US1978288A - Television apparatus - Google Patents

Description

Oct. 23, 1934. D. E. WORLIITZ TELEVI S I ON APPARATUS Filed Sept. 21, 1931 2 Sheets-Sheet l 5p Z9 MENTOR W ATTORNEY Oct. 23, 1934. D, E. WORLITZ TELEVISION APPARATUS s hm QM mwnN INVENTOR W V ATTORNEY Patented Got. 23, 193

TELEVISION APPARATUS Daniel E. Worlitz, Anamoose, N. Dak. 7 Application September 21, 1931, Serial No. 564,086

3 Claims.

My invention relates to one-way television apparatus for transmitting and receiving images of pictures, natural scenes, or cinematograph piotures (the images to be transmitted may be either modulating a broadcast carrier wave, or by means of apair of suitable electrical conductors, and it consists in the combinations, constructions and arrangements herein described and claimed.

An object of myinvention is to provide a means for transmitting and receiving black and. white images of stationary or moving objects over one broadcast carrier wave, or over one pair of electrical conductors. I

Another object is to provide a simple new method of mechanical television scanning, which gives much greater illuminating efficiencies than conventional scanners, by. means of two opaque magnetizable needle springs vibrating at different assignable speeds and at right angles to each other so as to scan the light going through the scanning frames of the transmitter and receiver. The different relative speeds (which determine the picture scanning detail) assignable, are limited only by the mechanical vibrating abilities of the springs used.

Another object is to provide a new means of synchronizing the receiver set scanner springs with the corresponding springs of the transmit- .ter set. V

.A further object of my invention is to provide a compact device of the type described consisting of parts readily obtainable and which, therefore, can be assembled at a relatively low cost.

other objects and advantages will appear in the following specification, and the novel features of the invention will be particularly pointed out in the appended claims.

My invention is illustrated in the accompanying drawings, forming a part of this application, in which Figure 1 is a diagrammatic view of the transmitting apparatus. 1

, Figure 2 is a section on the line 2 2 of Figure 1. Figure 3 is a front elevation.

Figure 4 is a view of the receiving apparatus.

Figure 5 is a section on the line. 5-5 of Figure 4. i

As stated above, in carrying out my invention, Imake use of standard equipment, such as that used in radio to a large extent. These parts, for the sake of clearness, I have illustrated diagrammatically, since it will be understood that any apparatus suitable for the purpose may be used, the invention lying in the general arrangestationary or in motion) electrically, either by scanning frame opening 3 l1. are two somewhat needle-like springsor spring 1 (c1. firs-4s ment and not in the particular parts, except as regards the receiver and transmitter scanners, which scanners and their different arrangements are shown in detail. i

In carrying out my invention, I. provide a transmitte'r which consists of a rectangular box 10,

having at one end a suitably sized and shaped Within this box armatures 12 and 13 suppo'rted by means of re- 55 spective pairs of posts 14 and 15, and 16 and 17, in such manner that the free ends thereof formed as segments 18 and 19 are at right angles and are free to vibrate at right angles with respect a 'to each other behind the picture frame or opening 11, in a direction parallel to the frame. If the picture frame is made either square or oblong shaped, then the spring armatures should be so adjusted upon their supports that the right-angularly disposed segments vibrating past each other behind the frame 11 will have the centers of their planes of vibration apparently intersecting each other in the center. of the frame, as viewed from the front. One spring armature segment should scan the picture frame from left to right parallel to the vertical sidesof the frame, and the segment of theother vibrating spring armature should scan the frame from top to bottom parallel to the horizontal sides of the frame, and return and repeat continuously. In order to adjust the spring armatures so that they may be able to vibrate at their assigned frequencies, the lengths of the supported ends of thesprings are made variable by means of adjustable set-screws 20 and locknuts 21 which hold the springs securely to their respective posts. In order to permit better quality scanning, the scanning segments of the ends of the armatures or springs may be curved to an arc of a suitable radius so that they can pass each other closely and still stay at a uniform distance from each other while scanning the frame.

The armatures 12 and 13 are of course opaque and of magnetic material and are kept vibrating at their assigned frequencies by means of suitable electromagnets 22 and 23, respectively, properly placed and fastened to the inside of the box or casing 10. The electro-magnets are actuated by either alternating or interrupteddirect current at the frequencies assigned to their respective armatures, by their respective suitable oscillators 24 and 25, or any other suitable source ,of electricity. 1

All of the surface of the object 26, except that which is held back by the armatures 12 and 13 while scanning, is illuminated by a suitable source 27 of steady light (such as an are light) passing through an opening 28 and the opening 11 which are located centrally on the rear and front of the casing 10 respectively. The lamp 27 is suitably mounted and housed in a light-proof and heat ventilated box 29 attached to the rear of the light-tight box 10. Any suitable source of electricity (which should be steady) can be used to operate the are light.

Any desired number of suitable photo-electric cells 30 may be suitably placed around the front of the frame 11, so that they can clearly see or be affected by the illuminated object 26 whose image is to be transmitted.

