PATENT DOCUMENT

Publication Number: US-9787934-B2
Application Number: US-201414155741-A
Country: US
Kind Code: B2

Title: Wireless devices with touch sensors and solar cells

Abstract:
A wireless input-output device may gather touch input from a user. The touch input may be wirelessly transmitted to external wireless equipment such as a computer. The wireless device has a touch sensor and a solar cell that converts ambient light into electrical power. Wireless communications circuitry transmits the touch input to the external equipment using the electrical power from the solar cell. Energy storage devices such as a capacitor and a battery can be charged using the electrical power. The wireless device may have a transparent cover layer. The touch sensor may be a transparent touch sensor that is located between the cover layer and the solar cell or the solar cell may be a transparent solar cell that is located between the transparent cover layer and the touch sensor.

Claims:
What is claimed is: 
     
       1. A wireless electronic device that supplies user touch input to external wireless electronic equipment, comprising:
 a touch sensor that receives the user touch input from an external object; 
 a solar cell that converts ambient light into electrical power; 
 wireless communications circuitry that uses the electrical power from the solar cell to transmit the user touch input to the external wireless electronic equipment, wherein the touch sensor has a rectangular shape and wherein the solar cell is located within a rectangular ring-shaped border that surrounds the touch sensor; 
 a transparent cover layer that overlaps the touch sensor and the rectangular ring-shaped border; and 
 a layer of visible-light-blocking material that is coated on an underside of the transparent cover layer and that overlaps the touch sensor, wherein the solar cell wraps around the layer of visible-light-blocking material within the rectangular ring-shaped border. 
 
     
     
       2. The wireless electronic device defined in  claim 1  wherein the external wireless electronic equipment comprises a computer, wherein the wireless electronic device comprises a wireless track pad, and wherein the touch sensor comprises an array of capacitive touch sensor electrodes. 
     
     
       3. The wireless electronic device defined in  claim 1 , wherein the layer of visible-light-blocking material is unpatterned. 
     
     
       4. The wireless electronic device defined in  claim 1 , wherein the layer of visible-light-blocking material is a uniform film. 
     
     
       5. The wireless electronic device of  claim 1  further comprising a layer of adhesive between the touch sensor and the layer of visible-light-blocking material. 
     
     
       6. The wireless electronic device defined in  claim 1  wherein the touch sensor comprises transparent capacitive touch sensor electrodes. 
     
     
       7. The wireless electronic device defined in  claim 1  wherein the solar cell comprises a transparent solar cell. 
     
     
       8. The wireless electronic device defined in  claim 1  wherein the touch sensor comprises a transparent touch sensor. 
     
     
       9. The wireless electronic device defined in  claim 1  wherein the touch sensor comprises a transparent touch sensor and wherein the solar cell comprises a transparent solar cell.

