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Table summarises the differences between a convex lens and a concave

Science lens. Table: Differences between Convex Lens and Concave Lens
Bytes

Testimony
The lenses in cameras, Convex Lens Concave Lens
microscopes, and even It is thicker in the middle and tapering It is thicker at the edges and thinner
our eyes work on the
at the edges. in the middle.
same principle. A convex
lens bends light rays It converges the rays of light. It diverges the rays of light.
inward to form a real
image - just like the lens It generally forms real and inverted It always forms virtual and erect
in your eye focuses light image. However, it forms a virtual, image, smaller in size than the object.
onto the re na. erect and magnified image when the
Meanwhile, concave object is placed very close to the lens.
lenses spread light
outward and are o en
used in spectacles for Uses of Lenses: Lenses are used as magnifying glass in camera, spectacles,
people who are short-
sighted, helping them see microscopes and telescopes. Lenses improve the quality of images that are
distant objects clearly. viewed through them.

Know Your Scientist
Joseph von Fraunhofer (1787-1826), a German optician and physicist, made groundbreaking contributions to
the study of lenses and optics. He developed high-quality optical glass and precise lenses used in early
telescopes and spectrometers. His discovery of Fraunhofer lines in the solar spectrum laid the foundation for
modern spectroscopy, helping scientists understand the composition of stars and planets.

Grasp-Up

Reflec on of light: The phenomenon of bouncing back of light from the surface of an objet.
Normal: A line perpendicular to the surface of the mirror at the point of incidence.
Incident ray: The ray of light coming from an object that falls on the surface of the mirror.
Reflected ray: The ray of light that gets reflected from the mirror.
Angle of incidence: The angle formed by the incident ray with the normal.
Angle of reflec on: The angle formed between the reflected ray and the normal.

Points to Reflect

• There are two laws of reflection. Law I states that the incident ray, the reflected ray and the normal all lie in
the same plane. Law II states that angle of incidence is equal to the angle of reflection.
• The image formed by a plane mirror is virtual, erect, of same size as the object, formed behind the mirror, is
formed as far behind the mirror as the object is in front of it and is laterally inverted.
• Reflection is categorised into two - regular reflection and diffused reflection.
• The image found by a convex lens can be enlarged, dininshed or of the same size as the object and it may be
erect or invested, depending upon the distance of the object from the mirror.
• A convex lens converges the light beams while a concave lens diverges it.

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