Abstract: A transflective display device (1), comprising: an array of transmissive pixels (4) and reflective pixels (12) arranged such that at least one characteristic of an image is different for the image displayed in transmissive mode compared to the image displayed in reflective mode, for example different resolution, or one mode colour and the other mode monochrome, and arranged to switch off a backlight (190) that provides illumination for the transmissive mode responsive to the ambient light level (304) exceeding a threshold level (316). The device may further, or alternatively, be arranged to drive the reflective pixels (12) in an all-black state responsive to the ambient light level (304) falling below the threshold (316). An additional threshold (318) may be used to provide a hysteresis loop (320-321).

Abstract: Physical barriers (210) are present between neighbouring pixels (200) on a circuit substrate (100) of an active-matrix electroluminescent display device, particularly with LEDs (25) of organic semiconductor materials. The invention forms these barriers (210) with metal or other electrically-conductive material (240) that serves as an interconnection between a first circuit element (21, 4, 5, 6, 140, 150, 160, T1, T2, Tm, Tg, Ch) of the circuit substrate and a second circuit element (400, 400s, 23), for example, a sensor (400s) of a sensor array supported over the pixel array. The conductive barrier material (240) is insulated (40) at the sides of the barriers adjacent to the LEDs and has an un-insulated top connection area (240t) at which the second circuit element is connected to the conductive barrier material (240).

Abstract: A field sequential colour display device has a light source arrangement (16) for providing at least two outputs (R, G, B) in sequence of different colour spectrum. The light source output intensity is controlled independently for each output; in dependence on analysis of the data for an image to be displayed. The brightness of each backlight colour output is thus adapted as a function of the image content, and this enables power savings to be obtained.

Abstract: A display controller (40), comprising: a processor (62) for providing row selection pulses (52, 54, 56) for a display comprising M rows of pixels, the row selection pulses (52, 54, 56) having respective durations (t1, t2, t3 . . . tM) that increase from the pulse (52) for row 1 to the pulse (56) for row M. The processor (62) may retime image data (72) for synchronisation with the increase in the pulse duration, for example by writing incoming data (72) in to a buffer (64) at the rate the incoming data (72) is received and reading the data out from the buffer (64) at a rate corresponding to the increase in the pulse duration. Also described is a display device comprising the display controller (40), and a method of driving the display device using the display controller (40). The increase in row selection pulse duration (t1, t2, t3 . . . tM) is arranged to correspond, with a desired level of precision, to an increasing charging time of the pixels of the rows.

Abstract: An active matrix display device having touch input functionality is provided. The device comprises a plurality of pixels arranged in a row and column array, each pixel comprising a pixel electrode (11) to which data voltages can be supplied by an associated data conductor (12) via a respective thin film transistor (13) having a drain terminal connected to the pixel electrode. The pixels each further comprise a body (30;70;80) which electrically connects the associated pixel electrode to another electrode (51;14) in response to touch-input to the pixel, the connection being detectable via the associated data conductor. The circuitry used to address the display can also be used to detect any touch-input to the display, including pressure-sensitive and optical touch-input. This advantageously eliminates the requirement for extra conductors to perform the touch-input detection.

Abstract: An active matrix LED display has a light-dependent device for detecting the brightness of the display element and threshold voltage measurement circuitry for measuring a threshold voltage of a pixel the drive transistor. Compensation for ageing of the display element is thus provided by an optical feedback path, and compensation for drive transistor threshold variations is provided by measurement of the threshold voltage. This provides a reliable compensation scheme for the threshold voltage variations, whilst also providing ageing compensation.

Abstract: In an active matrix display, each pixel has a storage capacitor for storing a voltage to be used for addressing a drive transistor. A discharge transistor is provided for discharging the storage capacitor thereby to switch off the drive transistor. The timing of this is controlled by a light-dependent device which is illuminated by the display element. The drive transistor is controlled to provide a constant light output from the display element, and the duration is controlled in dependence on the data voltage. Optical feedback is used to alter further the timing of operation of the discharge transistor to provide ageing compensation of the display element and compensation for changes in the drive transistor.

Abstract: A display device has a plurality of pixels, each pixel having a current-driven display element (2) coupled between a first conductive layer (28) and a second conductive layer (27), the second conductive layer (27) being coupled to a current supply (26) via a switchable device (12) having a thin film component (122) on a first area of a substrate (120). Each pixel further has a first capacitive device having a first capacitor plate (132) on a second area of the substrate (120), the first capacitor plate (120) being conductively coupled to the thin film component, a second capacitor plate (133) and a first insulating layer (130) between the first capacitor plate (132) and the second capacitor plate (133).

