# Single-sit vs. Double-slit vs. Diffraction grating

kamhogo

## Homework Statement

Briefly state one characteristic of single-slit /double-slit/diffraction grating interference pattern that allow you to clearly distinguish one from the others.

None

## The Attempt at a Solution

Single-slit:

Double-slit:
More intense, narrower central maximum that single-slit interference.
Less intense, broader (than grating), equally spaced maxima.

Diffraction grating

I don't think my answers are complete or correct or if they answer the question properly. I also have trouble understanding the reasons why those differences occur.

Homework Helper
Most are correct, I just don't understand what you mean by tall?

kamhogo
Most are correct, I just don't understand what you mean by tall?
Which aren't correct? By tall I mean than they are more elongated. The central maximum seems to keep the same height when you switch from single-slit/double-slit interference to diffraction grating interference but the secondary maxima get more elongated. The envelope is less of a dome and closer to a line...

Homework Helper
My reservation is on the tallness that you are talking about. Elongated in which direction? Is it in the direction perpendicular to the direction in which the fringes span?
The envelope is less of a dome and closer to a line...
The envelope actually corresponds to the intensity profile from a single slit, therefore if in those three cases the single slit size (length and height) can be assumed to be identical, then the envelope should be the same for all of them.

kamhogo
kamhogo
My reservation is on the tallness that you are talking about. Elongated in which direction? Is it in the direction perpendicular to the direction in which the fringes span?

The envelope actually corresponds to the intensity profile from a single slit, therefore if in those three cases the single slit size (length and height) can be assumed to be identical, then the envelope should be the same for all of them.
Thanks for the feedback. I understand it all a little better now.