Description:
BACKGROUND 
     This relates generally to wireless devices for controlling electronic devices such as computers, and, more particularly, to wireless input-output devices with touch sensors. 
     Computers and other electronic devices are often controlled using input-output devices such as keyboards, mice, and track pads. These devices are often provided with wireless circuitry that allows the devices to be operated without being connected to a host by cable. The ability to wirelessly communicate with external equipment allows wireless input-output devices to be freely moved around by a user without worrying about cable length restrictions, cable tangles, and other inconveniences associated with using wired input-output devices. 
     Unfortunately, wireless input-output device are not able to receive power through a permanent wired connection. This creates a need for an alternate source of power. Disposable and rechargeable batteries are possible power sources for wireless input-output devices, but can be inconvenient to use. Rechargeable batteries use battery charging equipment that may be misplaced or may otherwise be inaccessible when batteries become depleted. Disposable batteries that have become depleted must be removed from the wireless input-output device and replaced with fresh disposable batteries, but fresh disposable batteries are not always available. 
     It would therefore be desirable to be able to provide improved wireless electronic devices such as wireless input-output devices for controlling external electronic equipment. 
     SUMMARY 
     A wireless input-output device may gather touch input from a user. The touch input may be wirelessly transmitted to external wireless equipment such as a computer. The wireless device may be a track pad, a touch sensitive computer mouse, a keyboard with an integrated trace pad, or other wireless accessory. 
     The wireless device may have a touch sensor that gathers user touch input and a solar cell that converts ambient light into electrical power. Wireless communications circuitry in the wireless device may transmit the touch input to the external equipment. A power regulator may be used to supply the electrical power from the solar cell to the wireless communications circuitry and to the touch sensor. Energy storage devices such as a capacitor and a battery may be used to store electrical energy using the electrical power from the solar cell. 
     The wireless device may have a transparent cover layer. The touch sensor may be a transparent touch sensor that is located between the cover layer and the solar cell or the solar cell may be a transparent solar cell that is located between the transparent cover layer and the touch sensor. 
     The touch sensor may have a shape such as a rectangular shape that is surrounded by a border region. The solar cell may overlap a touch sensor with this type of configuration or may be located in the border region. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram of illustrative wireless input-output devices that are wirelessly communicating with external electronic equipment in accordance with an embodiment. 
         FIG. 2  is a schematic diagram of an illustrative system having equipment that is controlled using one or more associated wireless input-output devices in accordance with an embodiment. 
         FIG. 3  is a perspective view of an illustrative two-sided touch sensor for a wireless input-output device in accordance with an embodiment. 
         FIG. 4  is a top view of an illustrative pattern that may be used when implementing a one-sided touch sensor for a wireless input-output device in accordance with an embodiment. 
         FIG. 5  is a cross-sectional side view of an illustrative solar cell of the type that may be used in powering a wireless input-output device in accordance with an embodiment. 
         FIG. 6  is a cross-sectional side view of an illustrative wireless track pad of the type that may be powered using a solar cell in accordance with an embodiment. 
         FIG. 7  is a cross-sectional side view of an illustrative wireless touch-sensitive mouse of the type that may be powered using a solar cell in accordance with an embodiment. 
         FIG. 8  is a cross-sectional side view of an illustrative stack-up in a wireless input-output device that includes a touch sensor above a solar cell in accordance with an embodiment. 
         FIG. 9  is a graph showing an illustrative spectral response for a solar cell in accordance with an embodiment. 
         FIG. 10  is a graph of a transmission characteristic for an illustrative ink or other visible-light-blocking layer that may be used as a layer in a wireless input-output device in accordance with an embodiment. 
         FIG. 11  is a graph of a transmission characteristic for an illustrative ink or other visible-light-blocking layer with fluorescent light transmission bands in accordance with an embodiment. 
         FIG. 12  is a cross-sectional side view of illustrative layers in a wireless input-output device with a touch sensor and solar cell in which a visible-light-blocking layer such as a layer of ink hides the touch sensor and solar cell from view in accordance with an embodiment. 
         FIG. 13  is a cross-sectional side view of illustrative layers in a wireless input-output device with a touch sensor and solar cell in which a visible-light-blocking layer such as a layer of ink under a clear touch sensor is used to hide the solar cell in accordance with an embodiment. 
         FIG. 14  is a cross-sectional side view of illustrative layers in a wireless input-output device with a touch sensor and solar cell in which ink or a layer of other light-blocking material is located under a clear touch sensor and a clear solar cell in accordance with an embodiment. 
         FIG. 15  is a cross-sectional side view of illustrative layers in a wireless input-output device with a touch sensor and solar cell in which a light-blocking layer of material such as a layer of ink under a clear solar cell is used to hide a touch sensor in accordance with an embodiment. 
