Abstract: A method of driving an active matrix electro-wetting on dielectric (AM-EWOD) device comprises (i) setting a reference electrode to a first reference voltage; (ii) writing a set of data to array element electrodes of array elements of the device; and (iii) either (a) maintaining the voltages written to the array element electrodes until a time t0 or (b) re-writing the set of data N?1 times (where N?2). The reference electrode is then set to a second reference voltage different from the first reference voltage, and features (i) to (iii) are repeated. When the data are first written, there is a delay between the time when the voltage on the reference electrode is transitioned and the time when a given array element is next written with data.

Abstract: A microfluidic system includes: an electro-wetting on dielectric (EWOD) cartridge having an element array configured to receive liquid droplets, the element array including individual array elements each including array element circuity comprising sensing circuitry that is integrated into the array element circuitry; a microfluidic instrument that is configured to receive the EWOD cartridge and having an electrically conductive locator that is external to the EWOD cartridge; and a control system configured perform electrowetting operations by controlling actuation voltages applied to the element array to perform manipulation operations as to liquid droplets present on the element array. The control system further is configured to read an output from the sensing circuitry, determine a position of the locator relative to the element array based on the output, and determine a misalignment of the EWOD cartridge relative to the microfluidic instrument based on the position of the locator.

Abstract: A method of partitioning droplets from a fluid reservoir containing particles provides a non-Poissonian distribution of dispensed droplets containing a desired number of particles.

Abstract: An AM-EWOD device includes a plurality of array elements arranged in an array of rows and columns, each of the array elements including array element circuitry, an element electrode, and a reference electrode. The array element circuitry includes actuation circuitry configured to apply actuation voltages to the element and/or reference electrodes for actuating the array element, and impedance sensor circuitry configured to sense impedance at the array element electrode to determine a droplet or device property at the array element, the impedance sensor circuitry comprising a sensor capacitor and a sensor readout transistor that outputs an output current for sensing. The sensor capacitor is electrically connected to a gate of the sensor readout transistor such that during a sensing phase a voltage perturbation is coupled through the sensor capacitor (and possibly other circuit elements) to the gate of the sensor readout transistor.

Abstract: An AM-EWOD device includes a plurality of array elements arranged in an array of rows and columns; each column including a column addressing line that applies control signals to a corresponding column of array elements, and each row including a row addressing line that applies control signals to a corresponding row of array elements; each array element including an element electrode for receiving an actuation voltage and a switch transistor, wherein the switch transistor is electrically connected between the column addressing line and the element electrode and is switched by the row addressing line; and a column detection circuit comprising an addressing circuit that applies an electrical perturbation during a sensing operation to the column addressing line of an array element being sensed, and a measuring circuit that measures an output signal from one of the column addressing lines, wherein the output signal varies based upon a capacitance present at the element electrode.

Abstract: A method of operating an active matrix electro-wetting on dielectric (AM-EWOD) device provides for enhanced mutual capacitance sensing using integrated impedance sensing circuitry. Array element circuitry of each array element includes actuation circuitry configured to apply actuation voltages to the array element electrode for actuating the array element, and impedance sensor circuitry integrated into the array element circuitry and configured to sense impedance at the array element electrode. The method of operating includes the steps of: perturbing a voltage applied to the array element electrode of a first array element; coupling the voltage perturbation to the array element electrode of a second array element different from the first array element; and measuring the output current from the sensor readout transistor of the second array element for sensing in response to the voltage perturbation.

Abstract: A method of driving an element of an active matrix electro-wetting on dielectric (AM-EWOD) device comprise applying a first alternating voltage to a reference electrode of the AM-EWOD device; and either (i) applying to the element electrode a second alternating voltage that has the same frequency as the first alternating voltage and that is out of phase with the first alternating voltage or (ii) holding the element electrode in a high impedance state. The effect of applying the second alternating voltage to the element electrode is to put the element in an actuated state in which the element is configured to actuate any liquid droplet present in the element, while the effect of holding the element electrode in the high impedance state is to put the element in a non-actuated state.

Abstract: An AM-EWOD device comprises: first and second substrates (72,36); first and second array element electrodes (38A, 38B) disposed on the first substrate (72) and defining first and second array elements in the AM-EWOD device; a reference electrode (28) disposed on the first substrate (72); a sensor; and a reference electrode drive circuit (50). The reference electrode drive circuit (50) is configured to drive the reference electrode with a first voltage waveform for actuating an array element or with a second voltage waveform different from the first voltage waveform when performing a sensing operation.

