1. INTERFEROMETER

2. Albert Abraham Michelson
Michelson Interferometer
Albert Abraham Michelson
( )

3. Experimental set up

5. In Michelson interferometer
Radius of nth dark ring

6. Haidinger Fringe

8. Order of the fringe
Angular radius of the pth ring
Formation of both real and virtual fringes

9. Fringe collapse/emergence

10. 1. Measurement of wavelength of light

11. 2. Measurement of wavelength separation
of a doublet

12. Concordance

13. Discordance
= (q+1/2)

14. Measurement of the coherence length of a spectral line
Formation of straight white light fringes
Measurement of thickness of thin transparent flakes
Measurement of refractive index of gases
Standardization meter

15. Localization of Newton-Michelson rings

16. L = a R / U d = 2a – 2U /(R – 2U) Michelson interferometer: R L
Newton’s rings: a L

17. Newton’s Ring
U<<R & U>>d

18. Optical Coherence Tomography

19. Problem
The irradiance seen on the top surface of the wings of a Morpho
butterfly is due to the constructive interference of the light
reflected by thin terraces of transparent cuticle-like material. The
terraces extend outward, parallel to the wing. The electron
micrograph of the cross-section of the central structure of the
terrace is shown in (a) next slide. The terraces have index of
refraction n=1.53 and thickness Dt=63.5 nm; and they are
separated (by air) by Da=127 nm [see fig (b)]. The visible
light falls nearly normally on the terraces (in Fig. b the incident
angle is exaggerated for the understanding of the problem).
Show that the interference produced by r1 and r3 will produce
the visible color. What is the major color from the wing of the
Morpho butterfly?

21. Problem
In an experiment with MI, the successive readings for maximum
distinctness were found to be mm and mm
displacement of M2.
If the average wavelength for the two components of D lines be
5893 Å, deduce the difference in wavelength.