Capacitive touch Panel (CTP)

Capacitive and resistive touch panel are the two main types of touchscreen technology, each exhibit unique characteristics in multiple aspects. Capacitive touch Panel（CTP） The structure of CTP mainly consists of a glass panel, a conductive layer (such as ITO), an insulating layer (such as tempering glass or plastic), and another conductive layer. Its working principle is based on capacitive sensing, achieving touch functionality through human body current sensing. When a finger contacts the metal layer of the touch screen, a coupled capacitance is formed, and the precise location of the touch point is determined by calculating the current ratio flowing through four electrodes.   Advantages of capacitive touch: √  Support for multi-touch function. √  High light transmittance >85% and vivid colors. √  Fast response time is less than 3ms. √  Surface cover covers such as tempered glass of hardness up to 7H, offering excellent scratch resistance and durability. √  Endurance against various contaminants like water, fire, radiation, static electricity, dust, or grease. √  High life expectancy: each touch point capable of enduring over 50 million touches and maintaining cursor stability after calibration. Disadvantages: • High cost. • Incapability being operated with fingernails or insulating materials for touch input. • Unavailability use with gloves or when the screen is wet. • Easy interference from surrounding conductors and temperature variations.     Resistive touch panel(RTP) RTP, consist of a glass or organic glass base coated with a transparent conductive layer (ITO film), and a hardened and scratch-resistant cover whose inner surface is also coated of ITO layer. There are many tiny transparent insulating points between the two layers of conductive layers to separate them.   Resistive touchscreens operate based on the principle of resistance, determining touch location through pressure sensing. When the screen surface is pressed, the top layer is compressed, causing the two ITO layers to contact each other, resulting in a change of resistance value. The controller calculates the coordinates of the touch point based on the detected resistance change and performs corresponding operations accordingly. This technology requires physical pressure on the screen to register a touch.   Advantages of resistive touch: √ Lower cost √ Good response sensitivity and reduced susceptibility to misoperations. √ Ability to withstand various harsh environments, resisting dust and moisture. √ Compatibility perform with any object for touch input, non-conductive objects like pen.    √ Perform feasibility with gloves, or wet screen. Disadvantages: • Support for single-touch only • Slower response speed • Inferior light transmittance compared to capacitive screens • Outer film susceptibility to scratches, potentially rendering the touchscreen unusable • Limited lifetime Expectancy: hitting touch about 1 million and a strokes touch about 100,000 times for 4-wire RTP as an example.   In summary, CTP touch and RTP touch each have their strengths and weaknesses, suitable for different application scenarios.  For instance, capacitive touch may be more suitable for situations requiring high precision, vivid color reproduction, and fast response times, such as smartphones and tablets. On the other hand, resistive touch may be more appropriate for cost-sensitive environments, harsh conditions, or operations involving water or while wearing gloves, such as in industrial equipment and ATMs.