显示屏表面空气式静电放电实验特性

Experimental characteristics of surface discharging for air electrostatic discharge on display

显示屏是人机交互的重要部件,当人体静电放电发生在显示屏表面时,有可能导致软硬故障。为了研究显示屏空气式静电放电实验特性,通过一个自制的装置对显示屏空气式静电放电电流和通过显示屏的位移电流进行了实验测量。研究发现:放电电流峰值随接近速度的增加而增加,上升时间随接近速度的增加而减小。在±10~±12kV电压范围,受电弧长度的影响,上升时间增大,电流峰值变小。随着测量点与放电点之间距离的增大,位移电流波形峰值减小、上升时间增大,正极性放电峰值更大且扩散范围更广,而负极性放电上升时间增大更加明显。由位移电流波形及其分布可以计算出电荷密度。电荷密度随距离放电位置距离的增大而减小。与正极性相比,尽管负极性放电电流峰值较低,但电荷密度较高,说明负极性放电具有造成更高等级损伤风险的危害。

The display is an important part of human-computer interaction.When the human body electrostatic discharge occurs on the surface of the display,it may lead to hardware and software faults.In order to study the experimental characteristics of air electrostatic discharge on display,the air electrostatic discharge current and the displacement current through the display screen were measured by a self-made device.It is found that the peak value of discharge current increases with the increase of approaching velocity,and the rising time decreases with the increase of approaching velocity.In the voltage range of ±10-±12 kV,the rise time increases and the peak current decreases under the influence of arc length.With the increase of the distance between the measurement point and the discharge point,the peak value of the displacement current waveform decreases and the rising time increases.The peak value of the positive polarity discharge is larger and the diffusion range is wider,while the rising time of the negative polarity discharge is more obvious.The charge density can be calculated from the displacement current waveform and its distribution.The charge density decreases with the distance of discharge position increasing.Although the peak value of negative polarity discharge current is lower than that of positive polarity,the charge density is higher.This indicates that the negative polarity discharge has a higher damage risk.