- A cathode ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams, which are directed and controlled to display images on a phosphorescent screen. The images may represent electrical waveforms on an oscilloscope, a frame of video on an analog television set (TV), digital raster graphics on a computer monitor, or other phenomena like radar targets. A CRT in a TV is commonly called a picture tube. CRTs have also been used as memory devices, in which case the screen is not intended to be visible to an observer. The term cathode ray was used to describe electron beams when they were first discovered, before it was understood that what was emitted from the cathode was a beam of electrons.
- This is a fairly lengthy and technical article. Start with beginner resources like YouTube if you are not already familiar with the technology.
- Schumacher Creek Natural Area Preserve (dnr.wa.gov)
This 499 acre preserve includes the headwaters of Schumacher Creek, the stream and associated wetlands, a shore-pine forested sphagnum bog, and an upland buffer. Within the wetlands and bog are a variety of plant communities that vary in their dominant vegetation. One of the plant communities found at Schumacher NAP, the Sitka alder/skunk cabbage-water parsley community, has a very restricted geographic range; it is only found in the Puget lowlands and is critically imperiled.
