During color calibration, certain tooling is needed to measure light output from your display. This article outlines the differences between two commonly used measurement devices for display calibration: colorimeters and spectroradiometers.

Colorimeters vs. Spectroradiometers

Colorimeters are tristimulus devices – meaning they use three different color filters (red, green, blue) to mimic the way the human eye perceives color.

Spectroradiometers as their name implies, are spectral devices – meaning they measure light as a function of wavelength. This allows them to characterize a display’s Spectral Power Distribution (SPD) or power/energy levels of a light source through a range of wavelengths. This is useful for understanding and correcting for differences in display backlight technology and counteracting errors derived from metamerism (colors that have differing SPDs appear perceptually identical under certain conditions).

Spectroradiometers feature a high degree of accuracy while sacrificing speed of measurement and portability compared to colorimeters.
 

Calibration Matrix

A calibration matrix is typically found within a colorimeter. Because colorimeters are not spectral devices, they cannot derive the difference between different backlight configurations found on modern displays (LCD, OLED, etc.). For this reason, correction or ‘calibration’ matrices are built-in to these devices to ensure more accurate measurements. One common use of spectroradiometers is to profile colorimeters for a specific display via building a calibration matrix into the colorimeter that matches the display’s specific SPD. This minimizes errors seen between generic profiles and manufacturer consistency across panels.

For more information about calibration basics, refer to our article on Display Color Calibration.