Display control method and apparatus for ferroelectric liquid crystal panel

Claim 2

A display control method for a ferroelectric liquid crystal panel (21) as claimed in claim 1, wherein "bright" state data and "dark" state data are set as display data (DATA), and when the picture elements (Aij) are rewritten from a dark state to a bright state, a rewriting bright voltage (C) is applied to the corresponding signal electrode (Sj), when the picture elements (Aij) are rewritten from the bright state to the dark state, a rewriting dark voltage (D) is applied to the corresponding signal electrode (Sj), and when the picture elements (Aij) are not rewritten, a non-rewriting voltage (G) is applied to the corresponding signal electrode (Sj), and furthermore, a first-half waveform and a later-half waveform of the non-selective voltage (B) are respectively selected equally to a first-half waveform and a later-half waveform, which can not rewrite the picture elements (Aij) by combining with the selective voltage (A), of either the rewriting dark voltage (D) or the rewriting bright voltage (C),

Claim 3

A display control apparatus for a ferroelectric liquid crystal panel (21), interposing a ferroelectric liquid crystal (9) between plural scanning electrodes (Li) and plural signal electrodes (Sj) which are arranged in the directions intersecting each other, using the ferroelectric liquid crystal (9) at intersections of the scanning electrodes (Li) and signal electrodes (Sj) as picture elements (Aij), applying a signal voltage of a waveform corresponding to display data (DATA) to the signal electrode (Sj), and applying a selective voltage (A) of a waveform which can rewrite a display state of the picture elements (Aij) on the electrode to the scanning electrode (Li) in linear order, and at the same time, until the selective voltage (A) is applied again to the same scanning electrode (Li) after one frame, applying a non-selective voltage (B) which can not rewrite a display state of the picture elements (Aij) repetitively at timing of applying the selective voltage (A) to the other scanning electrodes (Li), wherein comprising: a frame memory (25) for display data for storing the display data (DATA) for one picture screen to be displayed in respective picture elements (Aij) in the following frame; a frame memory (27) for difference reference for storing difference identification data (Rx) for one picture screen indicating the difference between the display data displayed at present and the display data stored in the frame memory (25); a line memory (26) corresponding respectively to each of the scanning electrodes (Li), and storing line difference identification data (SAME) which indicates whether there is even one data indication the difference in the difference identification data (Rx) of the frame memory (27) for difference reference corresponding to the picture elements (Aij) on the scanning electrode (Li); scanning electrode selective means (30) which, during the selective voltage (A) is applied to the scanning electrode (Li), checks line difference identification data (SAME) of the line memory (26) corresponding to each of the scanning electrodes (L) following the scanning electrode (Li) in linear order, decides to apply the selective voltage (A) to the corresponding scanning electrode (Li) when the line difference identification data (SAME) is data indicating the difference, and when data indicating the difference is not found as the line difference identification data (SAME), selects whether to decide to apply the selective voltage (A) only to the scanning electrode (Li) corresponding, to some of the line difference identification data (SAME) among them, or the decide to apply the selective voltage (A) to neither of the scanning electrode (Li); and data output means (30) which, in response to display data (DATA) of the frame memory (25) for display data and difference identification data (Rx) of the frame memory (27) for difference reference, gives the display data (DATA) corresponding to the picture elements (Aij) on the scanning electrode (Li) decided to be selected by the scanning electrode selective means (30), to the signal electrode (Sj) side of the ferroelectric liquid crystal panel (21) in synchronism with selection of the scanning electrode (Li).

Claim 4

A display control apparatus for a ferroelectric liquid crystal panel (21) as claimed in claim 3, wherein comprising signal electrode driving means (32) in which "bright" state data and "dark" state data are set as display data (DATA), and to apply a rewriting bright voltage (C) to the corresponding signal electrode (Sj), when rewriting the picture elements (Aij) from a dark state to a bright state, to apply a rewriting dark voltage (D) to the corresponding signal electrode (Sj), when rewriting the picture elements (Aij) from the bright state to the dark state, and to apply a non-rewriting voltage (G) to the corresponding signal electrode (Sj) when non-rewriting the picture elements (Aij), and furthermore, a first-half waveform and a later-half waveform of the non-selective voltage (B) are selected respectively equally to a first-half waveform and a later-half waveform, which can not rewrite the picture element (Aij) by combining with the selective voltage (A), of either the rewriting dark voltage (D) or the rewriting bright voltage (C).

Claim 5

A controller for a matrix display, the controller comprising a first memory for storing display data to be displayed during a first display cycle, a second memory for storing display data to be displayed during a second display cycle, a line memory for storing data representing a relationship between the display data in the first memory and in the second memory, and control circuitry for controlling the outputting of data from the first memory and the second memory in dependence on the data in the line memory, thereby to reduce the length of time required to update a frame of data displayed on the display.

Claim 7

A display control apparatus in which display data is repeatedly supplied for updating of a display on a line-by-line basis, the control apparatus being arranged to compare data to be output for display during the next display frame with data output for display during the current display frame, and to suppress scanning of a display line in the next frame where a predetermined relationship is found to exist between the compared data.

Claim 8

A display control apparatus as claimed in claim 7, further arranged to update data in a scanning suppressed display line when said predetermined relationship is found to exist between the compared data for several display frame periods.