SU44700A1 - Interferometer - Google Patents

Description

The invention comprises an interferometer, the mobile optical system of which, in order to bring it into oscillation by alternating current, is connected directly to one of the plates of a capacitor fed by an alternating current, or to a coil placed in a magnetic field and fed by an alternating current.

In devices for recording on a photo tape of alternating current of different frequency, intermittent current or individual pulses, it is possible to use interferometers, i.e., glass systems in contact, 5, or not in contact, arranged in parallel or at some angle, spherical, flat or some other forms (for example, cylindrical, etc.), of which one part can be fixed motionless, while the other is mechanically connected to the source of vibrations. The interference figures produced in such a position of the glasses change their location, type and shape, depending on the vibrations caused by the sound, directly or converted into electric current. Impulses can be not only sound vibrations transformed into current, but II any others (light, heat, etc.).

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The operation of the device proceeds as follows. Vibrations required for recording are converted, for example, into electrical pulses, the latter being driven by one of the glass systems with a certain frequency and amplitude of oscillations. If one of the glass systems with a reduced frequency is oscillated, then Newton's rings (bands or other interference figures) will move with a frequency equal to the frequency of the oscillations introduced and with an amplitude corresponding to the amplitude of these oscillations. The optical system is designed so that in the absence of vibrations on the recording device, for example, on film, plate, photocell and the like, the light does not fall, or vice versa, the full luminous flux falls.

The working area will go from dark to light or vice versa, with the frequency of the input oscillations, and the degree of illumination at each moment will correspond to the amplitude of the applied oscillations.

By means of a screen with an optical slit (with one or several connected in parallel) from the area occupied by the interference figures, such a part is selected, in which the incident on the recording device

The rays fix the curves, the amplitude of which corresponds to the strength of the sounds being uttered, and the frequency to the frequency of the sound.

Recording the resulting curves is performed in one of the usual ways, for example, on a moving tape, etc. The sounds from the resulting recording are also reproduced in the usual way. In order to increase the amount of light incident on the recording device, it is advisable to use a central interference zone, for example, the central spot of Newton's rings.

In such devices, it is possible to use an interferometer in which one of the glass systems is mechanically coupled with a metal plate of an electrostatic loudspeaker, driven by an electromotive force, excited by one of the known methods of sound being recorded.

For the same purpose, an interferometer can be used in which one of the interferometer systems is connected to a coil placed in a constant magnetic field and powered by an audio frequency current.

Finally, it is possible to use an interferometer in which one of the interferometer systems is rigidly connected to a closed coil placed in an alternating magnetic field.

Such interferometers, coupled with a special timer, make it possible to determine the depth of the channel. For this, the sounds reflected from the bottom should get

on the interferometer, and the time interval between the sending of sounds by the generator and their reception on the interferometer must be determined.

The determination of the time interval can be obtained automatically if the interferometer is positioned so that when the sounds are sent by the generator, the interference patterns change. In this case, using a photocell, you can get two current pulses, one of which will correspond to the moment of sound sending, and the other - to receive sound.

The interferometer can also be used in azroplan detection devices, i.e., in sound detectors. For this, a highly sensitive interferometer is installed in the secondary focus of any horn or acoustic mirror and the like of a sound pickup device, one of whose systems is driven by sound coming into the horn.

The interferometer does not have a mechanical connection with the horn, in order to avoid the harmful effects of the mechanical oscillations of the horn itself, for example, from wind, jolt, etc.

The subject matter of the invention.

An interferometer, characterized in that its movable system, in order to bring it into oscillation by alternating current, is connected directly to one of the plates of a capacitor fed by an alternating current, or to a coil placed in a magnetic field and fed by an alternating current.