Except for the form-factor, the most weakness of LCD compared to OLED is the low color contrast. The contrast is the luminance gap between the darkest fixel and brightest fixel in LCD. And the contrast ratio of displays is higher, our eyes feel more clear.
The display panel makers consider ‘Duel cell LCD’ for going up the contrast ratio. It is made of two LCD panels. BOE and CSOT showed the technology at SIC, held in San Jose, U.S, in May.