Physics > Wave Optics > 1.0 Introduction
Wave Optics
1.0 Introduction
1.1 Wavefronts
1.2 Huygens Principle
1.3 Interference of light
1.4 Intensity distribution
1.5 Phase difference
2.0 Young's double slit experiment
3.0 Diffraction of light
4.0 Polarisation
1.3 Interference of light
1.2 Huygens Principle
1.3 Interference of light
1.4 Intensity distribution
1.5 Phase difference
It is the phenomenon of redistribution of energy on accounts of superposition of light waves from coherent sources.
Interference pattern produce points of maximum and minimum intensity.
Points where resultant intensity is maximum then the interference is said to be constructive and at the points of destructive interference resultant intensity is minimum.
1.3.1 Conditions of interference
To produce a stable interference pattern the individual waves must be coherent.
1. Coherent sources: The source of light, which emits continuous light waves of the same wavelength, same frequency and in same phase or having a constant phase difference are known as coherent sources.
Two independent sources of light cannot be coherent.
2. Equality of amplitudes: The amplitudes of two interfering waves should be equal or approximately equal.
Maximum contrast is obtained when $A_1=A_2$, because then minimum intensity will be zero.
3. The two sources must lie very close to each other and the two sources should be very narrow.
