Venetian blind
3.At my office, I got good results by attaching the antenna to a venetian-blind slat and tinkering with the skyward aim.
5.The design and arrangement of an in-line analysis system of slow positron beam for molecular beam epitaxy is described and the analysis method using positron beam technique to study semiconductor films is introduced. In the slow positron moderator, a combination of tungsten-rings and "Venetian blind" structure are used to obtain a higher efficiency of conversion from fast to slow positrons.