In operation the transmitter shown in Figures 1 to 3 will function as follows:

It is to be understood that the spring armatures 12 and 13 can be made to vibrate at any assignable relative speeds to one another at which it is physically possible for them to vibrate. Since the relative speeds assigned to the springs determine the fineness in the detail of the transmitted and the received television image, it is convenient for the sake of illustration, to use the conventional standard picture detail of fifteen pictures and forty eight scanning lines per second. One

of the spring armatures must be made to vibrate "at a frequency rate of seven and one half to determine the pictures per second, and the other at a'frequency rate of seven and one half times twenty four to determine the scanning lines per second, in order to produce the conventional standard. The right angled portions 18 and 19 of the spring armatures which scan the frame. opening 11 should be of the same diameter and be made approximately one sixteenth of an inch in diameter. Now, if we let one of the armatures,

vibrating 'from'left to right, or vice versa, (at a frequency rate'of seven and one half vibrations per second) represent the scanned pictures per second, then we can let the other, vibrating from topto bottom, or vice versa, (at a'frequency rate of sevenand one half times twenty four vibrations per second) represent the scanning lines per second. Now as the first spring armature travels across the opening 11 fromleft to right (as viewed from'the-front of the frame) the second or scanning-line armature traversing the frame or opening I1 from'the top apparently intersects the first armature segment but travels its course downward at a rate forty eight times faster. The apparently continuous trace of intersection of the two opaque spring armatures begins in the upper'left corner of the frame and forms a straight line downward to the right at a definite angle which is determined by the relative vibration speeds of the two armatures. Since the area of steady light shining through the frame from light source 2'7 illuminating the object 26 never changes, and sincethe combined area of the two intersecting armature segments scanning the frame also never changes, the definite area of shadow formed by the trace of intersection thrown upon a portion of the object actually determines the point of the object being scanned. As the area of intersection traces a shadow over the object'261ight and dark portions of the object will be rapidly scanned. As the shadow trace of the intersecting spring armatures scans a dark portion of the object, the total light reflected from thewhole object 26 to the photo-electric cells 30 is decreased in proportion to the darkness of the portion covered by the shadow. When a lighter part of the object is covered by the shadow, the

total light reflected to the photo-electric cells 30 will be less intense than previously, directly in proportion to the now decreased reflecting qualities of the object as a whole. On its return the scanning line spring armature reverses its motion and moves from bottom to top and again intersects the slower moving spring armature but this time forms a trace upward and at a definite angle to the right from its starting point. The scanning spring armature continuously and successively repeats this action until the first armature has completely traversed the picture frame from left to right. When the first spring armature scans the frame during its return motion the whole foregoing process is repeated in the reverse manner, this determining the second picture. Thereafter, this foregoing cycle repeats itself continuously as long as may be desired.

The varying electric currents produced in the photo-electric cells circuit by the varying total light reflected from the object to the photo-electric cells are amplified by any suitable amplifier 31 and broadcast over an ordinary broadcast station 32 by means of aerial 33 and ground 34.

At the television receiver, Figures 4 and 5, the

ordinary broadcast receiver 35 is tuned to the carrier wave of broadcast station 32. Now the television signal received by the receiver 35 over aerial 36 and ground 3'7 is amplified by amplifier 38 and made to vary a neon lamp 39 which is set behind scanner spring armatures 40 and 41 similar to those shown at 12 and 13 supported upon posts 42 and 43 and 44 and 45, and inclosed in a light-tight box 46. One of the springs is adjusted to vibrate so as to scan the frame 47 from left to right at a frequency of seven and one half vibrations, to determine the pictures per second, and the other spring from top to bottom at a frequency of seven and-one half times twenty four vibrations per second, to determine the scanning lines per second. Each of these springs is'kept vibrating in synchronism with the corresponding springs of the transmitter by means of the electro-magnets 48 and 49. Every time the scanning line spring passes across the picture frame at the transmitter, periodic light reflections are impressed upon the photo-electric cells which in turn are automatically impressed upon the natural television signal. Similarly, every time the picture spring passes before the frame 11, a periodic current impulse is impressed upon the tele vision signal. These periodic current impulses are filtered out of the received signal and made to actuate the corresponding electro-magnets by picture image in the exactlight and dark shade values corresponding to those of the object 26. Every'time the picture spring crosses the picture frame a new picture will have been transmitted and reproduced upon the screen 52 at the receiver. These whole picture images are successively and continuously reproduced as long as may be desired. A person actually walking across a stage may have his image transmitted and thrown upon a screen and the movements of the person will be followed faithfully by the movements of the image on the screen.

It is understood that instead of viewing the received television image upon the screen, it may also 1 be viewed directly in the receiver ,frame 47.

the picture 26 and'focused upon the photoelectric cells 30. ,The photoelectric cells 30 in this case: are placed behind the film instead of in front of the object as ordinarily.

When it is desirable to project the received television image upon "a standard sized movie screen, the television signal may be made to modulate an Alexanderson-Karolus light valve instead of the neon lamp 39. In this case, the steady arc light 53, (which is suitably placed and housed in a heat ventilated box 54) is shown through box 46, by means of opening 55, Alexanderson-Karolus light valve (replacing lamp 39) and the scanning frame opening 47, and focused upona suitable movie screen. It is understood that the are light 53 may be disconnected when the neon lamp 39 is used instead and in place of the Alexanderson-Karolus light valve.

