1. Young’s double slit experiment
Division of Wavefront

2. Michelson Interferometer
Division of Amplitude

3. Effective Arrangement

4. Fringe Conditions
Dark

5. Circular Fringes

6. Central Dark Fringe

7. Fringe Spacing

8. Increasing d

9. Measuring Wavelength

10. Close Spectral Lines
Example Sodium
589.0 nm and nm

11. Concordance

12. Discordance

13. Michelson Interferometer
Observer Year Arm length (in m)
Michelson
1881
1.2
Michelson & Morley
11.0
1887
Miller
32.0
1929
Michelson et al
25.9
21.0
Joos
1930

14. LIGO

15. Ligo Arm Length 4 km Hanford and Livingston in USA
Caltech, MIT and other US Universities

16. Gravitational Waves

17. Ligo