What is the name for two colors whose mixture produces white light, for example red and green?

When certain pairs of light frequencies combine, they don't just create a new color; they can astonishingly cancel each other out to produce pure white light. These special pairings are known as complementary colors. They represent opposite ends of the color spectrum, and their unique relationship is central to how we perceive and understand color itself.

It's a common misconception that red and green light mix to form white. In reality, red and green light combine to create yellow light. For light, true complementary pairs are those that, when added together, yield white. For instance, red light's complement is cyan (a mix of green and blue light), while green light finds its complement in magenta (a mix of red and blue light). Similarly, blue light is complemented by yellow light (a mix of red and green light). This phenomenon relates specifically to additive color mixing, where light is combined, rather than subtractive mixing, which applies to pigments.

Understanding these opposing yet harmonizing colors is fundamental to many fields. Artists and designers use complementary colors on a color wheel to create vibrant contrasts or visual balance. In science and technology, this principle is crucial for how our eyes perceive color, how televisions and computer screens display images using tiny red, green, and blue light pixels (Review), and even in photography to correct color casts. It's a fascinating interplay of light that reveals the hidden structure of color itself.