Why do people see the color of tricolor gyro when it rotates at high speed?

Because the color of the reflected light of the object is the color of the object, when the gyro rotates at high speed, the reflected light of the three-color pigment enters people's eyes. Because the time difference of incident light of various colors is very small (high-speed rotation), people's eyes see the mixed effect of three-color light, because they are separated visually.

The reflected light and the incident light are on the same plane as the normal; Reflected light and incident light are separated on both sides of the normal; The reflection angle is equal to the incident angle? . It can be summarized as: "Three lines * * * plane, two lines are separated, and two angles are equal". Light is reversible. In the phenomenon of light reflection, the optical paths are equal.

Application of reflected light

In the field of photography, reflected light means that the light is not directly emitted by the light source and shines on the scene, but is reflected by the props once and then shines on the subject. Usually, the props used to reflect light are not pure planes, but reflectors treated by special techniques.

In this way, the reflected light can obtain the irradiation effect of scattered light, that is, softening. Generally speaking, reflected light is weaker than direct light but stronger than natural scattered light, which can make the light receiving surface of the subject softer. The reflection light is most commonly used in portrait photography under natural light. Let the protagonist turn his back to the light source, and then use the reflector to reflect the light to the character's face. In addition, reflected light is often used when shooting some commodities or still life.

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