Abstract: A pixel circuit acts as a sensing element in a sensing device. The pixel circuit includes a sensing electrode, a first gate electrically connected to the sensing electrode, a second gate in electrical communication with the first gate, and a readout device that is electrically connected to the second gate. An input voltage applied to the sensing electrode is amplified between the first gate and the second gate, the amplification being measured as an output signal from the readout device to perform a sensing operation. For example, the output signal may be relatable to pH, analyte measurements, or other properties of sample liquids analyzed by the sensing device. A sensing device may include multiple pixels disposed on a substrate, each pixel including said pixel circuit. Driver circuits controlled by control electronics are configured to generate signals that selectively address the pixels and to read out voltages at the sensing electrodes.

Abstract: An active matrix electro-wetting on dielectric (AM-EWOD) device includes a plurality of array elements arranged in an array, each array element including array element circuitry, an element electrode, and a reference electrode. The array element circuitry includes an actuation circuit configured to apply actuation voltages to the electrodes, and an impedance sensor circuit configured to sense impedance at the array element electrode to determine a droplet property. The actuation circuitry includes a memory capacitor for storing voltage data corresponding to either an actuated state or an unactuated state of the array element, and an input applied to the memory capacitor operates to effect an operation of the impedance sensor circuit. Such input may isolate the array element from the actuation voltage during operation of the impedance sensor circuit, and the memory capacitor may operate as part of the impedance sensor circuit as a reference capacitor for determining the droplet property.

Abstract: An active matrix electro-wetting on dielectric (AM-EWOD) device has an optically black array element structure to enhance optical detection of constituents within a liquid droplet. The AM-EWOD device includes a thin film transistor (TFT) substrate assembly having a hydrophobic layer; thin film electronics having a plurality of array elements arranged in an array of rows and columns, each of the array elements including an array element electrode and a TFT device; and an optically black material disposed between a plane of the TFT device and the hydrophobic layer. The TFT substrate assembly further includes a planarization structure that includes a component having the optically black material. The planarization structure has a planarization component disposed between the TFT device and the array element electrode, and an ionic barrier disposed between the array element electrode and the hydrophobic coating. The planarization component or the ionic barrier includes the optically black material.

Abstract: A control method and related apparatus are disclosed for controlling actuation voltages applied to array elements of an element array on an electrowetting on dielectric (EWOD) device, wherein test metrics are determined and employed for optimizing subsequent droplet manipulation operations. The control method includes the steps of: receiving a liquid droplet onto the element array; applying an electrowetting actuation pattern of actuation voltages to actuate the droplet to modify a footprint of the droplet from a first state having an initial footprint to a second state having a modified footprint; sensing the modified footprint with a sensor; determining a test metric from sensing the modified footprint indicative of one or more droplet properties based on a droplet response of the liquid droplet to the electrowetting actuation pattern; and controlling actuation voltages applied to the array elements based on the test metric.

Abstract: An AM-EWOD device includes a plurality of array elements arranged in an array of rows and columns, each of the array elements including array element circuitry, an element electrode, and a reference electrode. The array element circuitry includes actuation circuitry that applies actuation voltages to the element and reference electrodes, and impedance sensor circuitry that senses impedance at the array element electrode to determine a droplet property at the array element. At least one component of the impedance sensor circuitry is a shared component that is shared between more than one of the array elements. The shared component may include a shared sensor readout transistor that passes a sensor current to a sensor output line, or a shared reset transistor that applies a reset voltage to a gate of the shared sensor readout transistor, with such components being shared by array elements in adjacent rows.

Abstract: Methods and apparatus for ultrasound imaging using ultrasound sensor elements comprising thin film transistors. Specifically, ultrasound elements for use in a two dimensional array of ultrasound elements, two dimensional arrays of ultrasound elements, ultrasound sensor element array assemblies, ultrasound imaging devices and methods of performing an ultrasound scan using a two dimensional array of ultrasound elements. A sensor element comprises: an ultrasound transducer, a transmit circuit configured to provide an electrical signal to the transducer for output of an ultrasound signal; and a receive circuit configured to receive an electrical signal from the transducer, based on a received reflected ultrasound signal, wherein the transmit and receive circuits each comprise one or more thin film transistors.

