Blocker
From Biocrawler, the free encyclopedia.
A blocker is the inverse of a filter, instead of blocking everything like the filter does, it lets everything else pass and blocks only the specified things.
For instance, an infrared blocker blocks out infrared light, and lets visible light (among other wave lengths) pass through. An infrared filter blocks the visible light and lets only the infrared pass.
A Blocker is also used in cell phone terminology: Cell Phone Blocker Read more at: http://www.cell-phone-jammers.com/cellular-phone-jammers.html
