Diffraction is the bending of light waves as they pass from one medium to another. When light passes through an aperture or slit, it produces a diffraction pattern of alternating light and dark fringes. The size of the aperture determines the extent to which light bends and the ability of an optical instrument like a camera to resolve fine image details, with smaller apertures resulting in more diffraction and less resolution. Diffraction limits the resolving power of lenses and explains why images may appear blurred if the aperture is too large compared to the wavelength of light.

1. Diffraction of Light
Austen Corbitt and Lindsey
Stanfield

2. Objectives
❖Describe how light waves bend around
obstacles and produce bright and dark
fringes.
❖Describe how diffraction determines an
optical instrument’s ability to resolve
images.

3. Introduction
● In this presentation, we will be introducing:
✓Key Terms
✓How it works
✓How Light Bends Around Obstacles
✓Production of Dark and Light Fringes
✓ Resolving Images

4. Key Terms
•
•
•
•
Diffraction - a change in light wave direction
as they pass from one medium to another.
Aperture - a small slit in which light travels
Minima - the dark regions of the diffraction
pattern.
Prima Maxima - bright central region of the
diffraction pattern.

5. What is Diffraction?
•
•
Diffraction is when light passes through an
object because of the slits or holes in
it, causing it to produce a light on the other
side of that object.
There are many different ways diffraction
occurs: Light, sound, water, etc.

6. How Stuff Works
This is the maxima
This is the minima

7. How Light Bends Around an Object
❖Light bends around an object by
diffraction, obviously; but what does that
mean?
❖When an object interferes with the passage
of light, the waves will pass through a slit in
a objects. Then they will spread out in a
certain way on the other side of the object.

8. Examples
❖ Slit size equal to wavelength
wavelength
Slit size 5x the

9. Resolving Images
•
•
•
Most people didn’t know that diffraction is
also occurs in the resolution of images.
When a camera lens is used, diffraction
occurs when light passes through the
camera’s aperture, causing the picture to be
disoriented or unresolved.
The camera has a certain feature that
corrects the disoriented picture.

10. This picture is what is expected to
come out when a camera takes a
picture.
This picture is the result when the
resolution is disoriented because of
diffraction.

11. Cited Page
●
web.utk.edu. (n.d.). web.utk.edu. Retrieved October 28, 2013, from http://web.utk.edu/
●
Davidson, M. W. (1998, June 20). Molecular Expressions Microscopy Primer: Light and Color - Diffraction of
Light: Interactive Java Tutorial. Molecular Expressions Microscopy Primer: Light and Color - Diffraction of Light:
Interactive Java Tutorial. Retrieved October 28, 2013, from http://micro.magnet.fsu.edu/primer/java/diffra
●
McHugh, S. (n.d.). LENS DIFFRACTION & PHOTOGRAPHY. Diffraction Limited Photography: Pixel Size, Aperture
and Airy Disks. Retrieved October 28, 2013, from http://www.cambridgeincolour.com/tutorials/diffractionphotography.htm
●
Reichmann,, M., Raber, K., & Sanderson, C. (n.d.). Luminous-Landscape Copyright.Luminous-Landscape
Copyright. Retrieved October 26, 2013, from http://www.luminous-landscape.com/about/luminous_landscape