`[0017] FIG. 11 is a side sectional view of a keyrnat that
`includes a capacitive sensing device in accordance with an
`embodiment of the present invention.
`
`[0018] FIG. 12 is a flowchart of operations performed in
`accordance with an embodiment of the present invention for
`fabricating a capacitive sensing device.
`
`[0019] The drawings referred to in this description should
`not be understood as being drawn to scale.
`
`DESCRIPTION OF PREFERRED
`EMBODIMENTS
`
`[0020] Reference will now be made in detail to embodi-
`ments of the invention, examples of which are illustrated in
`the accompanying drawings. While the invention will be
`described in conjunction with embodiments, it will be under~
`stood that they are not intended to limit the invention to
`these embodiments. 0n the contrary,
`the invention is
`intended to cover alternatives. modifications and equiva-
`lean, which may be included within the spirit and scope of
`the invention as defined by the appended claims. Further«
`more, in the following detailed description of the present
`invention, numerous specific details are set forth in order to
`provide a thorough understanding of the present invention.
`However, it will be obvious to one of ordinary skill in the art
`
`

`

`US 2005/0030048 A1
`
`Feb. 10, 2005
`
`that the present invention may be practiced without these
`specific details. In other instances, well known methods,
`procedures, components,
`and circuits have not been
`described in detail as not to unnecessarily obscure aspects of
`the present invention.
`
`is a diagram of an exemplary mobile
`1
`[0021] FIG.
`telephone 100 that can be implemented to include one or
`more embodiments in accordance with the present inven-
`tion. Specifically, a capacitive sensor l[riot shown) can be
`integrally disposed within a keypad region 106 of mobile
`phone 100 thereby enabling both conventional use of keys
`108 of the keypad region 106 having tactile “clicking”
`feedback while also enabling the capture of pointing and
`gesturing input when a user slides his or her finger over the
`surface of the keypad region 106 with or without actually
`depressing the keys 108. For example. if a user moved his
`or her finger over keypad region 106 to form the letter “".b
`the capacitive sensor would detect
`this motion and its
`character recognition circuitry would identify the motion
`and subsequently the letter “b” can be presented on a display
`104 of mobile phone 100. in this manner, a user of mobile
`phone 100 can enter alphanumeric text (or commands or
`other inputs) more easily with his or her linger via the
`capacitive sensing device than by utilizing keys 108 of
`keypad 106.
`
`It is noted that, keys 108 of mobile phone 100 can
`[0022]
`be lighted from behind. As such, the capacitive sensor can be
`implemented such that
`it
`is substantially transparent
`in
`regions beneath the keys 108 in order to allow the light to
`pass from behind the capacitive sensor to light the tops of
`keys 108. In this manner, the lighting of the keys 108 is not
`significantly adversely affected by the inclusion of the
`capacitive sensing device that is part 01" keypad 106.
`
`[0023] FIG. 2 is a diagram of an exemplary keypad
`assembly 200 in accordance with an embodiment of the
`present
`invention. Specifically, keypad assembly 200
`includes a capacitive sensor 208 that can he a thin and
`flexible sensor that utilizes substantially transparent com-
`ponents. Within one embodiment, capacitive sensor 208 can
`include a single sheet capacitive sensor that includes a single
`layer of substantially transparent conductive material, e.g.,
`indium tin oxide (ITO), and an extra layer of substantially
`opaque conductive material (e.g., silver ink, carbon ink, a
`mixture of silver and carbon inks, etc.) that protects the
`substantially transparent conductive material against crack-
`ing during manufacture andfor repetitive use. Since the
`substantially opaque conductive material application is also
`a redundant electrical path, it can be selectively disposed
`where desired. For example, the substantially opaque con-
`ductive material could be masked around certain features in
`
`the sensing region of the capacitive sensor 208 to allow
`illumination to pass directly through capacitive sensor 208.
`thereby allowing keys 204 of keypad structure 206 to be
`illuminated to enable visibility of keys 204 in low light. The
`single sheet capacitive sensor 208 can also include a sub"
`stantially transparent substrate, or the various patterns of the
`single sheet captive sensor 208 can be disposed on an
`existing component ol‘ the keypad assembly 200.
