What is the minimum thickness of a thin film | vedclass

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(A) The condition for constructive interference in reflected light from a thin film is given by $2 \mu t = (2n + 1) \frac{\lambda}{2}$, where $n = 0,

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(A) The condition for constructive interference in reflected light from a thin film is given by $2 \mu t = (2n + 1) \frac{\lambda}{2}$, where $n = 0, 1, 2, \dots$ and $\mu$ is the refractive index, $t$ is the thickness, and $\lambda$ is the wavelength.For the minimum thickness, we take $n = 0$.Substituting the values: $2 \mu t = \frac{\lambda}{2}$.Rearranging for $t$: $t = \frac{\lambda}{4 \mu}$.Given $\lambda = 600 \, nm$ and $\mu = 1.5$, we get $t = \frac{600}{4 	imes 1.5} = \frac{600}{6} = 100 \, nm$.

What is the minimum thickness of a thin film required for constructive interference in the reflected light from it (in $ nm$)? Given, the refractive index of the film $= 1.5$, wavelength of the light incident on the film $= 600 \, nm$.

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