Real & Virtual Images (Cambridge International IGCSE Physics)

Real images & virtual images

Spec point — 3.2.7 · Describe the characteristics of an image using the terms enlarged/same size/diminished, upright/inverted and real/virtual

• Images produced by lenses can be one of two types:

  • a real image
  • a virtual image

• Images can be described compared to their object as:

  • enlarged/same size/diminished
  • upright/inverted
  • real/virtual

Real images

• A real image is defined as:

An image that is formed when the light rays from an object converge and meet each other and can be projected onto a screen

• A real image is one produced by the convergence of light towards a focus

• Real images are always inverted

• Real images can be projected onto pieces of paper or screens

  • An example of a real image is the image formed on a cinema screen

A real image

A real image can be projected onto a screen

Virtual images

• A virtual image is defined as:

An image that is formed when the light rays from an object do not meet but appear to meet behind the lens and cannot be projected onto a screen

• A virtual image is formed by the divergence of light away from a point

• Virtual images are always upright

• Virtual images cannot be projected onto a piece of paper or a screen

  • An example of a virtual image is a person's reflection in a mirror

A virtual image

A reflection in a mirror is an example of a virtual image