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Images produced by lenses or mirrors are classified as real or virtual. Explain the difference between real and virtual images.

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Solution

Knowledge thin lenses

In optics, a real image is an image which is in the plane of convergence for the light rays that originate from a given object. If a screen is placed in the plane of a real image, the image will generally become visible on the screen (image produced on a detector in the rear of a camera and the image produced on an eyeball retina: the camera and eye focus light through an internal convex lens). A real image occurs where rays converge, whereas a virtual image occurs where rays only appear to converge.

Real images can be produced by concave mirrors and converging lenses, only if the object is placed further away from the mirror/lens than the focal point and this real image is inverted. As the object approaches the focal point the image approaches infinity, and when the object passes the focal point the image becomes virtual and is not inverted.

A virtual image is an image formed when the outgoing rays from a point on an object always diverge. The image appears to be located at the point of apparent divergence. Because the rays never really converge, a virtual image cannot be projected onto a screen. Virtual images are located by tracing the real rays that emerge from an optical device (lens, mirror, or some combination) backward to a perceived point of origin.