Patent Description:
<CIT> describes a woven article comprising a plurality of electrically insulating and/or electrically conductive yarn in the warp and a plurality of electrically insulating and/or electrically conductive yarn in the weft interwoven with the yarn in the warp. A functional yarn in the warp and/or the weft comprises an elongate substrate including at least one electrical conductor and at least one electronic device thereon, wherein the at least one electrical conductor provides directly and/or indirectly an electrical contact for connecting to the electronic device.

<CIT> describes a filamentous structure having textile character and comprising electronic components integrated into it. Said structure has an electronic filament part which substantially consists of the electronic components, flex wires electrically contacting the same and possible additional elements for mechanically stabilizing the structure. A textile filament part is wound around the electronic filament part and substantially consists of at least one textile filament.

<CIT> describes a light-emitting yarn thread texture comprising at least an LED package and more than two electrically-conductive strand wires, the conductive cores of the at least two electrically-conductive strand wires are electrically connected to at least two electrodes of the LED package, and each electrically-conductive strand wire is insulated with each other mutually. The exterior of the electrically-conductive strand wires and the LED package is woven and wrapped by insulation yarn threads. Also, the insulation yarn threads have quite thick texture at least at the position of connecting the LED package and the electrically-conductive strand wires.

<CIT> describes a light-emitting fabric prepared by attaching light-emitting diodes on a fabric having a flexibility almost the same as that of a common fabric. One or two or more of small type light-emitting diodes are integrally attached to the fibers constituting the fabric. For example, electrically conductive fiber or electrically conductive yarn are used as a part of the fiber constituting the fabric and small type light-emitting diodes are connected to them electrically directly, or no electrically conductive fiber or electrically conductive yarn is used but a small type light-emitting diode having wireless communication function is attached to the fibers constituting the fabric.

Examples are disclosed herein that relate to electronically functional yarns. The electronically functional yarn comprising a core, a sheath at least partially surrounding the core, wherein the sheath comprises one or more electronically non-functional windings, and an electronic circuit formed on the core. The circuit includes three or more control lines and more than three diode-containing circuit elements controllable by the three or more control lines, each circuit element being controllable via a corresponding set of two of the three or more control lines.

One or more of the circuit elements may comprise an input device in electrical series with a diode. The input device may comprise one or more of an infrared light sensor, a visible light sensor, an acoustic sensor, a pressure sensor, an antenna, a chemical sensor, and a haptic actuation device. One or more of the circuit elements alternatively or additionally may comprise an output device. In such an example, the output device may comprise one or both of a light-emitting diode and a haptic feedback device. In such an example, the output device may be in electrical series with a diode. The electronically functional yarn may be incorporated into a textile comprising a plurality of electronically non-functional yarns. In such an example, the electronically functional yarn may be one of a plurality of electronically functional yarns that form an array of diode-containing circuit elements incorporated in the textile. The electronically functional yarn alternatively or additionally may comprise a controller operatively coupled to the electronic circuit. In such an example, the controller may be configured to sequentially read input from one or more of the circuit elements. The sheath may comprise a thermoconductive material and may be configured as a heat exchanger. In another example, the sheath alternatively or additionally may comprise a conductive material and may be configured as an electrostatic discharge shield. The sheath alternatively or additionally may comprise one or more apertures each arranged at a location corresponding to a location of a respective circuit element. The sheath alternatively or additionally may comprise an electrically insulating yarn wound around the electronically functional core.

Electronic components may be incorporated into a textile article to form an electronically functional textile article. An electronically functional textile article may include any suitable electronic circuit elements. Examples include input devices (e.g. an optical sensor, a capacitive sensor, a resistive sensor, an acoustic sensor, a pressure sensor, a temperature sensor, a chemical sensor (e.g., for sensing gases such as NOx, CO<NUM>, and/or O<NUM>), or a haptic actuation device (e.g. a button, switch, and/or other physical interface)), output devices (e.g. light-emitting diodes (LEDs), haptic feedback devices (e.g. a vibro-motor or other actuator), and also other circuitry, such as an antenna for transmitting and/or receiving data, control circuitry such as a memory component and processing component (e.g., a microprocessor configured to execute applications), and power supply circuitry (e.g. one or more batteries, one or more solar cells, etc.).

<FIG> show aspects of an electronically functional clothing article <NUM> formed at least partially from an electronically functional textile <NUM>. Although article <NUM> takes the form of a shirt, this disclosure applies equally to other electronically functional textile articles and devices, such as soft-touch computing devices comprising textile exterior surfaces, wearable computing devices (e.g. head-mounted displays, functional gloves (e.g. a glove configured as a control device and/or output device for a computing system), wrist-worn devices, upholstery for furnishings, wall hangings, signage and other information displays, and internet of things (IOT) devices.