Abstract: An active miatrix electroluminescent display device has pixels using an amorphous silicon or microcrystalline silicon drive NMOS transistor (22) connected between the anode of the display element (2) and a power supply line (26). A storage capacitor (24) is connected between the anode of the display element and the gate the drive transistor (22). An amorphous silicon or microcrystalline silicon second drive NMOS transistor (30) supplies a holding voltage to the anode of the display element (2). This arrangement enables the voltage across the display element to be held while the transistor gate drive voltage is stored on the storage capacitor. This enables an accurate current source pixel circuit to he implemented using NMOS transistors.

Abstract: An active matrix display device uses an amorphous silicon drive transistor for driving a current through an LED display element. First and second capacitors are connected in series between the gate and source of the drive transistor, with a data input to the pixel provided to the junction between the first and second capacitors. The second capacitor is charged to a pixel data voltage, and a drive transistor threshold voltage is stored on the first capacitor. This pixel arrangement enables a threshold voltage to be stored on the first capacitor, and this can be done each time the pixel is addressed, thereby compensating for age-related changes in the threshold voltage.

Abstract: In an active matrix display device, particularly an AMLCD, having an array of display pixels (8) and comprising pixel electrodes (16), associated switches (22), and address lines (18, 20) carried on a first substrate (10), a common electrode (26) carried on a second substrate (12), a drive circuit (40, 80) carried on the first substrate (10) including at least one conductor line (96) providing a drive voltage for the common electrode (26) and to which the common electrode (26) is connected (92), the common electrode (26) on the second substrate is utilised to provide also electrical connection between the one conductor line (96) and at least one other circuit element (37) carried on the first substrate (10). The use of the common electrode in this way assists in avoiding problems due to resistances of connections formed on the first substrate. The connection to a storage capacitor line (37, 36) may benefit especially.

Abstract: Physical barriers (210) are present between neighbouring pixels (200) on a circuit substrate (100) of an active-matrix display device, such as an electroluminescent display formed with LEDs (25) of organic semiconductor materials. The invention forms at least parts of the barriers (210) with metal or other electrically-conductive material (240) that is insulated (40) from the LEDs but connected to the circuitry (4, 5, 6, 9, 140, 150, 160, T1, T2, Tm, Tg, Ch etc.) within the substrate (100). This conductive barrier material (240) may back up or replace, for example, matrix addressing lines (150) and/or form an additional component either within the pixel array or outside. The additional component comprising the conductive barrier material (240) is advantageously a capacitor (Ch), or an inductor (L) or transformer (W), or even an aerial.

Abstract: Physical barriers (210) are present between neighbouring pixels (200) on a circuit substrate (100) of an active-matrix electroluminescent display device, particularly with LEDs (25) of organic semi conductor materials. The invention forms these barriers (210) with metal or other electrically-conductive material (240), that is insulated (40) from the LEDs but connected circuitry within the substrate (100). This conductive barrier material (240) backs-up or replaces at least a part of the drive supply line (140,240) to which the LEDs are connected by a drive element T1. This transfers the problem of line resistance and associated voltage drop from within the circuit substrate (100), where it is severely constrained, to the much freer environment of the pixel barriers (210) on the substrate (100) where the conductive barrier material (240) can provide much lower resistance. Very large displays can be made with low voltage drops along this composite drive supply line (140,240).

Abstract: Physical barriers (210) are present between neighbouring pixels (200) on a circuit substrate (100) of an active-matrix electroluminescent display device, particularly with LEDs (25) of organic semiconductor materials. In order to reduce parasitic capacitance in the circuit substrate, the invention forms these barriers (210) with metal or other electrically-conductive material (240) that provides at least part of the signal lines (160) at a higher level than the circuit substrate (100). This conductive barrier material (240) is connected to the matrix circuitry within the substrate (100) but is insulated (40) at least at the sides adjacent to the LEDs (25). Preferably, an inter-capacitance guard line (9) is included in the circuit substrate (100) between the signal lines (160) and the circuitry in the substrate (100).

Abstract: A portable electronic device (40) comprises a display module (42) and a battery unit (44). The device has at least one further analogue input or output interface (50,52,54) (in addition to the display). The display module includes a voltage converter (48) for providing at least one voltage exceeding the battery unit voltage, and an output from the voltage converter (48) of the display module is provided to a circuit (50a, 52a, 54a) associated with the at least one further analogue input or output interface. This enables a reduction in cost and volume of the device by providing a highly integrated solution, in which a voltage converter within a display module is used also for circuitry of another interface or interfaces.