Take a stainless steel spoon and look at your face from the concave and convex sides of the spoon. What did you find? UH huh?

When viewed from a concave surface, the face becomes smaller, and when viewed from a convex surface, the face becomes larger.

Reflection usually, when looking at a straight surface, the reflection will look back at you along the same straight line. You will see the right side up and the right side down. But when you look at the spoon, the situation is different.

The spoon is concave (inward), which is why it is upside down. Because it is concave, the light is reflected obliquely. The top of the spoon reflects downward, while the bottom reflects upward. The same is true for the left and right sides: the left reflects to the right, and the right reflects to the left. Because of this reflection, the contents at the bottom are displayed at the top, and vice versa.

Concave mirror principle

Concave mirror's principle is reflection imaging. The spoon is concave mirror, the convex lens is refractive imaging, and the concave mirror plays a condensing role, and the imaging varies according to the object distance. Mirror (including convex mirror) is an instrument that does not transmit light, but reflects it back. Light obeys the law of light reflection.

Imaging law: When the object distance is less than the focal length, it becomes a vertical magnified virtual image. The farther the object is from the mirror, the bigger the image. When the object distance is greater than 1 times and the focal length is less than 2 times, it becomes an inverted magnified real image; When the object distance is equal to 2 times the focal length, it becomes an inverted real image with equal size; When the object distance is more than 2 times the focal length, it becomes an inverted reduced real image; The farther the object is from the mirror, the smaller the image.