Abstract: A display device, for example a liquid crystal display device (1), and driving method are provided that avoid the need to provide the display device with display data (e.g. video) containing individual display settings for each pixel. The display device comprises an array of pixels (21-36, 71a-79d, 121-136) and an array of processing elements (41-48, 71-79, 141-148), each processing element being associated with a respective pixel or group of pixels. The processing elements (41-48, 71-79, 141-148) perform processing of compressed input display data at pixel level. The processing elements (41-48, 71-79, 141-148) decompress the input data to determine individual pixel settings for their associated pixel or pixels. The processing elements (41-48, 71-79, 141-148) then drive the pixels (21-36, 71a-79d ,121-136) at the individual settings. A processing element may interpolate pixel settings from input data allocated to itself and one or more neighbouring processing elements.

Abstract: In an electroluminescent display device having a plurality of display elements (12) each of which comprises a portion of a common organic electroluminescent (EL) layer (20) and first and second electrodes (18,22) on opposing sides of the EL layer, an electrical conductor (30) held at a predetermined potential is provided extending between the first electrodes (18) of adjacent display elements and in contact with the EL layer for sinking electrical current tending to flow laterally in the EL layer between the adjacent display elements. In an active matrix array device, the electrical conductors may be provided in the form of a grid extending around each display element pad electrode (18). In a passive matrix array device the electrical conductors may comprise conductor lines (50) extending between the address conductors (40) of one set.

Abstract: A matrix array device, for example, an active matrix display device, image sensor, or the like, comprises a matrix circuit (12, 14, 16, 18) carried on a flexible substrate (20) which circuit includes an array of semiconductor devices (12), such as TFTs, occupying discrete areas. Selected regions of the substrate (20) away from the semiconductor devices (12) are formed as areas of weakness to encourage flexing of the substrate to occur preferentially at those regions upon bending of the device and so reduce the risk of damage to the semiconductor devices. The regions, for example, may comprise lines of weakness (50, 52) extending between the semiconductor devices and may be formed by localised thinning of the substrate or by treating the substrate material to modify its stiffness at predetermined areas.

Abstract: In a reflective liquid crystal display device comprising on a substrate an array of reflective pixel electrodes which are each connected to the output of a respective switching device, e.g. a TFT, carried on the substrate and which are provided on an insulating layer that extends over the switching device, each pixel electrode is connected to the output of its associated switching device through a plurality of tapered contact openings in the insulating layer which form depressions in the pixel electrode surface for enhancing the pixel's light reflection characteristics. The number, shape, size and relative disposition of such openings can be varied to tailor these characteristics. Preferably, a conductive layer extends from the switching device output beneath the area of the pixel electrode for contacting the electrode at each opening and may have a rough surface resulting in asperities at the pixel electrode surface which further enhance its reflection properties.

Abstract: An active matrix electroluminescent display device comprises an array of display pixels 30 arranged in rows and columns with each row of pixels sharing a common line, and with currents through the display elements of a row of pixels passing along the common line. Error values (e) are generated to correct the drive signals (V) for each pixel in a row of pixels, to correct for the different voltages appearing on the common line. These different voltages give rise to horizontal cross talk. The error values (e) are derived by modelling a row of pixels, taking into account the drive signals applied to all pixels of the row. The error values result in updated drive signals (V′).

Abstract: A method of forming a thin film transistor structure having a bottom-gate metal region (14) separated by an insulating layer (18) from a semiconductor film (20) having a channel region and source/drain regions (22) is disclosed. The method includes a back exposure step in which the gate metal region (14) acts as a mask and as part of the process of the formation of the source/drain regions (22) in the thin film (20) at location to either side of the gate metal region (14), the self-alignment achieved by the back exposure serving to limit the current path between the source/drain region (14) and the channel region (20).

Abstract: A matrix array display device has an array of pixels (10) on a substrate (50) which each have a display element (20), for example an electroluminescent display element, and associated control circuit including a storage capacitor (36) and a light sensing element (40) connected thereto for regulating charge stored on the capacitor and responsive, for example, to light emitted from the display element so as to regulate operation of the display element. The light sensing elements (40) comprise thin film semiconductor devices each having a strip of semiconductor material (52) with laterally-spaced, doped, contact regions (53, 54) and the associated storage capacitor (36) is formed by a conductive layer (58) extending substantially transversely of the strip over one contact region with intervening dielectric material.

