Does the virtual image have a size?

A miniature virtual image is being erected.

The focal length of the objective lens is larger, and the focal length of the eyepiece is smaller. The front focus of the eyepiece coincides with the back focus of the objective lens, and the distant object is inverted and reduced by the objective lens, which is located outside (close to) the back focus of the objective lens, and then the eyepiece is enlarged.

Just because the final virtual image is larger than the real image formed by the objective lens does not mean that the virtual image is larger than the original object. In fact, the final image formed by the telescope is smaller than the original object, but the distant object is moved closer and the viewing angle is increased.

An image in which light is reflected by concave mirror or refracted by a convex lens and fused together. It can not only appear on the screen, but also make the photographic film sensitive, so it must be used for photography or film projection. Only when the light source is out of the main focus can a real image be generated.

Extended data:

Virtual images can be seen directly with the eyes, but cannot be accepted with the light screen; The real image can be accepted by the light screen, or it can be viewed directly with the eyes. When people look at the virtual image, light still enters their eyes, but the light does not come from the virtual image, but is reflected or refracted by optical elements. It's just that people have the experience of "light travels in a straight line" and think it is emitted from a virtual image.

Virtual images can be formed by reflection or refraction, for example, a plane mirror forms an equal virtual image and a convex lens forms an enlarged virtual image.

This is because the light emitted by the light source is everywhere, and some light enters people's eyes after being reflected by a flat mirror, causing optical illusion, and we feel as if the light is emitted from another place (S'). S is the image of S in the plane mirror.

If you use a glass plate as a flat mirror, light a candle on the front; At this time, there is no lighted candle behind the flat mirror, but we see that there seems to be a candle behind the flat mirror.

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