The nanometer, or nm, is a common unit used to describe wavelengths of light or other electromagnetic radiation such as [[UV]]. For example, green light has wavelengths of about 500-550 nm, while violet light has wavelengths of about 400-450 nm. | The nanometer, or nm, is a common unit used to describe wavelengths of light or other electromagnetic radiation such as [[UV]]. For example, green light has wavelengths of about 500-550 nm, while violet light has wavelengths of about 400-450 nm. |