Abstract: A method of controlling the colour balance of a video signal which comprises green, red and blue channel singals. Pixels are identified which have a green intensity within a peak intensity band. For these pixels, the red and blue intensities are examined to identify pixel subsets which are within respective red and blue peak bands. If the red and or blue peak bands are greater than the green peak band the gain of the red and/or blue channel(s) is increased. If the red and/or blue peak bands are lower than the green peak band, red and/or blue peak bands are determined for the entire video frame and are compared with the green peak band. If the red and/or blue peak bands for the entire frame are lower than that for the green channel, the gain of the red and/or blue channel(s) is increased.

Abstract: A method and apparatus for aligning an optical lens to the imaging array of an imaging system is disclosed. An integrated circuit die implements an imaging circuit and at least one z-height bump. An optical lens formed by injection molding has a lens portion for focusing an image onto the imaging circuit and an alignment portion for engaging the z-height bumps. A tape automated bonding tape carries the integrated circuit die and is aligned to the optical lens.

Abstract: A matrix array image sensor integrated circuit chip is provided including horizontal and vertical scanning means with the sensor cells within columns of the array being associated with an analogue charge sense amplifier. The analogue charge sense amplifier includes a first amplifier in the form of an inverting charge integrator which provides a preliminary detection of the charge accumulated in the sensing cell by integrating the charge to produce a voltage which is capacitively stored in a voltage storage means. The sensing cell may then be reset by control logic while it is isolated from the stored voltage which is in turn selectively sampled using a switch to read out through a second amplifier stage to be provided as an output from the integrated circuit chip. A method for operation of the device in processing an image read cycle is also provided.

Abstract: The design and testing of integrated circuits in wafer form for production faults, in the absence of irradiation, is described. This is achieved by fabricating test circuits on each wafer at the periphery of the sensor array. In a preferred arrangement, two test circuits are fabricated on each wafer; one for testing the word lines and the other for testing the bit lines and individual sensing sites. The test circuits are controlled by external signals to input predetermined patterns of data to the array and the array output patterns are compared with the input patterns to assess the level of production faults.

Abstract: A method of authenticating a person by comparing information from a currently taken skin-pattern with stored information from a previously taken skin-pattern is characterized in that the currently taken skin-pattern is produced on a contact surface, an image of the print of the skin pattern on the contact surface is projected onto a photo-detector device (20), the intensity variations of the print image in at least one region thereof impinging on the photo-detector device is assessed in digital form in a multiplicity of different sub-regions of the or each said region to create (in unit 21) a first digital signal train, a second digital train is derived from the stored skin pattern information (in store 23) and the first and second signal trains are compared (in 24) to determine the degree of coincidence therebetween, an assessment of the determined degree being used to decide (on indicator 27) whether the currently-taken and stored skin patterns are sufficiently similar to authenticate the person.