Blackboard It is a concept that can be used in various ways. One of its most common meanings is associated with element about which you can draw or write with a chalk or a marker that can be erased easily. The term, in this case, is synonymous with blackboard .
For example: “Could you move a little to the side, please? I just cover the board and I can't read what the teacher writes ”, "The coach wrote on the board the names of the players that will integrate the starting lineup", “When I was little, I was entertaining by drawing on a blackboard that my aunt had given me”.
Typically, the boards are rectangular and have the painted surface of black or of green . These elements are very frequent in the field of education , as teachers use them to make notes, announce activities, etc.
It is important to note that these objects are known as blackboards since, in ancient times, they used to be manufactured with the rock which is called blackboard . This stone was polished and smoothed so that it could be written with plaster or other material on its surface.
Slate, like rock, is formed from clay and, in certain cases, igneous stones. Its most salient feature is that it is divided into plates or lamellae Of small thickness.
Today there are Digital boards , which are tablets connected to a computer (computer). The user can interact with the board, writing with special pencils or even by hand. Among its most common applications is education (teachers and students can interact comfortably with a giant screen), research (many people can contribute their ideas during meetings using various tools) and presentations (facilitate the presentation of concepts thanks to the possibility of manipulating the screen content with great precision and flexibility).
The blackboard digital Interactive can use one of the following technologies, among others:
* electromagnetic : a special pointer must be used in combination with a mesh that covers the total surface of the screen , which serves to detect the signal sent by the first and then pass it to the computer. To get a rough idea of the reliability of this type of board, the accuracy of its technology is 77 times higher to that of a touch screen;
* infrared : the pencil emits an infrared signal that can be composed of one or two points, and this is collected and analyzed by a camera to calculate its position and convert it to Cartesian information, which is then used to position the pointer onscreen. It is worth mentioning that this technology does not require a screen but takes advantage of any surface on which it is projected, which is why it is usually called interactive projection;
* resistive : The screen of the board is composed of two layers, one of which (the outside) is deformed when pressed. Thanks to such flexibility, the inner layer can detect the Contact and calculate the location where it took place. Among the advantages of this technology is the possibility of interacting with the hands or with any type of pencil, as well as the fact that the screen is more protected from scratches and potential damages due to liquid spillage, for example;
* optics : the board has light bars on its perimeter, whose issue It is controlled by two cameras located one on each side. When the user touches the screen, an inevitable interference occurs in said light projection, whereby the system proceeds to detect its location. As with resistive screens, it is not necessary to use a special type of pointer to interact with an optical board.