In this example, clothing article <NUM> comprises a plurality of LEDs that form a display <NUM>. In the state represented in <FIG>, display <NUM> outputs graphical content in the form of text. In the state represented in <FIG>, display <NUM> outputs graphical content in the form of a current time ("<NUM>:<NUM>"). <FIG> represents a state in which the display <NUM> is not outputting any displayed content. In this state, the plurality of LEDs - and thus the overall display <NUM> - may be relatively imperceptible.

As another example, <FIG> shows an example electronically functional glove <NUM>. Glove <NUM> may comprise various sensors, user input devices, and/or output devices incorporated directly into the textile of the glove via one or more electronically functional yarn segments. As examples, <FIG> shows an array <NUM> of LEDs arranged on glove <NUM>, and a plurality of motion sensors <NUM> arranged over the knuckle regions of the glove. It will be understood that these components are described as examples, and that any suitable electronic components may be used in an electronically functional glove or other electronically functional article.

An electronically functional yarn may be incorporated into an electronically functional textile in any suitable manner, such as by knitting, weaving or embroidery. <FIG> shows an example weave structure of textile <NUM>. In the depicted example, textile <NUM> includes a series of mutually parallel warp yarns <NUM>, and a series of mutually parallel weft yarns <NUM> running transverse to the warp yarns. Either or both series may include electronically functional yarns distributed among electronically non-functional yarns. As examples, <FIG> shows non-functional warp yarns <NUM> and non-functional weft yarn 304A integrated with electronically functional weft yarns 304B and 304C. <FIG> also illustrates electronic components <NUM> in electronically functional yarns 304B and 304C. Each component <NUM> may represent any suitable electronic component, including those described above. It will be noted that the sizes, locations, and general arrangement of components <NUM> are presented for example, and that any suitable arrangement of electronic component(s) on an electronically functional yarn may be used.

As yarns used to form textiles may be relatively narrow, it may be challenging to incorporate multiple individually-controllable electronic components into a yarn segment due at least in part to a number of control lines used to control the multiple components. Thus, as described in more detail below, the disclosed examples comprise diode-containing circuit elements to allow n control lines to control n<NUM> - n electrical components, thereby allowing a greater number of electronic elements to be controlled via a lesser number of control lines. In the depicted example, electronically functional yarns 304B and 304C each include three control lines <NUM> configured to carry electrical signals to the electronic component(s). Such control lines may be used to control six individual diode-containing circuit elements. Control lines <NUM> are shown as dashed lines to indicate that the control lines are actually located on a core of a core-sheath yarn structure, as described in more detail below.

<FIG> shows an example circuit <NUM> comprising a plurality of diode-containing circuit elements <NUM>. As described in more detail below, circuit <NUM> may be formed on a yarn core of a core/sheath yarn, and the resulting yarn may be integrated with a plurality of electronically functional and/or non-functional yarns to provide an electronically functional textile. Circuit <NUM> may schematically represent the circuit formed on weft yarns 304B and/or 304C, for example. In <FIG> each diode-containing circuit element <NUM> is shown as comprising an electronic component <NUM> in series with a diode <NUM>. For some circuit elements <NUM>, electronic component <NUM> may be discrete and separate from diode <NUM>, such as where the electronic component comprises a temperature sensor or other non-diode element. In other examples, electronic component <NUM> comprise an integrated diode junction, such as an LED.

<FIG> also illustrates how n<NUM> - n circuit elements may be controlled via n control lines using "Charlieplexing. " In this arrangement, each control line 408A, 408B, 408C is connected to a corresponding pin 410A, 410B, 410C of a controller <NUM>, and each pair of control lines is connected by a pair of diode-containing circuit elements having opposite polarities. By placing each pin <NUM> in a different one of three states (logical high, logical low, or high impedance), controller <NUM> may select the set of control lines through which current flows, as well as the direction of current flow, and thereby individually control each circuit element <NUM>. For example, controller <NUM> may activate circuit element 402A, and none of the other circuit elements, by driving control line 408A in a high logical state (e.g., +<NUM> V), driving control line 408B in a low logical state (e.g., <NUM> V), and effectively disconnecting control line 408C by placing its corresponding pin 410C in a high-impedance state. In contrast, to actuate circuit element 402B, and none of the other circuit elements, controller <NUM> may drive control line 408B in the high logical state, drive control line 408A in the low logical state, and place pin 410C in the high-impedance state. All circuit elements <NUM> may be individually controlled in this manner to provide outputs, read inputs (e.g. by sequentially reading each sensor of a plurality of sensors), and perform other suitable functions.

