The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:
Reference will now be made in detail to embodiments, which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
The LCD device 100 includes a compensation data generating part 110. The compensation data generating part 110 is inputted with the RGB source data signals from the external system 1. The compensation data generating part 110 performs arithmetic and/or logical operations, such as addition and subtraction, on the RGB source data signals to generate RGB conversion data signals and first to third compensation data signals. The RGB conversion data signals may have a digital format. The first to third compensation data signals can also have a digital format and allows the display of yellow (Y), cyan (C) and magenta (M).
The LCD device 100 includes a timing controlling part 120, a scan driving part 130 and a source driving part 140. The timing controlling part 120 is inputted with the RGB conversion data signals and the first to third compensation data signals from the compensation data generating part 110. The timing controlling part 120 outputs the RGB conversion data signals and the first to third compensation data signals. Also, the timing controlling part 120 outputs control signals to control the scan driving part 130 and the source driving part 140 in response to vertical and horizontal synchronizing signals (Vsync and Hsync, not shown) and a clock signal (not shown). The scan driving part 130 generates scan signals according to the control signals outputted from the timing controlling part 120 and outputs the scan signals according to the vertical synchronizing signal (Vsync).
The source driving part 140 is inputted with the RGB conversion data signals and the first to third compensation data signals from the timing controlling part 120. The source driving part 140 converts the RGB conversion data signals into signals having an analog format and outputs the analog data signals to a liquid crystal panel 150. The source driving part 140 outputs the RGB conversion data signals and the first to third compensation data signals according to the horizontal synchronizing signal (Hsync).
The liquid crystal panel 150 includes a plurality of pixels arranged in a matrix form. Thin film transistors are electrically connected to each of the pixels to selectively apply the RGB conversion data signals and the first to third compensation data signals to the pixels. The RGB conversion data signals and the first to third compensation data signals are applied to the pixels by switching the corresponding thin film transistors using the scan signals outputted from the scan driving part 130.
The LCD device 100 further includes a backlight unit 160. The backlight unit 160 supplies light to the liquid crystal panel 150. The operation of the backlight unit is controlled by the timing controlling part 120.
Data signals for displaying mixed colors are generated based on the RGB source data signals. A sub-frame for each mixed color is added in the frame period. Since the mixed colors are separately displayed during different sub-frames, the RGB source data signals are subtracted from the data signal values corresponding to the mixed colors. The data signals generated by this process are the RGB conversion data signals. In the first embodiment, yellow (Y), cyan (C) and magenta (M) are used as exemplary mixed colors. Selection of the mixed colors may be changed according to need of improving the color mixture property for a specific color.
As shown in
(1) R conversion data signal value={R compensation source data signal value−(minimum RG compensation source data signal value+minimum GB compensation source data signal value+minimum BR compensation source data signal value)}
(2) G conversion data signal value={G compensation source data signal value−(minimum RG compensation source data signal value+minimum GB compensation source data signal value+minimum BR compensation source data signal value)}
(3) B conversion data signal value={B compensation source data signal value−(minimum RG compensation source data signal value+minimum GB compensation source data signal value+minimum BR compensation source data signal value)}.
In an embodiment, the above data signals have a digital format. Then, the RGB conversion data signals and the first to third compensation data signals are generated by addition and subtraction operations of the RGB source data signals. Also, when a subtracted result is a negative value, for example, a data signal value of 0 is subtracted by a data signal value of 70, the subtracted result is considered as 0.
The RGB conversion data signals and the first to third compensation data signals generated by the above processes are supplied to the liquid crystal display panel 150. In other words, the RGB conversion data signals and the first to third compensation data signals are transferred to the timing controlling part 120. The timing controlling part 120 outputs the RGB conversion data signals, the first to third compensation data signals and control signals to the source driving part 140, and outputs control signals to the scan driving part 130.
The source driving part 140 may convert the data signals received from the timing controlling part 120 to analog voltages in a DAC (data-to-analog converter) using gamma reference voltages. The converted data signals are outputted to the liquid crystal panel 150 in synchronization with the scan signals from the timing controlling part 120. The light sources in the backlight unit 160 are turned on when the RGB conversion data signals and the first to third compensation data signals are inputted to the liquid crystal panel 150.
Referring back to
As shown in
According to the first embodiment of the present invention, the color mixture distortion is prevented by the generation of RGB conversion data signals and first to third compensation data signals to display yellow from RGB source data signals. Thus, the RGB source data signals have signal values, R1=100, G1=100 and B1=0, respectively. The minimum RGB source data signal value is 0 for blue. Accordingly, R, G and B compensation source data signals have signal values, R2=(100−0)=100, G2=(100−0)=100, and B2=(0−0)=0.