Abstract: A display device has an array of pixels (10) comprising light emitting display elements (20), for example EL elements, carried on a substrate (50) and associated light sensing elements (40) responsive to light emitted by the display elements. The light sensing elements each comprise a gated photosensitive thin film device such as a TFT structure or a lateral gated pin device having a semiconductor layer (52) with contact regions (53, 54) laterally spaced on the substrate and separated by a gate controlled region (55). A part of the associated display element (20) extends over the gate controlled region with an electrode (70) of the display element serving as the gate of the photosensitive device thereby ensuring good optical coupling between the display element and the photosensitive device and enabling the gate to be appropriately biased. Such an arrangement enables, for example, the provision of electro-optic feedback control in the pixel in comparatively simple manner.

Abstract: A method of fabricating an electronic device comprising a thin-film transistor, which addresses a problem of increased off-state current and reduced carrier mobility in self-aligned thin-film transistors. According to the method, a gate layer (2,46) is etched back underneath a mask layer (20,48). Following an implantation step using the mask layer as an implantation mask, the etch-back exposes implant damage which is then annealed by an energy beam (42).

Abstract: An electro-stimulation apparatus comprises an electrode system for measuring local electrical impedance. The electrode system includes a multitude of electrode pads and a counter electrode held at a reference voltage. The electrode pads and the counter electrode are assembled in an electrode unit. A particular embodiment of the electro-stimulation apparatus comprises an electronic circuit including a source group of electrode pads and a sink group of electrode pads and a source conductor for applying a first electrical quantity to electrode pads of the source group. The electronic circuit also includes a sink conductor for receiving a second electrical quantity from electrode pads of the sink group. Switching elements couple individual electrode pads of the source group to the source conductor. Other switching elements couple individual electrode pads of the sink group to the sink conductor.

Abstract: In a reflective liquid crystal display device comprising on a substrate (12) an array of reflective pixel electrodes (45) which are each connected to the output of a respective switching device (18), e.g. a TFT, carried on the substrate and which are provided on an insulating layer (40) that extends over the switching device, each pixel electrode (45) is connected to the output (31) of its associated switching device through a plurality of tapered contact openings (47) in the insulating layer (40) which form depressions (50) in the pixel electrode surface for enhancing the pixel's light reflection characteristics. The number, shape, size and relative disposition of such openings can be varied to tailor these characteristics.

Abstract: In an active matrix liquid crystal display device of the kind having an array of pixel electrodes supported on an insulating film provided over active matrix circuitry, comprising switching devices, e.g. TFTs, and address lines, carried on a substrate with each pixel electrode being connected to the output of a respective switching device through the insulating film, and in which a row or column drive circuit is integrated on the substrate peripherally of the array, problems due to resistance in power or signal conductor lines of the drive circuit are conveniently overcome by extending the insulating film thereover and forming supplementary conductor tracks from the conductive layer constituting the pixel electrodes, each track being connected to its associated underlying conductor line through the film. Such tracks can be of greater width and thickness than the conductor lines.

Abstract: The manufacture of AMLCDs and similar large-area electronic devices includes forming thin-film circuit elements (11, 12, 13, 14) on a substrate (10), with some of the process steps being self-aligned by shadow-masking. An upstanding post (20) is provided at a first area (10a) of the substrate (10) to one side of a second area (10b) where there is to be formed a thin-film circuit element (11), for example a TFT. First and second parts of the circuit element (11), for example, the TFT channel (3′) and gate (5a′), are defined by respective first and second angled exposures with beams (61, 62) from the direction of the upstanding post (20) which acts as a shadow mask for part of the second area (10b). A plurality of the upstanding posts (20) may be at least partly retained in the manufactured device, for example, as supports on which a plate (30) is mounted so as to be spaced from the substrate (10).

Abstract: A large-area electronic device, such as an AMLCD, has switching TFTs (T.sub.p) in a matrix and circuit TFTs (T.sub.s) in a peripheral drive circuit. Both the TFTs (T.sub.p, T.sub.s) comprise a field-relief region (130) which has a lower doping concentration (N-) than their drain region (113) and which is present between their channel region (111) and the drain region (113). This field-relief region (130), at least over most of its length, overlaps with the gate (121) in the circuit TFTs (T.sub.s) so as to reduce series resistance in the field-relief region (130) by conductivity modulation with the gate (121). However, the drain region (113) in the switching TFTs (T.sub.p) is offset from overlap with their gate (121) by at least most of the length of their field-relief region (130). This field-relief offset permits the switching TFTs (T.sub.p) to have a lower leakage current than the circuit TFTs (T.sub.s).

