US2307505A - System of communication - Google Patents

Description

Jan. 5, 1943. F. HEINMETS SYSTEM OF COMMUNICATION Filed July 24, 1941 I TRANSMITTER AMPLIFIER lbw/NA 11/0 fiQi/VME Ts INVENTOR. Q Mrwu ATTORNEY Patented Jan. 5, 1943 UNITED STATES PATENT, OFFICE SYSTEM OF COMMUNICATION Ferdinand Heinmets, New York, N. Y.

Application July 24, 1941, Serial No. 403,811 4 Claims. (01. 178-637) My invention relates to systems of communication and has particular reference to the art of telegraphic communication.

In the transmission of messages by radio or telegraph it is important to send as many messagesas possible in-a given time over a given channel of communication in order to utilize this channel to the fullest extent.

My inventita has for its object to provide means for rapid transmission of messages over any ordinary channels such as wires or radio waves. I employ for this purpose a receiver having a Braun tube with a fluorescent wall or screen of a type similar to the devices used in oscillographs, television, etc., an electron beam being directed on the screen and controlled by magnets or electrostatic plates. Th beam is made to move in certain patterns so as to produce images of certain characters or symbols which are then photographed on a moving film or strip of light-sensitive paper. Corresponding signals are sent to the receiver by a transmitter employing a moving film with two sets of tracks for the two sets of electron beam directing elements, the light impulses being converted into electric impulses by a photocell.

Although it is possible to provide an intermittent motion for the transmitting film in order to produce separate images of the symbols or characters, I prefer to move the film continuously, so adjusting the light tracks that the symbols will appear on the screen in their correct shapes or proportions.

My invention is' more fully described in the accompanying specification and drawing, in which:

Fig. l is a diagrammatic view of a communication system utilizing my invention;

Fig. 2 is a view of a typical symbol transmitted by my system;

Fig. 3 is a diagram of the same symbol distorted for transmission on a continuously moving film;

Fig. 4 is a voltage curve for longitudinal deflections of the electronic beam in a receiving tube;

Fig. 5 is a similar voltage curve for the transverse deflections of the electronic beam;

Fig. 6 is a diagrammatic, view of a device for preparing a transmitting film.

My system of communication as shown in Fig. 1 consists of a transmitter and receiver connected together byany suitable channel of transmission. Wired connections are shown by way of example, although, of course, radio transmission can be also used.

The transmitter comprises a transmitting film l placed in front of two sources of light 2 and 3. The film is moved by a cylinder or spool 4, being unwound from a similar cylinder or spool 5. The film has two tracks 6 and l, transparent to the light, the rest of the film being opaque. The light from the sources 2 and 3 is directed by condenser lenses 8 and 9 on the respective tracks through slits l0 and H in a screen l2 and passes to photocells 13 and I4. The latter are included in two separate electric circuits l5 and I6 of a transmitter and amplifier IT. The circuits are separately transmitted through channels l8 and I9 to a receiver 20. A single channel may be also used if different frequencies are employed for the two circuits.

Signals transmitted through the channels are amplified in the receiver 20 and are conducted by leads 2| and 22 to two sets of plates 23 and 24 in 9. Braun tube 25. The plates are placed at right angles to each other for correspondingly directing an electronic beam emitted by a filament 26 and passing through a slit in a grid 21.

The beam strikes a fluorescent screen 28 at the end of the tube and is photographed on a moving film or strip of light-sensitive paper 28. Instead of scanning the screen by the beam as in ordinary television apparatus, I vary the voltage applied to the plates 23 and 24 in such manner that the beam is made to move in various directions for drawing the outlines of symbols of which messages are composed, the intensity of the beam remaining constant. Thus, if it is desired to transmit a letter K, Fig. 2, the beam is made to move along the lines of the letter back and forth until the outline is completed.

Messages can be transmitted over my system at a high rate of speed by moving the paper strip 29 continuously. In order to prevent distortion of the images due to the movement of the paper, the images are continuously advanced by horizontally advancing the electron beam. Thus, the letter K is projected as shown in Fig. 3, the horizontal points being displaced forward by amounts proportional to the'total displacement L taking place during the interval of time from the beginning to the end of the letter writing operation.

beams passing through the slits ill and II and, therefore, the voltage transmitted to the plates 23 and 24.

