Fighting disease with lasers, light

September 8, 2010

By hammersmith

[Source: UA News] – Have you ever wondered why, or rather how, flowers have such bright colors? As you might imagine, some fairly complex physics and chemistry lie behind the vibrant reds, yellows, blues and greens that shine when sunlight meets leaf or flower.

Sunlight includes all the rainbow colors of the visible light spectrum, plus some invisible ones such as ultraviolet and infrared. Desert lavender, for instance, is blue because pigments in its flowers absorb yellow light and reflect other colors, which appear blue in combination.

But what, exactly, happens in that minuscule fraction of a second after a photon of sunlight strikes an atom in a plant pigment? In fact, what happens when a photon of light hits any atom in any substance, including the human body?

For more information: Fighting Disease With Lasers, Light