white light

optics

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July 15, 2026

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White light is a combination of all the colors in the visible spectrum. When white light passes through a prism, it separates into its constituent colors, forming a spectrum. This occurs because each color, corresponding to a different wavelength, is refracted at a slightly different angle. Shorter wavelengths, like violet, bend the most, while longer wavelengths, like red, bend the least. The visible spectrum, which humans can see, ranges from violet to red. The electromagnetic spectrum encompasses all forms of electromagnetic radiation, including visible light, radio waves, and X-rays.1234

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prism
…ordinary triangular prism can separate white light into its constituent colours, called a spectrum. Each colour, or wavelength, making up the white light is bent, or refracted, a different amount; the shorter wavelengths (those toward the violet end of the spectrum) are bent the most, and the longer wavelengths (those…
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…ordinary triangular prism can separate white light into its constituent colours, called a spectrum. Each colour, or wavelength, making up the white light is bent, or refracted, a different amount; the shorter wavelengths (those toward the violet end of the spectrum) are bent the most, and the longer wavelengths (those…
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colour
The nature of colour
…these spectral colours re-created the white light. Although he recognized that the spectrum was continuous, Newton used the seven colour names red, orange, yellow, green, blue, indigo, and violet for segments of the spectrum by analogy with the seven notes of the musical scale.
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…these spectral colours re-created the white light. Although he recognized that the spectrum was continuous, Newton used the seven colour names red, orange, yellow, green, blue, indigo, and violet for segments of the spectrum by analogy with the seven notes of the musical scale.
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