Disadvantages of capacitive touch screens

The transparency and clarity of capacitive touch screens are superior to four wire resistive screens, but they cannot be compared to surface acoustic wave screens and five wire resistive screens. Capacitive screens have severe reflection, and the four layer composite touch screen with capacitive technology has uneven transmittance of light of different wavelengths, resulting in color distortion. Due to the reflection of light between layers, it also causes blurring of image characters.
Current: Capacitive screens use the human body as an electrode of a capacitor component in principle. When a conductor is coupled with a sufficient capacitance between the ITO working surface of the interlayer, the current flowing away is sufficient to cause the capacitive screen to malfunction.
Although the capacitance value is inversely proportional to the distance between poles, it is directly proportional to the relative area and also related to the insulation coefficient of the medium. Therefore, when a large area of palm or handheld conductor is close to the capacitive screen instead of touching it, it can cause the capacitive screen to malfunction. This situation is particularly serious in humid weather. Holding the monitor with your hand, placing your palm within 7 centimeters of the monitor, or placing your body within 15 centimeters of the monitor can cause the capacitive screen to malfunction. Another disadvantage of capacitive screens is that they do not respond when touched with gloved hands or handheld non-conductive objects, due to the addition of a more insulating medium.
Drift: The main disadvantage of capacitive screens is drift: when the environmental temperature and humidity change, or when the environmental electric field changes, it can cause the capacitive screen to drift, resulting in inaccuracy. For example, if the temperature of the monitor rises after turning on, it will cause drift: when the user touches the screen and their other hand or body is close to the monitor, it will drift; Large objects near the capacitive touch screen will drift when moved, and if someone surrounds and watches when the user touches it, it will also cause drift; The reason for the drift of capacitive screens is due to inherent technological deficiencies. Although the environmental potential surface (including the user's body) is far away from the capacitive touch screen, it is much larger than the area of a finger, which directly affects the determination of the touch position.
Other: In addition, many relationships that should be linear in theory are actually nonlinear, such as the total amount of electricity absorbed by people with different weights or finger wetness, and the change in total current and the change in the four sub currents is nonlinear. The custom polar coordinate system used by capacitive touch screens does not have an origin on the coordinates, and the controller cannot detect and recover after drift. Moreover, the calculation process from the values of the four sub currents to the X and Y coordinate values of the touch point on the Cartesian coordinate system is complex after completing the four A/Ds. Due to the absence of an origin, the drift of the capacitive screen accumulates and often requires calibration at the work site. The outermost silicone protective glass of the capacitive touch screen has good scratch resistance, but it is afraid of being hit by nails or hard objects. If a small hole is knocked out, it will damage the interlayer ITO. Whether it is damaging the interlayer ITO or damaging the inner surface ITO layer during installation and transportation, the capacitive screen will not work properly.
Low precision: Due to technical reasons, the precision of capacitive touch screens is still lacking compared to resistive touch screens. And it can only be inputted with fingers, making it difficult to recognize complex handwriting input on small screens.
The cost will be relatively high: there will still be certain technical difficulties in the process of attaching the touch panel to the LCD panel for capacitive touch screens.