1. Notre Dame extended Research Community 1 Optics and Visible Light Michael Crocker Valerie Goss Rebecca Quardokus

2. 2 How do we see? target source detector …and often you’ll need a lens

3. 3 Magnifying Glass Magnification: 2-10x (Loupes 30x) One lens (Many Lenses and Prisms) Usually a biconvex lens - both sides are convex

4. 4 Focal Length Magnified Right Side Up Shrunk Upside Side Up Focal Length

5. 5 Chromatic Aberration  A kind of distortion (color)  Can be fixed to a certain extent  Imperfections also lead to distortions  Tilting the lens leads to another distortion

6. 6 Examples of Chromatic Aberration

7. 7 Activity: Assemble the Telescope! Arrrrgh!

8. 8 Telescope #1 Galilean Telescope Produces Upright Images

9. 9 Telescope #2 Wider Field of View

10. 10 Telescope #3 Allows for Larger Objectives (collects more light) Reflecting Telescope

11. 11 Microscope Light Source Stage and Sample Objective Lens Ocular Lens (Eyepiece)

12. 12 Telescope -> Microscope

13. 13 Magnification Objective Lenses 4x Magnification 10x Magnification 40x Magnification 100x Magnification 10x Magnification Total Magnification: 40x, 100x, 400x, 1000x Other techniques: Feature Size

14. 14 Focus Coarse and Fine Focus Knobs Larger Magnification Usually Means Shorter Depth of Field

15. 15 Example Image

16. 16 Digital Microscope

17. 17 Direct Viewing Light from the sample goes directly to your eye

18. 18 Indirect Viewing Light from the sample goes to a sensor, and an image is produced later on film, a screen, or as data in a computer

19. 19 Images and Rasterisation Computer Graphics: Any Magnification What about feature size?

20. 20 Digital Microscope Time!  Try looking at different objects  Fill out lab sheet about magnification

21. 21 Microscopy without Light  Other radiation  Special sensors  Machine intervention  Computer image processing  False Color

22. 22 Scale

23. 23 X-Rays and Gamma-Rays!

24. 24 Other Radiation – Radio Waves

25. 25 What Comes Next?  How to view things that do not emit light?  How to view things smaller than the wavelength of light?  What do we actually “see” when we use such techniques? http://www.mrs.org/s_mrs/doc.asp?CID=1803&DID=171434