What is the wavelength range of visible light?

The wavelength range of visible light is indeed from 400 to 700 nanometers. This range encompasses the spectrum of light that can be perceived by the human eye, which includes colors from violet at the lower end (around 400 nm) to red at the higher end (around 700 nm).

Within this range, each segment corresponds to different colors of light—violet, blue, green, yellow, orange, and red. The significance of this range is not only fundamental to human vision but also crucial for various applications in optoelectronics, such as lighting, displays, and optical communication technologies.

In contrast, the other ranges listed either fall below or above the visible spectrum. Wavelengths below 400 nanometers correspond to ultraviolet light, which is not visible and can be harmful, while wavelengths above 700 nanometers belong to the infrared region, which is also invisible to the human eye but is used in various technologies, including remote sensing and thermal imaging.