Colour, Gloss and Haze
Application
We essentially offer two groups of testing devices for measuring colour and haze of materials, surfaces or liquids. They are the ideal instruments for laboratory and field use.
Since the product range includes a large number of similar instruments, we will introduce the leading products in their class below. These are colorimeters for simple colour determination, spectrophotometers for high-precision colour determination and a test instrument for turbidity and transmission measurement.
The overview shows the individual products and performance for colour detection.
Spectrophotometer
The spectrophotometer is a precision optical testing device for measuring colour. For this purpose, the light intensity relative to the wavelength is determined. By illuminating the measuring surface over the spectrum from ultraviolet to infrared (360 to 780nm) of visible light, the reflectance values are determined.
Based on the measurement geometry, a spectrophotometer measures either the amount of light reflected by an object or the amount of light absorbed by the object.
Spectrophotometers can measure almost any sample: liquids, plastics, paper, metal and fabrics, paints, screens, etc.
Measurement of the quantity of light absorbed (transmitted light) is mainly used in analytical (bio)chemistry, and measurement of the quantity of light reflected has a wide range of applications in colour management, the textile industry, printing, coatings and dyes.
There are different techniques for colour analysis. Instruments with 0º/45º (or 45º/0º) measure the colour from the sample at a fixed angle and are ideal for colour measurement on smooth or matt surfaces.
Multi-angle spectrophotometers illuminate the sample at only one angle, but take measurements at several angles as if you were rotating the sample. Multi-angle instruments are ideal for measuring pigment colours and effect coatings with additives such as mica and pearlescent.
In the following we will concentrate mainly on devices with spherical geometry. They illuminate the sample under diffuse light and can perform measurements without specular component excluded (SCE) and with specular component included (SCI). They are generally used for colour measurement on structured surfaces, such as textiles, carpets and plastics, as well as glossy or mirror-like surfaces, such as metallic inks, printed films and other highly glossy surfaces.
To quantify the opacity and haze of a sample, many spectrophotometers can take measurements in transmission mode. They also take into account optical brighteners - chemical additives used in manufacturing to make products such as paper, plastics and textiles look whiter and brighter.
Modern spectrophotometers not only support a colour management strategy, but also offer absolutely reliable, precise and repeatable measurements for exchange between operators and several production sites. In the following we will introduce our top-of-the-range testing equipment. There are also a number of other variants.
> For further information see also our supplier's website CHN Spec.