A lid, such as for example a glass cap, is coupled to the substrate such that the lid and substrate define a sealed cavity accommodating the sensing element (s).

一个盖帽，比如玻璃盖帽，与基底接合，从而盖帽和基底界定了一个容纳传感元件的密封谐振腔。

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The structure's cone-like shape was designed to reduce wind turbulence, yet there is only one piece of curved glass on the building: a lens-shaped cap at the very top.

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The solution was a vacuum cap that sits over the whole unit, much like the glass globe surrounding the tungsten filament in a flashlight bulb.

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