Hi,
To achieve this follow these steps;
1. Activate the expert mode in UI to see the tiny spanner symbol.
if you dont find that icon then enable configuration mode using 'Personalization'
2. Now click on the Spanner icon
3. Click on the Blue area
4. in the pop up select Contact Person filed and chose remove button
5. Save and Close
That's all
Cheers,
Vivek