Title: CONVEX LENS
1WELCOME
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2PRESENTATION ON CONVEX LENS
3 Types of Lenses
Lenses are used to focus light and form images.
There are two types of lenses, the concave and
the convex lens.
4ABOUT SPHERICAL LENS
- A transparent material bound by two surfaces, of
which one or both surfaces are Spherical is
called a spherical lens. - Spherical lenses are of two types -
- CONVEX or CONVERGING LENS
- CONCAVE or DIVERGING LENS
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5SOME TERMS USED IN LENS
- A line joining the centre of curvatures of two
spherical surfaces forming a lens is called
principal axis. - The point on the principal axis through which the
parallel rays of light to the principal axis
goes undeviated from its path is called the
optical centre. - A point on the principal axis of a lens where all
rays of light parallel to the principal axis
converge at a point passing through the lens is
called second principal focus of the lens - A point on the principal axis of a lens so that
the rays of light starting from this point after
passing through the lens become parallel to the
principal axis is called the first principal
focus of the lens. - The distance from the center of the lens to the
focal point is called the focal length.
6SOME TERMS USED IN LENS
- The distance between the principal focus and
optical centre of a - lens is known as focal length of the lens.
- A beam of light may fall on either side of a
lens. Therefore, a lens has two
principal foci. They are donated by F1 and
F2. Both principal foci are equidistant
from the optical centre. - The part of lens exposed to the incident light
is called aperture of the lens . -
- The distance from the center of the lens to the
focal point is called the focal length.
7WHAT IS CONVEX LENS ?
A Convex Lens is a type of spherical lens
that converges the ray of light coming from the
object. It is thick at the centre and thin at
the edges. There are three types of convex
lenses - PLANO- CONVEX LENS
CONCAVO CONVEX LENS
DOUBLE-CONVEX LENS
8IMAGE FORMATION BY CONVEX LENS
9SL. NO POSITION OF THE OBJECT POSITION OF THE IMAGE SIZE AND NATURE OF THE IMAGE
1. At infinity At Focus,F2 Real, Inverted, Highly Reduced
2. Beyond 2F1 Between F2 And 2F2 Real ,inverted, Diminished
3. At 2F1 At 2F2 Real, inverted, Equal in size
4. Between F1 and 2F1 Beyond 2F2 Real, inverted, Enlarged
5. At F1 At infinity Real, inverted, Highly magnified
6. Between F1 and C Beyond F1on the same side as the object Virtual, erect, Enlarged
10OBJECT AT INFINITY
11When object is at infinity , the image is
formed at focus (f2).
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F1
F2
O
NATURE OF THE IMAGE Real , inverted , highly
diminished .
12WHEN OBJECT IS BEYOND 2F1
13When the object is beyond 2f1, the image is
formed between F2 and 2 F2 .
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F2
2F1
F1
2F2
O
Nature of the image Real, inverted,
smaller in size than the object .
14WHEN OBJECT IS AT 2F1
15When the object is AT 2f1, the image is formed AT
2F2 .
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2F2
2F1
O
F2
F1
Nature of the image Real, inverted, equal
in size of the object.
16WHEN OBJECT IS BETWEEN 2F1 AND F1
17WHEN OBJECT IS BETWEEN 2F1 AND F1, THE IMAGE IS
FORMED BEYOND 2F2 .
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F2
2F2
2F1
F1
O
Nature of the image Real, inverted,
enlarged.
18WHEN THE OBJECT IS AT F1
19WHEN OBJECT IS AT F1, THE IMAGE IS FORMED AT
INFINITY.
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2F2
2F1
F2
F1
O
Nature of the image Real, inverted, highly
magnified.
20WHEN THE OBJECT IS BETWEEN F1 AND OPTICAL CENTRE
21When the object is between O an F1 , the image is
formed beyond F1 on the same side of the lens as
the object is.
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2F1
F1
F2
2F2
O
Nature of the image formed Virtual, erect,
magnified .
22APPLICATIONS OF CONVEX LENS
- Convex lens find a wide range of uses in our
daily life - It is used in astronomical telescopes to see
the heavenly objects - A convex lens of short focal lens is used in
microscopes to see biological specimens - It is also used in reading glasses
- It is used as a corrective lens for
hypermetropia - It also finds its use in cinematography
23- Designed By
- ABHISHEK SAHOO
- AKASH SAHA
- ASHUTOSH OJHA
- CHINMAYA SWAIN
- ABHINANDAN DAS
- ARYAMAN ABHISEKH
24THE END