Gloss Meters

Gloss Meters and Reflection

Measuring the gloss of a surface in a meaningful manner is performed by an instrument called Gloss Meter. Shining a known light at an angle and receiving the reflection of that light of a surface and the amount of the reflection quantifies the gloss of that surface.

Measurement of the gloss is a relative measurement which is always referenced to a reflective Standard which is normally a black shiny block with a known reflective index. The ratio of the reflected light of the to the incident light of the device under test, and comparison of that with the Black Standard artifact is the gloss of the Device Under Test.

A number of measurement angles are specified to cover most of the industrial applications as defined below.

Range	60° Value	Angle of Light in The Instrument
High	Greater than 70 GU	20°
Medium	Between 10 GU and 70 GU	60°
Low	Less than 10 GU	85°

There is also 45 degree (for anodized Aluminium) and 75 degree (for printed materials) angles of incidents but they are for highly specialized applications and may not be normally part of instruments currently sold as commercial Gloss Meters.

The Units are GU (Gloss Unit)

A Highly polished surface, which would form the Reference Standard of the unit, has approximately 100 GU at a specified angle of incident. For a totally matte area, the unit would have 0 GU

Universal International Standards and Their Applications

Comparison of Standards for Gloss Measurement
Standard	20°	60°	85°	45°	75°
	Low Gloss	Medium Gloss	High Gloss	Medium Gloss	Low Gloss
	Coatings, plastics & related materials			Ceramics	Paper
ASTM C346				X
ASTM D523	X	X	X
ASTM C584		X
ASTM D2457	X	X		X
BS3900 D5	X	X	X
DIN 67530	X	X	X
DIN EN ISO 2813	X	X	X
EN ISO 7668	X	X	X	X
JI Z 8741	X	X	X	X	X
TAPPI T480					X

The Test Equipment & Glossmeter Calibration Specialists
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