"The Colorsoft is based on E Ink’s Kaleido technology but uses an entirely new display stack for Kindles, all the way back to a newly designed oxide backplane that makes it easier for E Ink panel’s tiny bits of ink to move around quickly. The E Ink world has been working on similar tech for a while, and Amazon thinks it’s the key to making color work well. The Colorsoft has new LED pixels, and a new way of shining light through them individually to enhance colors. It’s also brighter than ever, to help the whole thing feel more vivid. Some of this tech also helped the new Paperwhite turn pages faster and easier, but it was designed to make Colorsoft work."
https://www.aboutamazon.com/news/devices/kindle-color-specs-...
"...Kindle Colorsoft Signature Edition packs a suite of innovations that make every hue and shade pop.
Those include custom formulated coatings between the display layers to enhance the color, a light guide with micro-deflectors to minimize stray light, and an ultra-thin coating in the display stack to improve optical performance. We built the display on an oxide backplane for sharper contrast, faster page turns, and better image quality."