Arguably one of the most exciting presentations at SID was Ricoh’s three-layer CMY electrochromic display. Why was this so exciting? First, the white state reflectance was 70% (altough black state was not fully black yet). Second, the colors and gamut were larger than any other technology presented. Third, the stacked display used a common electrolyte, which coupled all three layers to a single backplane. This eliminates many of the optical losses in CMY stacking.
Only two substrates were used, a first ever for stacked e-Paper. Although slow (it took seconds to refresh) the grayscale and color gamut were striking for a first demo. I am still astonished at how 3 layers can be stacked and addressed between just two substrates. Ricoh reported that each layer is only ~ 2 µm thick, and when questioned in the session, claimed 20,000 cycles of operation. Akira Suzuki of Ricoh has been seen at every display conference for as long as I can remember, perhaps assessing what technologies Ricoh should pursue. Looks like its first major bet may now be played. Jason Heikenfeld