         FIG. 16  is a cross-sectional side view of illustrative layers in a wireless input-output device with a touch sensor and solar cell in which a clear touch sensor is located under a clear solar cell and in which a layer of light-blocking material such as a layer of ink is located under the clear touch sensor in accordance with an embodiment. 
         FIG. 17  is a cross-sectional side view of illustrative layers in a wireless input-output device with a touch sensor and solar cell in which an opaque touch sensor is located under a clear solar cell in accordance with an embodiment. 
         FIG. 18  is a cross-sectional side view of illustrative layers in a wireless input-output device with a touch sensor and solar cell formed from shared structures such as a patterned layer of material on a substrate in accordance with an embodiment. 
         FIG. 19  is a perspective view of an illustrative wireless input-output device such as a track pad in accordance with an embodiment. 
         FIG. 20  is a cross-sectional side view of illustrative layers in a wireless input-output device with a touch sensor that is surrounded by an inactive border region containing a solar cell such as the input-output device of  FIG. 19  in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Wireless input-output devices can be used to control electronic equipment such as set-top boxes, televisions, computers, portable electronic devices, or other host devices. An illustrative system environment in which wireless input-output devices are being used to control a host such as a computer or other external electronic equipment is shown in  FIG. 1 . As shown in  FIG. 1 , wireless input-output devices  10  may include wireless computer accessories such as wireless keyboard  10 A, wireless track pad  10 B, and wireless mouse  10 C. Wireless keyboard  10 A may have keys  12  and an integrated track pad such as track pad  14 . Wireless track pad  10 B may have a planar surface such as surface  16  that is used to gather touch input from a user. Portion  18  of wireless mouse  10 C may be used to gather touch input from a user. Devices  10 B and  10 C may also have buttons or other components to receive user input. 
     Wireless links  20  may be used to support communications between wireless input-output devices  10  and external wireless electronic equipment such as wireless host device  22 . Wireless links  20  may be low-energy Bluetooth® link, other short-range low power wireless links, or other wireless communications paths (e.g., wireless paths using radio-frequency transmissions associated with radio-frequency transceivers, ultrasonic sound transmissions, light transmissions, or other transmissions that do not require cabling between devices  10  and device  22 ). 
     Host device  22  may have a housing such as housing  26  in which display  24  is mounted or may be implemented without a display (e.g., in a set-top box configuration). Host  22  may be controlled using user input from input-output devices  10 . For example, a user may use one or more of devices  10  to gather user touch input that positions a cursor on device  22 , to gather multi-touch gesture input, to click on a desired on-screen option being presented to a user on display  24 , or may otherwise use devices  10  to supply user input to host  22 . The user input that is wirelessly transmitted to host  22  preferably includes user touch input gathered with a touch sensor in device  10 . Host  22  may optionally supply output to a user through wireless devices  10 . For example, host  22  may transmit information to devices  10  that devices  10  display using status-indicator lights or other output structures. 
     A schematic diagram of the equipment of  FIG. 1  is shown in  FIG. 2 . As shown in  FIG. 2 , wireless external electronic equipment such as host  22  may have wireless communications circuitry  42 . Electronic input-output device  10  may have wireless communications circuitry  40 . Wireless radio-frequency transceiver circuitry such as wireless communications circuitry  40  and  42  may be used to support communications over wireless link  20 . The communications may be unidirectional between device  10  and device  22  or may be bidirectional. 
     Device  10  may have touch sensor functionality and light-based power generation capabilities. For example, device  10  may have a touch sensor such as touch sensor  28  and light-based power circuitry  34 . Light-based power circuitry  34  may convert light that is incident on device  10  into electrical power for powering the circuitry of device  10 . Touch sensor  28  may be used for gathering user touch input from a user. 
     Touch sensor  28  may include touch sensor electrodes such as touch sensor electrodes  30 . Touch sensor electrodes  30  may be capacitive touch sensor electrodes for capacitive touch sensing. Touch sensor processing circuitry  32  may be used to supply drive signals to touch sensor electrodes  30  and to gather corresponding sense signals. Touch sensor processing circuitry  32  may process the signals associated with touch sensor electrodes  30  (e.g., drive signal and sense signal data) and may use this information to generate touch data. Touch sensor electrodes  30  may form an array across the surface of touch sensor  28 . Touch sensor processing circuitry  32  may use the array of touch sensor electrodes  30  to gather lateral (X-Y) position information on the point or points of contact of an external object or objects (e.g., a stylus, one or more user fingertips, etc.) with sensor  28 . Motion information representing how an external object moves across the surface of the touch sensor array may also be gathered by touch sensor  28 . User touch input that is gathered by touch sensor  28  may include information on where a user&#39;s finger or other external object clicks (presses down) on the touch sensor, location data (i.e., information on where the user&#39;s finger(s) or other external object touches the touch sensor), and touch gesture information (e.g., information on finger swipes, information on multitouch gestures such as pinch-to-zoom gestures, information on multi-finger swipe gestures, and other touch input involving the motion of one or more fingers or other external objects across the touch sensor). If desired, non-capacitive touch sensor technology may be used in touch sensor  28 . For example, touch sensor  28  may be implemented using acoustic touch technology, force-based touch sensor technology, resistive touch technology, etc. The use of a capacitive touch sensor for touch sensor  28  of device  10  in  FIG. 2  is merely illustrative. 