As described above, control lines enable the control of n<NUM> - n circuit elements. <FIG> shows another example Charlieplexed circuit <NUM> with five control lines <NUM> operable to control twenty diode-containing circuit elements <NUM>. Each circuit element <NUM> is individually controllable by a controller <NUM>, which may control a particular circuit element by setting each control line of the circuit element via its corresponding pin <NUM> to suitable logic states and setting the remaining control lines to high impedance states.

<FIG> illustrates an example electronically functional yarn <NUM> that may be incorporated into an electronically functional textile. Yarn <NUM> may represent yarns 304B and/or 304C of <FIG>, for example, and is schematically shown in a partially unraveled configuration. Yarn <NUM> comprises a yarn core <NUM> including a core strip <NUM> that runs at least a portion of a length of the yarn. Core strip <NUM> may be formed as a cut section of a conductor-clad polymer membrane on which a conductive pattern (e.g. a plurality of control lines) is formed by patterning of the conductive cladding. The conductive pattern may be formed via a suitable photolithographic process, for example. In some examples, the core strip may be <NUM> to <NUM> microns wide and <NUM> to <NUM> microns thick. In other examples, core strip <NUM> may have other dimensions, whether wider/narrower and/or thicker/thinner. In some examples, core strip <NUM> may be a section detached from a conductor-clad polymer-membrane sheet of suitable thickness. Materially, the polymer-membrane section may comprise an elastomer for desirable flexibility. The polymer-membrane section may comprise a silicone or urethane polymer, for example. In other examples, the polymer-membrane section may comprise a styrene-butadiene epoxy resin. In implementations in which a bendable, but not necessarily stretchable, yarn is desired, the polymer-membrane section may include polyethylene tetraphthalate (PET), polyimide (PI), and/or polyethylene napthalate (PEN), for example. Other polymers, both natural and synthetic, may also be used.

In the depicted example, three electrically conductive traces <NUM> are formed on the polymer-membrane section and distributed over at least a portion of the length of core strip <NUM>. In some examples, traces <NUM> may comprise copper (optionally plated with another metal or material). In some examples, traces <NUM> may be <NUM> to <NUM> microns in width (in some cases <NUM> to <NUM> microns in width), and <NUM> to <NUM> microns thick. In other examples, traces <NUM> may have any other suitable dimensions. In the example shown in <FIG>, core strip <NUM> has opposing sides, which each may support one or more electrically conductive traces. In some examples, traces <NUM> on opposing sides of the core strip <NUM> may be connected by an electrically conductive via passing through the core strip. In other examples, traces <NUM> may be arranged on one side only, and/or may have any other suitable dimensions than those described above. With three traces <NUM> arranged on core strip <NUM> as shown, <FIG> may represent an implementation of circuit <NUM> on yarn <NUM>. Any suitable number of traces may be disposed on yarn <NUM>, however, including five, as may be the case for an implementation of circuit <NUM> on the yarn. Yet other arrangements are possible, such as those in which traces are formed on more than two surfaces. For example, two or more double-sided structures (e.g., core strips) may be stacked using a dielectric adhesive, where each double-sided structure includes one or more traces arranged on each side. Conductive through-vias may electrically couple traces in different double-sided structures.

<FIG> also shows a plurality of electronic circuit elements <NUM> electrically coupled to electrically conductive traces <NUM> of core strip <NUM>, in an interior portion of yarn <NUM>. Elements <NUM>, which may include discrete or integrated electronic-circuit elements, may be coupled to traces <NUM> via an electrically conductive adhesive, reflow soldering, or other suitable method. At least one electrical terminal <NUM> is arranged at terminus <NUM> of each trace <NUM>. Terminal <NUM> enables the various electronic-circuit components of electronically functional yarn <NUM> to be addressed and/or powered (e.g., at least in part by controller <NUM> or <NUM>). In some examples, terminal <NUM> may take the form of a cut end of one of traces <NUM>, which may be cut anywhere along the length of the yarn.

