Patent ID: 8907878

Claim:
A liquid crystal display device comprising: pixels each including first to fourth subpixels having four different colors, respectively, the first to fourth subpixels being arranged in a two-by-two matrix, the first subpixel being placed in the first row and the first column, the second subpixel being placed in the first row and the second column, the third subpixel being placed in the second row and the second column, the fourth subpixel being placed in the second row and the first column, in displaying a font (i) subjected to subpixel rendering premised on a pixel composed of three subpixels having three different colors, respectively, the three subpixels being arranged in three columns of stripes, and (ii) specified, regarding a predetermined pixel falling on a portion of a character edge, that the subpixel in the first column of stripes takes on a tone Tx, that the subpixel in the second column of stripes takes on a tone Ty, and that the subpixel in the third column of stripes takes on a tone Tz, said liquid crystal display device specifying, regarding the predetermined pixel, that the first subpixel takes on a tone which is obtained by rounding off a first value which is equal to α×(Tx×⅔+Ty×⅓), that the second subpixel takes on a tone which is obtained by rounding off a second value which is equal to β×(Ty×⅓+Tz×⅔), that the third subpixel takes on a tone which is obtained by rounding off a third value which is equal to γ×(Ty×⅓+Tz×⅔), and that the fourth subpixel takes on a tone which is obtained by rounding off a fourth value which is equal to δ×(Tx×⅔+Ty×⅓), the first to fourth subpixels displaying identical tones with a luminance ratio of L1:L2:L3:L4, where L1 is the luminance of the first subpixel, L2 is the luminance of the second subpixel, L3 is the luminance of the third subpixel, and L4 is the luminance of the fourth subpixel, and α=2×L4/(L1+L4), β=2×L3/(L2+L3), γ=2×L2/(L2+L3), and δ=2×L1/(L1+L4).