What is the range of visible light in nanometers?

The range of visible light is defined as the portion of the electromagnetic spectrum that can be detected by the human eye. This range is approximately 400 nanometers (nm) to 700 nanometers. Within this spectrum, shorter wavelengths correspond to colors like violet and blue, while longer wavelengths correspond to colors like red.

Understanding the significance of this range is crucial in various fields, including laser technology and phototherapy, because it influences how light interacts with biological tissues. For instance, lasers that emit light within this visible spectrum can be effectively used for therapeutic purposes, as they are more likely to be absorbed by cellular components.

The other ranges mentioned do not fall within the visible spectrum. The ranges below 400 nm (like ultraviolet light) are not visible to the human eye, while those above 700 nm (like infrared light) also fall outside of visible perception. Thus, the choice indicating 400 nm to 700 nm accurately describes the visible light range.