pioneered in these early tubes was applied practically in the design of vacuum tubes, particularly in the invention of the cathode ray tube (crt) by ferdinand braun in , which was used in television sets and oscilloscopes . today, electron beams are employed in sophisticated devices such as electron microscopes...
mw mw mi hq d sension+ ec dissolved oxygen mw mi sension+ do lux meter mw conductivity meters mi sension+ ec sension+ ec multi meters mi hq d hq d sension+ mm dissolved oxygen meter mi peroxide mi turbidity meter mi tu tl tungsten lamp tl led digital refractometer ma ma ma hrd series biological microscopes...