US1714705A

US1714705A - Sender for picture transmission and method of sending pictures and the like

Info

Publication number: US1714705A
Application number: US28631A
Authority: US
Inventors: Wildhaber Ernest
Original assignee: Individual
Current assignee: Individual
Priority date: 1925-05-07
Filing date: 1925-05-07
Publication date: 1929-05-28
Anticipated expiration: 1946-05-28

Description

' y 28, 1929- E. WILDHABER I 4.705

SENDER FOR PICTURE TRANSMISSION AND METHOD OF SENDING PICTURES AND THE LIKE Filed May 7, 1925 2 Sheets-Sheet l INVENTOR.

6 FIQJ] Flq E. WILDHABER SENDER FOR PICTURE TRANSMISSION AND ME May 28, 1929.

THOD

OF' SENDING PICTURES AND THE LIKE 2 Sheets-Sheet Filed May 7, 1925 ;IlIllIIIIIIlII/}7/; IIIIIIIIIIIII/II Fl q 12 IN VEN TOR.

Pans 28,1929. v 1,114,705 1 UNITED STATES IPAIAVTENT OFFICE."

ERNEST WILDHABER, OF ROCHESTER, YORK.

' SENDER FOB PICTURE TRANSMISSION AND METHOD OF SENDING PICTURES AND THE LIKE.

' Application filed May 7, 1925. Serial a... 28,631.

My invention relates to the transmission My invention has two principal applicaof pictures, telegrams, and the like by electrons. When applied to the transmission of tricity, and is equally well applicable. to pictures, by wire or wireless telegraphy, it transmission by wire, and to transmission by constltutes an improvement of a known art.

5 wireless telegraphy. Another,not less important application is One object of my invention is to provide the copying transmission of telegrams,

a method and means eto send pictures and whereby an original letter or telegram is the like in a most direct manner and with automatically copied at a distant receiving high speed. v station. Hitherto telegrams had to be trans- 10' A further object is to provide a method formed to a telegraphic key, which transand means for sending telegrams directf rmation Il t eldom is a. a e Of errors, ly from a customers original, without interlike any human operation. In the intended mediate steps being taken. In other words, copying transmission of telegrams, the said 7 a copying transmission of telegrams is source of errors is done away with. a

15 aimed at, ex uding the human element, to As will be explained hereafter, transmis- I avoid errors, while reducing cost by dission of telegrams is made possible by elimipensing with ii ltermediate steps. natlng intermediate steps inherent to the i still further purpose is to provide means kn wn pr ss s Oiiri tran ss ya d for picture transmission, that shall have no by Speeding up the transmitting operation.

2 inertia. r I I *orconvenience the subject tobetransmit- 76 Another object is to project a picture to ted isreferred to as a picture in the followbe transmitted-to a light sensitive surface, 111g. It is however clearly understood that while successively applying voltage to the this term is always used in its broader meandifi'erent points of the projected picture. mg, which includes letters and tele ams.

Other objects will appear in the course Referring to the Figures 1-3 of t e drawof the specification and in the appended mgs, the Sending evice 11 consists of a l i s, main frame 12, in which two rolls 13 and Embodiments 'of my invention are shown 14 are journalled. These rolls carry an endin the accompanying drawings, in which less belt 15, which is positively fed by any 30 Fig. 1 is a schematic front view and secsuitable means. A picture to be transmitted tion of a sender constructed according to my. is fastened on belt 15 at 17 and moves then invention. slowly with the belt over stationary table Fig.2 is 'a side view, and partly a sec- 18 which is strongly illuminated. tion along linesA-A of Fig. 1. The illuminated picture is projected b 35 Fig. 3- is a section along lines BB of suitable means, such as a lens 20, to a be t Fi 1, and partly a view, lookin upwards. 21, which is. positively fed over a table 23 ig. iis a view of a modifiei detail of and two

rolls

24, 25. Belt 21 is provided a sender. on its outer side with a light sensitive sur- Fig. 5 to Fig. 8 are views of electric. conface or layer, which changes its electric con- 40 tacts, such as may be used in senders {nade ductivity under the influence of light. Vari-- according to my invention. t ous substances can be used for this pur- Fig. 9 and Fig. 10 are schematic outlines pose, one of which is selenium. of electric connections. On its downward side belt 21 moves in Fig. 11 is a front view and section of a opposite direction as compared with belt 15, 45 sender, illustrating a further embodiment of and with the same velocity as the projected my invention. picture,' w hoseoriginal moves with belt 15.

Fig. 12 is a side view, and a section along In other words, the

belts

15 and 21 are lines C-C of Fig. 11. timed up together and move with speeds ro- Fig. 13 is a diagrammatic view, illustratportional to the respective distances of t eir 50 ing the path of electric contacts and corpicture surfaces from lens 20. The prores onding to Fig. 11. jected picture is then relatively at rest with ig. 14 is a front view and section of a respect to belt 21. part of a receiving apparatus, which may A rotarycontact carrier 26 carries electric cooperate i. ith senders made according to my

contacts

27, 28, 29, arran equidistant 56 invention.

