School of Physics Lecture Demonstration Manual

Oc-3 Zone Plates

Published: Wednesday 15 March 2006 - Updated: Monday 28 March 2011

Aim

To demonstrate interference using half period zone plates.

Apparatus

Diagrams

Click on pictures to enlarge.

Zone Plates Diagram

Description

The transmitter and receiver are positioned 2 metres either side of the zone plates. It is important to ensure that they are both aligned along the axis. The Zone plate has a focal point of 1 metre. The final position for the receiver is best found in the following manner; position the transmitter 2 metres from the zone plate, remove the two central zones and search with the receiver at the 2 metre mark for a minimum. When this has been found replace the outer zone and a distinct maximum should be observed if alignment has been satisfactory. The contribution of each zone on the wave field at the focus may now be demonstrated.

Safety notes

Electrical safety 

Maintenance 

top of page