| 摘要 |
1,075,756. Making electron discharge devices; removing metal by fusion; soldering. GENERAL ELECTRIC CO. Sept. 4, 1964 [Oct. 3, 1963], No. 36450/64. Headings B3A, B3R and B3V. [Also in Division H1] In making an electron discharge device a body is positioned in or so as to close an envelope having a transparent segment and a coherent light beam is projected through the segment on to the body to heat the body and form an aperture therein. In making a light valve an electron gun (14), Fig. 1 (not shown), comprising a body (16), Fig. 2 (not shown) a box (18), a spacer (20), an end element (22) and electrodes (28, 30), Fig. 3 (not shown), is assembled in a jig and heated in a vacuum chamber mainly by radiation from the container which is heated by an induction coil arranged inside or outside of the chamber to effect brazing of the components by brazing material (19) and outgassing of the components. The gun is then hermetically sealed to a writing chamber envelope (12) by glass sealing and a vacuum pump (39) evacuates the envelope through a tube (40). Elements within the envelope are heated for outgassing by induction heating apparatus (44) and then the tube (40) is sealed. A coherent light beam generator (46) projects a beam (47) through a lens (48), through a transparent window (49) in the envelope, through a transparent disc (50) at a point bare of conductive substance (52) and through an aperture (53) in a light shield (54) on the end of element (22). The beam produces an aperture in the end of the element (22). The beam generator (46) comprises a laser having a synthetic ruby rod (60), Fig. 6 (not shown), doped with chromium about which is arranged a helical xenon-filled coil (61), one end of the rod having a deposited silver surface (62) for providing 100% reflection and the other end being coated to provide 90% reflection. A trigger pulse voltage derived from a source (65) is stepped up to 50 KV by a transformer (66) whose secondary winding is coupled to a trigger rod (67) which initiates discharge of the gas in the coil (61). The energy for maintaining the discharge is derived from a capacitor (68). |