111 its axis 30, and dur ng its rotation lloj rier 26, an electric current will pass through a contact (27 in Fig. 1) and the point of the I light sensitive surface immediately under it; This electric current changes in intensity with the changing electric conductivity offered by .the dark and light points of said light sensitive surface, as a contact moves over them.

Although in the very moment of contact the contact member obscures theprojected picture around the point of contact, the op; eration is not impaired, because of the'time required by the light sensitive substance to change its resistance, that is to say because of the inertia of reaction. Thetime it would take to change the electric resistance by a substantial amount, is very much larger than the time of interference, for the contact carrier rotatesat high speed.

A lighted point of the projected picture is first under the influence of continuous light. Shortly before contact is made, .the projected light is split up -into rapid flashes by the relatively advancing rotating contact holders. The length of the flashes compares with the length of the interruptions, as the space between adjacent contact holders compares with the width of the contact holders.

(See FigR3.) Inasmuch as the width of the contact holders is small as compared with their distance from-one another, the average intensityof light at a considered point is only slightly reduced by the moving contacts. The inner side of belt 21 is preferably an electric conductor. Electric voltage may be applied to the inner side of said belt, or to table 23 over which said belt moves. This is schematically indicated by a wire 31 in contact with table 23. vAnother wire; 32 is in contact with carrier 26. It is understood that the parts under voltage are suitably insulated.-

Either direct current or alternating current may be used for application to the projected picture surface. In the latter case a current of high frequency is preferred. Contact carrier 26 is rotated by a shaft 35, a worm 36 and a worm wheel 37. Preferably rotation is efiected at high speed, A

while the motions of the belts'l5 and 21 are comparatively slow, usually a small fractionof an inch per revolution of said carrier'26.

Thecontacts

27, 28, 29 cover the picture surface 38 (see Fig. 3) along

successivev lines

39, 40, 41, which are substantially circular, arcs. Only points situated alon such lines will be transmitted, and for t is reason adjacentlinesshouldbe close enough to establish a coherent picture.

- It is noted that thearc ofcontact 42 is smaller than the are, for which two adjacent contacts (27, 28) are apart, so that not more than one contact is in action at every moment. 1 Q

The accuracy of the transmitted picture .may be increased byenlarging the projected picture, as compared withjhe original, as

indicated in Fig. 1 by a distance of belt 21' from lens 2.0, which is larger than the distance of belt 15 from lcns.2().v

When the contact carrier 26 is rotated. and

the

belts

15 and 21 are correspondingly fed, a projected pictiire moves past the path of the electric c( mt.-acts 27 8,29 and fluctuations in an elcectric cnrrnt are produced by the different electric c( iductivities offered'by the light and dark s1 ots of. the pro-- jection. I a

In the hitherto known senders which operate by projection of light, the various points of a picture are successively projected to a light sensitive cell. It is noted that according to my invention a whole picture area, or a whole picture, is simultaneously projected to a light sensitive surface, and voltage is successive] y applied to the diii'erent points of saidprojected area. In this way the inertia of the said surface, in adapting electric conductivity to the quantity of projected light, is eliminated, i. e. prevented from having any influence harmful to the.

light. When a contact moves over a point of the'light sensithe surface, the electric'conductivity. has been fully prepared, and im mediately the coordinate. amount of current will pass through.

The movements of the sender can there- 'fore be kept at high s eed. This is one of the essential factors w ich makes transmissionalso of telegrams possible. Anoth'er' lmportant'feature in this connection is the elimination of intermediate steps, as will be more fully'explained. i

A sender cooperates with 'a distant receiver, such as briefly outlined in Fig. 14. receiver contains a contact carrier 46, which corresponds to the contact carrier (26) of the sender, and whose contacts'l'l sweep over a tape orband 48, which is fed incorrespondence to belt 21 of Fig. 1.

Preferably the received picture is, kept full size. If .the projected picture of the sender is an enlargement, as shown in Fig. 1, the size of carrier '46, the width and the feed of band 48 are correspondingly reduced,

as compared with carrier 26 and belt 21.

. It is ob viousthat the rotary contact car? 'gular position of th an electric and table needs more amplification. V

rier 46 of the rece timed up with the the sender.

used in teleg iver must be wccurately rotary contact. carrier of Timing mechanisms have been raphy since scores of years, so that it is not deemed necessary to enlarge upon them,- especially since they are-not a part of the-present invention.

The

carriers

46 and 26 run with-the same angular velocities, and' any angular position of carrier 46 corresponds to an identical ane distant carrier 26. turn therefore as if con- In any moment and in The two carriers nected by a shaft.

any position of a cont-act, electricenergy is transmitted from the sender to the receiver in correspondence with the light or dark spots of the projected picture. This transmission may be made by wire or by wireless telegraphy. The energy impulses are suitably amplified in the receiving station, and are transmitted to the contacts '47, which imprint them to band 48 in an suitable way.

