A field‐sequential‐color display with a local‐primary‐desaturation backlight scheme

Abstract

Abstract— Field‐sequential‐color technology eliminates the need for color filters in liquid‐crystal displays (LCDs) and results in significant power savings and higher resolution. But the LCD suffers from color breakup, which degrades image quality and limits practical applications. By controlling the backlight temporally and spatially, a so‐called local‐primary‐desaturation (LPD) backlight scheme was developed and implemented in a 180‐Hz optically compensated bend (OCB) mode LCD equipped with a backlight consisting of a matrix of light‐emitting diodes (LEDs). It restores image quality by suppressing color breakup and saves power because it has no color filter and uses local dimming. A perceptual experiment was implemented for verification, and the results showed that a field‐sequential‐color display with a local‐primary‐desaturation backlight reduced the color breakup from very annoying to not annoying and even invisible.

Image content adaptive color breakup index for field sequential color displays using a dominant visual saliency method

“…2. Next, 10 reference images with relatively simple structures were selected from previous studies of color breakup visibility, [7][8][9][10][11][12][14][15][16][17][18][19][20][21][22][23][24] as Images 16 to 25. From Fig.…”

“…3(c). 9,10 In this manner, three new fields, F1' to F3' in Fig. 3(b), were derived, resulting in obviously suppressed color breakup in Fig.…”

“…Therefore, FSC displays suffer from an important drawback: color breakup. 1,[7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] Figure 1(c) illustrates the basic mechanism of color breakup and a representation of a distorted retinal image containing the color breakup, which appears as rainbow-like fringes that disturb an observer's viewing. In particular, the saccade-induced color breakup is much more severe than the smooth-pursuit-induced breakup due to the increased speed of eye movements and is thus of greater concern for FSC displays.…”

“…In particular, the saccade-induced color breakup is much more severe than the smooth-pursuit-induced breakup due to the increased speed of eye movements and is thus of greater concern for FSC displays. [9][10][11][12][13][14][15] As color breakup degrades image quality, causes discomfort to observers, and consequently impairs the application of FSC displays, a number of studies have been dedicated to this field, [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] which can be roughly grouped into two research lines. The first line of research seeks approaches that can suppress the color breakup.…”

“…The first line of research seeks approaches that can suppress the color breakup. These approaches include using a high field rate, 7,8 desaturating the driving fields, [9][10][11][12] rearranging the image content across the driving fields, 13,14 and compensating for moving images (dedicated for smooth-pursuit-induced color breakup). 15,16 The second line of research seeks to develop an objective index that can accurately predict the perceptual color breakup visibility.…”