What is a Colorimeter? Types of Colorimeters

A Colorimeter is a light-sensitive instrument that measures how much color an object or substance absorbs. It determines color based on the red, blue and green components of light absorbed by an object or sample, just like the human eye. When light passes through a medium, a portion of the light is absorbed, and as a result, the amount of light reflected by the medium is reduced. A Colorimeter can measure the change so the user can analyze the concentration of a specific substance in that medium. The device works according to Beer-Lambert's law, which states that the absorption of light transmitted through a medium is directly proportional to the concentration of the medium.

type

There are many different types of Colorimeters, including those used to measure the density of primary colors and those used to measure the reflection and transmission of colors. Styles include digital (also known as laboratory) and portable. Digital versions are often used for sampling in a laboratory setting, or in the classroom for educational purposes. Take the portable version with you to test things like water and soil samples in the field, no matter the environmental conditions.

A Spectrophotometer , a type of light meter that measures light intensity, is often combined with a Colorimeter, but it is technically a different device. Both rely on Beer-Lambert's law to calculate the concentration of a substance in a solution, but they do it in different ways. Colorimeters measure only the red, green, and blue colors of light, while Spectrophotometer s can measure the intensity of any wavelength of visible light. In general, Spectrophotometer s are more complex and more robust than most Colorimeters. They should be handled with extreme care and require periodic recalibration.

How a Colorimeter Works

At its most basic, a Colorimeter works by passing light of a specific wavelength through a solution and then measuring the light that passes through the other side. In most cases, the more concentrated the solution, the more light is absorbed, which can be seen in the difference between the origin of the light and the light after it passes through the solution. To find the concentration of an unknown sample, first prepare and test several samples of known concentration in solution. These are then plotted on a graph with concentration on one axis and absorbance on the other to create a calibration curve; when testing unknown samples, the results are compared to known samples on the curve to determine the concentration. Some types of Colorimeters automatically create a calibration curve based on an initial calibration.

use

Colorimeters are used in a variety of industries and environments. A small, portable device that analyzes color contrast and brightness on a television or computer screen, allowing the user to adjust settings to obtain a very good quality image. In the printing industry, a Colorimeter is an essential element in a color management system. Other printing industry applications include checking the quality of electronic components and paper pulp and measuring the quality of printing inks.

Diamond dealers use Colorimeters to measure the optical properties of gemstones. In cosmetic terms, the device is used to measure the sun protection factor of products applied to the skin. Colorimeters can analyze skin color and tooth color to help diagnose certain diseases, and hospitals even use some types of this device to test the concentration of hemoglobin in the blood.