The pearl screen or crystal screen is one of four different screen types.
The pearl screen corresponds to screen type B and differs from the other projection surfaces
inthat the crystalline surface structure, which contains tiny glass spheres, reflects most of the projected light in the same direction from which it came. The reflected light's angle of incidence is thus the same as that of the incident light.gain factors are between 1.5 and 1.7 in the preferred direction, but only between 0.5 and 0.7 at the edge of the screen. This indicates that pearl or crystal screens have a narrower viewing angle than diffuse screens.