Патент USA US2404839код для вставки
July 30, 1946. _ J. H. HAMMOND, JR l 2,404,839 SECRECY COMMUNICATION SYSTEM Filed Aug. 22, 1941 3 Sheets-Sheet 1 »25 0 m ., NN I\MWX «L _ am J0 H NBHY A .Y m5. f VHI.V .N „ÜRM mAmM, D J R. w„ ,/, July 30, 1946. 2,404,839 .1. H. HAMMOND, .1R SECRECY COMMUNICATION SYSTEM Filed Aug. 22, 1941 canos-„ .nìï a mnauïíî 5 Sheets-Sheet 2 w_ œ m œ m.c nn. M_ œ R M P_ P_H m P. w .„... w, fu. w u.. .m0 E / E ._.. PULL-DUWN |’///ß| FRAMEl I PULL-Down PULL-Down ~PULL-Down |’/////Ál FRAME 5 V//M FRAME`2. L5! M52 LIGHT FLAsHas VSCAIU L _ lNvENïoR 53 _ JOHN HAYs HAMMoNn, JR. July 30, 1946. J, H_ HAMMOND, JR 2,404,839- SECRECY COMMUNICATION SYSTEM Filed Aug. 22, 1941 3 Sheets-Sheet 3 EY Patented July 30, 1946 2,404,839 FFICE UNITED STATES, «PATENT o sEcREcY COMMUNICATION SYSTEM John Hays Hammond, Jr., Gloucester, Mass., assignor to Radio Corporation o1' America - 1 Application August 22, 1941, serial No. 467,891 ‘ 4 claims. (ci. 17a-_6.7) 2 This invention relates to secrecy communica- . tion systems and more particularly to a system for communicating messages by television. 'I'he invention further relates to means for in‘- . and 22> 'I‘he sprocket 2I is driven intermittently by anintermittentcam and spider-follower 23 of the early Powerstype, in which the throws are 10 cated 144° and 216° apart respectively. This serting a message in a single frame of a television 5 mechanism is driven by a 3600 R. P. M. synchro moving picture transmission system and means for recording this message on a moving picture film. ' y The invention’also relates to means for send nous motor 24 thru a bevel gear and pinion 25-26 having a 5:1 ratio. Mounted on the shaft of the motor 23 is 'a shutter disc 21 which is provided with a slot 28. I ' _ ing a message as a single frame of a, television 10 Light from a source of illumination, such as transmission system at a predetermined time and ‘ an electric arc 29 passes thru a lens system 30, means for receiving the message on a photo the light gate I9, film I1, and a second lens sys- » graphic film. tem 3| and is focused upon the iconoscope mosaic 32. The iconoscope I2 isof standard and well 15 known construction and is provided with the usual The invention also consists in certain new and horizontal and vertical deflection coils 35 and 36 original features of construction and combina which are connected to the deflection amplifiers tions of parts hereinafter set forth and claimed. 31.y `The iconoscope mosaic 32 is connected thru Although the novel features which are believedv an output circuit 38 to the amplifier I3. to be characteristic of this invention will be par 20 A synchronizing generator 39 is connected to ticularly pointed out in the claims appended here the amplifier I 3 and controls the speed of the mo to, the invention itself, as to its objects and ad “ tor` 24. Control equipment 40 is -connected to the vantages, the mode of its operation and the man amplifier I3 and the transmitter I4 is provided ner of its organization may be better understood with the usual antenna 4I. A light souce 42 is by referring to the followingr description taken 25 located near the gate I8 and is focused by‘a lens 'I'he invention also relates to a novel and im proved television receiving system. ' in connection with the accompanying drawings forming a part thereof, in which Figure 1 is a schematic diagram of a, typical A 43 upon a photo-electric cell 454 which is connected to the control potential means 46 which in turn is connected to the lamplifier I3. The sound head transmitter which may be utilizedin a system 41 is connected to the amplifier I3. embodying the present invention. " 30 The ñlm I1 used in this invention may be the Figure 2 illustrates a section of ñlm used in the standard motion-picture ñlm with one or more transmitter shown in Figure 1. of the picture frames replaced by the message 50. Figure 3 illustrates diagrammatically the se (Figure 2.) This replacement may be done in quence of events in the transmitter shown in Fig any lmanner well'known in the art, such as cut ure 1. 35 ting the film and inserting a section bearing the Figure 4 is a schematic diagram of a. receiver message. embodying the present invention. ` Operation Like reference characters denote like parts in the several ñgures of the drawings. In the operation of the transmitter shown in In the following description and in the claims 40 Figure 1 the film I1 is movedintermittently by parts will be identified by 'specific names for con venience, but they are intended to be as generic in their application toy similar parts as the art will means of .the cam and~spider-follower 23. The cam is driven at 12 revolutions per second by the synchronous motor 24 which runs at 3600 R. P; M. permit. 'I'his causes the ñlm I1 to be pulled down at un' Referring to the accompanying drawings and 45 equal vintervals as the throws of the cam are lo-v more particularly to Figure 1, a standard tele `cated 144° and 216? apart. ’I'he motion of the vision, film transmitter is shown comprising a mo film` I1isshown at 5I in Figure 3 in which .the tion picture projector II which projects a stand shaded areas indicate the pull down motion. 'I'he ard film upon an iconoscope camera I2, the out light fromv the arc 29 after passing thru thegate put circuit of which is connected to the necessary 50 I9 is chopped60 times per second «by the shutter amplifiers I3 and radio transmitter I4. 