The working principle of ultra-short focus:

Ultra-short-throw laser projector refers to a projector with a short focal length of the lens and a laser as a light source. Compared with traditional telephoto or short-throw projectors,
The main difference between them is that they project images of the same size and require different distances.


The effect of the ultra-short-throw projector on the ALR screen：

Because the projection distance of the ultra-short-focus projector is very short, if it is projected on the ALR screen, the projected picture will be uneven, and the brightness of the picture will weaken in concentric circles from the bottom of the screen, forming a condensing effect, the viewing effect and its not good


Ust alr screen is standard on ultra-short throw projectors:

Screen Material Features
Ultra Short Throw Ambient Light Rejecting Screen Material The interference light source above is absorbed by the TPU special prism, and the light source projected by the laser TV below is reflected in parallel.

Therefore, although the ultra-short-throw projector projects at a short distance, all the light will be absorbed by the curtain, forming a good projection picture.