# I am in need of a formula. (visible wavelength, thin film)

1. Mar 31, 2008

### bobbo7410

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If anyone could help me out it would be greatly appreciated.

2nt = (m[+.5])$$\lambda$$

Last edited: Apr 1, 2008
2. Mar 31, 2008

### Mapes

What's the problem? You seem to have the right equation on hand.

3. Mar 31, 2008

### bobbo7410

o yea sorry, the further question was;

what would I use for m to achieve the minimum index? 1?

As well, would I use the [+.5] or not, meaning destructive vs constructive.

Those 2 were my detailed questions.

4. Mar 31, 2008

### bobbo7410

anyone?

5. Mar 31, 2008

### Snazzy

M would have to be the smallest possible integer without the right-hand-side being less than or equal to 0.