Title: Electromagnetic spectrum
Content: is not relevant. White light is a combination of lights of different wavelengths in the visible spectrum. Passing white light through a prism splits it up into the several colors of light observed in the visible spectrum between 400 nm and 780 nm. If radiation having a frequency in the visible region of the EM spectrum reflects off an object, say, a bowl of fruit, and then strikes the eyes, this results in visual perception of the scene. The brain's visual system processes the multitude of reflected frequencies into different shades and hues, and through this insufficiently-understood psychophysical phenomenon, most

Title: White
Content: with only two wavelengths, for instance by mixing light from a red and cyan laser or yellow and blue lasers. This light will however have very few practical applications since color rendering of objects will be greatly distorted. The fact that light sources with vastly different spectral power distributions can result in a similar sensory experience is due to the way the light is processed by the visual system. One color that arises from two different spectral power distributions is called a metamerism. Many of the light sources that emit white light emit light at almost all visible wavelengths (sun

Title: White
Content: could be broken up into its composite colors by passing it through a prism, then using a second prism to reassemble them. Before Newton, most scientists believed that white was the fundamental color of light. White light can be generated by the sun, by stars, or by earthbound sources such as fluorescent lamps, white LEDs and incandescent bulbs. On the screen of a color television or computer, white is produced by mixing the primary colors of light: red, green and blue (RGB) at full intensity, a process called additive mixing (see image below). White light can be fabricated using light

Title: Spectrum
Content: with its own brightness or intensity. A rainbow, or prism, sends these component colors in different directions, making them individually visible at different angles. A graph of the intensity plotted against the frequency (showing the brightness of each color) is the frequency spectrum of the light. When all the visible frequencies are present equally, the perceived color of the light is white, and the spectrum is a flat line. Therefore, flat-line spectra in general are often referred to as "white", whether they represent light or another type of wave phenomenon (sound, for example, or vibration in a structure). In radio

Title: On Vision and Colors
Content: darken into black. If the remainder is only partially inactive, then the color loses its energy by mixing with gray. If the activity of the retina is divided without a remainder, or if the remainder is active, then a color and its spectrum (afterimage) are bright or pale. When such a color and its spectrum are united, then the eye sees pure light or white. For example, the mixture of bright or pale red and green on the same retinal spot results in the impression there of light or white. White cannot be produced by mixing colored pigments. With colors

Question: How many colors are there in the spectrum when white light is separated?
Answer: Seven