Wave Optics

In Young's double slit experiment, the wavelength of light used is '\(\lambda\)'. The intensity at a point is '\(\mathrm{I}\)' where path difference is \(\left(\frac{\lambda}{4}\right)\). If \(I_0\) denotes the maximum intensity, then the ratio \(\left(\frac{\mathrm{I}}{\mathrm{I}_0}\right)\) is

\(\left(\sin \frac{\pi}{4}=\cos \frac{\pi}{4}=\frac{1}{\sqrt{2}}\right)\)