Embedded touch technology in-cell touch TFT Display Module

Embedded touch technology, operational classification would be divided into optical (Photo Sensor), a press-contact and non-pressure touch, another part can be subdivided capacitor induction or resistance-type sensor. previously mentioned the touch control circuit should also be reluctant to be regarded as kinds of integrated touch panel technology (also known as on cell touch) on the display surface, this externally attached to the display panel out-of-touch panel design, is the most commonly used one, iPhone 5 will really continue to use it?
Generally, the optical embedded touch technology (Photo Sensor) from the reflected light of the finger can be detected finger shadows or backlit to Analyzing touch or not, can also change photocurrent generation optical document irradiated Photo Sensor later determine the touch or not to use the benefits of optical embedded touch technology without force and can do multi-touch, but the problem is when the environment light irradiation surface of the touch screen is possible misuse the touch behavior judgment, and Photo Sensor one-on-one chimeric pixels (Pixel), natural the Pixel opening rate have an impact on fact, and indeed manufacturers to modify the design, the use of more than one pixel with a photo sensor concept, but the problem lies is how the user wants to touch resolution!
Simple to say, while reducing the Photo Sensor number, touch resolution of the apparatus will decrease, more intuitive user point of view, in some cases in a screen, draw an arc is not a smooth curve, You can accept it? Although the operation had no need to use one-to-one chimeric Photo Sensor with Pixel architecture, but the demand for useful fine pen you have to use the fingers.192x64 lcd

In addition, in the press-contact sensor, although it is divided into two kinds of resistive and capacitive, but the the pressure touch users need to use a little bit of force to press the surface of the touch screen, in fact, other than in the manufacturing part of the also involve the difficulty to process further, the resistance is the use of a user pressing the touch screen surface caused by the contact of the upper and lower substrates of the display electrode, sensing Vcom stars pressure changes to determine the coordinates of the contact position.
Capacitive you do not need to contact through the upper and lower substrate electrode, using only the user presses on the surface of the touch screen of the monitor on the lower glass spacing reduced, resulting in a change in capacitance (Cell Gap), transformation than the fixed reference capacitor voltage signal to determine whether the contact, but whether it is pressure touch resistive or voltage electric shock capacitive the pressure touch sensor is a single touch, which are used more than just a gesture friends should be a great pity?
Finally, to introduce of Capacitive do monitor the inner layer (in cell) non-pressure-touch touch the (embedded non-the pressure electric shock capacitive touch), although many people say that the network embedded non-pressure electric shock capacitive touch eliminating the need to protect the glass, but the views of the younger brother to look at the block diagram below, to remove the touch protective glass is not is not.240x128 lcd