屏蔽层是薄膜开关的组成部分，起以下或更多的作用：

(1)将可能存在的有害静电安全地释放，避免敏感的电子元件受损害。

(2)屏蔽的薄膜开关，免受周围环境的射频干扰和电磁干扰。

(3)通过反射或吸收的方式减少或消除射频干扰和电磁干扰的辐射。

屏蔽层的效力和性能取决于屏蔽层材料的特性和结构，还取决于屏蔽源的频率和距离。电磁干扰屏蔽通常用于医学设备、军事、电信和许多其它的电子设备。因为这些设备安装了新式的辐射和抗干扰部件，屏蔽的重要性也就随此增加。

我企业以往应用的典型组装结构如下：

丝印导电银:通常被印刷在网状结构的聚脂上，以满足作业的特殊要求，此层在面膜层之下。

设计考虑因素:

(1)根据装配的条件，面膜层材料应具有足够的绝缘，以抵御静电，如：厚度为125µm的聚脂面膜层应可以承受15kV的电压。

(2)因为它应对面膜层表面提供足够的屏蔽，面板边缘处的薄弱处应给予细致的考虑。即使面膜层的绝缘相当良好，面板边缘附近的静电也会干扰面膜层周围，通过电路层的边缘进入面板。我厂会认真设计以保证避免此类现象并对此进行保护。

(3)我 企业的技术人员具有各种压片经验，能够帮助你解决各种特殊的有关屏蔽层的困难。

(4)顾客应提供一份详尽的所需屏蔽层的说明。一些高技术要求的屏蔽层价格比较昂贵，只是在特别需要的时候才考虑使用。

      注意： 磁场强度的减少由频率、屏蔽层材料导电率和材料厚度决定。屏蔽材料削弱或减少辐射场能量的等级与其屏蔽效率（SE）有关。SE的标准单位为分贝（dB）。它的值为屏蔽前后的电磁场强度的比值。SE的值每增加20分贝，表现为电磁干扰通过屏蔽物的泄漏值减少十倍。一个60分贝的屏蔽物减少磁场强度的值为原值的一千分之一（例如，从5伏特/米到5毫伏/米） 。

Introduction EL-erjiguan.htm

The shielding layer is a part of the film switch, which plays the following or more roles:

(1) to release the potential harmful electrostatic safety, to avoid the damage to the sensitive electronic components.

(2) shielding of the film switch, from the surrounding environment of radio frequency interference and electromagnetic interference.

(3) reduction or elimination of radio frequency interference and electromagnetic interference by reflection or absorption.

The effectiveness and performance of the shield depends on the characteristics and structure of the shielding layer, and also depends on the frequency and distance of the shield. Electromagnetic interference shielding is often used in medical equipment, military, telecommunications, and many other electronic devices. Because these devices are equipped with a new type of radiation and interference components, the importance of shielding also increased.

The typical assembly structure that my company used in the past is as follows

Screen printing conductive silver: is normally printed on polyester mesh structure, to meet the special requirements, this layer below the layer mask.

Design considerations:

(1) according to the conditions of assembly, the mask material layer should be with a sufficient insulation, against static electricity, such as thickness of 125 µ m of the polyester film layer should be able to withstand 15kV voltage.

(2) because it should provide sufficient shielding to the surface of the mask layer, the weak points in the edge of the panel should be given careful consideration. Even if the insulation of the mask layer is quite good, the electrostatic near the edge of the panel will interfere with the mask layer. I plant will be carefully designed to ensure that such phenomenon is avoided and to protect.

(3) the technical staff of my company has a variety of tablet experience, can help you to solve a variety of special shielding layer of the difficulties.

(4) the customer shall provide a detailed description of the required shielding layer. Some of the high technical requirements of the shielding layer is more expensive, but only in particular need to consider the use of.

Note: the magnetic field intensity is reduced by the frequency, shielding layer material conductivity and material thickness. Shielding material to weaken or reduce the level of radiation field energy and its shielding efficiency (SE). The standard unit of SE is dB (DB). Its value is the ratio of the electromagnetic field strength before and after shielding. The value of SE is increased by 20 dB, which is ten times as much as the leakage of electromagnetic interference through the shield. A 60 dB shielding to reduce field strength value is the original value of 1000, one (for example, from 5 V / m to 5 mV / M).