The harmonics of lightwaves drawn to scale, showing how the different waves interact with each other. The λ/2 (1/2 wavelength) harmonics are perfectly in sync with each other, but all other colors in the visual spectrum fall between λ and λ/2. Wavelengths that are separated by λ/4 are opposites, falling across from each other on the color wheel. (ie: Red is opposite of green, orange is opposite of blue, and yellow is opposite of violet.)