The zero voltage point is indicated at in Fig. 3 and at the beginning of the tracks or voltage curves in Figs. 4 and 5. As shown in Fig. 5, the vertical voltage is gradually raised to a point a while the corresponding horizontal voltage is increased by only a small value b. The electron beam therefore draws a line Ob, Fig. 3. The vertical voltage is then brought down to a point 0 while the horizontal Voltage is correspondingly raised to d, as shown in Fig. 4-, the beam therefore moving to a point cd in Fig. 3. The horizontal voltage is then reduced to a point e while the vertical voltage is raised to a point I, the beam reaching a point ef in Fig. 3. The beam is then moved in the same manner through points ef, gh, i7, mn and, finally, to a starting point 0. The letter therefore continuously advances on the screen 28 at the same rate at which the paper strip 29 is moved, so that the correct outline of the letter K will be printed on the paper.

Upon completion of plotting the letter, the beam must be brought back to the starting zero point 0 along the line mn0. Since it is not desirable to have this line appear on the completed symbol, the zero point is covered by the edge of an opaque masque 34, shown in dotted lines in Fig. 2, so that an added potential V0 is required for the vertical movements (Fig. 5), bringing the zero point 0 above the end point 0' of the latter and above the point cd, Fig. 3.

Every letter or symbol must have a correspondingly outlined transparent area on the tracks 6 and 1. The tracks can be produced by using a light-sensitive film 3| and successively projectinglight beams 30, Fig. 6, through stencils or masks 32, 33. The selection of the stencils or masks can be made by any convenient method, the selected stencils being, for instance, automatically placed in position when a corresponding key of a suitable keyboard is depressed.

In a simplified system a single track can be used with a single transmission channel, so as to cause the electron beam to move in a straight line. A succession of dots and dashes can be thus obtained for transmitting intelligence in a Morse system.

It should be noted that instead of using the film l with transparent tracks, it is possible to print the tracks on a paper strip and use reflected light for the photocells.

It is understood that my system of communication may be further modified without departing from the spirit of the invention, as set forth in the appended claims.

I claim as my invention:

1. A system of communication comprising a transmitter and a receiver, a strip of an opaque material at the transmitter having two parallel tracks consisting of a plurality of interrupted transparent portions, means to move the strip, a stationary screen with two slits extending transversely of the tracks, means to pass light beams through the slits, means to convert the beams passing through the slits and tracks into two sets of electric signals, the intensity of the signals being determined by the width of the tracks, a Braun tube at the receiver, means to apply the two sets of the signals to the tube for causing movement of an electron beam in the tube, the tube having a fluorescent screen for the electron beam, the pattern of the tracks being such as to cause the electron beam to move in various directions while retaining unchanged intensity, thereby forming predetermined symbols on the screen, and a mask for covering the marginal portions of the screen where the beam starts and ends the symbols.

2. A system of communication comprising a transmitter and a receiver, a strip of an opaque material at the transmitter having two parallel tracks consisting of a plurality of interrupted transparent portions, means to move the strip, a stationary screen with two slits extending transversely of the tracks, means to pass light beams through the slits, means to convert the beams passing through the slits and tracks into two sets of electric signals, the intensity of the signals being determined by the width of the tracks, a Braun tube at the receiver, and means to apply the two sets of the signals to the tube for causing movement of an electron beam in the tube, the tube having a fluorescent screen for the electron beam, the tracks being formed in standardized patterns corresponding to predetermined symbols to be reproduced on the screen.

3. A system of communication comprising a transmitter and a receiver, a strip of an opaque material at the transmitter having two parallel tracks consisting of a plurality of interrupted transparent portions, means to move the strip, a stationary screen with two slits extending transversely of the tracks, means to pass light beams through the slits, means to convert the beams passing through the slits and tracks into two sets of electric signals, the intensity of the signals being determined by the width of the tracks, a Braun tube at the receiver, and means to apply the two sets of the signals to the tube for causing movement of an electron beam in the tube, the tube having a fluorescent screen for the electron beam, the tracks being formed in standardized patterns with angular contours so as to cause the electron beam to move in various substantially straight directions for forming selected letters of the alphabet on the screen.

4. A system of ;communication comprising a transmitter and a receiver, a strip of an opaque material at the transmitter having two parallel tracks consisting of a plurality of interrupted transparent portions, means to move the strip, a stationary screen with two slits extending transeversely of the tracks, means to pass light beams through the slits, means to convertthe beams passing through the slits and tracks into two sets of electric signals, the intensity of the signals being determined by the width of the tracks, a Braun tube at the receiver, means to apply the two sets of the signals to the tube for causing movement of an electron beam in the tube, the tube having a fluorescent screen for the electron beam, th tracks being formed in standardized patterns with angular contours so as to cause the electron beam to move in various substantially straight directions for forming selected letters of the alphabet on the screen, and a mask for covering on the screen the starting and finishing positions of the beam.

FERDINAND HEINMETS.

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