The UGR in the UGR<19 Diffuser Plate is a unified glare value, which is used to judge the human eye's perception of light comfort, that is, to measure the subjective reaction of the light emitted by the lighting device in the indoor visual environment to the human eye. The psychological parameters, the magnitude of which can be calculated according to the prescribed calculation conditions using the CIE unified glare value formula.

The original industrial and civil Led Diffuser Plate design standards stipulate that the direct glare of indoor general illumination is limited according to the brightness limit curve. This limitation method is only for the glare of a single luminaire, and does not represent the total Reducing Glaring effect produced by all the luminaires in the room. Therefore, CIE proposes a formula for calculating the uniform glare value (UGR) based on the glare calculation formula of various countries. Applicable to the general lighting design of simple cubic room, the lamps are evenly spaced, the lamps are double symmetric light distribution, the observation position is generally at the midpoint of the longitudinal and transverse walls, and the line of sight is observed horizontally.

Use the following methods to prevent or reduce light curtain reflections and reflected glare:

1. Avoid installing the luminaire in the interference zone;

2. Using low gloss surface decoration materials;

3. Limit the brightness of the lamp;

Nowadays, whether in industrial or civil lighting, there are certain requirements for the glare value of indoor lighting fixtures, because it has a great influence on the comfort of the human eye, so this is also the reason why the light diffusion plate UGR<19.