How to use a spectrophotometer measure solid colors?
As we all know, there are ten million colors that we can distinguish. The quality criterion “color” is becoming more and more important in every industry. Uniform color influence customer’s likes and dislikes. This is of particular important when the individual components of the final products are manufactured at difference company sites, or even more complicated when several supplier are involved. Nevertheless, in the end the color must be right.
Visual color perception is influenced by different color sensitivities from person to person(mood,age.etc), varying environments such as lightness and color. This is a digital world, more and more people will be more willing to believed the data rather than judgement from the manufacture, in that way, a color measuring machine is very important for the quality control department.
Color perception is depend on the interaction of three elements: light source, object and observer.
Item 1: color changes with the light source. So when we compare color difference, the illuminants have to be agreed and used. The visible spectrum is from 400 to 700nm.
Generally speaking, the important illuminants are Daylight D65, C, A,f2 & f11.
Item 2: without an observer there would be no color. Reflected light from a colored object enters the human eye through the lens and strikes the retina. And today, the observer is the spectrophotometer which stimulate the brain to produce the impression of color. To determine the sensitivity to the receptor,systematic visual tests were done by the CIE 1931 and 1964, based on the results,the degree 2 and degree10 observer were standardized, representing a small and large field of view,respectivily.
Item 3 object: Optical properties of an object are the only variables that need to be measured.
Color System combine data from three elements: light source, observer and object which is recommended by the CIE and widely used today, is the CIELAB system.
Spectrophotometer model:
There are two classess of instruments use to measure color 45/0 (it uses 45 degree circumferential illumination and 0 degree viewing perpendicular to the sample plane.such as NS800)
& sphere geometry(It illuminates the sample diffusely by means of a white coated integrating sphere such as YS series spectrophotometer )
Conclusion:
Only measurements taken under the some conditions can be compared. Therefore, it is necessary to noted the following information in a color measurement report: color instrument(geometry), illuminant / observer, color system, sample preparation.
3nh offer a complete line of benchtop and portable spectrophotometer, colorimeter and chrome meter for color measuring.
PRE : NONE NEXT : Color Basics Knowledge- Object Color Rendering Return