Difference between Concave and Convex mirror

Mirrors, often considered as simple everyday objects, play a crucial role in our lives. They enable us to see ourselves, our surroundings, and aid in various tasks. However, have you ever wondered how mirrors work? How do they manage to reflect an image so accurately? This article delves into the intriguing world of mirrors, explaining the underlying physics and shedding light on the difference between concave and convex mirror.

Understanding Reflection: The Basics

To comprehend how mirrors work, it’s essential to understand the concept of reflection. Reflection is the phenomenon where light waves bounce off a surface and travel in a different direction. Mirrors utilize this principle to create virtual images, enabling us to see objects that are not directly in our line of sight.

The Science Behind Mirrors

Mirrors are made from a sheet of glass with a reflective coating on the back. This reflective coating is typically made of a thin layer of aluminum or silver, which is responsible for the mirror’s ability to reflect light. When light waves strike the surface of the mirror, they interact with the atoms in the reflective coating. These atoms absorb the energy from the light waves and then emit new light waves. These emitted waves travel in the opposite direction to the incident light waves, resulting in the reflection that we observe.

Types of Mirrors: Concave and Convex

Mirrors can be broadly classified into two categories: concave and convex mirrors. These two types have distinct shapes and reflective properties that lead to different visual effects.

Difference between Concave and Convex Mirrors

  1. Shape:
    • Concave Mirror: A concave mirror curves inward, resembling a portion of the inner surface of a sphere.
    • Convex Mirror: A convex mirror, on the other hand, bulges outward.
  2. Reflection Properties:
    • Concave Mirror: Concave mirrors are known for their converging properties. When parallel light rays strike a concave mirror, they reflect and converge at a single point known as the focal point. This property makes concave mirrors useful in applications like reflecting telescopes and makeup mirrors.
    • Convex Mirror: Convex mirrors have diverging properties. Parallel light rays that hit a convex mirror will reflect and diverge as if they originated from a single point behind the mirror. This causes the image to appear smaller than it actually is and makes convex mirrors suitable for applications like side-view mirrors in vehicles.
  3. Image Formation:
    • Concave Mirror: Depending on the position of the object relative to the mirror, a concave mirror can create real or virtual images. Real images are formed when the object is placed beyond the focal point, while virtual images are formed when the object is placed between the mirror and the focal point.
    • Convex Mirror: Convex mirrors always produce virtual, diminished images regardless of the object’s position. These images are upright and smaller than the actual object.
  4. Focal Length:
    • Concave Mirror: The focal length of a concave mirror is positive, indicating that the focal point is in front of the mirror.
    • Convex Mirror: The focal length of a convex mirror is negative, indicating that the focal point is behind the mirror.

Applications of Concave and Convex Mirrors

Concave Mirror Applications:

  • Telescopes: Reflecting telescopes use concave mirrors to capture and focus light, enabling astronomers to observe distant celestial objects.
  • Makeup Mirrors: Concave mirrors are used in makeup mirrors to magnify the reflection of the face, making it easier to apply makeup with precision.
  • Headlights: Some headlights use concave mirrors to focus light beams and improve visibility on the road.

Convex Mirror Applications:

  • Safety Mirrors: Convex mirrors are commonly used as safety mirrors in places like parking lots and intersections. They provide a wider field of view, helping drivers see around corners and obstacles.
  • Decorative Mirrors: Convex mirrors are used as decorative pieces due to their unique distorted reflections that add an artistic touch to interior design.
  • Security Cameras: In some cases, convex mirrors are used in security cameras to achieve a wider field of view for surveillance purposes.


Mirrors are far more than just reflective surfaces; they are intricate instruments that leverage the principles of physics to create images and enable us to perceive our surroundings. Understanding the difference between concave mirror and convex mirror enriches our grasp of optics and expands our knowledge of the fascinating ways in which light interacts with matter. Whether it’s the captivating properties of concave mirrors or the practical applications of convex mirrors, these optical wonders continue to influence our lives in remarkable ways.