What type of light does a pulse oximeter utilize for measuring oxygen saturation?

A pulse oximeter utilizes infrared and red light for measuring oxygen saturation in the blood. The device works by emitting these two specific wavelengths of light through a body part, usually a fingertip or earlobe, and then measuring the amount of light that passes through the tissue.

Hemoglobin, the protein in red blood cells that carries oxygen, absorbs light differently depending on whether it is oxygenated or deoxygenated. Oxygenated hemoglobin absorbs more infrared light, while deoxygenated hemoglobin absorbs more red light. By analyzing the absorption of these two wavelengths, the pulse oximeter can calculate the ratio of oxygenated to deoxygenated hemoglobin, which is displayed as a percentage of oxygen saturation.

This technology is effective because the different absorption characteristics of oxygenated and deoxygenated hemoglobin allow for a non-invasive measurement of blood oxygen levels, making pulse oximeters valuable tools in clinical settings for monitoring respiratory and cardiovascular health.