`
`[0024] The keypad assembly 200 for an electronic device
`(e.g., 100) includes keypad structure 206, a keymat 210 that
`is deformable to actuate switch sensors 214 via key posts
`212, and capacitive sensor 208 that is coupled to the keymat
`
`Page 16 of 24
`Page 16 of 24
`
`210 and the keypad structure 206. In this manner, when a
`user finger 202 exerts a downward force on one ofkeys 204,
`that key 204 is depressed (as shown} which in turn causes
`the deformation of capacitive sensor 208 along with keymat
`210 which results in the corresponding key post 212 actu-
`ating one or more switch sensors 214.
`It
`is noted that
`capacitive sensor 208 is not disposed beneath the keymat
`210 such that keypad post holes do not have to be formed
`within capacitive sensor 208, since such holes would com-
`plicate the sensing circuit (not shown) utilized to interpret
`signals received from capacitive sensor 208.
`
`In one embodiment, capacitive sensing device 208
`[0025]
`can be bonded to the top of the keymat 210 and the keypad
`stntcture 206 can be bonded to capacitive sensing device
`208. It is noted that keypad structure 206 could be many
`separate discrete keys that can be disposed on capacitive
`sensing device 208 or disposed on some intermediate mem-
`ber (or component) that is disposed on capacitive sensing
`device 208.
`
`[0026] Within FIG. 2, capacitive sensor 208 can be inte-
`grated into the keymat 210 which in one embodiment can be
`implemented with some type of rubber material. The keys
`204 of keypad structure 206 can be rigid plastic buttons
`which include both clear and opaque regions (c.g., painted
`on the outside with holes in the paint) to let any back lighting
`through for illumination. It is noted that the indicia of keys
`204 can look darkened when there's no light behind them
`and they can also glow when the back lighting is activated
`such as in response to a user activating one of buttons 204
`or a status change of the electronic device (e.g., 100). It is
`pointed out that capacitive sensor 208 can be flexible and
`thin enough such that it does not inhibit the tactile response
`associated with buttons 204. Instead, capacitive sensor 208
`enables the desired tactile response of the keys 204 which
`may include a responsive click or snap or less resistant
`responses. It is noted that the keypad assembly 200 is one
`integral unit.
`
`It is understood that capacitive sensor 208 includes
`[0027]
`a sensing region which can include where the buttons 204
`are located on a electronic device or system {e.g., keypad
`region 106). However,
`the sensing region of capacitive
`sensor 208 may be any shape, may be smaller than keypad
`region 106, andior may extend outside of where the buttons
`204 are into areas that can be covered up by the housing of
`the electronic device (eg, 100).
`
`It is noted that a single sheet capacitive sensor can
`[0028]
`include a single substrate that has two or more conductive
`sensing patterns disposed thereon in a common layer that
`can be utilized for, but not limited to, 2-dimensional capaci-
`tive sensing.
`
`[0029] FIG. 3A is a diagram ol‘ an intermediate step in
`constructing an exemplary capacitive sensor 300/\
`that
`includes a first capacitive sensor pattern 302 and a second
`capacitive sensor pattern 304 in accordance with an embodi-
`ment of the present
`invention for a capacitive sensing
`device. For example, capacitive sensor pattern 302 includes
`electrically coupled horizontal capacitive sensor
`traces
`while capacitive sensor pattern 304 includes the as yet
`electrically uncoupled vertical sensor traces.
`
`It is noted that capacitive sensor patterns 302 and
`[0030]
`304 each includes a layer of substantially transparent con-
`
`

`

`US 2005/0030048 A1
`
`Feb. 10, 2005
`
`ductive material {not shown) along with a layer of substan-
`tially opaque conductive material (shown). There are a wide
`variety of ways in accordance with the present embodiment
`to fabricate capacitive sensor patterns 302 and 304. For
`example, in one embodiment a sputtering process can be
`used to coat one side of a substantially transparent flexible
`substrate 301 with a layer of substantially transparent con-
`ductive material (eg, ITO}. The substantially transparent
`conductive material can then be selectively etched away
`from the surface of the substantially transparent flexible
`substrate 301, revealing an intended "diamond” patterns 302
`and 304 which can be used for a capacitive sensing process.
`Alternatively, the substantially transparent material can be
`applied in any manner to create the intended diamond
`patterns 302 and 304. It is noted that patterns 302 and 304
`may include any shapes and are not limited to the “diamond"
`patterns or the horizontal and vertical layout shown. After
`the etching prOcess ol‘ the substantially transparent conduc-
`tive material, a first layer of substantially opaque conductive
`material is deposited on top of the substantially transparent
`conductive material in the desired areas, Within capacitive
`sensor 300A, the substantially transparent conductive mate-
`rial and the substantially opaque conductive material are
`shown having a substantial one-to-one correspondence and
`alignment which is why the substantially transparent con-
`ductive material is not shown.
