YDSE-2 & thin film interference

Thin Film Interferance

When a light wave passes from a rarer medium to a denser medium, there will be a phase change of pi radians. This difference brings change in the conditions for constructive and destructive interference. This phenomena also reasons the fromation of interference pattern in thin films like, oily layer, soap film, etc., but has no reason on the shifting of fringes from the central portion outward. The shift is dependent on the refractive index of the material as per the relation, Delta y = (mu - 1) t Thin film interference happens with

Consider a case of thin film interference as shown.Thickness of film is equal to wavelength of light in mu_(2)

If wavelength 4500 Å and 6000 Å are found to be missing in the reflected spectrum in thin air film interference, the thickness of the film for normal incidence is nearly

Interference of light, Thin film interference and Introduction to YDSE

YDSE with white light||thin film interference||Newton's rings

Assertion (A) : The soap film in sun light is colourful Reason (R ) : Thin films produce interference of light

Lloyd's Mirror||Fresnel's Biprism||Thin film Interference||Newton’s Ring Experiment

In a regular YDSE, when thin film of refractive index mu is placed in front of the upper slit then it is observed that the intensity at the central point becomes half of the original intensity. It is also observed that the initial 3^(rd) maxima is now below the central point and the initial 4^(th) minima is above the central point. Now, a film of refractive index mu_(1) and thickness same as the above film. is put in the front of the lower slit also. It is observed that whole fringe pattern shifts by one fringe width. What is the value of mu_(1) ?

A plastic film with index of refraction 1.80 is put on the surface of a car window to increase the reflectivity and thereby to keep the interior of the car cooler. The widow glass gas index of refraction 1.60. What minimum thickness is required, if light of wavelength 600 nm in air reflected from the two sides of the film is to interfere constructively? (b) It is found to be difficult to manufacture and install coatings as thin as calculated in part (a). What is the next greatest thickness for which there will also be constructive interference?