     Power circuitry  34  may include a light-based source of power such as solar cell  36 . Solar cell  36  (sometimes also referred to as a photovoltaic cell or light-based power source) may be based on inorganic semiconductors (e.g., crystalline silicon, polysilicon, amorphous silicon, cadmium telluride, gallium arsenide, etc.), organic semiconductors (e.g., polymers such as polyphenylene vinylene), or other suitable materials. During operation, solar cell  36  is exposed to ambient light and converts the ambient light to electrical power. The electrical power from solar cell  36  may be stored in one or more energy storage devices  44  such as a battery or capacitor. Power regulator  38  may be used in regulating the flow of power from solar cell  36  to energy storage circuitry  44  and in regulating the flow of power to the circuitry of device  10  from solar cell  36  and from energy storage devices  44 . For example, power regulator  38  may provide electrical power from solar cell  36  to storage device  44  and/or other components in device  10  such as touch sensor  28  and wireless communications circuitry and other circuitry  40  and may be used in providing electrical power from storage device  44  to circuitry such as touch sensor  28  and wireless communications circuitry and other circuitry  40 . 
     Wireless communications circuitry and other circuitry  40  in device  10  may be used to support wireless communications with external devices such as device  22  (e.g., by communicating with wireless communications circuitry  42  in device  22  over wireless link  20 ). Wireless communications circuitry  40  may, for example, transmit user touch input to external wireless equipment  22  using electrical power from solar cell  36  (i.e., electrical power provided to circuitry  40  using regulator  38 ). The wireless communications circuitry of device  10  and device  22  may include low-energy Bluetooth® transceiver circuitry and/or other short-range low power wireless circuitry (e.g., wireless local area network transceiver circuitry). Wireless communications circuitry  40  and  42  may also include cellular telephone circuitry or other longer range transceivers, if desired. In general, power consumption may be minimized by using low power wireless schemes such as by using wireless communications circuitry  40  that relies solely or primarily on short range low power transceiver circuits for communicating with a nearby host (i.e., for communicating with a computer that is within a 3 meters of device  10  or other suitable distance). 
     To control the operation of device  10 , circuitry  40  may include control circuitry. The control circuitry may include storage and processing circuitry. The storage and processing circuitry may include storage such as hard disk drive storage, nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory configured to form a solid state drive), volatile memory (e.g., static or dynamic random-access memory), etc. Processing circuitry in circuitry  40  may be used in controlling the operation of device  10 . The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors, power management units, audio codec chips, application specific integrated circuits, etc. 
     If desired, device  10  may include input-output devices in addition to touch sensor  28 . For example, circuitry  40  may include buttons, joysticks, click wheels, scrolling wheels, touch pads, key pads, keyboards, microphones, speakers, tone generators, vibrators, cameras, sensors, light-emitting diodes and other status indicators, data ports, displays, etc. A user can control the operation of device  10  by supplying commands through these input-output devices in addition to supplying touch input through an input-output device such as touch sensor  28  and may receive status information and other output from device  10  using the output resources of these input-output devices. The input-output resources of device  10  may, if desired, include one or more input-output connectors such as digital data connectors, analog signal connectors, connectors that handle power, analog signals, and/or digital data, or other input-output connectors. If desired, device cost and complexity can be minimized by omitting some or all of these additional input-output devices. 
     Touch sensors such as touch sensor  28  may use electrodes  30  in a capacitive touch sensor arrangement such as the illustrative configuration of  FIG. 3 . As shown in  FIG. 3 , electrodes  30  may be formed on a substrate such as substrate  50 . Substrate  50  may be a dielectric such as glass, ceramic, plastic, or other suitable material. If desired, substrate  50  may be shared with other structures in device  10  (e.g., solar cell structures, protective cover layer structures, housing structures, etc.). The configuration of  FIG. 3  is merely illustrative. 
