GB1066592A - Image pickup tubes - Google Patents

Abstract

1,066,592. Television pick-up tubes. TOKYO SHIBAURA ELECTRIC CO. Ltd. April 16, 1964 [April 22, 1963 (3)], No. 15790/64. Heading H1D. An image pick-up tube includes a mesh electrode which is disposed adjacent the target electrode and is supported from the end of a cylindrical focusing electrode by the use of an insulating ring. An electron beam from the cathode (21), (Fig. 1, not shown), passes through grids (22) and (23), the three focusing electrodes (24), (25) and 26, Fig. 2, and the scanning electrodes (28) and (29), all mounted upon a set of glass or ceramic rods (27), and then passes through the electrode mesh 35 to strike the photo-conductive layer (15), the output signal from the conductive layer (14) being taken from the indium cold seal (16) of the end plate (12). Mesh electrode 35, Fig. 2, is supported from the enlarged end portion of focusing electrode 26 by the receipt within the latter of flange 41 of a metal ring, over the flange 42 of which is slid a glass or ceramic cylinder 30, into which is received the flange 43 of member 32, which itself receives flange 34 of the mesh support ring, the interposed spacer 36 extending to the envelope and protecting the target 13 from foreign particles within the tube. On assembly, members 31 and 32 are first attached to the cylinder 30 by inserting and welding metal pins 47, 48 through holes 45, 46-the flange 44 resiliently engaging the envelope wall-and flange 41 is then welded within electrode 26 prior to the insertion of electrode 33 with spacer 36 within member 32, and the cold sealing of the end-plate (12) of the envelope. A lens action is provided by maintaining the mesh 35 at a higher potential than the electrode 26. In a modification (Fig. 3, not shown), the ring 31 is dispensed with, and cylinder 30 is slid directly over a flange of reduced diameter at the end of electrode 26.