khaos89
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Hello, I am trying to understand thin film (in air) interference but I have a problem:
I know we have destructive interference when [itex]\delta=(2m+1)\pi[/itex].
Now i can try to calculate the thickness of the film to get it, so
since [itex]\delta =\frac{4nt\pi}{\lambda} - \pi[/itex] where t is the thickness,
I come to [itex]\delta=(2m+1)\pi=\frac{4nt\pi}{\lambda} - \pi[/itex]
that leads me to [itex]t=\frac{\lambda(m+1)}{2n}[/itex] instead of
[itex]t=\frac{m\lambda}{2n}[/itex]
(n is the refractive index and m is the integer parameter)
Where am I wrong?
I know we have destructive interference when [itex]\delta=(2m+1)\pi[/itex].
Now i can try to calculate the thickness of the film to get it, so
since [itex]\delta =\frac{4nt\pi}{\lambda} - \pi[/itex] where t is the thickness,
I come to [itex]\delta=(2m+1)\pi=\frac{4nt\pi}{\lambda} - \pi[/itex]
that leads me to [itex]t=\frac{\lambda(m+1)}{2n}[/itex] instead of
[itex]t=\frac{m\lambda}{2n}[/itex]
(n is the refractive index and m is the integer parameter)
Where am I wrong?