Panasonic explains that it is utilizing “light-modulating cells” in addition to liquid crystal cells. The challenge with LCD today is that the liquid crystals and polarizers in each pixel cell cannot adequately block light from the backlight unit, and is, as a result, unable to reach deep blacks and high contrast.
The light-modulating cells are placed between the backlight unit and the liquid crystal pixel matrix. This permits “pixel-by-pixel control of backlight intensity”, says Panasonic. However, it will also be more expensive to produce.