针孔

The formation mechanism of orange valvule-like pinhole in rolled aluminium foil was investigated by using optical microscopy,scanning electron microscopy,and energy dispersion X-ray spectrum.

利用光学显微镜、扫描电镜、能谱等试验手段对铝箔中"桔瓣"形孔形成的原因进行了。

Pinhole. A short unwelded area in the weld line extending through the entire pipe so that fluid will leak out through the area very slowly.

孔。指焊缝线上位焊接的、贯穿管子整个壁厚的细孔，可导致流体该孔缓慢漏出。

Telocentric lenses work with a wide depth of field. With a telocentric lens, you can image objects of different distances from the lens and the objects stay in focus.

端着丝粒的镜头(注:我猜是类似于孔镜头吧)有阔之景深，以端着丝粒的镜头，你能够将由镜头不同距离之目标物成像和保持目标物在焦。