• Unified Glare Rating (UGR)

A psychometric parameter used by The Commission Internationale de L’Eclairage (CIE) to measure the subjective response of people’s eye discomfort of light emitted by a lighting device in a visual environment

  • Glare Rating (GR)

A psychometric parameter used by The Commission Internationale de L’Eclairage (CIE) to measure the subjective response of people’s eye discomfort of light emitted by a lighting device in a gymnasium and other outdoor lighting fixtures.

  • Glare by Reflection

Glare caused by reflection in the field of view, and in particular, the glare generated by the reflected image when viewed near the line of sight.

  • Veiling Reflection

The specular reflection of the visual object, which reduces the contrast of the visual object so that it is difficult to see the detail in part or in whole.

  • Shielding Angleof Luminaire

The angle between the light plane of the light source and the line of sight that just can not see the luminous point.

  • Colour Rendering

The light source exhibits the characteristics of the object color as compared to a reference standard light source.

  • Colour Rendering Index

Measurement of color rendering of light sources. Expressed by the matching degree of the object under the measured light source than in the reference color.

  • General Colour Rendering Index

The average value of the color rendering index of the light source from the first to the eighth standard color samples specified by the Commission Internationale de L’Eclairage (CIE). Known as the color rendering index, the symbol is Ra.

  • Special Colour Rendering Index

The average value of the color rendering index of the light source from the ninth to the fifth standard color samples specified by the Commission Internationale de L’Eclairage (CIE). The symbol is Ri.