Measuring the perception of glossy surfaces

In many markets customers judge the quality of products by their surface appearance. The term gloss describes the perception of the shiny appearance of a surface when light is reflected from that surface. Imperfections in a surface cause some of the light to be reflected/scattered at angles away from the specular and this impacts on the visual assessment of appearance. A method has existed for measuring surface reflectance for the last 50 years, but its usefulness has been limited by an inability to equal the human eye in discerning subtleties such as haze or distinctness of reflected images. A portable instrument has now been developed to take measurements about the specular, spaced at less than three minutes of arc. This paper explains how this high resolution supports the introduction of additional indices to define haze, distinctness of image and peak specular reflectance while retaining the definition of “gloss” as described in the standard method ISO2813.