Liquid crystal device having improved-response-characteristic drivability
View Patent ↗A liquid crystal display device in which the time necessary for luminance to change from application of a different gray-scale voltage exceeds one frame period in relation to the response as a luminance change time of the liquid crystal. The liquid crystal display device includes a signal control circuit for preventing the content of a preceding frame from being displayed as an after-image and preventing also deterioration of image quality. The signal control circuit includes a frame memory for delaying by one frame the first display data inputted from the external device, an arithmetic operation circuit for comparing the second display data stored in the frame memory and delayed by one frame with the first display data, and an addition/subtraction circuit for adding and subtracting correction data outputted by the arithmetic operation circuit to and from the first display data.
1. A display device comprising:
a display panel having a plurality of pixels arranged in a matrix form;
a signal drive circuit generating a tone voltage corresponding to display data;
a scan drive circuit generating a scan voltage for selecting a row of a pixel to which the tone voltage is applied;
tone voltage lines coupled to said signal drive circuit and said plurality of pixels, for transferring said tone voltage form said signal drive circuit to said plurality of pixels;
scan voltage lines coupled to said scan drive circuit and said plurality of pixels, for transferring said scan voltage from said scan drive circuit to said plurality of pixels; and
a correction circuit which corrects said display data of (N+1) frame based on a differential between the display data of N-th frame and the display data of N+1-th frame and a tilt coefficient of correction data to post-change display data relative to before-change display data,
wherein said tilt coefficient when the display data changes from a dark tone to a bright tone is different from said tilt coefficient when the display data changes from a bright tone to a dark tone.
2. A display device comprising:
a display panel having a plurality of pixels arranged in a matrix form;
a signal drive circuit generating a tone voltage corresponding to display data;
a scan drive circuit generating a scan voltage for selecting a row of a pixel to which the tone voltage is applied;
tone voltage lines coupled to said signal drive circuit and said plurality of pixels, for transferring the tone voltage from said signal drive circuit to said plurality of pixels;
scan voltage lines coupled to said scan drive circuit and said plurality of pixels, for transferring said scan voltage from said scan drive circuit to said plurality of pixels; and
a correction circuit which corrects said display data in response to a change in the display data,
wherein, when the display data changes from a dark tone to a bright tone, said correction circuit adds a first correction data to the display data,
wherein, when the display data changes from a bright tone to a dark tone, said correction circuit subtracts a second correction data from the display data, and
wherein the first correction data is larger than the second correction data.
3. A display device according to claim 2 , wherein:
when the display data of an N-th frame is the dark tone and the display data of N+1-th frame is the bright tone, said correction circuit adds the first correction data to the display data of the N+1-th frame, and
when the display data of the N-th frame is the bright tone and the display data of the N+1-th frame is the dark tone, said correction circuit subtracts the second correction data from the display data of the N+1-th frame.
4. A display device according to claim 2 , wherein, when the display data represents a moving picture, said correction circuit corrects the display data corresponding to the post-change tone.
5. A display device comprising:
a display panel having a plurality of pixels arranged in a matrix form;
a signal driver arranged to generate a tone voltage corresponding to display data to said plurality of pixels;
a scan driver arranged to generate a scan voltage to said plurality of pixels for selecting a row of a pixel to which the tone voltage is applied; and
a correction circuit for correcting display data in a current frame input to said signal driver, based on a differential between display data of a preceding frame and display data of the current frame;
wherein, when the display data changes from a dark tone to a bright tone, said correction circuit adds a first correction data to the display data,
wherein, when the display data changes from a bright tone to a dark tone, said correction circuit subtracts a second correction data from the display data, and
wherein the first correction data is larger than the second correction data.
6. A display device according to claim 5 , wherein:
when the display data of the preceding frame is the dark tone and the display data of the current frame is the bright tone, said correction circuit adds the first correction data to the display data of the current frame, and
when the display data of the preceding frame is the bright tone and the display data of the current frame is the dark tone, said correction circuit subtracts the second correction data from the display data of the current frame.
7. A display device according to claim 5 , wherein, when the display data represents a moving picture, said correction circuit corrects the display data of the current frame.