A spectrophotometer is a laboratory instrument that measures the amount of light absorbed by a sample and is used to determine properties such as concentration or absorption patterns of substances. It is done with the use of a spectrophotometer , a device that measures the intensity of light as a beam of light passes through a sample solution. Light is a versatile element. It can be reflected, scattered, transmitted, and absorbed. Colour Difference is Key - Ensure Accuracy with our Advanced Colorimeters. Our Colorimeters for Unquestionable Accuracy. Spectrophotometry is a technique to measure the reflection or transmission of light by a material as a function of wavelength. Learn about its history, applications, types, and principles from this comprehensive article.