A device used to measure the amount of gloss possessed by a paper, expressed as the ratio of the amount of the paper sample's reflected light to the light falling on it as compared to a gloss standard (polished black glass) of 100 "gloss units." Gloss is measured at a determined angle from the paper's surface; for coated papers, it tends to be 15º from the paper's surface (for extremely glossy papers, best results can be obtained at 20º from the paper's surface). The glossmeter shines a light of known intensity on the paper and calculates the amount reflected back at the chosen angle of reflectance. Gloss can differ with grain direction, so readings in both the grain and cross-grain direction are typically taken. (See Gloss.)
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