     Capacitive touch sensor electrodes  30  may have square shapes, diamond shapes, or other shapes that allow sensor  28  to determine the location of external object  56  relative to sensor  28  in lateral dimensions X and Y. In the example of  FIG. 3 , electrodes  30  include elongated rectangular upper surface electrodes  52  that run along lateral dimension Y on the upper surface of substrate  50  and elongated rectangular lower surface electrodes  54  that run along lateral dimension X on the lower surface of substrate  50  (i.e., electrodes  52  may run perpendicular to electrodes  54 ). Paths  58  may be used to supply drive signals to electrodes  52  and to gather corresponding sense signals from electrodes  54  (as an example). During operation, an external object such as external object  56  (i.e., one or more fingers of a user or a stylus) may be placed in the vicinity of the surface of touch sensor  28  (e.g., directly on sensor  28  or within a few millimeters or other suitable distance of the surface of sensor  28 ). Touch sensor processing circuitry  32  ( FIG. 2 ) is used to determine the location of the touch event (i.e., the point of contact of object  56  in dimensions X and Y) based on signals from electrodes  30 . Lateral position data (i.e., position information in lateral dimensions X and Y) may be used to control the location of a pointer or other icon on a display associated with device  22  or may otherwise be used as input to device  22 . 
     If desired, touch sensor electrodes  30  may be formed on a single side of substrate  50 . A portion of an illustrative one-sided touch sensor array is shown in  FIG. 4 . As shown in  FIG. 4 , touch sensor  28  may contain diagonally interconnected square electrodes  30  on a surface of substrate  50  some of which are used to carry drive signals D and some of which are used to gather corresponding sense signals S. When a user&#39;s finger or other external object is placed in the vicinity of electrodes  30  (e.g., in the vicinity of a pair of electrodes), sensor circuitry  32  can gather signal data that is converted into user touch input to be conveyed wirelessly to device  22 . Electrodes  30  may be implemented using rectangular pads, narrow or thick lines of conductive material, diamond-shaped pads, meandering traces, or other suitable patterned conductor shapes. 
     Electrodes  30  for a two-sided touch sensor of the type shown in  FIG. 3  or for a one-sided touch sensor of the type shown in  FIG. 4  may be formed from conductive materials. In some arrangements, electrodes  30  may be formed from metals such as copper, aluminum, gold, etc. In other arrangements, electrodes  30  may be formed from transparent conductive material such as indium tin oxide or indium zinc oxide (e.g., a transparent semiconductor or other transparent conductive material). 
     Solar cell  36  is formed from semiconducting materials. A cross-sectional side view of solar cell  36  is shown in  FIG. 5 . As shown in  FIG. 5 , solar cell  36  may have multiple layers such as upper layer  36 A and lower layer  36 B. Additional layers (e.g., thin layers of metal, etc.) may also be included in solar cell  36 . In the example of  FIG. 5 , layer  36 A is a layer of p-type silicon and layer  36 B is a layer of n-type silicon. Other semiconductors (e.g., other inorganic semiconductors and/or organic semiconductors) may be used, if desired. The semiconductor material that is used in forming solar cell  36  (i.e., layers such as layers  35 A and  36 B) may be formed from materials that are opaque in the visible spectrum and/or materials that are transparent (clear) in the visible spectrum (or that are sufficiently thin to be effectively transparent in the visible spectrum). The materials used in forming solar cell  36  may be transparent or opaque at infrared wavelengths. 
     During operation of solar cell  36 , ambient light  62  (e.g., daylight and/or artificial light) is incident on solar cell  36  and produces an output voltage V across solar cells  60 . Output voltage V can be used to power touch sensor  28 , wireless circuitry  40 , and other components in device  10  and can be used to store energy in energy storage  44  ( FIG. 2 ). When ambient light levels are low, power can be provided by energy storage device  44  (e.g., instead of using solar power or to supplement power from solar cell  36 ). 
     A cross-sectional side view of an illustrative electronic device such as device  10 B of  FIG. 1  is shown in  FIG. 6 . Electronic device  10 B may be a track pad. As shown in the cross-sectional side view of  FIG. 6 , track pad  10 B may rest on a table or other support structure having support surface  74 . Main touch sensor structure  64  (e.g., a planar member that lies in the X-Y plane of  FIG. 6 ) may be supported using support legs such as legs  66  and  70 . Legs such as legs  66  may be tall rear legs that tilt surface  64  towards a user. Solar cell  36  and touch sensor  28  may be mounted within structure  64 . 
     Switch structures such as switch  68  or other force-sensitive components may be interposed within leg  70  or elsewhere in device  10 B to monitor when a user has used finger  56  to press downwards on surface  64  in direction  72  (i.e., parallel to vertical axis Z). A user may, for example, position fingers such as finger  56  in X and Y, while touch sensor  28  in main structure  64  is gathering X-Y position data and may press downwards in direction  72  on structure  64  when it is desired to click on an on-screen option or to otherwise provide a “click” input. Ambient light  62  that is incident on structure  64  is converted into power by solar cell  36  in structure  64 . 
     A cross-sectional side view of an illustrative electronic device such as device  10 C of  FIG. 1  is shown in  FIG. 7 . Electronic device  10 C may be a computer mouse. As shown in the cross-sectional side view of  FIG. 7 , mouse  10 C may rest on a table or other support structure having a surface such as support surface  74 . Optical sensor  76  or other sensors may be used to gather information on the lateral movement of mouse  10 C across surface  62  in the X-Y plane of  FIG. 7 . Touch sensor  28  may be mounted in a region such as region  78  along the upper surface of mouse  10 C. Touch sensor  28  in mouse  10 C may be used to gather location information for touch events (i.e., touch input associated with contact between external object  56  and the surface of device  10 C). A user may supply single-finger and multi-finger gestures to mouse  10 C using touch sensor  28 . Solar cell  36  may be mounted within device  10 C (e.g., in region  78 , in a border surrounding region  78 , or elsewhere) to generate power from ambient light  62 . If desired, mouse  10 C may include one or more buttons to receive click inputs in addition to or instead of gathering click (tap) inputs from touch sensor  28 . 