Abstract: An EWOD device includes opposing substrates defining a gap and each including an insulating surface facing the gap. Array elements include electrode elements to which actuation voltages are applied. A pre-charging structure defines a channel in fluid communication with the gap wherein the channel receives an input of a fluid reservoir for generation of the liquid droplet, and the pre-charging structure includes an electrical element electrically exposed to the channel. The electrical element pre-charges the fluid reservoir within the channel, and a portion of the gap containing the liquid droplet spaced apart from the channel is electrically isolated from the electrical element such that the liquid droplet is at a floating electrical potential when located within said portion of the gap. The electrical element may be an electrode portion that is exposed to the channel, or an externally connected pre-charging element inserted into the channel.

Abstract: A microfluidic system includes an electrowetting on dielectric (EWOD) device comprising an array of elements that are actuatable for manipulation of a liquid droplet within the EWOD device. The system has a pattern generator that generates an actuation pattern for actuating a portion of the elements in the array of elements, and a signal generator that generates voltage signals for actuating elements in the array of elements in accordance with the actuation pattern. The pattern generator generates an actuation pattern in which voltage signals applied to elements in at least part of a region at or adjacent to a contact line of the droplet are different from voltage signals applied to elements that are not in the part of the region at or adjacent to the contact line. The system further may include a sensor for sensing the droplet contact line constituting a boundary of the liquid droplet.

Abstract: An active matrix electro-wetting on dielectric (AM-EWOD) device includes a plurality of array elements arranged in an array, each array element including array element circuitry, an element electrode, and a reference electrode. The array element circuitry includes an actuation circuit configured to apply actuation voltages to the electrodes, and an impedance sensor circuit configured to sense impedance at the array element electrode to determine a droplet property. The actuation circuitry includes a memory capacitor for storing voltage data corresponding to either an actuated state or an unactuated state of the array element, and an input applied to the memory capacitor operates to effect an operation of the impedance sensor circuit. Such input may isolate the array element from the actuation voltage during operation of the impedance sensor circuit, and the memory capacitor may operate as part of the impedance sensor circuit as a reference capacitor for determining the droplet property.

Abstract: An EWOD device includes opposing substrates defining a gap and each including an insulating surface facing the gap. Array elements include electrode elements to which actuation voltages are applied. A pre-charging structure defines a channel in fluid communication with the gap wherein the channel receives an input of a fluid reservoir for generation of the liquid droplet, and the pre-charging structure includes an electrical element electrically exposed to the channel. The electrical element pre-charges the fluid reservoir within the channel, and a portion of the gap containing the liquid droplet spaced apart from the channel is electrically isolated from the electrical element such that the liquid droplet is at a floating electrical potential when located within said portion of the gap. The electrical element may be an electrode portion that is exposed to the channel, or an externally connected pre-charging element inserted into the channel.

Abstract: A pixel circuit acts as a sensing element in a sensing device. The pixel circuit includes a sensing electrode, a first gate electrically connected to the sensing electrode, a second gate in electrical communication with the first gate, and a readout device that is electrically connected to the second gate. An input voltage applied to the sensing electrode is amplified between the first gate and the second gate, the amplification being measured as an output signal from the readout device to perform a sensing operation. For example, the output signal may be relatable to pH, analyte measurements, or other properties of sample liquids analyzed by the sensing device. A sensing device may include multiple pixels disposed on a substrate, each pixel including said pixel circuit. Driver circuits controlled by control electronics are configured to generate signals that selectively address the pixels and to read out voltages at the sensing electrodes.

Abstract: An active matrix electro-wetting on dielectric (AM-EWOD) device includes a plurality of array elements arranged in an array, each array element including array element circuitry, an element electrode, and a reference electrode. The array element circuitry includes an actuation circuit configured to apply actuation voltages to the electrodes, and an impedance sensor circuit configured to sense impedance at the array element electrode to determine a droplet property. The actuation circuitry includes a memory capacitor for storing voltage data corresponding to either an actuated state or an unactuated state of the array element, and an input applied to the memory capacitor operates to effect an operation of the impedance sensor circuit. Such input may isolate the array element from the actuation voltage during operation of the impedance sensor circuit, and the memory capacitor may operate as part of the impedance sensor circuit as a reference capacitor for determining the droplet property.