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The Fabry-Perot interferometer

Makes shorter the incoming wavelength of the photon through interference.The interference between two mirrors amplifies the waves, hence, higher

energy photon on the other side, hence, shorter wavelength.AlsoShift will happen in the range of:

180 > > 0

.

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Lloyds mirror

Instead of two sources we have one and its reflection.Produces interference, but has a dark band where we would have expected

a bright one.

Reason: light suffered a 180 phase change upon reflection.Thats why we use polarising film on our cameras. It prevents any reflectionfrom getting into the apparatus.

Figure 1: The photo on the left almost completely eliminates reflections fromthe horizontal plane (water). Here we can see the increase in contrast of thewater lilies, but on the other hand we can observe that the sky is captured as itreally appears. The photo on the right does exactly the opposite, the reflectionsare left alone and the direct light from the sky is filtered as a result of which wecan see a bluer sky.

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Michelson Interferometer

The Michelson interferometer produces interference fringes by splitting a beamof monochromatic light so that one beam strikes a fixed mirror and the othera movable mirror. When the reflected beams are brought back together, aninterference pattern results.

An online tool to play with to understand what is happening there:http://www.gwoptics.org/processing/michelson01/michelson01.php

Compensator plate

The light passing through the mirror must also pass through an inclined com-pensator plate to compensate for the fact that the other ray passes through the

mirror glass three times instead of one. It makes sure that both beams travelthrough the same amount of glass, removing the dependence of the path lengthon wavelength.

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It depends on whether the semi-silvered block is silvered on the front or back.Its easier to stick it on the back, but that means the beam reflected initially

has to go through the block twice to be reflected, so the compensator is stuckin the path of the transmitted beam so it has to pass through the body of anequal block an extra two times as well.

Faraday effect

Happens when a plane of polarization is rotated as light passes through a ma-terial in the presence of a magnetic field.

Figure 2: = Bd

Intensity and irradiance

Intensity =power

solid angle=

cn0

2|E|2 Amplitude2

Intensity = Amplitude2 is only true if distance between slitsslit size

0 in the observa-tion of diffraction pattern.

Irradiance = powerunit area

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