     In configurations of the type shown in  FIG. 6 , input-output device  10  (e.g., track pad  10 B) has a planar surface for gathering touch input with touch sensor  28 . In configurations of the type shown in  FIG. 7 , input-output device  10  (e.g., computer mouse  10 C) has a curved surface for gathering touch input with touch sensor  28 . In forming devices with curved surfaces such as illustrative device  10 C of  FIG. 7 , it may be desirable to form touch electrodes  30  and solar cell  36  using flexible substrates that can be bent to conform to the curved device surface or it may be desirable to form touch electrodes  30  and/or solar cell  36  by depositing layers of material (e.g., polysilicon for a solar cell and/or indium tin oxide or other materials for a touch sensor) onto a curved support structure, thereby forming touch sensor and solar cell structures with a curved shape. Arrangements using a combination of these approaches may also be used. For example, device  10  may be formed by bending touch and solar cell structures to accommodate attachment to a curved surface in device  10  and/or touch sensor and solar cell layers may be deposited on a curved substrate, thereby avoiding the need to bend separate touch and/or solar cell substrates into a desired shape. Configurations for device  10  that have flat surfaces are sometimes described as an example. These configurations are, however, merely illustrative. Device  10  may have a planar top surface, may have a curved top surface, or may have a housing that has planar and curved portions. 
     A cross-sectional side view of an illustrative configuration for the touch sensor and solar cell structures that may be used in forming device  10  is shown in  FIG. 8 . As shown in  FIG. 8 , device  10  may have a clear cover layer such as cover layer  80 . Cover layer  80  may be transparent so that ambient light  62  passes through cover layer  80 . Cover layer  80  may be formed from a transparent structure such as a layer of transparent glass, a clear plastic layer, or other transparent material. Adhesive  82  (e.g., clear adhesive) such as liquid adhesive or pressure sensitive adhesive may be used to attach touch sensor  28  to the underside of cover layer  80  and to attach solar cell  36  to the underside of touch sensor  28 . If desired, adhesive layers  82  may be omitted (e.g., in configurations in which the structures of cover layer  80 , touch sensor  28 , and solar cell  36  are formed by depositing layers of material on the underside of cover layer  80 , in configurations in which layers are laminated together using heat and pressure in the absence of intervening adhesive, or in other configurations). 
     In the configuration of  FIG. 8 , touch sensor  28  is interposed between cover layer  80  and solar cell  36 . Touch sensor  28  of  FIG. 8  may be formed using transparent material for electrodes  30  and transparent material for substrate  50  (i.e., touch sensor  28  of  FIG. 8  may be a transparent touch sensor). Transparent substrate  50  may be a layer of transparent plastic, a layer of transparent glass, or other clear material. Transparent electrodes  30  may be formed from clear conductive materials such as indium tin oxide or indium zinc oxide (as examples). As shown in  FIG. 8 , ambient light  62  passes through transparent touch sensor  28  and is absorbed by solar cell  36 . Solar cell  36  may be formed from an opaque solar cell structure such as a silicon-based solar cell structure (as an example). 
       FIG. 9  is a graph in which the spectral response of a silicon solar cell has been plotted. As shown in  FIG. 9 , when solar cell  36  is implemented using silicon, the response of the solar cell extends from blue visible light (with a wavelength about equal to 0.4 microns) to near infrared light (with a wavelength about equal to 1.1 microns). It may be desirable to block solar cell  36  from view by a user. To block solar cell  36  from view, a layer of material such as ink or plastic that is opaque to visible light may be interposed between the user and solar cell  36 . To allow solar cell  36  to receive sufficient ambient light  62  to produce electrical power, the visibly opaque material may be infrared-light transparent. For example, the visible-light-opaque material may be transparent at near infrared wavelengths above 0.7 microns (i.e., at the red end of the visible spectrum). By ensuring that the visible-light-opaque material is transparent in a suitable infrared wavelength range (e.g., 0.7 microns to 1.1 microns), a portion of ambient light  62  having infrared wavelengths (e.g., 0.7 microns to 1.1 microns) may be transmitted through the visible-light-blocking material to solar cell  36  to convert to electrical power. At the same time, the opacity of the visible-light-opaque material at visible wavelengths of 0.4 microns to 0.7 microns ensures that solar cell  36  will be blocked from view. If desired, the material that is used to hide solar cell  36  from view may have relatively narrow transmission windows at fluorescent light wavelengths (as shown in the graph of  FIG. 11 ), thereby allowing solar cell  36  to be powered by indoor light fixtures while still being significantly opaque to viewers at visible light wavelengths. 
       FIG. 12  is a cross-sectional side view of device  10  in an illustrative configuration in which visible-light-blocking material  90  (e.g., ink or other material with a transmission characteristic of the type shown in  FIG. 10  or  FIG. 11 ) is interposed between cover layer  80  and touch sensor  28 . Touch sensor  28  may be transparent so that light  62  (e.g., infrared light or fluorescent light that has passed through visible-light-blocking material  90 ) may reach solar cell  36 . Broadband visible light  62 ′ may be blocked by material  90 . Material  90  may be, as an example, a layer of black ink deposited on the lower surface of cover layer  80  that is transparent at near infrared wavelengths (or at narrow fluorescent light wavelengths). 