A minimum RG compensation source data signal value of 100 is obtained by finding the minimum between R2=100 and G2=100. Accordingly, the first compensation data signal has a value Y1=100 obtained by adding the minimum RGB source data signal value of 0 to the minimum RG compensation source data signal value of 100.
A minimum GB compensation source data signal value of 0 by finding the minimum between G2=100 and B2=0. Accordingly, the second compensation data signal has a value C1=0 obtained by adding the minimum RGB source data signal value of 0 to the minimum GB compensation source data signal value of 0.
A minimum BR compensation source data signal value of 0 is obtained by finding the minimum between B2=0 and R2=100. Accordingly, the third compensation data signal has a value of M1=0 obtained by adding the minimum RGB source data signal value of 0 to the minimum BR compensation source data signal value of 0.
For RGB conversion data signals, the minimum RGB source data signal is 0, and the R, G and B compensation source data signals have the signal values, R2=100, G2=100 and B2=0. The sum of the minimum RG compensation source data signal value, the minimum GB compensation source data signal value and the minimum BR compensation source data signal value is 100+0+0, which is 100. Thus, RGB conversion data signals of R3=0, G3=0 and B3=0 are generated by subtracting the sum of the minimum RG, GB and BR compensation source data signals from the R, G and B compensation source data signals.
Accordingly, as illustrated in
RGB conversion data signals and first to third compensation data signals are generated as follows, in accordance with the first embodiment of the present invention. The RGB source data signals have signal values, R1=100, G1=0 and B1=0, respectively. The corresponding minimum RGB source data signal value is 0. Accordingly, R, G and B compensation source data signals have signal values, R2=(100−0)=100, G2=(0−0)=0, and B2=(0−0)=0.
The minimum RG compensation source data signal, which is the minimum between R2=100 and G2=0, has a value of 0. Accordingly, the first compensation data signal, which is obtained by adding the minimum RGB source data signal value of 0 to the minimum RG compensation source data signal value of 0, has a signal value of Y1=0.
Similarly, the minimum GB compensation source data signal value, which is the minimum between G2=0 and B2=0, is also 0. Accordingly, the second compensation data signal, which is obtained by adding the minimum RGB source data signal value of 0 to the minimum GB compensation source data signal value of 0, has a signal value of C1=0.
Furthermore, the minimum BR compensation source data signal value, which is the minimum between B2=0 and R2=100, is also 0. Accordingly, the third compensation data signal, which is obtained by adding the minimum RGB source data signal value of 0 to the minimum BR compensation source data signal value of 0, also has a data signal value of M1=0.
The minimum RGB source data signal is 0, and the R, G and B compensation source data signals have the signal values, R2=100, G2=0 and B2=0. By subtracting a value of 0, (which is the minimum RG compensation source data signal value+the minimum GB compensation source data signal value+the minimum BR compensation source data signal value), from the R, G and B compensation source data signals, RGB conversion data signals having signal values, R3=100, G3=0 and B3=0, respectively, are generated.
Accordingly, the data signals, which are outputted from the compensation data generating part, have signal values, R3=100, Y1=0, G3=0, C1=0, B3=0 and M1=0, as illustrated in the graph (b). Thus, red is displayed. In the sub-frame when red is displayed, a red light source irradiates. A reference BL represents a backlight-irradiation interval.
According to the first embodiment, RGB conversion data signals and first to third compensation data signals are generated as follows to display white. The RGB source data signals have signal values, R1=100, G1=100 and B1=100, respectively. The minimum RGB source data signal value is 100. Accordingly, the R, G and B compensation source data signals have signal values, R2=(100−100)=0, G2=(100−100)=0, and B2=(100−100)=0, respectively.
The minimum RG compensation source data signal value is 0, which is the minimum between R2=0 and G2=0. Accordingly, the first compensation data signal has a value of Y1=100, which is obtained by adding the minimum RGB source data signal value of 100 to the minimum RG compensation source data signal value of 0.
The minimum GB compensation source data signal value is 0, which is the minimum between G2=0 and B2=0. Accordingly, the second compensation data signal has a value of C1=100, which is obtained by adding the minimum RGB source data signal value of 100 to the minimum GB compensation source data signal value of 0.
The minimum BR compensation source data signal value is 0, which is the minimum between B2=0 and R2=0. Accordingly, the third compensation data has a value of M1=100, which is obtained by adding the minimum RGB source data signal value of 100 to the minimum BR compensation source data signal value of 0.