Yarn core <NUM> also includes a carrier thread <NUM> to provide mechanical strength during winding, spinning, weaving, etc. In some examples, carrier thread <NUM> may comprise a plurality of wound or spun fibers or filaments. In other examples, carrier thread <NUM> may comprise a single, mechanically robust filament. Carrier thread <NUM> may be attached to core strip <NUM> in any of a variety of ways. Further, carrier thread <NUM> may span any suitable region(s) of core strip <NUM>, including but not limited to the substantial entirety of the core strip (and potentially the length of the overall yarn <NUM>). In some implementations, carrier thread <NUM> may be attached to the core strip <NUM> using a flexible adhesive, such as a suitable pressure sensitive adhesive, curable adhesive, or thermoplastic adhesive. In other implementations, carrier thread <NUM> itself may be formed from a thermoplastic material and bonded to the core strip <NUM> via the application of heat (and potentially with the application of suitable pressure). Any such bonding methods may be used at any suitable locations along the carrier thread <NUM> and core strip <NUM>. <FIG> provides a cross-sectional, schematic view of yarn core <NUM>, core strip <NUM>, and carrier thread <NUM>, in one example. In yet other examples, carrier thread <NUM> may be omitted.

Electronically functional yarn <NUM> includes one or more windings wrapped or spun around the core strip <NUM> and carrier thread <NUM> to thereby form a sheath <NUM>. The windings include electronically non-functional fibers. For clarity, <FIG> shows one such winding <NUM>, but in practice many fibers may be wound around the core strip. In other examples, a plurality of non-functional, non-fibrous filaments may be wound around core strip <NUM> in addition to the electronically non-functional fibers. Suitable electronically non-functional fibers include raw fibers of wool, flax, cotton, hemp, and synthetic polymers. Suitable non-fibrous filaments include natural silk as well as synthetics. The material composition of sheath <NUM> may be selected in view of various criteria. For examples in which yarn <NUM> includes one or more LEDs, the material composition of sheath <NUM> may be selected such that light emitted by the LED(s) is not undesirably attenuated by the sheath. Materials suitable for this type of implementation may include nylon, for example. Further, some types of yarn postreatments may be omitted to preserve desired light output, such as the application of brightening agents. These and other considerations may similarly apply to implementations in which yarn <NUM> comprises one or more sensing elements, where the congruence of sheath <NUM> with the sensing capabilities of the sensing elements is desired. In some examples, sheath <NUM> may comprise one or more yarns arranged around core strip <NUM>.

Sheath <NUM> may be electronically functional or non-functional. In electronically functional examples, the windings may include a conductive filament or thread that interfaces with one or more traces <NUM> on yarn core <NUM>. In other examples, conductive filaments may be wound around core <NUM>, then other fibers or filaments may be wound around the wrapped-core structure, thereby concealing the core and the conductive filaments wrapped around it. In still other examples, sheath <NUM> may be endowed with electrical conductivity via a posttreatment process in which, after forming yarn <NUM>, the sheath is metalized. Sheath <NUM> may be configured for any suitable purpose - as an example, the sheath may comprise a thermoconductive material and may be configured as a heat exchanger. As another example, sheath <NUM> may comprise a conductive material and may be configured as an electrostatic discharge shield. As yet another example, sheath <NUM> may comprise an electrically insulating thread wound around electronically functional core <NUM> and may electrically insulate the electronic components integrated in yarn <NUM>.

Where an electronically functional yarn comprises LEDs, attenuation of light output by the LED(s) by sheath <NUM> may be undesirable. As mentioned above, in some examples a sheath material may be selected to help reduce such attenuation. In other examples, yarn <NUM> may include one or more apertures formed over each LED, thereby providing openings for light emission. <FIG> schematically shows a cross-sectional view of a yarn <NUM> including an aperture <NUM> arranged at a location corresponding to a location of an LED <NUM>. Apertures similarly may be used for other types of components, such as for sensors where unobstructed sensing is desired (e.g. photosensors, temperature sensors, chemical sensors). Aperture <NUM> may be formed in any suitable manner, such as by localized infrared heating, high-precision blade cutting, and/or deposition of a chemical solvent. In other examples, aperture <NUM> may be formed without removing a portion of the sheath; instead, as one example, one or more operational parameters of a covering machine used to form sheaths may be controlled to form the aperture, such as turns per inch and/or a tension setting. In some examples, aperture <NUM> may be included in the design of yarn <NUM>, such that the aperture is formed along with the yarn.

