The image is inverted along the horizontal axis. When we stand in front of the mirror, our heads are still above and our feet are below. In fact, the mirror is neither upside down nor upside down, but upside down.

When you move in the direction I, the mirror image also moves in the direction I, indicating that the mirror image follows every movement in reality as long as it is parallel to the mirror plane.

When you move in the J direction, the mirror image moves in the opposite direction, which means that the mirror image is reversed along the axis perpendicular to the mirror surface. In short, when looking in the mirror, the left and right, up and down are actually not upside down, but "front" and "back".

Extended data:

Optical characteristics of mirrors:

First of all, reflection

The mirror's reflection of light obeys the law of reflection, and its reflection ability depends on the angle of incident light, the smoothness of the mirror and the properties of the plated metal film. The imaginary line perpendicular to the mirror is called the normal, and the angle between the incident light and the normal is equal to the angle between the reflected light and the normal.

The object in front of the plane mirror becomes an upright virtual image behind the mirror, and the distance from the virtual image to the mirror surface is equal to the distance from the object to the mirror surface. If you want to see my whole length in the mirror, the mirror must be at least half my length, because the incident angle is equal to the reflection angle. The reflective surface of concave mirror faces the center of curvature.

Second, focus.

After concave mirror reflection, the parallel rays converge to the focal point (f), which is located at 1/2 of the distance from the curvature center (c) to the mirror surface. If the cooker is placed in the focal position of concave mirror, it can be heated by sunlight and become a solar cooker. For example, a light source in a car lamp or a searchlight is placed in the focal position of concave mirror, so that light can reflect parallel light.

When an object is not in the center of curvature, it can be reflected as an inverted real image, such as reflecting telescope. The reflecting surface of convex mirror is back to the center of curvature, and the object forms a reduced upright image behind the mirror, which can reflect a wide range of reduced landscapes, such as car rearview mirrors.

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