Od-4 Diffraction (Fresnel)
Published: Wednesday 15 March 2006 - Updated: Thursday 19 April 2007
Aim
To demonstrate the diffraction pattern of various objects subject to the Fresnel conditions (near field diffraction).
Apparatus
- Laser
- Optical bench
- Spatial filter
- Collimator
- ground glass screen
- T.V. camera and monitor
Diagrams
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Description
When the source or the image plane are too near the diffracting object for the curvature of the wavefronts to be negligible Fresnel diffraction prevails. The experimental setup above produces these conditions. Diffracting objects are placed at O.