So, why exactly is it that color e-ink displays try to make every micro-capsule capable of switching to any of the supported colors; rather than laying (groups of) CMYK micro-capsules out in a subpixel-like arrangement, and then wiring them to the substrate such that each of the CMYK "bitplanes" forms an independently-addressed display signal?
Sure, it'd look like badly-registered offset printing, but that only matters for small up-close displays, not large far-away displays. (And you could fix the registration with a precisely-cast diffuser layer, convolving each subpixel-cluster.)
If this was for reading rather than imagery, and you wanted to have true blacks, you could also just step one level forward in e-ink technology, and have the colored micro-capsule groups be just dual-tone (the capsule's color plus black), giving you {C+K, Y+K, M+K, K} bitplanes.
Are e-ink display manufacturers just imprecise in the way they deposit the capsules into the panel, making it impossible to address individual capsules? (If so, that seems like something that could be solved pretty easily with modern photolithography processes, e.g. etching onto the backing electrode a grid of "buckets" for individual micro-capsules to fall into.)
Sure, it'd look like badly-registered offset printing, but that only matters for small up-close displays, not large far-away displays. (And you could fix the registration with a precisely-cast diffuser layer, convolving each subpixel-cluster.)
If this was for reading rather than imagery, and you wanted to have true blacks, you could also just step one level forward in e-ink technology, and have the colored micro-capsule groups be just dual-tone (the capsule's color plus black), giving you {C+K, Y+K, M+K, K} bitplanes.
Are e-ink display manufacturers just imprecise in the way they deposit the capsules into the panel, making it impossible to address individual capsules? (If so, that seems like something that could be solved pretty easily with modern photolithography processes, e.g. etching onto the backing electrode a grid of "buckets" for individual micro-capsules to fall into.)