How Interactive whiteboards work?
Posted by smartboards on September 19, 2006
An interactive whiteboard solution typically consists of four components:
- A computer, PC/Laptop etc
- A projector
- A display panel
- An appropriate software
The computer is connected to the projector and electronic whiteboard. The projector displays the computer screen image onto the electronic board. Action on the surface of the display panel is communicated with the computer over a cable or wireless connection and interpreted via the installed software. Display panels can be either front or back projection, i.e. the projector can be placed either in front of board or at the rear.
Additional components and accessories are available for some systems including hand held key pads for collecting individual responses and interactive white board tablets: in fact a small personal version of the larger board.
Some systems employ plasma screens instead of a projector, but they are very expensive and not considered further here.
There are three different kinds of interactive whiteboards technology:
Touch-sensitive
These electronic whiteboards have a soft flexible surface like vinyl, consisting of two pieces of resistive layers with a small gap between them to produce a touch-sensitive membrane. They can be drawn on using fingers or a special stylus that can represent pens of different colors via software selection. Movement is tracked by detecting the pressure of the stylus object on the surface. The coordinates on the panel correspond to the area on the corresponding connected computer’s monitor.
Electro-Magnetic
These electronic whiteboards are similar to traditional whiteboards in that they have a hard surface and can be drawn on with normal pens. To work interactively they require special digitized pen, battery driven pens, that emit a small magnetic field that is detected either by the frame of the whiteboard. The whiteboard panel is digitized by a grid of fine wires embedded beneath the surface of the board. The signal from the digital pen also communicates location to the commuter even when it is at a distance from the actual surface of the digitized grid. This is the z-axis or the proximity signal. In the case of electromagnetic signal, the precision of input is controlled by the dispersion or width of the signal emitted from the electronic pen, and the density of the lines in the underlying digitized grid.
Laser sensor
These interactive whiteboards have a hard writing surface with infrared laser sensors mounted in the top corners of the board that detect pen movement. To work interactively they require special felt pens, each of which has a uniquely encoded reflective collar that the lasers use to identify its color and position.
