4K resolution
So while 4K UHD sounds like it has a pixel structures with 1/4 the area of 1080p, that does not happen with pixel shifting. Only a true 4K projector offers that level of resolution. That's why "true" 4K projectors cost so much more than 4K UHD projectors with otherwise similar feature sets. They produce smaller pixels, finer resolution, no compromising of detail or color from overlapping pixels. By comparison, the slight difference in aspect ratio between DCI and 3840×2160 pixel displays without overlap is insignificant relative to the amount of detail.
DirecTV
In November 2014, DirecTV became the first television provider to begin offering 4K ultra-high definition content. On launch, 4K content was limited to renting a small library of on-demand films, downloaded to the subscriber's Genie DVR (some 4K content can also be pre-loaded automatically to the set-top box via the Genie Recommends feature). The 4K service could also only be used on "DirecTV 4K Ready" televisions, which support RVU protocol; this was limited to selected Samsung 4K televisions released in 2014.