Answer:
The wavelength is [tex]\lambda = 706nm[/tex]
Explanation:
From the question we are told that
The refractive index of the glass is [tex]n__{glass}} = 1.52[/tex]
The thickness of film is [tex]D = 127nm = 127*10^{-9}m[/tex]
The refractive index of film [tex]n__{film}} = 1.39[/tex]
The refractive index of air is [tex]n__{air}} = 1.00[/tex]
Generally the thickness of the film can be obtained mathematically from this expression
[tex]D = \frac{\lambda}{4 * n__{film}} }[/tex]
Where [tex]\lambda[/tex] is the wavelength
Making the wavelength the subject of the formula
[tex]\lambda = 4 * n__{film}} * D[/tex]
Substituting values
[tex]\lambda = 4 *1.39 * 127 *10^{-9}[/tex]
[tex]\lambda =7.06 *10^{-7}m = 706nm[/tex]
Answer:
[tex]\lambda = 706.12 nm[/tex]
Explanation:
The optical path length for the reflection of light = [tex]2 n_{film} t[/tex]
For destructive interference, [tex]2 n_{film} t = \frac{\lambda}{2}[/tex]
The thickness of the anti-reflective film = 127 nm
The largest wavelength of the reflected light, [tex]\lambda = 4n_{film} t[/tex]
[tex]\lambda = 4 * 1.39 *127 * 10^{-9}[/tex]
[tex]\lambda = 706.12 * 10^{-9} m\\\lambda = 706.12 nm[/tex]
