Question

What is angular fringe width?

Answer 1

1. When we see an interference pattern due to double-slit interference say, we observe alternate bright and dark fringes of the same sizes.
2. The width of these fringes is called fringe width.
3. Angular fringe width is the ratio of fringe width to the distance between source and screen.
4. Young’s double-slit experiment uses two coherent sources of light placed at a small distance. It helps to find angular fringe.
5. Angular fringe width mathematical equation:
   $\mathrm{\theta }=\frac{\mathrm{n\lambda }}{\mathrm{d}}$
   Where $\mathrm{\theta }$represents angular fringe width, $\mathrm{\lambda }$ represents wavelength, $\mathrm{n}$represents a number of bright fringes, $\mathrm{d}$ be the distance between two slits.