21. The shutter 21 is so timed relative to the cam The projector I I is provided with the usual feed 23 that the film I 1 is always stationary 'when the and take up reels I5 and I6 upon which is wound light flashes occur. The 'sequence of light flashes the film I1. The film I1 passes thru two gates -is indicated at 52 in Figure 3. These light flashes " I8 and I9 and over a number of sprockets 20, 2l 55 are fofonly M205 second duration. 3 The chopped light after passing thru the shut ter 21 is focused upon the iconoscope mosaic 32. ` This mosaic is scanned 60 times per second as gears 91--98 which have a 1:5 ratio. The diner ential 96 is operated by a lmurled knob 99. The motor 95 is driven from a power ampliñer |00 indicated at 53 in Figure 3. The scanning periods which is controlled by a frequency multiplier |6| 53 occur between the light flashes 52 so that the Cl connected to the sawtooth generators 10. The television picture signal is produced and trans sound recorder 82 is operated by a sound ampli mitted during periods when no optical image is fier |02 connected to the main amplifier 6|. on the mosaic 32. During these periods, how Operation ever, an electrical image is present on the mosaic In the operation of the receiver depicted in Fig 32 in the form of bound electrostatic charges on the minute photo-sensitized silver globules com _ure 4; the television program is received by the antenna 86 and is fed to the main ampliiier 6| prising the mosaic'32. During the scanning periods the sensitized which, for example, may consist of a first de tector, three stages of intermediate frequency mosaic 32 is scanned -by a moving beam of elec amplification and a second detector and -syn trons 55 which is caused to scan the image on the chronizer. «'I'he output from the second detector mosaic 32 by means of the deflection coils 35 is fed to the video ampliñer 62 where the pic and 36 in a well known manner. The deilection ture signal is ampliñed and fed directly to the coils 35 and 36 are energized from the deñection cathode ray tube 63. The second anode of the amplifiers 31 which are controlled by the syn chronizing generator 39 acting thru the amplifier 20 tube 63 is supplied with high voltage, for exam |3. As the synchronizing generator 39 also con ' ple, 200 volts direct current, from the full wave rectifier 66. Low voltage power may be supplied trols the synchronous motor 24, the operator can to the tube 63 from a source not shown. ,make the short 1A200 second light flashes fall with The canning and synchronous control auxil in the 1/300 second intervals between the vertical' scanning periods with some tolerance on each 25 iaries make use of the second stage of the second detector, which may be used as a clipper rectifier side as depicted in Figure 3. to provide the synchronous pulses separated from 'I'his arrangement of moving film and scanning the picture impulses. The output of the clipper is necessary as the standard ñlm moves at the rectiñer leads to the synchronous amplifier 'Il aver‘age rate of 24 frames per second while the television apparatus operates at 30 frames per 30 which acts to separate the vertical synchronous pulses from the horizontal. The sawtooth gen second and 60 fields per second, interlaced, so erators 10 may include a blocking oscillator and that the projector must flash a still picture on‘the discharge tube which may be used to develop mosaic every léo of a second with each flash last sawtooth waves of voltage under control of the ing about 9h00 second. < A fuller description of the construction and op 35 vertical impulses and a second blocking oscil lator and discharge tube may be used to develop eration of the transmitter is set forth on pages sawtooth waves of voltage for the horizontal di 48-61 in the R. C. A. review, volume IV, 1939 rection. The outputs of these two circuits con 1940. It is to be understood that this particular trol the vertical and horizontal deflection ampli transmitter is described merely as an example of a suitable system to which this invention may 40 ñers 69 which in turn control the operation of the vertical and horizontal deflection coils 61 and be applied and that other devices capable of scanning a motion picture ñlm and transmitting 'I'he television picture is produced on the fluo the scanned image may be used. rescent screen of the cathode ray tube 63 in The receiver embodying the present invention is shown in Figure 4 as comprising an antenna 45 the usual manner, the picture signal being sup plied by the video amplifier 62 and the cathode» 60 which is connected to the input of the ampli ray beam being deflected by means of the coils ñer 6|, the output of which passes thru a video 61 and 68. As already described the picture on amplifler 62 to a cathode-ray tube 63. An oscil the screen will consist of two images of frame lator 65 is connected .to the amplifier 6| and a high voltage supply source 66 is connected to the 50 |, three images of yframe 2, two images of frame 3, etc. As only one image of each frame is to be tube 63,V The deñection coils 61 and 68 of the tube photographed the disc 89 is provided with the 63 are connected to the deflection ampliñers 69 two slots 90 and 9|, which are 144° and 216° apart which in turn are connnected to the sawtooth respectively. The disc 89 is rotated at t’s the generators r10. The sawtooth generators 18 are controlled by the synchronous ampliñer 1| which 55 speed of the disc 21 (Figure 1) or one revolution in 2/24 second. ’I'his speed of rotation is accom is connected to the main amplifier 6|. plished by driving the shaft 88 from a synchro For making a photographic record of the pic nous motor 95 thru a set of bevel gears 98-91 tures produced by the cathode ray xtube 63, a mov having a 5:1 ratio. 