Frame sequential miniature silicon display using mixed-mode twisted nematic liquid crystal

We present a mixed-mode twisted nematic (MTN) silicon display integrated with 4-bit digital data drivers. With high bandwidth of the digital data driver, pixel access time of less than 10 ns was achieved. Digital gray-scale addressing technique, which utilizes multiple fields per frame, synchronous field voltages and weighted field time, was applied to increase gray scale from 4 to 8 bits. Chromatic characterization of the display using 3-color-in-1 LED as light source was performed. Contrast ratios on pixel array were 49, 32 and 21, respectively, for red, green and blue colors at 3 V root-mean-squared voltage. It was observed that frame inversion gave rise to higher contrast ratio, white column inversion was less color dispersive. Using color sequential technique, we have demonstrated 4 bits per color for this highly integrated MTN display.