Reflection of light (and other forms of electromagnetic radiation) occurs when the waves encounter a surface or other boundary that does not absorb the energy of the radiation and bounces the waves away from the surface.

A real image occurs when light rays actually intersect at the image, and is inverted, or upside down. A virtual image occurs when light rays do not actually meet at the image. Instead, you “see” the image because your eye projects light rays backward. A virtual image is right side up (upright).

The best surfaces for reflecting light are very smooth, such as a glass mirror or polished metal, although almost all surfaces will reflect light to some degree. Reflection of Light When light waves are incident on a smooth, flat surface, they reflect away from the surface at the same angle as they arrive.

Light rays from the object passing directly through the focal point are reflected back parallel to the principal axis. The convergence of the reflected rays creates an image. The distance from the focal point to the mirror’s surface is known as the focal distance (f).

The diverging rays from the object at the focal point emerge from the lens parallel to the optical axis, all the way to infinity. Because the rays never come together on that side of the lens, no image is formed. At the focal point, all of the parallel rays come together at a point.

In a concave mirror, the image is real if the distance of the object from the mirror is greater than the focal length and virtual if it is less than the focal length. If the object is at the focus the image is formed at infinity. In a convex mirror, the image is always virtual.

A real image can be viewed on a screen, a virtual image can not. Rays from both types can enter your eye, be refracted by your eye’s lens and form a real image on your retina as @CarlWitthoft points out. So it is not the case that a real image must be viewed on a screen. It can be viewed on a screen.

There are six possibilities of the position of object in the case of concave mirror.

• Object at infinity.
• Object between infinity and centre of curvature (C)
• Object at centre of curvature (C)
• Object between centre of curvature (C) and Principal focus (F)
• Object at Principal Focus (F)

Concave mirrors are used as searchlights, shaving mirrors, satellite dishes, and many more. These mirrors have the property to collimate and concentrate light rays. Concave mirrors in torches and headlights are used as reflectors.

Concave mirror: A concave mirror is a spherical mirror whose reflecting surface is on the inner side. It is also known as a converging mirror, as a parallel beam of light after reflection from a concave mirror converges at a point.

Convex mirrors are also popularly called as the fish eye mirror or diverging mirror. Its reflective surface bulges in the direction of the light source. A convex mirror has an ability to reflect all the light that falls on them in the outward direction.

Uses Of Convex Mirror

• Inside buildings.
• Vehicle mirrors.
• Magnifying glass.
• Security purposes.

Convex mirrors are used inside the buildings, They are also used in making lenses of sunglasses, They are used in the magnifying glass, They are used in securities and they are used in telescopes.

Uses Of Concave Mirror

• Shaving mirrors.
• Head mirrors.
• Ophthalmoscope.
• Astronomical telescopes.
• Headlights.
• Solar furnaces.

Convex Security Mirrors The reflective surface bulges outwards toward the light source which results in a distorted image but an expanded field of view. It is this wide-angle field of view which makes convex mirrors highly suitable for security applications in shops and retail premises.

• Inside buildings. You might have noticed that large office buildings, stores, hospitals, and other many other buildings have convex mirrors in the corners.
• Sunglasses. We might have used sunglasses many times.
• Vehicle mirrors.
• Magnifying glasses.
• For security purposes.
• Street light reflectors.

Convex mirrors are used in sunglasses, telescopes, roads with blind curves, etc. Concave Mirrors – These mirrors are also spherical, however, unlike convex mirrors, they curve inward like a spoon. Convex mirrors make an image look larger, and are typically found in make-up and shaving mirrors, etc.

Convex mirror is also called diverging mirror as it diverges the beam of light falling on it. It ia for this purpose that it is used in street lamps as it would diverge the light rays and hence spread the light so that visibility increases. It is used for different light rays falling on it to a single point.

Parabolic Concave mirrors with large apertures are used in search lights. In search light, we need an intense parallel beam of light for searching objects. When an object is placed at the focus of a concave mirror, the reflected rays are parallel to each other and also parallel to the principal axis.

Convex mirrors are used as reflectors in street lights because they are able to spread the light over a wide area.

Why Concave Mirrors are Used for Makeup Since concave mirrors focus light inward and magnify the object (aka your face), it allows you to better see your skin, eyes, and lips when applying makeup.

Concave mirrors are used in search lights and torches so that we have a more focused light beam which will not diverge out and hence help in searching.

A convex mirror or diverging mirror is a curved mirror in which the reflective surface bulges towards the light source. Convex mirrors reflect light outwards, therefore they are not used to focus light.