A real image is formed when the light rays actually converge at a specific point after passing through a lens or reflecting off a mirror. It can be projected onto a screen and is always inverted. Real images can be further classified into two types: magnified and diminished.


A magnified real image is formed when the object is placed very close to the lens or mirror. The size of the image is larger than the size of the object. Examples include:
- A magnifying glass: When an object is placed near a magnifying glass, a magnified real image is formed on the opposite side of the lens.
- Overhead projector: The overhead projector projects an enlarged image of the transparency onto a screen.


A diminished real image is formed when the object is placed beyond the focal point of the lens or mirror. The size of the image is smaller than the size of the object. Examples include:
- Slide projector: The slide projector forms a diminished real image of the slide onto a screen.
- Camera: The camera forms a diminished real image on the film or image sensor.


A virtual image is formed when the light rays appear to diverge from a specific point after passing through a lens or reflecting off a mirror. It cannot be projected onto a screen and is always upright. Virtual images are formed when the object is placed closer to the lens or mirror than the focal point.


- Plane mirror: When an object is placed in front of a plane mirror, a virtual image is formed behind the mirror. The image is the same size as the object and appears to be located behind the mirror.
- Convex mirror: A convex mirror always forms a virtual image. The image is smaller than the object and appears to be located behind the mirror.


- Concave lens: When an object is placed in front of a concave lens, a virtual image is formed on the same side as the object. The image is smaller than the object and appears to be located behind the lens.
- Convex lens: A convex lens can form both real and virtual images. When the object is placed closer to the lens than the focal point, a virtual image is formed on the opposite side. The image can be magnified or diminished depending on the distance of the object from the lens.

In summary, real images are formed by the actual convergence of light rays and can be projected onto a screen. They can be magnified or diminished. On the other hand, virtual images are formed by the apparent divergence of light rays and cannot be projected. They are always upright and can be formed in mirrors and lenses.