`
`in various embodi-
`is noted that
`[0031] Furthermore, it
`ments of the present invention, the first and second conduc-
`tive sensor patterns are comprised of the same type of
`substantially transparent conductive material. It is further
`noted that in various embodiments of the present invention,
`the first and second conductive sensor patterns are com—
`prised of different types of substantially transparent conduc—
`tive materials. Additionally,
`it
`is noted that
`in various
`embodiments of the present invention, the first and second
`conductive sensor patterns are comprised of the same type of
`substantially opaque conductive material. It is further noted
`that
`in various embodiments of the present invention, the
`first and second conductive sensor patterns are comprised of
`dilfcrcnt types of substantially opaque conductive materials.
`
`[0032] Within FIG. 3A, capacitive sensor pattern 302
`includes diamond shapes 318, 320, 322, 324, 326 and 328
`which can be disposed on a substantially transparent flexible
`substrate 301 as described herein. The diamonds shapes 318,
`320 and 322 of sensor pattern 302 have been disposed such
`that they are each electrically coupled together while dia-
`monds shapes 324, 326 and 328 have been disposed such
`that they are each electrically coupled together. As such, the
`components of capacitive sensor pattern 302 could be uti-
`lized if coupled to capacitive sensing circuitry {not shown).
`
`pattern 304
`sensor
`capacitive
`[0033] Alternatively,
`includes isolated diamond shapes 306, 308, 310. 312, 314
`and 316 which can be disposed on the substantially trans-
`parent flexible substrate 301 as described herein. The dia-
`mond shapes 306, 308, 310, 312, 314 and 316 are electri-
`cally isolated and are therefore not yet useful as input to
`capacitive sensing circuitry. However, it is pointed out that
`the substantially transparent conductive material of the
`diamond shapes of capacitive sensor patterns 302 and 304
`exist with a single layer which is advantageous for fabri-
`cating a capacitive sensing device that is thin and flexible.
`
`[0034] Within FIG. 3A, it is noted that the substantially
`transparent flexible substrate 301 of the present embodiment
`
`Page 17 of 24
`Page 17 of 24
`
`maybe implemented in a wide variety ot‘ways. For example,
`the substantially transparent flexible substrate 301 can be
`implemented with, but
`is not
`limited to. Polyethylene
`'l'erephthalate (PET). Additionally, the substantially trans-
`parent flexible substrate 301 can have a diverse range ot‘
`thickness which provide a desired amount of flexibility. For
`example, the substantially transparent flexible substrate 301
`can have a thickness of, but is not limited to, roughly 0.07
`millimeters (mm). It
`is noted that substrate 301 may be
`implemented such that one or more portions of it are not
`substantially transparent (cg, opaque markings, and the
`like). Additionally,
`the layer of substantially transparent
`conductive material of both capacitive sensor patterns 302
`and 304 can be implemented with diverse materials such as,
`but not
`limited to,
`indium tin oxide (ITO) or any other
`substantially transparent conductive material. Moreover, the
`layer of substantially opaque conductive material can be
`implemented in a wide variety of ways in accordance with
`the present embodiment. For example,
`the substantially
`opaque conductive material can be implemented as, but not
`limited to. conductive ink (cg, silver ink, carbon ink,
`mixture of silver and carbon inks, and the like}.
`
`[0035] FIG. 3|} is a diagram oi‘ an exemplary capacitive
`sensor 30013 that includes conductive bridges in accordance
`with an embodiment of the present invention for a capacitive
`sensing device. Specifically, capacitive sensor 300B illus—
`trates one embodiment of electrically coupling isolated
`diamonds 306, 308, 310, 312, 314 and 316 of capacitive
`sensor pattern 304 during a fabrication process of a capaci-
`tive sensing device.
