The resolution of LED projector is expressed by multiplying the horizontal pixels of the picture by the vertical pixels. The resolution of LED projector does not refer to the resolution of the signal that LED projector can receive, but refers to the physical resolution of its core light engine (LED chip, LCD panel, LCOS panel, etc.). Although the projector can usually receive signals with multiple resolutions, when the signal resolution is higher than the physical resolution of the projector, the details of the picture will be obviously lost. Short-focus projection, as its name implies, is a short-focus LED projector. The biggest advantage of short focal length LED projector is that the projection distance required to realize the same size picture is shorter. This kind of LED projector no longer needs a large space scene when projecting pictures, so it is widely welcomed by users such as small and medium-sized enterprises and education market. For home users, short-focus LED projectors are equally important, especially for small living rooms.