Sony 4K projectors use a three-chip native 4K SXRD imaging system which is derived from the same technology used in Sony 4K cinema projectors that are found in some of the world’s best movie theaters. The SXRD acronym stands for Silicon X-tal Reflective Display, where X-tal is a common abbreviation for crystal.
This is because SXRD technology places all of the panel's transistors behind the reflective surface. So the gaps between pixels are barely visible when projected on the screen.
It's an LCoS projection system (liquid crystal on silicon). This technology not only increases contrast and color depth. It also dramatically reduces the "screen door effect" which is caused by gaps or inactive areas between pixels.
This is because SXRD technology places all of the panel's transistors behind the reflective surface. So the gaps between pixels are barely visible when projected on the screen.
There are three SXRD panels, one for each of the primary colors (red, green, and blue). There are two native 4K SXRD panels available in Sony projectors. The 0.74-inch 4K SXRD panels have 8.8 million pixels (4096 x 2160) which is the same resolution as your favorite 4K movie theater projector. In 2022, Sony introduced models with 0.61" 4K UHD panels with 8.3 million pixels.
In addition to about 7% more resolution, cinematic 4K content also has a different aspect ratio than 4K UHD. However, since most consumer 4K content is distributed in 4K UHD (3840X2160) resolution in a 16x9 aspect ratio the additional horizontal resolution is zoomed off the screen, so it is usually not used.
This is important to remember when setting up a Sony 4K projector equipped with 0.74" SXRD panels on a 16x9 screen. Since the projector's native aspect ratio is wider than 16x9, you can't use the solid outer lines of the test pattern to align the screen since it has a 17x9 aspect.
The new native 0.61-inch 4K UHD SXRD panels can faithfully reproduce all 8.3 million pixels found in the 4K UHD (3840x2160) SDR and HDR content you watch every day. The result is a more compact/lighter chassis with no wasted resolution or brightness.
Many manufacturers sell pixel shifting HD (1920 x 1080) projectors that can accept 4K content. Small type and fine details that can't be discerned on a basic 1080p projector can often be resolved with pixel shifting.
In many situations, content (including movies) lacks enough fine detail or is viewed so far away that the difference between 4K and pixel shifting cannot be perceived. It is only when you do a side-by-side comparison using highly detailed content between a true 4K projector versus a 2K pixel-shifting projector that the resolution difference is truly noticeable. While a pixel-shifting 2K projector can accept 4K content, the projector's native resolution is only 2.3 MP, it won't be as sharp or as detailed as a true 4K projector (8.8 MP resolution).
The images below show the resolution difference between a Sony 4K SXRD unit and an HD projector utilizing pixel shifting when native 4K content is displayed.