Interactive whiteboards in detail

The surface

The surface of an interactive whiteboard is critical to its functionality and is a distinguishing factor between the different technologies used in the boards themselves. The interactive whiteboard captures the pen or user’s finger inputs and detects where the user is touching the board, this information is then used as input to the interactive whiteboard software.

There are 3 different technologies used for this purpose:

Resistive Membrane

The board surface incorporates a soft flexible vinyl or polyester-based plastic front surface and a rigid back board. Two layers of resistive material with a small gap between them create a touch-sensitive membrane, which is used to detect where a student or teacher touches the board. Applying pressure to the front surface (by using a pen or a finger) registers a contact point that is used as input to the interactive whiteboard software. The advantage of whiteboards based on resistive technology is that one does not require special pens to write on the board, a finger can be used just as well. One possible disadvantage is that as the surface of the board is soft it can be damaged by the use of ordinary markers, so the school needs to make users aware of this. Smart Interactive Whiteboards use resistive membranes.

Electro-Magnetic pick-up

These whiteboards are similar to traditional whiteboards in that they are rigid to the touch. The pens used with them emit a small magnetic field, which the board detects on pen impact or movement, and this information is then used as input to the interactive whiteboard software.  Promethean boards use this technology.

Infra-Red scanning

By attaching infra-red scanning devices to an existing whiteboard or flat surface it is possible to transform an ordinary whiteboard or surface to act as an interactive whiteboard. These scanning devices are light and portable and can be used with different types of standard whiteboards. Tracking of colour and patterns is based upon using special encoded pens, each of which has a uniquely encoded reflective collar that the board uses to identify its colour and position.