`
`[0036] After the operation associated with FIG. 3A have
`occurred as described herein, an insulator 350 can then be
`disposed in areas where conductive bridges (c.g., 352 and
`354) of sensor pattern 304 will cross the sensor traces of
`sensor pattern 302 to facilitate electrically coupling of
`diamonds 306, 308, 310, 312, 314 and 316. For example,
`insulator 350 can be disposed between diamonds 310 and
`308 of sensor pattern 304 and also between diamonds 308
`and 306. Furthermore,
`insulator 350 can be disposed
`between diamonds 312 and 314 of sensor pattern 304 and
`also between diamonds 316 and 314.
`
`[0037] Within FIG. 33, a substantially opaque conductive
`material is next disposed to create conductive bridges (cg,
`352 and 354) that electrically couple diamonds 306, 308,
`and 310 together and diamonds 312, 314 and 316 together
`of sensor pattern 304 and does not electrically couple to
`sensor pattern 302. Specifically,
`the substantially opaque
`conductive material is disposed to create a conductive bridge
`352 which electrically couples diamonds 306 with 308 of
`sensor pattern 304. Additionally,
`the substantially opaque
`conductive material is disposed to create a conductive bridge
`354 which electrically couples diamonds 314 with 316. It is
`appreciated that diamonds 308 with 310 are also electrically
`coupled by a conductive bridge similar to bridge 354 while
`diamonds 314 with 312 are electrically coupled by a con-
`ductive bridge similar to bridge 352. In this manner, dia-
`monds 306, 308 and 310 of sensor pattern 304 are electri-
`cally coupled while diamonds 312, 314 and 316 are
`electrically coupled.
`
`a single layer of substantially
`In this manner,
`[0038]
`transparent Conductive material can be utilized in order to
`fabricate a two-dimensional capacitive sensing device. It is
`
`

`

`US 2005/0030048 A1
`
`Feb. 10, 2005
`
`noted that by including the layer of substantially opaque
`conductive material over the substantially transparent con-
`ductive material,
`the substantially transparent conductive
`material is protected from damage during manufacture and;r
`or repetitive use of the capacitive sensing device. Addition-
`ally. the substantially opaque conductive material can also
`provide electrical redundancy for the substantially transpar-
`ent conductive material if the substantially transparent con-
`ductive material fails. Therefore, a more reliable and thinner
`capacitive sensor device can be fabricated.
`
`It is noted that a substantially transparent insulator
`[0039]
`can be disposed over capacitive sensor 300B in order to
`provide a layer of protection for capacitive sensor patterns
`302 and 304 along with the conductive bridges (e.g., 352 and
`354).
`
`[0040] Within FIG. 3B, insulator 350 can be implemented
`in a wide variety of ways in accordance with the present
`embodiment. For example,
`insulator 350 can be imple-
`mented as, but is not limited to, a substantially transparent
`material, a substantially opaque material, an opaque mate-
`rial, andi’or a printed dielectric material. Additionally, the
`substantially opaque conductive material utilized to create
`the conductive bridges (cg, 352 and 354) can be imple—
`mented in diverse ways in accordance with the present
`embodiment. For example, the substantially opaque conduc-
`tive material can be implemented as, but not limited to,
`conductive ink (cg, silver ink, carbon ink, mixture ofsilver
`and carbon inks. and the like). It is noted that conductive
`bridges (e.g., 352 and 354) can be implemented in diverse
`ways in accordance with the present embodiment. For
`example, conductive bridges {e.g., 352 and 354) can be
`implemented as, but is not limited to, a substantially trans-
`parent conductive malerial, a substantially opaque conduc-
`tive material, audior an opaque conductive material.
`
`It is understood that the substantially opaque con-
`[0041]
`ductive material, substantially transparent conductive mate-
`rial, conductive bridges, andior insulators described herein
`can be disposed by utilizing, but not limited to, one or more
`deposition processes such as a screen printing process, one
`or more Iithographical processes such as an etching process,
`a combination of deposition and lithographical processes,
`and the like.
`
`[0042] FIG. 4 is a diagram of an exemplary capacitive
`sensing device 400 that
`illustrates selective disposing of
`substantially opaque conductive material in accordance with
`an embodiment of the present invention. It
`is noted that
`capacitive sensing device 400 can be fabricated in a manner
`similar to capacitive sensor patterns 300A and 300B of
`FIGS. 3A and SB, respectively, as described herein. The
`solid lines of capacitive sensing device 400 represent the
`substantially opaque conductive material while the dashed
`lines represent the underlying substantially transparent con—
`ductive material within an “illumination” opening 402 of
`capacitive sensing device 400. In this manner, light is able
`to pass through opening 402 of capacitive sensing device
`400 in order to illuminate one or more keys (cg, 204) of a
`keypad (eg, 206) associated with an electronic device (e.g.,
`100) while still providing capacitive sensing capabilities
`within opening 402 via the existing substantially transparent
`conductive material. It is understood that the underlying
`substantially
`transparent
`conductive material
`extends
`beneath the substantially opaque conductive material.
