Surface capacitive and projected capacitive oled modules screen technology

Surface capacitive technology (Surface Capacitive), i.e. its architecture is relatively simple, with a layer of ITO glass body has at least four peripheral electrodes, a voltage is provided in the corners of the glass, the glass surface to form a uniform electric field, when the user touch press operation, the controller will be able to take advantage of changes in the human finger and the electric field generated by the reaction of the electrostatic detected touch position coordinates. This type of architecture determines the surface capacitive technology multi-touch functionality can not be achieved, because it uses a homogeneous sensitive layer, and this sensitive layer only on the touch screen to any position sensing signal converging to a The larger signal, homogeneous layer destruction of too much information that can not be sensitive to multi-touch. In addition, surface capacitive touch screen miniaturization difficult, difficult to apply to the cell phone screen, mostly used for large-size field. OLED Display Module
The projected capacitance (Projective Capacitive) technology, multi-touch hope for. Its basic principle is based on capacitive sensing, but compared to the surface capacitive touch screen, the projected capacitive touch screen multi-layer ITO layer to form a matrix distribution, the X-axis, Y-axis cross-distribution as the capacitance matrix, When a finger touches the screen, the X, Y axis scan to detect a change in capacitance of the touch position, and then calculate the finger lies. Based on this framework, projected capacitive multi-touch operation can be done. (Officially announced Sony Ericsson X10 version will support multi-touch, result of the upgrade, multi-touch is gone.)
Projected capacitive touch technology, there are two: one is the self-capacitance type (self Capacitance, also known as absolutecapacitance) to another for mutual capacitance type (mutual Capacitance, also known as transcapacitance). The self-capacitance type touch and generate capacitive coupling between the electrodes, and the amount of the change in capacitance of the measuring electrode is identified by touch occurs; mutual capacitance type occurs when the touch, capacitive coupling phenomenon will be generated in the neighboring layer 2 between the electrodes.color lcd display module
According to these two principles can design different the projected capacitive framework is different, different architectures can do multi-touch features. In fact, multi-touch can be subdivided into two types: one is The the gesture recognition tracking and interactive (Gestureinteraction), that is only detect, distinguish multi-touch behavior, such as zoom, drag, rotate ... achieve axis interlaced (Axis intersect); Another is to identify the individual position of multi-touch, this feature requires a complex contact positioning possible (All point Addressable; APA) technology can be reached.