TFT-display: description, principle of operation

In modern household appliances such element as TFT-display is widely used. It is used in various types of devices: computer monitors, televisions, screens of cell phones, video cameras and cameras, as well as in many other devices. What is this technology, what are its advantages? In this article we will analyze what the TFT-display is, its advantages and disadvantages.

Thin-film transistor (TFT) in English means thin - film transistor. These elements are made of a thin film with a thickness of 0.1-0.01 microns. These transistors are controlled by a TFT-matrix, it is also called "active". To passive carry liquid crystal devices. Active TFT-display, in contrast to LCD technology, has a high speed, much higher clarity and contrast of the image and a much larger viewing angle. These devices do not have flickering of the screen, from which the eyes get tired. In active matrices, pixels generate light emission with a given color, so the TFT display is much brighter than passive liquid crystal matrices. All these advantages are due to the fact that the described technology has a higher refresh rate. This is due to the fact that each point of the display is controlled by a separate thin-film transistor. The number of such elements in TFT-technology is three times more than the number of pixels. Therefore, three colored cells correspond to one point: red, green and blue (RGB system). For example, consider the matrix: a TFT display (color) with a resolution of 1280x1024 pixels, respectively, the number of transistors in such a device will be 3840x1024.

The first liquid crystal matrix appeared in 1972. Since then, these technologies have significantly evolved and changed. However, it was not possible to eliminate all the shortcomings. For example, because of the large number of pixels, one can often find among them "broken", that is, idle ones. Such spoiled points are not subject to repair. It should be noted that on active matrices, "broken" pixels are less noticeable than on passive devices or dual-scan displays. Continuous development of TFT-technologies has allowed to significantly reduce the cost of production of such monitors, now "expensive exotics" has turned into a common phenomenon. An important factor in the wide distribution of active matrices in the industry has become ease of use. Nowadays, no one will be surprised by the touch TFT-display, and twenty years ago this was the limit of dreams. The expansion of the sensor monitors was preceded by the appearance of models capable of operating under harsh operating conditions. As a result, a TFT-display combining the visual information display means and a data input device (keyboard) have been developed. The efficiency of such a system is ensured by the serial interface controller. On the one hand, this device is connected to the monitor, and on the other hand to the serial port (COM1 - COM4). PIC controllers are used to control and decode signals from the sensor, as well as to suppress the "bounce". They are able to provide high speed, as well as accuracy of touch points.

In conclusion, TFT-technologies as a display and sensors surround us in everyday life, they are used in almost every household appliance.