A glossmeter (also gloss meter) is an instrument which is used to measure specular reflection gloss of a surface. Gloss is determined by projecting a beam of light at a fixed intensity and angle onto a surface and measuring the amount of reflected light at an equal but opposite angle.
The gloss meter provides a quantifiable way of measuring gloss intensity ensuring consistency of measurement by defining the precise illumination and viewing conditions.[6] The configuration of both illumination source and observation reception angles allows measurement over a small range of the overall reflection angle. The measurement results of a glossmeter are related to the amount of reflected light from a black glass standard with a defined refractive index. The ratio of reflected to incident light for the specimen, compared to the ratio for the gloss standard, is recorded as gloss units (GU).
Measurement angle refers to the angle between the incident light and the perpendicular. Three measurement angles (20°, 60°, and 85°) are specified to cover the majority of industrial coatings applications. The angle is selected based on the anticipated gloss range, as shown in the following table.
Gloss Range | 60° Value | Measure with | Notes |
High Gloss | >70 GU | 20° | If measurement exceeds 70 GU, change test setup to 20° |
Medium Gloss | 10 - 70 GU | 60° | / |
Low Gloss | <10 GU | 85° | If measurement is less than 10 GU, change test setup to 85° |
For example, if the measurement made at 60° is greater than 70 GU, the measurement angle should be changed to 20° to optimise measurement accuracy. Three types of instruments are available on the market: 60° single angle instruments, a combination of 20° and 60° and one type that combines 20°, 60° and 85°.
For measuring surface gloss, we have two models - NHG60 and NHG268 gloss meter.
NHG268 gloss meter features with 20, 60 and 85° angle, which can test material with high gloss (0-2000Gu), and universally apply to paint, ink, stoving varnish, coating, wood products; marble, granite, vitrified polished tile, pottery brick and porcelain; plastic, paper; hardware industries, etc. for gloss measurement and gloss data transmission.
NHG60 gloss meter features with 60° angle, manufactured according to ISO2813 and GB/T 9754. It is also compatible with the standards of ASTM D523, ASTM D2457. NHG60 conforms to JJG696 first class gloss meter working requirement, corresponding with CIE 1931(2°) under CIE C light source.