The minimum RGB source data signal is 0, and the R, G and B compensation source data signals have the signal values, R2=0, G2=0 and B2=0, respectively. By subtracting a value of 0, (which is the minimum RG compensation source data signal value+the minimum GB compensation source data signal value+the minimum BR compensation source data signal value), from the R, G and B compensation source data signals, RGB conversion data signals having signal values, R3=0, G3=0 and B3=0, respectively, are generated.
Accordingly, the data signals, which are outputted from the compensation data generating part, have signal values, R3=0, Y1=100, G3=0, C1=100, B3=0 and M1=100, respectively. Thus, as illustrated in
In accordance with the first embodiment of the present invention, RGB conversion data signals and first to third compensation data signals are generated as follows to display the exemplary arbitrary color in the FSC driving mode LCD device. The RGB source data signals have signal values, R1=100, G1=60 and B1=20. Thus, the minimum RGB source data signal value is 20. Accordingly, the corresponding R, G and B compensation source data signals have signal values, R2=(100−20)=80, G2=(60−20)=40, and B2=(20−20)=0, respectively.
The minimum RG compensation source data signal value is 40, which is the minimum between R2=60 and G2=40. Accordingly, the first compensation data signal has a value of Y1=60, which is obtained by adding the minimum RGB source data signal value of 20 to the minimum RG compensation source data signal value of 40.
The minimum GB compensation source data signal value is 0, which is the minimum between G2=40 and B2=0. Accordingly, the second compensation data has a value of C1=20, which is obtained by adding the minimum RGB source data signal value of 20 to the minimum GB compensation source data signal value of 0.
The minimum BR compensation source data signal value is 0, which is the minimum between B2=0 and R2=80. Accordingly, the third compensation data signal has a signal value M1=20, which is obtained by adding the minimum RGB source data signal value of 20 to the minimum BR compensation source data signal value of 0.
The minimum RGB source data signal is 20, and the R, G and B compensation source data signals have the signal values, R2=80, G2=40 and B2=0, respectively. By subtracting a value 40, (which is the summation of the minimum RG compensation source data signal value, the minimum GB compensation source data signal value, and the minimum BR compensation source data signal value), from the R, G and B compensation source data signals, respectively, RGB conversion data signals having signal values, R3=40, G3=0 and B3=0, respectively, are generated.
Accordingly, the data signals outputted from the compensation data generating part have signal values, R3=40, Y1=60, G3=0, C1=20, B3=0 and M1=20, as illustrated in
As explained above, the FSC driving mode LCD device of the first embodiment display an image using more colors than the related art. Accordingly, color break-up and color mixture distortion are improved. Also, the reproduction rate for solid color is not reduced. Further, when displaying mixed colors including white color, at least two light sources irradiate simultaneously to emit yellow, cyan and magenta. Thus, brightness increases.
Data signals for displaying mixed colors are generated using the RGB source data signals. Sub-frames are added in the frame period to display an image in the liquid crystal panel. Since the mixed colors are separately displayed, the RGB source data signals are subtracted from the data signal values corresponding to the mixed colors. The data signals generated by this process are the RGB conversion data signals. In the second embodiment, white (W), yellow (Y), cyan (C) and magenta (M) are used as exemplary mixed colors. Selection of the mixed colors may be changed according to need of improving the color mixture property for a specific color.
The compensation data generating part 210 performs arithmetic and/or logical operations, such as addition and subtraction, on the received RGB source data signals to generate RGB conversion data signals, first to third compensation data signals, and a white data signal. The RGB conversion data signals may have a digital format. The first to third compensation data signals can also have a digital format and allows the display of yellow (Y), cyan (C) and magenta (M), respectively. The white data signal has a digital format to display white (W). The FSC driving mode LCD device 200 generates color data signals to display mixed colors including white, and supplies the generated color and white data signals to the liquid crystal panel. Accordingly, brightness is improved and color break-up are reduced.
As shown in
In accordance with the second embodiment, the mixed colors corresponding to the first to third compensation data signals and the W data signal overlap with the red, green and blue of the RGB source data signals. Thus, the RGB conversion data signals are generated by subtracting the overlapped color amounts from the RGB source data signals. For example, the RGB conversion data signals are generated, respectively, by subtracting the W data signal value and the first to third compensation data signal values from the RGB source data signals, respectively. In other words, when the W data signal value is “a”, and the first to third compensation data signal values are “b”, “c” and “d”, respectively, the RGB conversion data signal values R3, G3 and B3 are, R3={R source data signal value−(a+b+c+d)}, G3={G source data signal value−(a+b+c+d)}, and B={B source data signal value−(a+b+c+d)}.
