1. Image formation with lenses

2. Operating Principle Lenses use the principle of refraction to change the shape of a light beam. -Bending of light – Why?

3. Operating Principle Lenses use the principle of refraction to change the shape of a light beam. - Refractive index

4. Operating Principle Lenses use the principle of refraction to change the shape of a light beam. - Refractive index

5. Operating Principle Lenses use the principle of refraction to change the shape of a light beam. - Refractive index

6. Operating Principle Lenses use the principle of refraction to change the shape of a light beam. - Refractive index

7. Operating Principle

8. Lenses use the principle of refraction to change the shape of a light beam. - Refractive index- Curvature

9. Operating Principle Wavefront picture

10. Operating Principle Wave picture

11. Operating Principle Lenses use the principle of refraction to change the shape of a light beam. - Refractive index- Curvature

12. Operating Principle Lenses use the principle of refraction to change the shape of a light beam. - Refractive index- Curvature

13. Operating Principle Lenses use the principle of refraction to change the shape of a light beam. - Refractive index- Curvature

14. Operating Principle Consider lens thickness negligible:

15. Types of lenses Convex lens:

16. Types of lenses Concave lens:

17. Types of lenses Positive meniscus lens:

18. Types of lenses Negative meniscus lens:

19. Fresnel lenses

20. Image formation Ray tracing rules: In: parallel to the optical axis – Out: through back focal point In: through the centre of lens – Out: travel unchanged In: through the focal point – Out: parallel to the optical axis

21. Image formation Image condition: “all” light rays emitted by one point in the sample meet in a defined point behind the lens -> imaging plane

22. Image formation The visualized object: Each point reflects (emits) light in all directions => multitude of point light sources

23. Image formation Ray tracing rules:

24. Image formation Ray tracing rules: Image distance (S2) in focal dist. Object distance S1 in focal dist. Positive lenses Negative lenses

25. Lens systems Compound lenses: No distance between them (z=0)

26. Lens systems Compound lenses: when z > fo+fi - Two converging lenses in series -> upright, scaled image

27. Lens systems Infinite conjugate system: if object in the focal point -> the distance between the lenses is not relevant (can be infinite)

28. Lens systems Infinite conjugate system: if object in the focal point -> the distance between the lenses is not relevant (can be infinite)

29. Lens systems Beam expanders: Collimated light source

30. Lens systems Beam expanders: Collimated light source – if, the light beam is expanded.