A visualiser, also known as a document camera, is a camera mounted on a stand that connects to a projector. In many ways a visualiser is a ‘modern’ combination of a camera, a microscope and the overhead projector. Documents or objects can be placed under the camera and the image projected onto a screen/whiteboard. It is ideal for showing 3D objects, sharing books, children’s work, photographs and pages.
For more information, see the following links

What is a Visualiser?  (PDF)
An article by Anne White of NCTE, from In Touch magazine, January-February 2011, with some useful ideas for using a visualiser in the classroom.

NCTE ICT Advice Sheet: Visualisers (PDF)

What is a Visualiser? from NCTE on Vimeo.

Visualiser New Book from NCTE on Vimeo.

Using the Visualiser and the tablet Laptop (As Gaeilge) from NCTE on Vimeo.