<FIG> shows a flow diagram illustrating an example method <NUM> of making an electronically functional yarn. At <NUM>, an electrically conductive cladding layer of a conductor-clad polymer membrane sheet is patterned to form an array of n electrically conductive lines on the polymer sheet, wherein n is equal to or greater than three. The conductor-clad polymer sheet may comprise, for example, a flexible polymer sheet coated on one or both sides with a thin layer of a conductor such as copper. In some examples, photolithography may be used to pattern the electrically conductive surface layer of the conductor-clad polymer sheet. The photolithography process may include application of a photoresist and selective curing of the photoresist by UV irradiation through a photomask. This process may be followed by a chemical etch to remove the copper from between the traces. In other examples, a resist may be applied via a stencil and cured without the aid of a mask. In still other examples, a screen-printing technique may be used to apply and/or pattern the conductive traces onto a polymer sheet. In some examples, the patterning aspect may include an optional step in which the electrically conductive lines formed by wet etching are overplated with nickel, tin, and/or another material, to discourage oxidation, increase strength, etc. The optional overplating step may include electroplating, electroless plating, or spray coating, as examples.

As noted above, the conductor-clad polymer sheet used to form a core strip may have an electrically conductive surface layer provided on each of the first and second opposing sides. Here, method <NUM> may include an optional step <NUM> of forming a via between the electrically conductive surface layer of the first side and the electrically conductive surface layer of the second side. A via may be formed, for example, by laser ablation (laser drilling) of a small locus of the patterned polymer sheet. The ablated locus may extend from a conductive line on one side of the sheet to a conductive line on the opposite side of the sheet. The ablated hole may then be filled with solder, conductive adhesive, or the like. In other examples, die punching may be used in lieu of laser ablation.

At <NUM> of method <NUM>, a plurality of diode-containing circuit elements are attached to the n electrically conductive lines. Up to n<NUM> - n diode-containing circuit elements may be individually controlled, and more diode-containing circuit elements may be attached in instances where it is desired to activate more than one diode-containing circuit element in parallel via a same control output. The electronic components may be attached in any suitable manner, such as by using a conductive adhesive or soldering. In method <NUM>, the circuit elements and conductive lines may be encapsulated prior to further processing to avoid detachment or damage during subsequent winding of the electronically functional yarn. Suitable encapsulants may include a polyurethane, polysiloxane, and/or epoxy-amine resin that remains flexible upon curing. In some examples, encapsulation may occur at <NUM>, prior to cutting the sheet (with components attached) into sections.

At <NUM> the surface-modified polymer sheet is cut, thereby detaching a strip of the patterned polymer sheet. The strip detached in this manner still supports the n electrically conductive lines, which are distributed over at least a portion of a length of the strip, and the plurality of circuit elements arranged on the strip. Mechanical micro-machine cutting and/or laser ablation (laser machining) may be used to cut away the section, as examples. The polymer sheet may be cut in various directions - for example, the sheet may be cut in a lateral direction to obtain longitudinally separated strips. Alternatively or additionally, multiple patterned yarn cores may be formed in parallel on a common substrate, and then cut in a longitudinal direction to obtain separated strips.

While the attachment of diode-containing circuit elements to the polymer membrane at <NUM> is illustrated as taking place prior to cutting the polymer membrane at <NUM>, in other examples the circuit elements may be attached to the polymer membrane after cutting the polymer membrane.

At <NUM> of method <NUM> an optional encapsulation step may be used. Encapsulation after the cutting may be used, for example, when a continuous film of robust encapsulant over the entire surface of the core strip is desired. A plurality of strips may be cut from the patterned polymer sheet in this manner to form a plurality of yarn cores.

At <NUM> the encapsulated core strip may optionally be attached to a carrier thread, which provides mechanical robustness during subsequent spinning of the various electronically non-functional fibers and/or filaments around the core strip. In some implementations, the carrier thread may be secured to the core strip using an adhesive, such as a curable material or a pressure-sensitive adhesive. In other examples, the carrier thread may be formed from a thermoplastic material that can be bonded via heat to the core strip. Further, in some examples, the core strip may be attached to a carrier thread at a different location in the process than that shown in <FIG>.

At <NUM>, a plurality of fibers and/or filaments (as described above) are wound around the yarn core to form an electronically functional yarn.

Claim 1:
An electronically functional yarn (<NUM>), comprising:
a core (<NUM>);
a sheath (<NUM>) at least partially surrounding the core, wherein the sheath comprises one or more electronically non-functional windings (<NUM>); and
an electronic circuit (<NUM>) formed on the core, the circuit including three or more control lines (<NUM>) and more than three diode-containing circuit elements (<NUM>) controllable by the three or more control lines, each circuit element being controllable via a corresponding set of two of the three or more control lines.