Since the above data signals have a digital format, the RGB conversion data signals, the first to third compensation data signals and the W data signal are generated by arithmetic/logical operations, such as addition and subtraction operations of the RGB source data signals. Also, when a subtracted result is a negative value, for example, a data signal value of 0 is subtracted by a data signal value of 70, the subtracted result is considered as 0.
The RGB conversion data signals, the W data signal and the first to third compensation data signals generated by the above processes are supplied to the liquid crystal display panel. In other words, the RGB conversion data signals, the W data signal and the first to third compensation data signals are transferred to the timing controlling part. The timing controlling part outputs the RGB conversion data signals, the W data signal, the first to third compensation data signals and control signals to the source driving part, and outputs control signals to the scan driving part.
The turn-on controlling part controls one light source corresponding to each data signals for red, green and blue colors in sub-frames when the data signals for red, green and blue colors are inputted. The turn-on controller concurrently turns on two or more light sources to irradiate a mixed color light in sub-frames when the first to third compensation data signals are inputted. For example, the turn-on controlling part concurrently turns on the R and G light sources simultaneously to display Y, the G and B light sources simultaneously to display C, and the blue and red light sources simultaneously to display M. The turn-on controlling part concurrently turns on three R, G and B light sources in the sub-frame corresponding to the W data signal.
In accordance with the second embodiment of the present invention, RGB conversion data signals, a W data signal and first to third compensation data signals are generated as follows to display the exemplary arbitrary color in the FSC driving mode LCD device. The RGB source data signals have signal values, R1=100, G1=70 and B1=30. Thus, the minimum RGB source data signal value is 30. Accordingly, the W data signal has value W1=30. The corresponding R, G and B compensation source data signals have signal values, R2=(100−30)=70, G2=(70−30)=40, and B2=(30−30)=0, respectively.
The minimum RG compensation source data signal value is 40, which is the minimum between R2=70 and G2=40. Accordingly, the first compensation data signal has a value of Y1=40, which is the minimum RG compensation source data signal value of 40.
The minimum GB compensation source data signal value is 0, which is the minimum between G2=40 and B2=0. Accordingly, the second compensation data has a value of C1=0, which is the minimum GB compensation source data signal value of 0.
The minimum BR compensation source data signal value is 0, which is the minimum between B2=0 and R2=70. Accordingly, the third compensation data signal has a signal value M1=0, which is the minimum BR compensation source data signal value of 0.
The RGB source data signals have signal values, R1=100, G1=70 and B1=30. The W data signal has value W1=30. The first, second and third compensation data signals have the signal values, Y1=40, C1=0 and M1=0, respectively. By subtracting a value 70, (which is the summation of the W data signal, the first compensation data signal value, the second compensation data signal value, and the third compensation data signal value), from the RGB source data signals, respectively, RGB conversion data signals having signal values, R3=30, G3=0 and B3=0, respectively, are generated.
Accordingly, the data signals outputted from the compensation data generating part have signal values, R3=30, G3=0, B3=0, W1=30, Y1=40, C1=0 and M1=0, as illustrated in
According to the second embodiment, RGB conversion data signals, a W data signal and first to third compensation data signals are generated as follows to display white. The RGB source data signals have signal values, R1=100, G1=100 and B1=100, respectively. The minimum RGB source data signal value is 100. Accordingly, the W data signal has value W1=100. The R, G and B compensation source data signals have signal values, R2=(100−100)=0, G2=(100−100)=0, and B2=(100−100)=0, respectively.
The minimum RG compensation source data signal value is 0, which is the minimum between R2=0 and G2=0. Accordingly, the first compensation data signal has a value of Y1=0, which is the minimum RG compensation source data signal value of 0.
The minimum GB compensation source data signal value is 0, which is the minimum between G2=0 and B2=0. Accordingly, the second compensation data signal has a value of C1=0, which is the minimum GB compensation source data signal value of 0.
The minimum BR compensation source data signal value is 0, which is the minimum between B2=0 and R2=0. Accordingly, the third compensation data signal has a value of M1=0, which is the minimum BR compensation source data signal value of 0.
The RGB source data signals have signal values R1=100, G1=100 and B1=100. The W data signal has value W1=100. The first, second and third compensation data signals have the signal values, Y1=0, C1=0 and M1=0, respectively. By subtracting a value 100, (which is the summation of the W data signal, the first compensation data signal value, the second compensation data signal value, and the third compensation data signal value), from the RGB source data signals, respectively, RGB conversion data signals having signal values, R3=0, G3=0 and B3=0, respectively, are generated.
