Abstract: A system for reading a meter is provided. The meter comprises a visual display behind by a transparent cover, the visual display comprising one or more indicators each representing a sub-value and together representing a metered value measured by the meter. The system comprises an imaging unit comprising an imaging device and an adhesive configured to facilitate mounting of the imaging unit over the cover of the meter such that the imaging device faces the visual display, and a processor configured to recognize values represented by the indicators are imaged and calculate, based thereon, the metered value.

Abstract: A cholesteric liquid crystal display device comprises three cells each comprising a layer of cholesteric liquid crystal material and an electrode arrangement capable of providing independent driving of a plurality of pixels across the layer of cholesteric liquid crystal material by respective drive signals. A drive circuit applies a respective drive signal to each pixel to drive the pixel into states which are variable to provide a reflectance varying within a predetermined range of reflectances. The drive signals involve a combination of two drive schemes to provide reflectances in different portions of the range.

Abstract: A cholesteric liquid crystal display device (24) comprises three stacked cells (10R, 10G, 10B), each comprising a layer of cholesteric liquid crystal material (19) and an electrode arrangement (13, 14) capable of providing independent driving of a plurality of pixels across the layer of cholesteric liquid crystal material by respective drive signals. The display device has a drive circuit (22) arranged to apply respective drive signals to each pixel in successive cycles of predetermined duration. When providing a high reflectance, the drive signal comprises makes use of drive pulses (50) shaped to drive the pixel into the homeotropic state. When providing a low reflectance, the drive signal includes a number of perturbation pulses (61) which are sufficiently short and sufficiently spaced from each other that the pixel is driven into a transient state having a lower reflectance than the planar state.

Abstract: A cholesteric liquid crystal display device comprises three cells each comprising a layer of cholesteric liquid crystal material and an electrode arrangement capable of providing independent driving of a plurality of pixels across the layer of cholesteric liquid crystal material by respective drive signals. A drive circuit applies a respective drive signal to each pixel to drive the pixel into states which are variable to provide a reflectance varying within a predetermined range of reflectances. The drive signals involve a combination of two drive schemes to provide reflectances in different portions of the range.