1. Lenses

2. As light enters into a new medium it may bend due to refraction.
So on a flat piece of glass all light rays remain parallel
Snells Law states that the ratio of the sin of the angle of incidence to the sin of the angle of refraction is a constant for each material.

3. Lenses
Lenses are transparent spherical materials, usually glass, that refract light waves.

4. Lenses
Two basic lenses

5. Convex Lenses

6. Convex Lenses

7. Convex Lenses Object Beyond 2f
Image produced is real, inverted and same size
Object Beyond 2f
Image produced is real, inverted and larger in size
Image produced is real, inverted and smaller in size

8. Convex Lenses

9. Convex Lenses

10. Concave Lenses

11. Concave Lenses
A Concave (diverging) lens will produce a virtual image, no light actually focuses to the image position.

12. Concave Lenses