SU382984A1 - EU ^ - Google Patents

Description

one

The invention relates to the field of accurate distance measurement, namely to range finders, based on the measurement of the propagation time of electromagnetic radiation, in particular light, between the ends of a determined distance.

Electro-optical range finders are known, which contain a source of electromagnetic radiation, directed after modulation along the measured line, and a receiver that perceives reflected radiation and generates a signal transmitted via a feedback circuit to modulate the radiation. The frequency of self-excited modulation is measured and serves as a measure of the measured distance.

In the known electro-optical range finders of this type, as well as in phase range finders in general, the indication of the results of measurements in digital form is associated with considerable difficulties and, first of all, with the complication of the electronic circuit of the range finders.

To simplify the direct indication of the measurement results in digital form, mixers connected to a common generator of sinusoidal oscillations are included in the feedback circuit behind the radiation receiver and in front of the amplifier at the input of the modulator to reduce and correspondingly reverse the frequency of the pulses taken from

receiver. Between these mixers, at an adjustable, measurable distance, from one another are placed an electrical impulse transducer into a traveling wave with a length corresponding to a lower impulse frequency, and an inverse transform analyzer. The magnitude of the adjustable gap now serves as a measure of the measured distance, convenient for displaying in digital form.

FIG. 1 is a block diagram of the proposed rangefinder; in fig. 2 - the expedient form of constructing an adjustable measurable gap by means of mixers.

The light source 1 is located at the focus of the condenser 2, behind which a collecting lens is placed 5. Emitted by a light source of diverging light rays 4 after condenser 2, in the form of a beam of parallel rays a modulator 5 is placed between the condenser and the collecting lens, modulating this light sinusoidal voltage. The lens of the transmitter 6, having a common focus 7 with the collecting lens, directs a beam of parallel light beams 8 to the remote reflector 9 at the end of the measured distance.

The light beam 8, reflected from the remote reflector 9, hits the objective lens 10 of the receiver, the optical axis O-O of which is mainly parallel to the optical axis 0 - the objective lens 10 is at the same distance from the reflector 9 as the lens 6 and in the focal whose plane or close to it is placed the photoelectric receiver 11. The photoelectric receiver // converts the information sequence contained in the light beam 8 into a sequence of electrical signals whose modulation frequency is equal to that iodane in the modulus p 5. The sequence of electrical signals from the photoelectric receiver 11 enters the mixing stage 12, in which the modulation frequency for measurement is subjected to downward transformation due to the frequency generated by the oscillator 13. From the mixing stage 12, an electrical signal lower than the frequency of the signals sent to the mixing stage. Since in the mixing cascade 12 the modulation frequency and frequency of the oscillator can be combined into various transformed frequencies, an electrical filter 15 is provided in the feedback circuit 14 directly behind the mixing cascade 12, which passes only the desired transformed frequency. Two converters 16 and 17 are placed behind the filter 15, between which an internal measuring section 18 is located. The path length of the signal can be changed by moving the converters 16 and 17 relative to each other, for example, by moving the converter 17 relative to the converter 16 to the position indicated by dotted line. The electrical signal from filter 15 is converted into a traveling wave with a transformed frequency, passing through the measurement section 18 at a precisely known speed that is small compared to the speed of light. Wave motion can occur, for example, in the acoustic range. Converter / 7 again transforms the wave motion at the other end of the inner measuring section 18 into an electrical signal with a transformed frequency, after which it enters the mixing cascade 19 controlled by an oscillator 13, which again transforms its frequency into a modulation frequency. The filter 20, which acts like a filter 15, allows through the amplifier 21 to enter the modulator 5 only the initial modulation frequency. The oscillator 13 is connected to the mixing stages 12 and 19 through wires 22. At the section between the converter 17 and the mixing stage 19, an indicator 23, for example, a frequency counter, is connected to the feedback circuit 14. While the oscillator 13, depending on the speed of propagation along the measured section 18, determines the scale ratio between the external measured distance (from the transmitter lens 6 via the reflector 9 to the receiver lens 10) and the internal measured section 18, the indicator 23 indicates The moment when the transducer 17 will be shifted in such a way as to obtain a modulation frequency related to the external measured region, i.e., to produce self-excitation. When the distance is measured by the range finder, the transducer 17 moves along the measured section 18 until the indicator 23 shows the set value. The magnitude of the displacement can then be counted on a calibrated scale in linear units of measure, as the magnitude of the external measured distance. It is advisable to make the measured area in the form of a closed case 24. The transducer 16 is fixedly located on the end wall 25 of the closed case 24 filled with liquid or gas, and the converter 17 is movably mounted on a part 26 that can move parallel to axis X-X. Item 26 on one of its end surfaces is provided with a connecting rod passing through the housing 24 27. The connecting rod passage through the housing 24 is sealed. In addition, the part 26 is provided with channels a connecting the space b of the housing 24 with the space c and allowing the passage of the means filling the measurable area 18, and thus the same pressure in both spaces biv. The housing 24 is provided along its entire length with a window 28 with a digitalized scale 29, in the non-space proximity to which the vernier scale 30 is on the part 26. The subject of the invention The distance meter, for example, is electro-optical, containing a source of electromagnetic radiation directed after modulation and a measured distance, and a receiver that perceives reflected radiation and produces an electrical signal transmitted through a feedback circuit for modulating radiation, the frequency of which is measured, characterized in that, in order to simplify direct display The measurement results in digital form, in the feedback circuit behind the radiation receiver and in front of the amplifier at the modulator input, include mixers connected to a common sinusoidal oscillation generator for lowering and a corresponding reverse increase in the frequency of pulses removed from the receiver, and between the mixers on the adjustable , the measured distance from one another is placed a converter of electrical pulses into a traveling wave with a length corresponding to a lower frequency of the pulses, and the inverse analyzer is converted .

1 and

/ V / - /

2 5

FIG.

2S3G29

2

f -gj% j.