Electronic whiteboards that use pressure-sensitive input are equivalent to a touch screen on a computer. When a teacher touches an option displayed on the screen with their finger or pen, the computer automatically handles the corresponding operation. In fact, this type of electronic whiteboard has two layers of pressure-sensitive film inside. When a point on the whiteboard surface is subjected to pressure, a short circuit is formed at that point between the two layers of film. The controller of the electronic whiteboard detects the coordinate value of the pressed point, which is sent to the computer via an interface.
Electromagnetic induction whiteboards use a pen that can emit electromagnetic waves, and receiving coil films are arranged horizontally and vertically on the LCD white board. When the pen approaches the receiving coil film, the coil will sense the electromagnetic wave emitted by the pen. The closer the pen is, the higher the induced electromotive force sensed by the coil film.
A scanning grid composed of infrared receiving and transmitting tubes densely arranged around the display area forms horizontal and vertical directions. When an object obstructs a pair of horizontal and vertical scanning lines in the grid, the position of X and Y coordinates can be determined by the position of the obstructed horizontal and vertical infrared lines.
Two ultrasonic wave receiving devices are placed on both sides of the screen at a fixed distance apart for positioning. The pen used for positioning is an ultrasonic wave transmitter. When the pen moves on the surface of the screen, the ultrasonic wave emitted by it is detected by the receiver along the screen surface. The distance between the pen and the two receivers can be calculated based on the time it takes for the ultrasonic wave to be received.
RF principle, sensors are installed in the whiteboard core to locate and receive specific frequency signals from the electromagnetic pen;
Our digital sigange displays have accurate positioning, high precision, high reliability and long service life, fast response speed, pressure sensitivity during writing, support for functions such as the right mouse button with the whiteboard pen, easy to operate on the computer.
Infrared principle, positioning is achieved by detecting objects that block the infrared light around the whiteboard;
Accurate positioning, relatively high precision, no need for a specialized pen, long service life, and fast response speed.
Resistance film technology, positioning is achieved through resistance value detection;
Relatively accurate positioning, no need for a specialized pen.