     In the illustrative configuration of  FIG. 13 , visible-light-blocking material  90  has been interposed between transparent touch sensor  28  and solar cell  36 . Visible-light blocking material  90  preferably blocks visible light  62 ′ while allowing ambient light  62  such as infrared light or fluorescent light to reach solar cell  36 . With the arrangement of  FIG. 12 , material  90  blocks both touch sensor  28  and solar cell  36  from view by a user. With the arrangement of  FIG. 13 , material  90  blocks solar cell  36  from view, while transparent touch sensor  28  is invisible or nearly invisible to the viewer due to the use of transparent electrodes  30  and transparent substrate  50 . 
       FIG. 14  is a cross-sectional side view of device  10  in an illustrative configuration in which both touch sensor  28  and solar cell  36  are transparent. A layer of material such as material  92  may be located below solar cell  36 . Material  92  may be ink or other material that is deposited on the lower surface of solar cell  36 , may be a separate structure formed from plastic, metal, or other material, or may be other structures visible through transparent touch sensor  28  and transparent solar cell  36 . As an example, material  92  may be black ink, white ink, silver ink, gold ink, red ink, ink of other colors, or other light-blocking material. Material  92  may be deposited in a uniform film (i.e., material  92  may be a blanket layer of unpatterned ink) or material  92  may be patterned (e.g., to form a logo that is visible through the layers of device  10 ). Material  92  may be opaque to visible light and, if desired, may be opaque to infrared light. 
     In the illustrative configuration of  FIG. 15 , solar cell  36  is interposed between touch sensor  28  and cover layer  80 . Because solar cell  36  lies above touch sensor  28 , it may be desirable to configure solar cell  36  to minimize electrical shielding effects, thereby allowing the capacitive electrodes of touch sensor  28  to gather touch data without being impeded by the presence of solar cell  36 . With one suitable arrangement, solar cell  36  is patterned so that the conductive layers of cell  36  have a pattern that minimizes interference with touch sensor  28  (e.g., solar cell  36  may be formed from a pattern with floating strips of solar cell material, each overlapping a respective elongated rectangular touch electrode such as electrodes  52  of  FIG. 3 , solar cell  36  may be formed from electrically floating squares of solar cell material, etc.). 
     Solar cell  36  of  FIG. 15  may be a transparent or opaque solar cell. If solar cell  36  is opaque, light  62  will be absorbed in solar cell  36 . The appearance of device  10  will therefore be determined by the appearance of solar cell  36 . In this type of situation, it may be desirable to form solar cell  36  from a blanket film of polysilicon or other semiconductor structures having a uniform appearance. 
     Touch sensor  28  of  FIG. 15  may be a transparent touch sensor or an opaque touch sensor. Material  92  may be interposed between solar cell  36  and touch sensor  28 . In arrangements in which solar cell  36  is transparent, the appearance of device  10  of  FIG. 15  will be controlled by the appearance of material  92 . For example, if material  92  is silver ink, device  10  will appear silver. 
       FIG. 16  shows how visible-light-blocking material  92  may be formed below touch sensor  28  in configurations in which both solar cell  36  and touch sensor  28  are transparent. Solar cell  36  is located above touch sensor  28 , so the intensity of light  62  reaching solar cell  36  is not diminished due to the presence of touch sensor  28 . Solar cell  36  and touch sensor  28  are clear, so the appearance of device  10  can be controlled by appropriate selection of the appearance of layer  92 . For example, if layer  92  is formed from silver ink, the silver color of the silver ink will be visible through transparent solar cell  36  and transparent touch sensor  28 . 
     If touch sensor  28  is opaque and has a satisfactory appearance, solar cell  36  may be transparent and may be interposed between touch sensor  28  and cover layer  80 , as shown in  FIG. 17 . With the arrangement of  FIG. 17 , the appearance of device  10  is determined by the appearance of touch sensor  28 , which is opaque (in this example). 
     If desired, solar cell structures for solar cell  36  such as semiconductor layers  36 A and  36 B of FIG. Sand touch sensor structures for touch sensor  28  such as electrodes  30  of  FIG. 4  may be formed from one or more shared layers of material.  FIG. 18  is a cross-sectional side view of device  10  in an illustrative configuration in which a layer of patterned material is formed on the bottom of a transparent substrate layer  102 . Layer  102 , which may be formed from clear glass, transparent plastic, or other transparent material, may be the outermost layer of device  10  (e.g., a layer such as cover layer  80 ) or may be covered with one or more other layers of structures. 
     As shown in  FIG. 18 , the patterned layer of material on the lower surface of substrate  102  may include sublayers such as layers  36 A and  36 B. Layers  36 A and  36 B may be p-type and n-type doped semiconductor layers that are layered on top of each other and connected to terminals  60  to serve as solar cell structures for solar cell  36 . The layer of material containing layers  36 A and  36 B is patterned to create gaps  100  (i.e., gaps filled with plastic, air, or other dielectric). Gaps  100  electrically isolate areas of the layer of material on the underside of layer  102 . These electrically isolated areas of material can have square shapes or other suitable shapes that allows the isolated areas to serve as touch sensor electrodes  30 . 
