Assertion: cathode ray tube's electron gun | /r/CapableOf | focus the electron beam
Facets:
value: to strike the phosphor
type: PURPOSE
Source sentences:
text: The electron gun, which consists of the cathode, choke, accelerator, and lensing region, is the device which generates and focuses the electron beam used to project an image on the phosphor screen.
text: The electron gun also contains electrical coils or plates which accelerate, focus, and deflect the electron beam to strike the phosphor viewing surface in a rapid side-to-side scanning motion starting at the top of the surface and working down.