Franck-Hertz - University of Utah Physics
... A simplified diagram of the Franck-Hertz experiment is shown in Figure 1. In an oven-heated vacuum tube containing mercury vapor, electrons are emitted by a heated cathode, and are then accelerated toward a grid that is at a potential VGC relative to the cathode. Just beyond the grid is an anode, wh ...
... A simplified diagram of the Franck-Hertz experiment is shown in Figure 1. In an oven-heated vacuum tube containing mercury vapor, electrons are emitted by a heated cathode, and are then accelerated toward a grid that is at a potential VGC relative to the cathode. Just beyond the grid is an anode, wh ...
Introduction and Semiconductor Technology
... – phosphorus becomes positive ion after giving up electron ...
... – phosphorus becomes positive ion after giving up electron ...
Gas-filled Tubes
... usually larger in order to carry heavy currents. Gas-filled tubes are generally classified according to the type of emission used viz. (I) Cold-cathode type (II) Hot-cathode type In the cold-cathode type, the cathode is not heated as in a vacuum tube. The ionization of the gas is caused by the ...
... usually larger in order to carry heavy currents. Gas-filled tubes are generally classified according to the type of emission used viz. (I) Cold-cathode type (II) Hot-cathode type In the cold-cathode type, the cathode is not heated as in a vacuum tube. The ionization of the gas is caused by the ...
U3e Test Review Electrical Technology 1
... • Materials that resist current are called INSULATORS ___________. • Materials that provide LOAD a path for current are called ___________. CONDUCTORS • Current is measured in AMPERES (Amps) ...
... • Materials that resist current are called INSULATORS ___________. • Materials that provide LOAD a path for current are called ___________. CONDUCTORS • Current is measured in AMPERES (Amps) ...
PPTX - ecars
... crystal pumped at 885 nm for remote sensing, Photonics Technology Letters 26, 1890-1893, 2014. Fiocco, G., and Smullin, L.D., Detection of scattering layers in the upper atmosphere by optical radar. Nature, 199, 1275–1276, 1963. Grath, A., et al., Injection-seeded single frequency, Q-switched Er:gla ...
... crystal pumped at 885 nm for remote sensing, Photonics Technology Letters 26, 1890-1893, 2014. Fiocco, G., and Smullin, L.D., Detection of scattering layers in the upper atmosphere by optical radar. Nature, 199, 1275–1276, 1963. Grath, A., et al., Injection-seeded single frequency, Q-switched Er:gla ...
Photomultiplier
Photomultiplier tubes (photomultipliers or PMTs for short), members of the class of vacuum tubes, and more specifically vacuum phototubes, are extremely sensitive detectors of light in the ultraviolet, visible, and near-infrared ranges of the electromagnetic spectrum. These detectors multiply the current produced by incident light by as much as 100 million times (i.e., 160 dB), in multiple dynode stages, enabling (for example) individual photons to be detected when the incident flux of light is very low. Unlike most vacuum tubes, they are not obsolete.The combination of high gain, low noise, high frequency response or, equivalently, ultra-fast response, and large area of collection has maintained photomultipliers an essential place in nuclear and particle physics, astronomy, medical diagnostics including blood tests, medical imaging, motion picture film scanning (telecine), radar jamming, and high-end image scanners known as drum scanners. Elements of photomultiplier technology, when integrated differently, are the basis of night vision devices.Semiconductor devices, particularly avalanche photodiodes, are alternatives to photomultipliers; however, photomultipliers are uniquely well-suited for applications requiring low-noise, high-sensitivity detection of light that is imperfectly collimated.