US1841540A - Method of recording electrical impulses for producing pictures and sound - Google Patents

Description

Jan. 19, 1932.

H. T. LEEMING METHOD OF RECORDING ELECTRICAL IMPULSES FDR YRODUCING PICTURES AND SOUND Filed May 51, 1928 I INVENTOR. Zbrry .Z 86/771 79 A TTORNE Y.

Patented Jan. 19, 1932 UNITED STATES PATENT OFFICE HARRY '1'. LEEMING, F JERSEY CITY, NEW JERSEY METHOD OF RECORDING ELmICAL IMPULSES FOR PRODUCING PICTURES AND SOUND Applieation flled Kay 31, 1928. Serial No. 281,959.

This invention relates to a method of re- I cording electrical impulses for reproducing pictures and sound and may be used as an intermediate stage for permanently record- '6 ing electrical impulses so that they may be this invention contemplates recording on a record of the phonograph type, electrical 1mpulses transmitted for the reproduction of pictures. From this record, by a reverse proc-. ess, these impulses are reproduced through suitable apparatus into the original. picture. On the same record impulses representing sound may be recorded and reproduced in synchronism with the picture impulses so that the picture and the sound associated therewith may be reproduced indefinitely as desired.

One method of transmitting picture's electrically is disclosed in U. S. Patent 1,656,915, January 24, 1928, and the present mventlon is applied with apparatus as disclosed in this patent, but it should be understood thatit may be applied to any system in which the transmitted vibrations are capable of being inscribed on a; record. In this patent the picture characteristics are transmltted as modulations of a carrier wave and are capable of being amplified and recorded on a phonograph record at the receiving station, in a manner similar to the recordin of radio impulses representing sound. pulses are mechanically recorded on a record it is apparent that this record permanently establishes a means whereby the same impulses may be reproduced and the record itself can easily be duplicated and distributed, thus by a comparatively simple mechanism the received impulses can be retranslated into the original picture and sound as often as desired.

In the drawings, Fig. 1, shows the transmitting station and the receiving station with the recording record and Fig. 2 shows an arrangement for reproducing the original effects from the record.

The cylinder 11 carrying the transparency 13 is rotated by shaft12 and through the bevel gears 54 and rotates the sectored en th'ese im.

disc 15 known as a scanning disc in synchronism therewith. The photo electric cell 16 responds to the light from the source 14 as modified by the sectored disc 15 and the transparency 13. Through the circuit 17 this cell controls the modulating device 18 operated by the source of energy 19 and transmits the modulated effect through 20 to the demodulator 21 and through the circuit 22 to the stylus head 23 engaging the record 24.- which is rotated at a predetermined speed having a definite relation to the speed of shaft. 12. i

It is apparentthat in the arrangement described the stylus head, which is of the type known as the electric pick up, responds to the light variations afl'ecting thephoto electric cell 16 and which include the p'ictureon the transparency 13. Thus the groove of the record 24 is inscribed with undulations corresponding to the electrical variations produced by the picture at the transmitting station.

An elementary form of sound transmission is indicated by the microphone 25 inductively coupled with the antennae 27 at 26 and received by the antennae 28 which is inductively coupled at 29 with the amplifier 30 and through the transformer 31 and circuit 32 operates the electric pick up stylus 33 33 will inscribe a groove on the record cor-' responding to the sound impulses produced at'25. The stylus heads 23 and 33 record on the record at the same time and may be arranged to operate in parallel spiral grooves on the face of the record, however, it is well known'that two different sets of undulations can be cut in thesame record groove without confusion, for instance the sound undulations may use the side out and the light undulations may be recorded on the bottom of the groove, that is the hill and dale out.

In Fig. 2 the electric pick up head 41 is arranged to respond to the undulations in the record 24 produced by the photo electric cell 16 which, through the transformer 42,

amplifier 43 and circuit 44 controls the light valve 45 and the illumination from the source 46 projecting through the sectored disc 47 on the screen or film 48. The turntable for the record 24 is driven by shaft 56 at the same speed as was used when recording so that the impulses picked up by 41 correspond in frequency with the impulses from the transmitting station. By the bevel gears 57 and 58 and the shaft 59, the sectored disc 47 is rotated at the same speed, or at a speed corresponding with the speed of the sectored disc 15 at the transmitting station.

It will be noted that while the discs 15 and 47 do not rotate at the same time, there is nevertheless a definite relation established between their rotation whereby the light impulses passing through 15 also pass through the sectors of 47 as reestablished by the record 24. These impulses are modulated by the picture 13 which is transferred to the record and from the record correspondingly reproduced in the projected picture on the screen 48.

The electric pick up head 49 engages the sound producing groove and through the, transformer 50, amplifier 51 and circuit 52 operates the loud speaker 53, thus producing sound as received from the transmitting station in synchronism with the picture display, or independently of the picture projection.

In order to record and reproduce vibrations of a frequency suitable for translating into pictures, I prefer to use metallic records of the type disclosed in U. S. Patent 1,421,045, June 27, 1922, which may be used in the form of a disc or in the form of a ribbon. The metallic record is close in the grain and will register high frequency vibrations. Its speed can be accelerated for the same pur pose and it is easily duplicated.

Having thus described my invention, I claim:

1. A system for transmitting, recording and reproducing picture effect-s, comprising a picture, a source of illumination for the picture, a rotating scanning disc controlling the illumination from said source, a light sensitive cell, subject to said illumination, a

transmission circuit controlled by said cell,

a receiving circuit connected with said trans mission circuit, a magnetic pick-up with a stylus connected with said receiving circuit, a rotating record mechanically inscribed by said stylus according to the impulses in said transmission circuit, a drive shaft for said record, a reproducing stylus in a magnetic pick-up head, engaging the inscribed grooves of said record, a reproducing circuit connected with said reproducing head, a light valve controlled by said reproducing circuit and controlling a source of light, a second scanning disc gear connected with said drive shaft and a screen upon which said light is projected, said second scanning disc intercepting the projected light beam.

2. A system for transmitting, recording and reproducing picture effects, com rising a picture, a source of illumination or the picture, a rotating scanning disc controlling the illumination from said source, a light sensitive cell, subject to said illumination, 9. transmission circuit controlled by said cell, a receiving circuit connected with said transmission circuit, a magnetic pick-up with a stylus connected with said receiving circuit, a rotating record mechanically inscribed by said stylus according to the impulses in said transmission circuit, a drive shaft for rotating said record, a reproducing stylus in a magnetic pick-up head, engaging the inscribed grooves of said record, a reproducing circuit. connected with said reproducing head, a light valve controlled by said reproducing circuit and controlling a source of light, a second scanning disc gear connected with said drive shaft controlling said source of light and a screen upon which the picture is projected.

3. A system for recording and reproducing picture efi'ects, comprising a disc shaped record having inscribed thereon, grooves with undulations corresponding to the picture effects, a drive shaft for rotating said record, a reproducing stylus and a magnetic pick-up head engaging said grooves, a reproducing circuit connected with said reproducing head, an amplifier in said circuit, a light valve controlled by said reproducing circuit and controlling a source of light, a scanning disc controlling said source of light gear connected with said drive shaft and means for, projecting the light from said source, upon a screen.

In testimony whereof I aifix my signature.

HARRY T. LEEMING.

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