Vidicon type camera tube
AssigneeHitachi, Ltd.
InventorsMasashi Mizushima, Masanori Maruyama, Shigeru Ehata, Masakazu Fukushima
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Abstract
A vidicon type camera tube comprising a beam current control section including a thermionic cathode, a first grid having an aperture of diameter d.sub.1, a second grid having an aperture of diameter d.sub.2 and a beam disc having a diaphragm of diameter d.sub.3 disposed at a distance of l along the tube axis from the second grid. The tube further comprises a main lens section constituted of cylindrical electrodes. The diameters d.sub.1, d.sub.2 and d.sub.3 and the distance l are so determined that the value of (d.sub.2 /l)(d.sub.3 /d.sub.1).sup.2 may lie in the range where the difference of the effective cathode loading is positive.
Claims1
A vidicon type camera tube comprising a beam current control section including a thermionic cathode, a first grid having an aperture of diameter d.sub.1, a second grid having an aperture of diameter d.sub.2 and a beam disc having a diaphragm of diameter d.sub.3 disposed at a distance of l along the tube axis from said second grid, and further comprising a main lens section, wherein said diameters d.sub.1, d.sub.2 and d.sub.3 and said distance l are selected to satisfy the relation of 2.48.times.10.sup.-3 <(d.sub.2 /l)(d.sub.3 /d.sub.1).sup.2 <5.48.times.10.sup.-3.
Dependencies are inferred from the claim text.