'I'he motor 95 is driven in ing picture camera apparatus 15 is provided. The sensitized iilm 16 of this apparatus is un 60 synchronism with the motor 24 from the power ampliñer |00, which is controlled by the fre wound from a supply reel 11, passes over a sprock quency multiplier |0|, which in turn is controlled et 18, thru a. ñlm holder 19, over sprockets 80 by the sawtooth generators 10. and 8|, thru a sound recorder 82 and is wound The shaft 88 drives the cam 85 at the same upon a take up reel 83'. The sprocket 80 is driven intermittently by an 65 speed as the disc 89 by means of the 1:1 ratio bevel gears 86--81. The cam 85 drives the intermittent cam and spider follower 85, which is sprocket 80 intermittently so that the ñlm 16 is similar to the cam and spider-follower of Fig drawn down twice during each revolution of the ure 1. The cam 85 is' driven by a 1:1 ratio bevel disc 89. This draw down motion takes place gears 86--B1, the latter >being secured to a shaft 88 to which is attached a shutter disc 89. The 70 when the slots 90 and 9| are not in line with the axis of the lens system 92-93. =The differential shutter 89 is provided with two slots 90 and 9| 99 is used to obtain the proper relationship be and passes between two lens 92 and 93 which focus tween the slots 90 and 9| and the scanned the television image upon the iilm 16. The shaft images. When the slots 90 and 9| are in line 88 is driven from a 3600 R. P. M. synchronous motor 95 thru a diiïerential 96 and a set of bevel 75 with the optical axis of the system one image of 5 . «refinancel each frame will be completely scanned on the screen of the tube 63' and a photographic record of each frame will therefore be made on the tllm 19 which will include the frame 50 containing the message. , When the iilm 16 is developed and printed it is slowly run thru a standard type of projector until the frame 50 containing the desired mes sage is projected on the screen where it may be read or an enlarged photographic record of it made. The system may be operated for only a very brief interval of time by opening the circuit oi.' system could then be put in operation at a pre determined time, the mechanical apparatus syn chronized and as the message frame 50 ap ñlm at the transmitter. ~ ¿ 2. The method of secret communication which comprises incorporating a message on a single frame of a standard ymotion picture nlm, trans mitting said message by television during an in terval of about one-sixtieth of a second. receiving the transmitted message at a remote point, n transferring the same onto a sensitized motion picture ñlm. and developing said'ñlm to thereby reproduce said message. ‘ the video amplifier in the transmitter so that . only the synchronizing signal is transmitted. The 6 and developing said film to reproduce said mes sage together with the transmitted picture in’ the frame ~sequence corresponding to' that of the 3. 'I'he method of secret communication which - comprises. inserting a message between picture frames on a standard motion picture ñlm, scan- . ning said ñlm, transmitting the images thereof ' by television, receiving said images at a suitable proaches the picture gate I9 the circuit of the receiving point, impressing the same photograph video amplifier could be automatically or man 20 ically on a, sensitized motion picture iìlm at said ually closed and a few frames of the. picture point, and developing said film to reproduce said transmited which would include the message message together with the transmitted picture frame 50. In this way the signals would be in the frame sequence corresponding to that of transmitted for only a fraction of a second, thus the ñlm at the transmitter. A increasing greatly the secrecy of the system as 25 4. The method of secret communication which there would not be time for unauthorized per comprises the steps o1' inserting a single ñlm sons to tune in on the video signal. ~ frame area of a graphical message representa. Although only a few of the various forms in tion at predetermined spaced positions in a se which this invention may be embodied have been quence of iilm frame areas of pictorial repre shown herein, it is to be understood that the 30 sentations, scanning all of the film frame areas invention is not limited to any specific construc of the graphical and pictorial representations in tion but might be embodied in various forms sequence to produce signalling energy repre without departing from the spirit of the inven tion or uthe scope of the appended claims. What is called is: 1. The method of secret communication which comprises inserting a. message on a single frame sentative of the scanned iilm frames, and trans mitting the produced signalling energy with the v 35 two groups oi' signals in an associated and inter . mingled relationship whereby the signalling en- - ergy representative of the graphical iilm frame of a standard motion picture film, scanning said areas -is substantially masked and rendered secret nlm, transmitting the images thereof by tele in the transmission by the predominating se vision. receiving said images at a suitable receiv 40 quence of picture signalling energy..v ` ' ~ ing point, impressing the same photographically on a sensitized motion picture ñlm at said point. JOHN HAYS HAMMOND, Jn. '