How do rainbows form after rain in summer?

In summer, after the rain, Chu Qing. In an instant, a rainbow appeared in the sky. It is a seven-color ribbon across the sky, red, orange, yellow, green, blue and purple, just like a colorful arch bridge flying across the sky. Why do colorful rainbows appear in the sky? After the rain, there are still many tiny water droplets suspended in the sky. When sunlight enters these small water droplets at a certain angle, it will produce two refractions and one total reflection, and then it will be emitted from the water droplets. So sunlight will be scattered into seven color bands, with purple inside and red outside. This is a rainbow. The angle between red light and incident light is about 42, and the angle between purple light and incident light is about 40. When the rainbow appears, sometimes there is another colored arc next to it-neon. The color arrangement of neon is just the opposite of rainbow, which is formed by the dispersion of sunlight after twice refraction and once total reflection in small water droplets. Because the light is reflected again in the water drops, the arrangement of colors is opposite to that of the rainbow, and the energy of light is lost, so the light band of neon lamp is not as bright as the rainbow. We can start to create a simulated rainbow. With your back to the sun and a mouthful of water in your mouth, spray the water into the air in a proper direction and you will see a beautiful artificial rainbow in the water droplets.