The diffuser sheet is used to interfere with the propagation of light, regardless of the original design of the light distribution curve is how many degrees, as long as the diffuser sheet it will make the beam angle to 160 ~ 176 °.

The larger the beam angle, the lower the illumination, and some will also produce a filtering effect - so that some of the wavelengths can not penetrate, resulting in color shift, such as in the surface again light interference treatment (for example: sanding, betting pattern), the light transmission rate will be even lower due to the natural phenomenon of geometric optics.

Therefore, the substrate used to make the diffuser sheet should be made of materials with lower refractive index, so that the interference with light is reduced.

The main role of the diffuser sheet

(1) to break up the light flux, so that the light is evenly distributed (part of the composite diffuser sheet in addition to make light uniformity, but also to control the angle of emission).

(2) Support the backlight architecture and protect the optical material below from damage.

The working principle of diffuser sheet

The larger the beam angle of the diffuser sheet, the lower the illumination, some will also produce filtering, so that some of the wavelengths can not penetrate, resulting in color shift, such as in the surface of the re-light interference treatment (for example: sanding, betting pattern), light transmission rate due to the natural phenomenon of geometric optics is even lower.

So the substrate used to make the diffuser sheet should be used the lower the refractive index the better, the lower the interference with light will be.