     The isolated areas of material (i.e., the square sections containing layers  36 A and  36 B) may be coupled to touch sensor signal lines  58  and may be diagonally interconnected to form drive lines D and sense lines S for touch sensor  28 , as shown in the illustrative electrode pattern of  FIG. 4 . Other electrode patterns may be used if desired (e.g., elongated rectangular patterns, etc.). Capacitors may be interposed in lines  58  to block direct-current (DC) solar cell signals and thereby prevent these DC signals from reaching touch sensor processing circuitry  32 , while allowing touch signals associated with touch sensor processing circuitry  32  to pass. 
     In the configuration of  FIG. 18 , shared solar cell and touch sensor electrode structures are patterned in a single layer on the bottom of substrate  102 . If desired, two-sided configurations may be used in which some structures (e.g., solar cell structures, touch sensor electrodes, or structures that serve both as touch sensor electrodes and solar cell structures) are formed on the upper surface of a substrate and in which other structures (e.g., solar cell structures, touch sensor electrodes, or structures that serve both as touch sensor electrodes and solar cell structures) are formed on an opposing lower surface of the substrate. Single-sided and two-sided substrates that incorporate shared touch sensor electrode and solar cell structures may also be formed in layers that are attached to one or more separate touch sensor layers and/or solar cell layers. 
     A solar cell can be formed in a border region of device  10 . A perspective view of an illustrative configuration for device  10  in which a rectangular touch sensor array (touch sensor  28 ) has been surrounded by a rectangular ring-shaped border (border  150 ) is shown in  FIG. 19 . One or more solar cells may be formed in border  120  in addition to or instead of forming solar cell  36  in the center of device  10  overlapping the rectangular touch sensor array. Border  120  may be devoid of touch sensor electrodes (i.e., border  150  may be insensitive to touch) or border  120  may contain touch sensor electrodes (i.e., touch sensor electrodes  30  may extend across the surface of device  10 ). In arrangements in which border  120  contains touch sensor electrodes, the touch sensor electrodes may be clear to permit light to reach underlying solar cell structures or solar cell  36  may be formed on top of the touch sensor electrodes. Illustrative stacking configurations for accommodating both touch sensor electrodes and solar cell  36  in border  120  are described in connection with  FIGS. 8-18 . 
       FIG. 20  is a cross-sectional side view of device  10  of  FIG. 19  taken along line  122  and viewed in direction  124  in a configuration in which border  120  is free of touch sensor electrodes  30  for touch sensor  28 . As shown in  FIG. 20 , touch sensor  28  may lie under central rectangular region  128  of substrate  126 . Region  128  may be free of solar cell structures (as shown in  FIG. 20 ) or may include solar cell structures. 
     Substrate  126  may be a layer of clear glass, transparent plastic, or other structure that allows light  62  to reach solar cell  36  in border  120  (e.g., a cover layer such as cover layer  80  or an internal substrate layer in device  10 ). In configurations in which central region  128  is free of solar cells structures, light-blocking layer  92  (e.g., a layer of black ink, silver ink, ink of other colors, or other opaque material) may be used to block touch sensor  28  from view. In region  120 , solar cell  36  may be uncovered by light-blocking structures or a layer of ink that blocks visible light while passing infrared light (or narrow fluorescent light wavelengths) can be used to cover solar cell  36  so that solar cell  36  receives light  62  while simultaneously blocking solar cell  36  from view. 
     The foregoing is merely illustrative and various modifications can be made by those skilled in the art without departing from the scope and spirit of the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20140115
Publication Date: 20171010
Grant Date: 20171010
Priority Date: 20140115
Inventors: LANG MATTHEW E.
Assignee: APPLE INC
CPC Classifications: [{"code": "H04N21/42224", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02S40/38", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y02E10/50", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04N5/63", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/26", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/044", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N2005/443", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/03543", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N5/4403", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/03547", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L31/02167", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10F77/311", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10F77/311", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y02E70/30", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04N5/63", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0446", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0445", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N21/42204", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N21/42204", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N5/63", "inventive": true, "first": true, "tree": "[]"}, {"code": "H02S40/38", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N21/42224", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y02E10/50", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/03543", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/03547", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y02E10/50", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/26", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04N21/42224", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/03547", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0445", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/03543", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/26", "inventive": true, "first": false, "tree": "[]"}, {"code": "H02S40/38", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 53521364