Nowadays, eye protection(myopia prevention) has become a trend. One of the principles of diffuse reflection- imaging principle of projection which effectively prevents direct rays to hurt our eyes. With the development of projection technology, an ultra-short-throw projector(laser projector) has come into being. Various kinds of fabrics are generated in order to meet different needs with an ultra-short-throw projector. PET Crystal and Fresnel fabric are the superiors of ambient light rejecting screen. We will introduce the information about these two fabrics that you can make a better decision.

PET Crystal:

PET Crystal has a special optical sawtooth structure, applies with a black and white prism, the black layer absorbs ambient light while the white slope can reflect the light from the projection. Lights of the projector from bottom to the top project to white reflective layer then reflect our eyes, ambient light from above will be absorbed by the black layer.

Here is a gif shows the characteristic of PET Crystal:

As we can see from the gif, when we overlook the screen, the color of the screen will be black(light absorbent layer) while it will be white(reflective layer) when we look up with the change of direction. The ultrashort anti-light screen PET Crystal can avoid 93% ambient light, 160 degrees wide viewing angle to present real color.

Fresnel screen:

Fresnel screen’s surface covered with big to small semicircle thread structure, this kind of structure is only sensitive with the projection light from the bottom of the circle center. It means that it only reflects the lights project from the projector. It is necessary for the circle center to aim the lens of the projector so that the light of reflection gather in a range to improve the brightness of the image.

Supernova™ STS fresnel screen, for example, it only has 100-degree viewing angle.

                                            Viewing Angle of PET Crystal                                                                                          Viewing Angle of Fresnel screen

Fresnel screen exerts a reflective principle of light regression that improves the gain of the screen, make it up to 1.2 gain, but it will decrease the viewing angle to 100 degrees, once you see the image at a bigger angle. The image gets darker. Last but not least, there is a resin protective film on the screen surface for easy cleaning, however, it will cause reflection.

                                               Real Image of Pet Crystal                                                                                                                           Real Image of Fresnel Screen

To sum up, PET crystal screen has high contrast, wide viewing angle, and no reflection. Fresnel screen has high gain, better brightness, low contrast, narrow viewing angle, and reflection.