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How do red-light photons and violet-light photons differ in energy?

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A horizontal gradient bar displays the visible light spectrum from violet to red, labeled with corresponding frequency in terahertz, wavelength in nanometers, and photon energy in electron volts. — light When white light is spread apart by a prism or a diffraction grating, the colours of the visible spectrum appear. The colours vary according to their wavelengths. Violet has the highest frequencies and shortest wavelengths, and red has the lowest frequencies and the longest wavelengths.

In physics, the energy of a photon is directly proportional to its frequency and inversely proportional to its wavelength, as described by the relationship $E = h ν$ (where $h$ is Planck’s constant).

Because violet light has a shorter wavelength (approximately 400 nm) and a higher frequency compared to red light (approximately 700 nm), violet-light photons possess significantly more energy than red-light photons. Specifically, the energy of visible light photons ranges from about 1.8 eV for red light to approximately 3.1 eV for violet light.12