公开(公告)号：GB515843A

公开(公告)日：1939-12-15

申请号：GB1750738

申请日：1938-06-13

Applicant: BAIRD TELEVISION LTD ,  THOMAS CAYTON NUTTALL

IPC: G05B5/01 ,  H03H7/01 ,  H03H7/06 ,  H03L7/093

Abstract: 515,843. Television. BAIRD TELEVISION, Ltd., and NUTTALL, T. C. June 13, 1938, No. 17507. Drawings to Specification. [Class 40 (iii)] [Also in Group XXXV] The deviations of a variable frequency current from a standard frequency current are corrected by applying both to a detector whose output is a measure of the deviation, and applying the output to correct the variable frequency. According to the invention,. the output is applied through a low-pass filter so as to prevent fluctuations above a predetermined frequency in the standard frequency having much effect on the correction, and the filter produces a phase advance which is a maximum near the limiting frequency to prevent instability. Suitable filters are shown in Figs. 6, 9 ... 16 (not shown). The invention is applied to television (in which the variable frequency current is the scanning oscillator and the standard-frequency current is a mains supply), and to gramophones (in which the variable frequency current is derived from the turntable). The variable frequency may be derived from an oscillator whose frequency is determined by a condenser varied by an electromagnetic system under the control of a dash-pot.

公开(公告)号：GB515800A

公开(公告)日：1939-12-14

申请号：GB1750838

申请日：1938-06-13

Applicant: BAIRD TELEVISION LTD ,  CYRIL EDMUND MAITLAND

IPC: H03F1/50 ,  H03H7/01

Abstract: 515,800. Valve amplifying circuits. BAIRD TELEVISION, Ltd., and MAITLAND, C. E. June 13, 1938, No. 17508. [Class 40 (v)] An intervalve coupling arrangement for very high frequencies comprises the inductance 2 of a tuned circuit and a resistance 3 connected between the anode of the first valve 1 and the high-tension source, the junction of the elements 2, 3 being connected through a lowreactance condenser 4 and an inductance 5 to earth, and the junction of elements 4, 5 being connected through an inductance 6 to the grid of the second valve 7. The inductances 2, 6 may be tuned by the inherent inter-electrode capacities 8, 9 of the valves 1, 7, respectively. Damping resistances may be added in series or shunt to the tuned circuits 2, 6 and the inductance 5 to give a wide pass-band of uniform response.

公开(公告)号：GB514271A

公开(公告)日：1939-11-03

申请号：GB1281138

申请日：1938-04-29

Applicant: BAIRD TELEVISION LTD ,  THOMAS CAYTON NUTTALL

IPC: H04N5/10

Abstract: 514,271. Television receivers. BAIRD TELEVISION, Ltd., and NUTTALL, T. C. April 29, 1938, No. 12811. [Class 40 (iii)] Both sets of synchronizing impulses are applied to the input terminals 11 of an unterminated artificial transmission line 6, Fig. 2, so that reflection occurs and signals reappear at its input terminals after a period equal to twice its delay time, the combined original and delayed signals being applied to an amplitude filter 5 which passes only signals exceeding the amplitude of the individual signals. The delay time is such that the lower-frequency long-duration pulses overlap and thus increase in amplitude while the high-frequency short-duration pulses do not. The artificial transmission line may be a four-terminal network, Fig. 3, comprising at least one inductance 12 and two condensers 13, 14 producing at least one finite frequency of zero reactance and one finite frequency of infinite reactance. Specification 491,728 is referred to.

公开(公告)号：GB514270A

公开(公告)日：1939-11-03

申请号：GB1281038

申请日：1938-04-29

Applicant: BAIRD TELEVISION LTD ,  ALEXANDER KONSTANTINOVICH DENI

IPC: H01J31/12

Abstract: 514,270. Cathode-ray tubes. BAIRD TELEVISION, Ltd., and DENISOFF, A. K. April 29, 1938, No. 12810. [Class 39 (i)] In television &c. receivers with a modulated scanning cathode ray to produce the visual image, the ray sets up a slowly-decaying secondary electron beam at the fluorescent screen so that the light persists at each point after the scanning ray has passed on to other points. The modulated ray from the gun 2 scans the fluorescent screen 5 and secondary electrons from the screen are accelerated by a grid 4 and retarded by a grid 3 to return to the screen 5 to produce more secondary emission. High-frequency oscillations are supplied between the screen 5 and grid 4 so that the arrangement acts as a to-and-fro electron multiplier with magnetic focusing 6 and with the secondary emission dying down in one frame period. The gauzes 3, 4 are of wire of diameter one-tenth of that of the ray from the gun 2 and have a mesh ten times this ray diameter. A screen giving a suitable rate of decay of the beam may be made by adding beryllium hydroxide and caesium to ordinary fluorescent components.