`
`Page 18 of 24
`Page 18 of 24
`
`[0043] Within capacitive sensing device 400, the substan-
`tially opaque conductive material of shapes 308a, 320a,
`314a and 3269 have been selectively disposed in order to
`create opening 402. Additionally, substantially opaque cort-
`ductive material shape 3240 has been selectively disposed
`such that it minimizes capacitive interference to conductive
`bridge 3520.
`In this manner, one or more patterns of
`substantially opaque conductive material can be tailored in
`order to minimize capacitive interference with one or more
`conductive bridges (e.g., 352a andror 354). It should be
`understood [or purpose of the present application the term
`“minimize capacitive interference" is intended to refer to
`disposing the conductive bridges in an orientation and
`location for reducing capacitive coupling between the con-
`ductive bridges and one or more proximate conductive
`sensor patterns.
`
`[0044] Within FIG. 4, it is noted that the capacitive sensor
`patterns 302a and 304aI of capacitive sensing device 400
`operate in manner similar to capacitive sensor patterns 302
`and 304 of FIGS. 3A and SB, described herein.
`
`[0045] FIG. 5 is a side section view of an exemplary
`capacitive sensing device 500 wherein a substantially
`opaque conductive material 504 is electrically coupled to at
`least a second portion of a substantially transparent conduc-
`tive material 502 within a capacitive sensor pattern that
`includes conductive sensors in accordance with an embodi-
`
`ment of the present invention. Specifically, it is pointed out
`that within capacitive sensing device 500. the substantially
`opaque conductive material 504 and the substantially trans-
`parent material 502 are substantially within the same layer
`as they both are disposed above a substantially transparent
`Substrate 506. In this manner, the combination of the sub-
`stantially transparent material 502 and the substantially
`opaque conductive material 504 are able to create one or
`more capacitive sensor traces of a capacitive sensor pattern
`that operates in manner similar to capacitive sensor patterns
`208, 300A, 300B andtor 400.
`
`It is noted that a finger (cg, 202) of a user could
`[0046]
`be on either side of capacitive sensing device 500 when it is
`in used. As such, capacitive sensing device 500 could be
`oriented such that substrate 506 is located above substan-
`
`tially transparent conductive material 502 and substantially
`opaque conductive material 504 or vice-versa. Hence,
`it is
`understood that when it
`is mentioned that something is
`"above” something else, it is typically in reference to the
`orientation of the Figures.
`
`It is noted that a capacitive sensor device (cg, 500)
`[0047]
`that operates in a manner similar to capacitive sensor device
`400 can be fabricated such that the light openings (e.g., 402)
`are created with substantially transparent conductive mate-
`rial 502 while the remainder of capacitive sensor device 500
`is created with substantially opaque conductive material
`504. In this fashion,
`the substantially opaque conductive
`material 504 would not be located above the substantially
`transparent conductive material 502, but instead would be
`situated within substantially the same layer or plane as
`illustrated within capacitive sensor device 500 of FIG. 5. In
`this manner,
`the substantially opaque conductive material
`504 and the substantially transparent conductive material
`502 would substantially abut each other.
`
`[0048] Within FIG. 5, it is noted that the substantially
`transparent flexible substrate 506 of the present embodiment
`
`

`

`US 2005/0030048 A1
`
`Feb. 10, 2005
`
`may be implemented in a wide variety ol’ways. For example,
`the substantially transparent flexible substrate 506 can be
`implemented with, but is not limited to, PET. Additionally,
`the substantially transparent flexible substrate 506 can have
`a diverse range of thickness which provide a desired amount
`of flexibility. For example,
`the substantially transparent
`flexible substrate 506 can have a thickness of, but is not
`limited to, roughly 0.07 mm. Additionally, the substantially
`transparent conductive material 502 can be implemented in
`diverse ways such as, but not limited to, ITO or any other
`substantially transparent conductive material. I'-‘urthem10re,
`the substantially opaque conductive material 504 can be
`implemented in a wide variety of ways in accordance with
`the