16.5 Lenses

Note :

(1) The ray diagrams are drawn conventionally, i.e. the incident ray penetrates the lens till central part of lens is undeviated. The effect of refraction then is in such a way that the ray parallel to axis will pass or appear to pass through the focus.

(2) The ray that is incident through the centre of lens is undeviated as it goes out of the lens.

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The image formations for various positions of objects are shown in Fig. 14 in case of bi-convex lens.
e.g. IP' is image of object OP
IQ' is image of object OQ etc.

For any position of object OP, the image IP formed is always between F & M (centre of lens), as illustrated in

Index

Light

16.1 Laws of Reflection at plane surfaces
16.2 Mirrors
16.3 Laws of Refraction at plane surfaces, Refractive Index and Critical Angle
16.4 Refraction at curved spherical surfaces and Lens maker’s formula
16.5 Lenses
16.6 Refraction in Prisms, Prism Formula
16.7 Dispersion of Light, Angular Dispersion and Dispersive Power
16.8 Optical Instruments and Magnifying Power

Chapter 17