A way preferred for copying transmission of telegrams is to amplify the energy impulses and the voltage in such a way, that spark passes between contact 47 49, whenever a" dark point is to be marked on hand 48. A transmitted telegram appears then on band 48 without further steps.

It is immaterial, whether a dark point corresponds to an increased or to a decreased energy transmission, as long as the original is composed of lines or points. In the latter case a spark-immediatel follows a dark p0in't,-instead of being exact y simultaneous. v

Fig. 4indicates the use'of a prism 55 in addition to a lens 56. This makes possible to secure certain structural advantages. A picture 57 is projected to a light sensitive picture 58, which is angul-arly disposed to surface 57.

In the Figures 5 to 8, the

symbols

60, 61, 62, 63 denote a light sensitive surface; 64 denotes an electric contact with a sharp point; 65 indicates a contact with roundedpoint 66 is a contact with rounded point and separate core. The electric contact 67 isnot in physical touch with surface 63, but disposed at a certain small distance therefrom. It is well known that electricity may pass out of sharp points without actually touching a conductor. Contact 67 permits particularly high speed of the contact carrier (26), but its weaker primary current The fluctuating current obtained by suceessively applying voltage to the various points of a light sensitive surface are suitably amplified, a'nd are then either transmitted by wire way. I

In the diagram shown in Fig.9, voltage is obtained by an electric generator 70,

. tery 74 is connected with contact 75 .modifications ma What I claim is: or broadcasted in aknown nection with which produces either direct current or high frequency alternating current. rent passes through contact 71 and light sensitive surface 72, which together act in a way similar to a microphone. However, instead of sound waves, light and dark shades are transmitted.

The diagram indicated in Fig. 10 refers to direct current'only. One pole of a bat- ,and to the ground'76, if so desired. The other pole is connected ith light sensitive surface 77. Thev current fluctuations obtained in this circuitare amp d-in a relays 78, and transmitted to anothe' circuit 79.

It is understood that the rinciple of my invention is independent 0 electric con nectionsand combinations.

A further preferred embodiment of my invention is indicated in the Figures 11 to 13. The sender 85 contains a contact carrier 86. with radially and outwardly disposed electric contacts 87, which cooperate with a curved, and forms a part of a cylindrical surface, which is coaxial with shaft 89 of contact carrier 86. In the present embodiment, surface 88 is stationar and the contact carrier'(86 is fed in t e direction of its axis 89. whi e rotating. Voltage is applied betweensurface 88 and contact carrier 86 in any suitable way, such as indicated by two wires 90 and 9 touch with shaft 89.

Picture projection is effected in a novel way, inasmuch as the picture (92) is pro- 1, the latter being in 1 ected to acurved sending surface (88),

The curlight sensitive surface 88. Said surface is s also true original 92is kept on cylindrical surface 93 b suitable fastenin means, such as a curved glass plate 95, whic is laid upon the origmal 92 and prevents wrinkles.

i indicated in Figure 13, the light sensitive picturesurface or sending surface 88 is successively covered by contacts 87 along parallel lines 96.

that such changes and be made in my invention, elimits of the appended I It is understood as fall within t claims.

1. In a sender for picture transmission, in combination, 'a' light sensitive surface, an electric conductor in constant electric consaid surface, said surface and said conductor being relatively stationary,

means for projecting a picture to said surface, means for moving an electric contact adjacent said projected picture, and means for applying voltage between said contact and said conductor.

2. In a'scndcr for picture transmission, the combination of a light sensitive surface, means for projecting a pictureto said surface, a contact carrier containing a plurality of electric contacts arranged in a circle,

and means for successively moving said con-- tacts across said projected picture.

3.-In a sender for picture transmission, the combination of a light sensitive surface, an electric conductor in constant connection with said surface, means for projecting' a picture to said surface, a rotatable contact carrier containing a plurality ofelectric contacts equidistant flOIIl ltS axis,

means for rotatingsaid contacts in front of and ad acent said pro ected picture, and

means for establishing electric current by applying voltage to a contact and opposite 1 voltage to is 'd conductor.

4. In a se der for picture transmission, a

light sensitive" surface forming part of a concave cylindrical surface, and means for successively applying-voltage to different points of said surface. p

5.'In a sender for picture transmission, a

light sensitive surface forming part of a.

surface of revolution, an electric contact rotatable on an axis angularly disposed to the perpendiculars of said light sensitive surface, and means for rotating said con-- tact adjacent said light sensitive surface.-

6. In a sender for picture transmission, a curved lightsensitive surface forming part of a cylindrical surface, an original disposed on a curved surface, and means for projecting the original to the light sensitive surface. f

7. A method of sending pictures and the like, which consists in projecting a picture to a light sensitive surface, in providing a rotatable contact carrier having a plurality of contacts equidistant from its axis, said contacts being apart for distances larger than the active width of said picture surface, in rotating said contacts adjacent the fprojected picture, and in providing feeding ERNEST WILDHABER.