公开(公告)号：GB513628A

公开(公告)日：1939-10-18

申请号：GB180538

申请日：1938-01-19

Applicant: BAIRD TELEVISION LTD ,  VICTOR ANGEL JONES

IPC: H01J29/43

公开(公告)号：GB509758A

公开(公告)日：1939-07-17

申请号：GB3149037

申请日：1937-11-16

Applicant: BAIRD TELEVISION LTD ,  JOHN LOGIE BAIRD

IPC: G03B41/08

Abstract: 509,758. Kinematograph apparatus. BAIRD TELEVISION, Ltd., and BAIRD, J. L. Nov. 16, 1937, No. 31490. [Class 97 (i)] In intermittent-feed apparatus comprising an optical compensator operative during the feed movements, the compensator comprises an oscillating light refracting device which is withdrawn from the light path while the film is stationary; the compensator may be a block of glass or synthetic resin and may be replaced in the beam by a non-oscillating block while the film is stationary. As shown, the compensator in a projector comprises a block 7, and a second oscillating block 6 displaces the light beam falling on the film 4 from a source 1. The blocks 6, 7 rock simultaneously in opposite directions, are removed from the beam when the feed claw disengages the film, being there replaced by non-oscillatory blocks, are rocked to their original positions, and are again moved into the beam when the feed claw re-engages the film A condenser 2 focuses light from the source 1 on an aperture 3, and a lens 5 focuses an image of this aperture on the film.

公开(公告)号：GB507165A

公开(公告)日：1939-06-12

申请号：GB3419937

申请日：1937-12-10

Applicant: BAIRD TELEVISION LTD ,  JOHN LOGIE BAIRD

IPC: G03B41/04

Abstract: 507,165. Kinematograph apparatus. BAIRD TELEVISION, Ltd., and BAIRD, J. L. Dec. 10, 1937, No. 34199. [Class 97 (i)] In apparatus in which a continuously or intermittently moving film is continuously projected or exposed by means of two optical systems alternately brought into use, a mirror which moves into the optical path between one of these systems and a third system continuously in use, has a strip adjoining its leading edge rendered non-reflecting, so that it does not begin to reflect light to one system until it also cuts off light from the other system. As shown, the image 1 on an intermittentlyfed film in a two-image gate is projected, while the film is stationary, by a fixed lens 4 and a, fixed lens 3. While the film is being fed upwardly, the image 2 on the film is projected by a moving, compensating lens 5 and the lens 3, light being reflected between the lenses by a fixed reflector 6 and a mirror 7 which moves into ,position, prior to the film movement, from a position 8. The part 9, 10 of the mirror is blackened, to prevent reflection of the beam from the image 2 until the edge 10 of the mirror begins to cut off the beam from the image 1.

公开(公告)号：GB498824A

公开(公告)日：1939-01-13

申请号：GB1933737

申请日：1937-07-13

Applicant: BAIRD TELEVISION LTD ,  PETER WILLIAM WILLANS

IPC: H01J31/12 ,  H01J31/18

Abstract: 498,824. Cathode-ray tubes. BAIRD TELEVISION, Ltd., and WILLANS, P. W. July 13, 1937, No. 19337. Drawings to Specification. [Class 39 (i)] In a television receiving-device in which an electrostatic image corresponding with received signals is formed on a control electrode to control the spatial distribution of an electron stream, as described in Specification 475,047, the control electrode consists of a conducting grid coated with an insulating substance which is capable of emitting secondary electrons, or carries secondarily emissive mosaic elements, and is scanned with an unmodulated electron beam while signal potentials are simultaneously and synchronously applied to the grid, so that the portions of the control electrode surface being scanned attain, relative to the external electrodes, a constant instantaneous potential and, relative to the grid, potentials varying in conformity with the electrostatic image it is desired to reconstitute ; during the flyback periods the scanning beam is switched off and the grid brought to a fixed potential, being meanwhile flooded with an electron beam which, modulated in its different parts by the control grid, is focused on to a fluorescent screen. The flooding-beam is switched off except during the flyback periods.

公开(公告)号：GB494586A

公开(公告)日：1938-10-27

申请号：GB1201537

申请日：1937-04-27

Applicant: BAIRD TELEVISION LTD ,  GEORGE RICHARD TINGLEY

IPC: H01J29/76

Abstract: 494,586. Discharge apparatus. BAIRD TELEVISION, Ltd., and TINGLEY, G. R. April 27, 1937, No. 12015. [Class 39 (i)] Magnetic deflecting means for an electrondischarge device such as a cathode-ray tube comprise a U - shaped ferromagnetic yoke 1, Fig. 2, the limbs of which embrace the tube 4 and are provided with substantially semi-cylindrical polepieces 3 the length of which in the direction of the electron beam is substantially greater than that of the yoke, and the dimensions of the polepieces are such that they form an almost closed cylinder round the tube ; coils 2 and 5 are provided on the yoke and within the polepieces for producing components of the deflecting field at right-angles to one another. Extensions to form a gapped or closed iron circuit may be provided on the core to increase the inductance of the coil 2. In a modification, Fig. 1, the polepieces 3 are displaced from the yoke 1 towards the source of electrons and are connected to the yoke by ferromagnetic strips 7. The yoke also may be provided with small extrusions 8 embracing the tube 4 and with extensions 9 having adjustable polepieces as described in Specification 462,684. This modification is stated to give a better correction of the " pincushion " distortion and prevents barrel distortion while reducing the interaction between the scanning fields.

公开(公告)号：GB491886A

公开(公告)日：1938-09-12

申请号：GB729937

申请日：1937-03-12

Applicant: BAIRD TELEVISION LTD ,  ALFRED HENRY GILBERT

IPC: H04N5/64

Abstract: 491,886. Television receivers. BAIRD TELEVISION, Ltd., and GILBERT, A. H. March 12, 1937, No. 7299. [Class 40 (iii)] Translucent material 3, such as ground glass, is used to obscure the detail in those parts of the image falling on the sharply curved areas of the fluorescent screen 1, without reducing the light emitted. Light lost in transmission through the glass may be compensated by mirrors behind the glass.