摘要:
A cyclic rail-stabilized method of driving an electrophoretic display device (1), wherein a substantially dc-balanced driving waveform is used to effect the various required optical transitions. The driving waveform consists of a plurality of picture potential differences (20), which cause the charged particles (6) of the electrophoretic device (1) to cyclically between extreme optical positions in a single optical path, irrespective of the image sequence required to be displayed, i.e. in order to display each grey scale, it is necessary for the particles (6) to first pass through one of the extreme optical states. In order to minimise the effects of dwell time on the image quality and minimise, or even eliminate, the need to consider image history, shaking pulses (10) are generated immediately prior to each picture potential difference (20).
摘要:
An electrophoretic display, in which a driving method is employed whereby a sequence of discrete picture potential differences in the form of a driving waveform is supplied for enabling the charged particles (6) of the display to occupy a position for displaying an image, the position being one of a number of positions between the electrodes (3, 4). The driving waveform consists of a sequence of image update signals including a picture potential difference, the image update signals being separated by dwell times, and the method includes the step of generating one or more shaking pulses during the dwell times. Such shaking pulses may be generated immediately after each image update signal or they may comprise regular shaking pulses generated at predetermined intervals along the waveform.
摘要:
In a first display mode, only the information in a first sub-area (W1) of the display screen of a bi-stable matrix display (100) has to be updated. In a second display mode, the information in a second sub-area (W2) of the display screen has to be updated. The information in the first sub-area (W1) is displayed using optical states which require first drive voltage waveforms (DV1) having a maximum duration equal to a first image update period (IUP1). The information in the second area (W2) is displayed using optical states which require second drive voltage waveforms (DV2) having a maximum duration equal to a second image update period (IUP2). The optical states allowed to be used during the first mode are selected to obtain a first image update period (IUP1) which is shorter than the second image update period (IUP2). In this manner, the refresh rate of the information in the first area (W1) is higher than the refresh rate in the second area (W2).
摘要:
The electrophoretic display panel has an electrophoretic medium having charged particles, a plurality of picture elements, electrodes associated with each picture element for receiving a potential difference, and drive means. The drive means are arranged for controlling the potential difference of each of the plurality of picture elements to be a potential difference for enabling the particles to occupy the position corresponding to image information. For the display panel to be able to provide a smoother change-over from one image to another, the drive means are arranged for providing, during a portion of the image transition period, different starting times for application of the potential differences within the duration of the portion of the transition period for potential differences having a duration less than the maximum duration of the portion of the image transition period.
摘要:
An electrophoretic display panel and a method for driving an electrophoretic display panel in which the drive pulse, i.e. the grey scale pulse, to bring an element from a preceding optical state to an optical state is split in more than one sub-pulses. A more gradual introduction of the grey scale is thereby achieved reducing the suddenness of the transition form one image to another. Preferably application of the grey scale potential differences is preceded by application of reset pulses in which case the preceding optical state is an extreme optical state.
摘要:
An image is updated on a bi-stable display (310) such as an electrophoretic display by applying a drive waveform (900,920,940, 960; 1000, 1020,1040, 1060; 1100, 1120, 1140, 1160; 1220, 1240, 1260) with a compensating impulse (C) to at least one pixel (2) in the display. An energy of the compensating impulse depends on the image holding time, and is sufficient to restore the display to an original, pre-drift, brightness level. In one approach, the energy of the compensating impulse is determined as a predetermined function of the image holding time. In another approach, data defining different waveforms for respective different image holding times is provided in respective different look-up tables, and the data from one of the tables is selected according to the image holding time for driving the display. The compensating impulse may be provided in different portions of the drive waveform.
摘要:
A technique for driving a bi-stable display (310) such as an electrophoretic display with reduced cross talk, including reduced image retention and dithering ghosting. Drive waveforms are aligned so that, during an image update period, image transitions (500, 600, 700, 800, 900) between substantially similar optical states (e.g., black-to-black) are terminated substantially later than image transitions (520, 620, 720, 920) between substantially different optical states (e.g., black-to-white). Additionally, a drive pulse in the waveforms for the transitions between the similar states compensates for cross talk caused by a drive pulse in the waveforms for the transitions between the different states. The waveforms include at least one extreme drive pulse (ED, ED1, ED2, ED3) and an additional pulse (A) of opposite polarity.
摘要:
A cyclic rail-stabilized method of driving an electrophoretic display device (1), wherein a substantially dc-balanced waveform is used to effect various required optical transitions. The driving waveform consists of a sequence of picture potential differences, which cause the charged particles of the electrophoretic display device (1) to move cyclically between extreme optical positions in a single path, irrespective of the image sequence required to be displayed, except in the case where the desired optical transition is from an intermediate position (or grey scale) to the extreme optical position (or rail state) closest to that intermediate position, in which case the optical transition is effected substantially directly by means of a single voltage pulse (20) which is substantially equal in amplitude and duration, but of opposite polarity, to the voltage pulse (30) required to effect an original optical transition from the rail state to that grey scale.
摘要:
The present inventions relates to electrophoretic displays that are switchable between a grayscale updating mode (502) and a monochrome updating mode (501). The monochrome updating mode (501) provides for extreme pixel states only (e.g. black and white), whereas the grayscale updating mode (501) provides for intermediate grayscale pixels states as well. According to the present invention, a suitably selected transition signal (504) is applied when switching from the grayscale updating mode (502) to the monochrome updating mode (501). The transition signal (504) involves a drive pulse that serves to reduce the level of remnant DC voltage otherwise occurring in each pixel due to differences in the grayscale updating mode (502) and the monochrome updating mode (501).
摘要:
An image is updated on a bi-stable display (310) such as an electrophoretic display by providing separate scaling functions (SF1, SF2) for scaling a duration of a reset pulse (R) and a duration of a driving pulse (D) in a drive waveform based on temperature (335). An absolute value of a slope with varying temperatures of the scaling factor (SF 1) for the reset pulse (R) is significantly greater than that of the scaling factor (SF2) for the driving pulse (D), while both scaling factors increase with decreasing temperature. Image update time (IUT) is significantly reduced at lower temperatures, while a range of variation of IUT across all temperatures is also reduced. Scaling functions (SF3, SF4) may also be used for scaling a duration of a help reset pulse (H) and/or a duration of one or more shaking pulses (SH1, SH2).