May 30, 1939. H. HARRIS ' 2,160,434 TELEVISION APPARAIUjS Filed July. 18. ‘1936

IN VEN TOR. _ (Kara/r 14919471.: B Y '

A- ORNEYS. Patented May 30, 1939 ; a - A, . _ 2,160,434

sums PATENT OFFICE 2,160,434, TELEVISION APPARATUS Huston Harris, Corning, N. Y., assignor to Corn ing Glass Works, Corning, N. Y., a corporation of New York Application July 18, 1936, Serial No. 91,403 2 Claims. (Cl. 250—-141) Mly invention relates to improvements in tele the envelope to a blown body portion thereof; ' vision apparatus and the like, and particularly the pre-formed body being produced in any well to the improvement of the optical ?delity of such known manner, as by pressing, or by forming apparatus. and subsequently grinding and polishing in ac In the past it has been common practice to cordance with the degree of perfection desired. 5 manufacture envelopes for cathode ray tubes, In the drawing: used in television receivers to display images Fig. 1 is a side view of a cathode ray tube hav translated from picture signals received, by blow ing an envelope embodying this invention; Fig. 2 is a side view, in section, of the blown ing the envelopes to the desired contour. The and pressed parts of the envelope shown in Fig. 10 10 shape of the envelope usually is that of a fun 1 before they are sealed together; nel, closed at the large end to form a screen upon which the images are displayed; and hav-v Fig. 3 is a side view of an iconoscope tube ing the electrical elements constituting an elec having an envelope embodying this invention; Fig. 4 is a view, similar to Fig. 2', of the parts tron gun for developing a cathode ray and for of an iconoscope tube envelope embodying this 15 directing the same at the screen to produce invention; and images thereon, mounted in the stem. A simi Fig. 5 is an end view of the intermediate part lar practice has also been followed in the manu facture of the iconoscope tube which serves as of the envelope shown in Fig. 4. In the cathode ray tube the envelope is com. a means for viewing scenes for television trans posed of a blown glass body portion [0, the large 20 mission and similar applications, and which is 20 composed of an envelope containing an electron end of which is carefully ground and sanded to gun focused on a photosensitive signal plate free it of any metallic inclusions, and then > welded or fused to a similarly prepared surface Within the tube to develop picture signals in ac of a saucer-like pressed glass part II having a cordance with re?ections received on the photo sensitive signal plate of objects or scenes within concaVo-convex screen or rounded area l2 in 2 which the mass of glass is of uniform thickness View of a window comprising a part of the tube and curvature throughout. If desired, the screen envelope structure. may be of plano-parallel con?guration, but the In the blowing of a glass body it is impossible concavo-convex con?guration gives the exposed to obtain a perfect distribution and uniform surface of the screen greater resistance to frac- 30 30 thickness of glass in the wall, and while in ordi nary vacuum tubes this may not be important, ture, and also corrects distortion caused by the it is highly important in a cathode ray tube that changing curvature of the ?eld with distance away from the cathode when a plano-parallel the distribution, thickness and contour of the glass in that portion of the wall serving the screen is used. An electron gun I3 of any known form is sealed in the neck of the envelope and 35 screen be uniform, as otherwise distortion of the image produced thereon will result. For similar is directed toward the screen area l2 in the usual 35 reasons it is important that the thickness and manner. contour of ‘the window of an iconoscope tube be The iconoscope tube envelope comprises a uniform, as otherwise the object re?ections on main body in the form of a cylinder l6, the one 40 the signal plate will be distorted and ?delity of end of which is ground, sanded and then welded 40 transmission and reproduction will be seriously or fused to a similarly prepared surface of a impaired. saucer-like part of pressed glass or the like hav An object of the present invention is to trans ing a plane-parallel screen or window area l8 mit and reproduce pictures and views with ?del within its wall areas l9 and 20. The lower wall area 20 has a protuberance 2| partly ground 011 ity. 45 Among its features my invention embodies a at the point' indicated (Fig. 4) by the interrupted cathode ray tube envelope having a screen por line H to form an apertured seat 22 to which tion on which picture signals will be developed a tubular part 23 of the envelope is welded at with perfect ?delity; also, an iconoscope tube such an angle with respect to the axis of the envelope having a window therein through which cylinder it that an electron gun 24, sealed in the 5 6 O light, re?ected from objects or scenes within remote end of tube 23, can scan the usual photo- 0 view of the window, will pass without distortion. sensitive mosaic surfaced signal plate 25 to de Other features embody the production of a velop picture signals in accordance with light vacuum tube envelope by sealing or welding a re?ected from. objects or scenes within view of 55 pre-formed optical screen or window portion of the window area [8. 65 2'. a “ “ 2,160,434 It will be apparent from the foregoing that disposed with respect to the line of juncture‘ of by the use of a combination of blown and pressed the respective sections. glass parts I am able to produce envelopes for cathode ray and iconoscope tubes or the like 2. A glass envelope which includes two sepa having screen or window areas of perfect optical rately fabricated hollow parts one of which is ?delity. adapted to transmit light generated within the 5 What is claimed is: envelope, said parts being arranged in juxta posed relation and fused together at their ad 1. An electron tube envelope made of glass joining edges and the light transmitting part be which includes pressed optical and blown non ing so shaped that the larger portion thereof is 10 optical hollow sections arranged in juxtaposed in a plane remotely disposed with respect to the 10 relation and fused together at the adjoining line of juncture of the respective parts. edges, the optical section being so shaped that the major portion thereof is in a plane remotely HUSTON HARRIS.