Abstract: A flat panel display or other large-area electronic device comprises at least one TFT (T1;T2) having a crystalline channel region (1) and amorphous edge regions (13) adjacent side-walls (12) of the TFT island (11). The TFT is fabricated by steps which include:(a) depositing on substrate (10) a thin film (11') of amorphous semiconductor material to provide the semiconductor material,(b) removing areas of the thin film (11') to form the side walls (12a, 12b) of each island (11),(c) forming a masking pattern 20 over the edge regions (13a, 13b) preferably on an insulating film 22, and(d) directing a laser or other energy beam (50) towards the islands (11) and the masking pattern (20) to crystallise the un-masked semiconductor material for the crystalline channel region (1), while retaining amorphous semiconductor material adjacent the side walls (12a, 12b) where the edge regions (13a, 13b) are masked from the energy beam (50) by the masking pattern (20). The resulting device structure has e.

Abstract: A capacitive sensing array device, such as a fingerprint sensing device, includes an array of individual sensing electrodes (14) covered by a layer of insulating material (40) defining a sensing surface on which a person's finger is placed, each sensing electrode, its overlying fingerprint portion and intervening insulating layer providing a capacitance in operation. The sensing electrodes are of chromium and the covering insulating material includes a thin layer of chromium oxide which offers excellent scratch resistance and can be formed conveniently by oxidation of a surface region of the sensing electrodes. In a row and column array, address lines (18) extending between rows of electrodes (14) may also include chromium and be covered by chromium oxide. Preferably, the sensing electrodes and address lines are defined from a common deposited chromium layer.

Abstract: In the manufacture of a large-area electronic device, thin-film circuit elements such as TFTs are formed with separate islands (1a,1b) of a crystallized semiconductor film (1) on a device substrate (100,101). The method includes directing an energy beam (50) towards a grid (30) of masking stripes (32) and apertures (31) formed on the semiconductor film (1), to heat the semiconductor film (1) so as to crystallize it both at the apertures (31) and under the masking stripes (32). The masking stripes (32) are located over areas of the semiconductor film (1) where channel regions (11) of the TFT are to be formed. Each aperture (31) between the masking stripes (32) has a width (S1) of less than the wavelength (.lambda.) of the energy beam (50) of step (c). The length of the channel region (11) below each masking stripe (32) is crystallized by diffraction of the energy beam (50) at the apertures as well as by thermal diffusion from the areas heated by the energy beam (50).

Abstract: A touch sensing device comprising a plurality of individually operable touch sensing elements having first and second overlapping and spaced conductive layers (12, 15) with the second conductive layer being displaceable towards the first conductive layer in response to a touch input. The device is fabricated by forming on a support a thin film multi-layer structure comprising the first and second conductive layers with an insulating layer (16) therebetween and in which the second conductive layer is provided with apertures at predetermined regions, and subjecting the structure to an etching process which removes insulating material between the conductive layers at the apertured regions via the apertures to form gaps (19). This leaves the second conductive layer (15) at each region supported in spaced relationship to the first conductive layer by the insulating layer around the periphery of the region.

Abstract: In the manufacture of liquid-crystal display devices and other large-area electronics devices, electrostatic discharge damage (ESD) of tracks and other thin-film circuit elements can result during ion implantation and/or during handling. This damage is avoided by connecting the thin-film circuitry in a charge leakage path with gateable TFT links (45). These links (45) are TFTs (45) with a common gate line (7) for applying a gate bias voltage to control current flow through the links, e.g to turn off the TFTs (45) during testing of the device circuit. In accordance with the present invention the gateable links (45) in the leakage path are removed simultaneously by applying a sufficiently high gate bias (Vg2) to the common gate line (7) to break the links (45) by evaporating at least the channel regions (6) of the TFTs. A suitable thin-film structure is chosen for the TFTs (45) to facilitate evaporating their channel regions (6) in this manner.

Abstract: A method of manufacturing a large-area electronic device such as a flat panel display, which method includes subjecting a semiconductor film on a polymer substrate to an energy beam treatment, e.g., for crystal growth or to anneal an ion implant, and masking the substrate prior to treatment to prevent exposure to the energy beam, wherein the adhesion of the film and other layers on the substrate is improved by first heating the substrate to pre-shrink it, and then depositing the layers on the pre-shrunk substrate at a lower temperature than the heating temperature.