Accordingly, the data signals outputted from the compensation data generating part have signal values, R3=0, G3=0, B3=0, W1=100, Y1=0, C1=0 and M1=0, as illustrated in
RGB conversion data signals, a W data signal and first to third compensation data signals are generated as follows, in accordance with the second embodiment of the present invention. The RGB source data signals have signal values, R1=100, G1=100 and B1=0, respectively. The corresponding minimum RGB source data signal value is 0. Thus, the W data signal has a value of 0. The R, G and B compensation source data signals have signal values R2=(100−0)=100, G2=(100−0)=100, and B2=(0−0)=0, respectively.
The minimum RG compensation source data signal, which is the minimum between R2=100 and G2=100, has a value of 100. Accordingly, the first compensation data signal, which is the minimum RG compensation source data signal value of 100, has a signal value of Y1=100.
Similarly, the minimum GB compensation source data signal value, which is the minimum between G2=100 and B2=0, is 0. Accordingly, the second compensation data signal, which is the minimum GB compensation source data signal value of 0, has a signal value of C1=0.
Furthermore, the minimum BR compensation source data signal value, which is the minimum between B2=0 and R2=100, is also 0. Accordingly, the third compensation data signal, which is the minimum BR compensation source data signal value of 0, also has a data signal value of M1=0.
The RGB source data signals have signal values R1=100, G1=100 and B1=0. The W data signal has value W1=0. The first, second and third compensation data signals have the signal values, Y1=0, C1=0 and M1=0, respectively. By subtracting a value 100, (which is the summation of the W data signal, the first compensation data signal value, the second compensation data signal value, and the third compensation data signal value), from the RGB source data signals, respectively, RGB conversion data signals having signal values R3=0, G3=0 and B3=0, respectively, are generated.
Accordingly, the data signals outputted from the compensation data generating part have signal values, R3=0, G3=0, B3=0, W1=0, Y1=100, C1=0 and M1=0, as illustrated in
RGB conversion data signals, a W data signal and first to third compensation data signals are generated as follows, in accordance with the second embodiment of the present invention. The RGB source data signals have signal values, R1=100, G1=0 and B1=0, respectively. The corresponding minimum RGB source data signal value is 0. Thus, the W data signal has a value of 0. The R, G and B compensation source data signals have signal values R2=(100−0)=100, G2=(0−0)=0, and B2=(0−0)=0, respectively.
The minimum RG compensation source data signal, which is the minimum between R2=100 and G2=0, has a value of 0. Accordingly, the first compensation data signal, which is the minimum RG compensation source data signal value of 0, has a signal value of Y1=0.
Similarly, the minimum GB compensation source data signal value, which is the minimum between G2=0 and B2=0, is 0. Accordingly, the second compensation data signal, which is the minimum GB compensation source data signal value of 0, has a signal value of C1=0.
Furthermore, the minimum BR compensation source data signal value, which is the minimum between B2=0 and R2=100, is also 0. Accordingly, the third compensation data signal, which is the minimum BR compensation source data signal value of 0, also has a data signal value of M1=0.
The RGB source data signals have signal values R1=100, G1=0 and B1=0. The W data signal has value W1=0. The first, second and third compensation data signals have the signal values, Y1=0, C1=0 and M1=0, respectively. By subtracting a value 0, (which is the summation of the W data signal, the first compensation data signal value, the second compensation data signal value, and the third compensation data signal value), from the RGB source data signals, respectively, RGB conversion data signals having signal values R3=100, G3=0 and B3=0, respectively, are generated.
Accordingly, the data signals outputted from the compensation data generating part have signal values, R3=100, G3=0, B3=0, W1=0, Y1=0, C1=0 and M1=0, as illustrated in
As explained above, the FSC driving mode LCD device of the second embodiment display an image using more colors than the related art. Accordingly, color break-up and color mixture distortion are reduced. Also, color reproduction rate for solid color is improved. Further, the sub-frame displaying white is further added to increase brightness.
In accordance with another embodiment, a separate white light source may be used for the white sub-frame in place of simultaneous irradiation of red, green and blue light sources.
In accordance with another embodiment, the backlight unit can be used with another type of display device.
It will be apparent to those skilled in the art that various modifications and variations may be made in the driving method of the liquid crystal display device without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations provided they come within the scope of the appended claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| P-2006-0032159 | Apr 2006 | KR | national |