Visiblespectrum

Visiblespectrum, commonly referred to as the visible spectrum, denotes the portion of the electromagnetic spectrum that can be perceived by the human eye. It typically spans wavelengths from about 380 to 750 nanometers, though the exact bounds can vary among individuals. When white light passes through a prism, it disperses into a continuous band of colors, traditionally described as red through violet.

Physiology and perception play key roles in how the visible spectrum is experienced. The retina contains photoreceptor cells called cones that detect color, arranged in three types with sensitivity roughly corresponding to long (red), medium (green), and short (blue) wavelengths. In bright light, cone signals dominate color perception, with peak luminance sensitivity near 555 nanometers. Color experience is influenced by adaptation and context, and the same spectral distribution can appear different under varying lighting. Metamerism describes how different mixtures of wavelengths can produce the same perceived color.

Properties and terminology also distinguish spectral from non-spectral colors. Some colors, such as pure spectral colors, correspond to a single wavelength, while others (like pink or brown) arise from mixtures and do not map to a single wavelength. The visible spectrum is a subset of the broader electromagnetic spectrum and forms the basis for common color classifications; ROYGBIV is a traditional mnemonic for the order of colors.

Measurement and representation involve recording spectral power distributions and mapping them into color spaces. Tools include spectrometers and colorimetric models such as CIE XYZ and related chromaticity diagrams. Although human vision has finite resolution for color, digital devices translate spectral information into RGB representations for display and interpretation.

Applications of the visible spectrum span science, technology, and daily life, including imaging, lighting design, photography, astronomy, and art. Understanding spectral properties aids in selecting light sources, interpreting scenes, and analyzing material composition.