Wk6: Diffraction Abbreviations:
Saturday, November 7, 2020 1:35 PM b/w = between
w/ = with
INC = increase
• The wave nature of light (diffraction) poses a limit to the resolution that can be DEC = decrease
achieved.
○ Features of an object that are significantly smaller than the wavelength of light Central maxima; labeled n=0.
n=-1
n=-2
cannot be resolved.
○ Electron microscopes circumvent this limit. 100eV= 1.6*10^-17J
• Diffraction: bending of waves around sharp edges.
Dark spots are wavelengths that cancel each other out.
○ Occurs when waves strike objects w/ dimensions comparable to their wavelength.
○ Superposition (sum): sum of all parts of the waves that pass thru the opening.
○ Diffraction pattern: distribution of constructive waves and destructive waves;
depends on the wavelength of the waves and size/shape of the obstacle.
• Diffraction grating: consists of a single slit or many adjacent slits; laser strikes and
allows light waves to come through. Glass w/ holes in line pattern.
• The diffraction pattern produced by a grating is a series of alternating light and dark
spots (Fig. 6.1a).
• On either side of the central spot, at an angle θ1 from the incident direction, are the first
spots, followed by another pair of spots at θ2, etc.
○ The angles are related to the wavelength λ and the spacing between lines in the
grating d by the relation dsin𝜃𝑛=𝑛𝜆. -> dtheta = nλ
○ d: width of a single slit.
• The angle θ between the center of the bright spot and the first minimum (dark spot) is
given by sin𝜃 = 𝜆/𝑑.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller PrinceAlixD. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $5.49. You're not tied to anything after your purchase.