The steady are light 53 (located as shown in the drawing Figure 4) can also be modulated so as to serve as a speaking arc, by impressing the received and amplified television signal upon it in the conventional manner. The speaking arc, in this case, can be used instead and in place of the neon lamp or the Alexanderson-Karolus light valve system.

It is understood that the above method of scanning at the transmitter is comparable to the conventional spot-light system of scanning, in which the object is illuminated by the light shining upon the object through the scanning frame. Good scanning may also be obtained with this transmitter by using the conventional flood-light system of illuminating the object. To use the flood-light system of scanning with the transmitter Figure 1, in preference to the spot-light system as described above, the photo-electric cells 30 should be compactly placed inside of box behind the scanning segments of the springs 12 and 13 so that they can properly see the object to be scanned through the frame 11. The light 27 may be turned out or removed entirely. In this case, the opening 28 should be sealed against light. The object in this case should then be sufficiently illuminated to properly actuate the photo-electric cells by throwing suitable steady light upon it. When cinematograph picture images are to be transmitted, light 27 should be placed behind the film so as to project through the film, through the frame 11 and upon the photoelectric cells behind the scanner. In the flood-light system the image of the object 26 projected upon the photo-electric cells is successively scanned by the shadow trace of intersecting scanning needles 12 and 13. Therefore, in the flood-light system, the various light effects upon the photo-electric cells 30 is in every sense proportionally equal to that produced by the spot-light system of scanning.

The electrical connections of the photo-electric cells need not be altered to be used in the flood-light system and any suitable hookup may be used.

Whereit is practical and. convenient, step-up or step-down oscillators, Whichare connected to suitable amplifiers, can be used to synchronize the springs of the receiver Figure 4gwith those of Figure 1, in the following manner:

.Eitherone of the springs vibrating frequencies of the transmitter can be filtered'out of the re ceived television signal, at the receiver, and suitably amplified toelectromagnetically vibrate the corresponding spring of the receiver, and at the same time, this filtered frequency can be made to act as a master oscillator to operate a step-down or astep-up oscillator to produce the second fre quency required to electromagnetically vibrate, after being sufiiciently amplified, the other spring at the required frequency.

While I have shown-a means for transmitting images of objects by wireless, it will be understood that they can be transmitted by means of wires. In such instance, the amplified current might be run directly through the lamp of the receiving instrument by means of suitable conductors, or if the distance be too great, relays or other amplifiers might be used without departing from the spirit of the invention. Instead of projecting the image upon the screen, it might, of

course, be projected upon a sensitized plate in the case of a stationary object, or it might be projected upon a movable film to form a basis for moving picture projection.

While I have described and illustrated one method of arranging opaque magnetic needle spring armatures for scanning, other arrangements may be made in which two opaque magneticneedle springs scan in a similar manner to that described above. Notwithstanding the fact that there are several other methods of arrangement, the basic method of scanning the frame by means of two intersecting opaque magnetic needle springs remains the same.

It is understood that wherever it is found necessary suitable lenses may be inserted into any or all of the above light beams, in accordance to well known practices.

I claim:

1. An apparatus for transmitting images of objects comprising a transmitter casing having a scanning frame opening at the front end and an aperture at the rear end through which a light at the rear of the said transmitter casing illuminates the object, two opaque magnetic armatures supported at one end and having free scanning ends of a uniform diameter at right angles to their supported ends, each armature having supporting posts with means for adjusting the length of the armature which they support, said 1 armatures being adapted to vibrate whereby their scanning ends will have the centers of their planes of vibration closely behind the center of the scanning frame opening, said scanning ends being of a comparatively narrow width to limit the shadow cast to an elemental picture area, electro-magnets energized by varying current to vibrate the armatures, photo-electric cells which read and translate the varying total light valves reflected from the object being scanned into electrical variations, and an amplifier to amplify these varying photo-electric cells current, so as to be able to broadcast them over an ordinary radio broadcast carrier wave.

2. In a television apparatus embodying a source of light and an object whose image is to be transmitted at the transmitting station, a scanning means comprising electro-magnetically operated armatures mounted for vibration at different respective speeds and having portions intersecting between the source of light and the object for scanning the latter with a shadow, said intersecting portions being of comparatively narrow Width, so that the shadow cast is that of an elemental picture area, means for adjusting the effective length of the armatures, a receiving station embodying similar armatures mounted for corresponding vibration at respectively proadmitting opening, and a pair of electro-magnetically operated vibratory reeds mounted within said supporting structure, each of said reeds comprising an elongated L-shaped member, a pair of upstanding posts through which each reed is slidable, adjusting means carried by each reed and cooperating with one of the posts for varying the effective length of the reed, and means carried by the other post of each pair and engaging the reed passing therethrough, said reeds being arranged with their laterally deflected ends in overlapping or intersecting relation behind said opening and said ends being of a comparatively narrow width, so that the shadow provided b is that of an elemental picture area.

DANLEL E. WORLITZ.

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