A mirror is a reflective surface that is smooth and well-polished. Mirrors are classified into two types: spherical mirrors and plane mirrors. When an object is placed in front of a mirror, the light bounces off it, producing either the real picture or a virtual image. When the light beams connect, a true picture is formed. The apparent divergence of light beams from a point causes the formation of a virtual picture. A plane mirror always produces a virtual picture, but a spherical mirror produces both virtual and actual images.
Spherical Mirrors
Because spherical mirrors have a continuous curve and a fixed radius of curvature, they can create a virtual or actual picture. It is divided into two varieties based on the surface painting of the spherical mirror:
- Concave Mirror: Concave mirrors are made only when the exterior surface of a spherical mirror is polished.
- Convex mirrors are generated when the inside surface of a mirror is painted.
Concave Mirrors
Concave mirrors feature an inwardly curved reflecting surface. Concave mirrors are also referred to as convergent mirrors as they gather or concentrate the light that falls on them to a single focal point. Concave mirrors focus light rays and generate huge, clear pictures; therefore, their use is well-known and widespread in our daily life.
The examples of concave mirrors include shaving mirror, head mirror, microscope, dental mirror, etc.
Characteristics of Concave Mirror
- Before reflection, the concave mirror gathers and converges the incident light.
- When you position an object extremely close to the concave mirror, it creates a virtual and enlarged picture.
- When distance between the item and the concave mirror is increased, an actual image is generated, and the picture size decreases.
- Concave mirrors can generate huge, tiny, upright, or virtual pictures.
Applications
- Converging mirrors are most commonly utilized in shaving mirrors due to their reflecting and curved surfaces. When shaving, the concave mirror generates an expanded and erect picture of the face when it is held closer to the face.
- Concave mirrors used in ophthalmoscopes: These mirrors are used for therapy in optical devices such as ophthalmoscopes.
Convex Mirror
Convex mirror has an outward curve in the center that permits light rays from an object to collapse on it. It is also known as a diverging mirror because of its propensity to diverge the rays that fall on its surface after reflection. This is because when parallel beams reach the shiny surface of this mirror, the rays diverge.
The examples of Convex Mirrors include side-view mirrors of vehicles, sunglasses, etc.
Characteristics of Convex Mirror
- As they scatter light outwards, convex mirrors are often described as divergent mirrors.
- They do not concentrate light on a single spot.
- The convex mirror always generates virtual, reduced, and erect pictures regardless of the distance between the item and the mirror.
Applications
- Convex mirrors used within buildings: convex mirrors are used inside large workplaces, shops, and hospitals to allow people to look around the corner and avoid colliding.
- Convex mirrors are often utilized as rear-view mirrors in automobiles and vehicles because they can diverge light beams and create virtual pictures.
Difference between Convex Mirror and Concave Mirror
- A concave is a type of mirror with an inward curved reflecting surface, on the other side a convex is a type of mirror with an outwardly bulging reflecting plane.
- A convex mirror has a divergent n and is thus called as a diverging mirror,
- Concave mirror has a convergent category and is called a converging mirror. In contrast,
- Concave mirrors’ focus and C.o.C(center of curvature) are located in front of the mirror. In contrast, the convex mirror’s focus and C.o.C (center of curvature) are spotted on the rear of the mirror.
- Because the concave mirror’s focus is on the front side, its focal length is positive, but the convex mirror’s focus is on the backside; therefore, its focal length is negative.
- Image projection on a concave mirror can be made on a screen; however, projection of image on a convex mirror cannot be made.
- The magnification of a concave mirror can be greater than, equal to, or less than one. The value of being’ in a convex mirror, on the other hand, is less than one.
- A convex mirror generates an image that is often smaller than the actual picture, and hence the image created seems to be shrunk. On the other hand, a concave mirror generates an image which is often bigger than the real picture, resulting in a magnified image.
Conclusion
Concave mirrors provide an image that seems larger than the real size of the item. They are thus mostly employed as cosmetics mirrors, telescopes, automotive headlights, torches, dental clinic mirrors, etc. Convex mirrors, on the other hand, generate decreased images and are mostly utilized in rearview mirrors, sunglasses, etc.