8-bit/color 1024/spl times/768 microdisplay with analog in-pixel pulse width modulation and retinal averaging offset correction

Abstract

A liquid-crystal-on-silicon microdisplay based on a 1024/spl times/768 2-D pixel array fabricated in a digital 0.35 /spl mu/m CMOS process displays images with a color depth of 8-bits/color. The pixel pitch is 22 /spl mu/m and the total chip area is 214 mm/sup 2/. Pixel brightness is controlled by modulating the pulse width of the pixel voltage drive signal with an in-pixel analog pulse width modulation (PWM) circuit which utilizes human optic nerve spatio-temporal averaging to eliminate comparator offset. The 16 million transistor chip displays images at a maximum rate of 85 Hz and has a power dissipation of 200 mW from a single 3.3 V supply.