RU2453866C2 - Optical locator of circular scan - Google Patents

Abstract

FIELD: radio engineering.

SUBSTANCE: optical locator with a scanning device in the form of a hollow cylinder being a rotor of an electric motor, with holes at both ends and two optical hatches. A channel to receive optical radiation from an object having a temperature contrast uses one hatch. A transceiving channel with an inbuilt television sensor and sensors to receive laser's radiation reflected from an object uses a different hatch. The scanning device, on a generatrix of a cylinder of which there are two hatches fixed with transparency to different ranges of optical wavelengths. Inside the cylinder oppositely to each hatch there is a scanning dead mirror. The scanning dead mirror of the transceiving channel in the mode of inbuilt monitoring of the optical locator in dynamics reflects laser radiation. Laser radiation starts at the moment a sighting axis of the scanning device matches coordinates set by a processor, and when hitting a mirror lens of an inbuilt control unit (ICU), divides into two parts. One part of the radiation focuses on a target of the inbuilt control unit. The other part of the laser's radiation via a hole in the mirror lens gets into the optical delay line, where it is retained in time and returns back strictly in the same direction.

EFFECT: implementation of dynamic control of optical locators with a universal device of optical radiation delay, expansion of optical range.

3 cl, 6 dwg

Description

The invention relates to the field of optical location and is intended for search, detection and automatic tracking of air objects having optical contrast, with the determination of their spatial coordinates.

The following optical location systems are known, for example: B.F. Fedorov “Lasers. Fundamentals of device and application ", Moscow, 1988, pp. 141-146, G. P. Katys" Automatic scanning ", Moscow, 1967, ed. "Engineering", p. 326, G.P. Katys "Optoelectronic processing of information", Moscow, 1973, ed. "Mechanical Engineering", p. 416, RU No. 2071101, G02B 26/10, RU No. 2084925, G01S 17/06, RU No. 2352957, RU No. 229231, SU No. 1378604, G01S 17/06, DE No. 3935683, G01S 17 / 00, Special Technology Magazine No. 6, 2005, “Lifting Mobile Night Vision Devices” (TADS System).

Optical location systems, as a rule, contain passive sensors of various optical ranges. Sources of electromagnetic radiation in the optical range for these devices are lasers operating in pulsed or continuous mode. Separate optical devices serve both to transmit laser radiation and to receive radiation reflected from the object of observation. In some optical location systems, individually adapted optical forming devices for passive sensors operating in various optical ranges are used, as well as scanning devices for viewing a given space. The signals from the sensors are processed by a microprocessor, which is also used for integrated control and the issuance of the necessary information to an external device.

Among the known locators, the following disadvantages can be noted: it is difficult to manufacture a usable single optical hatch, which works for reception and transmission in a wide optical range; built-in control is carried out only in static mode; limited time review of spatial coordinates scanned by the locator.

In this regard, the most satisfactory technical solution "Optical radar circular viewing" (patent RU No. 2352957, filing date 09.06.2005, publication date 07.27.2008). Its main disadvantage is the difficulty in manufacturing the only operable optical hatch operating in the reception and transmission in a wide optical range (for example, at λ = 0.2–14 μm). In addition, an integrated dynamic control unit, which is necessary in optical locators with a high speed of viewing the space during long and continuous operation, is not disclosed in terms of technical implementation.

The technical result of the claimed invention is the implementation of dynamic control of optical locators with a universal device for delaying optical radiation, as well as expanding the optical range used in these locators.

The invention is a compact optical radar circular view with a scanning device in the form of a hollow cylinder, which is the rotor of the electric motor (Figure 1, pos. 48), with holes at both ends and two optical hatches deployed on the generatrix of this cylinder by 180 ° and serving for the passage of incoming and outgoing optical signals of various wavelengths through optical elements that are built into the cylinder. A channel for receiving optical radiation from an object having a temperature contrast uses one hatch; another hatch is designed for a transceiver channel with an integrated television sensor and sensors for receiving radiation reflected from the object. This hatch is also used for dynamic integrated control of the optical locator.

The invention is illustrated by drawings:

Figure 1 is a front view of the MLC,

Figure 2 is a view of the MLC when operating the built-in control (1st and 3rd time interval),

Figure 3 is a view of the MLC when operating the built-in control (2nd time interval),

Figure 4 - block optical delay (BOS),

Figure 5 - block conversion of wavelength and divergence (BWR),

6 is a functional diagram of the connections of blocks and nodes OLKO.

To solve this problem, the design of a pulsed laser transceiver channel (PPC) in this optical locator is made in accordance with the patent "Optical radar circular viewing" RU No. 2352957, filing date 09.06.2005, publication date 04/20/2009. A PIK operating at three optical wavelengths is combined to transmit and receive optical energy through one controlled telescope (UT) (Figure 1, item 14).

This solution was achieved by using an optical switch (OP) (Figure 5, item 16), which commutates the optical control system in three positions according to the patent "Device for orienting the light beam" RU No. 2029239, application date 08.06.1992, publication date 27.12 .1996.

In position “a” of the double-sided mirror (FIG. 5, pos. 42), the electronic optical converter included in the TV channel (FIG. 5, pos. 49) is used, which receives radiation reflected from the object and transmits it to the TV channel sensor . In two other positions of the double-sided mirror “b” and “c”, the OP provides reception to the sensors from the radiation object at one of two optical wavelengths specified by a command from the processor (PR) (Fig. 6, item 47).

Laser (patent RU No. 2073945, 02.20.1997, application filing date 01/13/1994, publication date 02/20/1997) together with the radiation wavelength conversion unit (Fig. 5, pos. 37), combined with a radiation divergence control device (Fig. 5, pos. 38) in the general BVRV block (Fig. 5, pos. 17) (RU patent No. 2352957, application filing date 09.06.2005, publication date 04/20/2009), upon command from the PR, emits radiation with the given optical wavelength and divergence angle. The infrared channel (PC) (Figure 1, pos. 1-6) detects objects with temperature contrast. The composition of the channel includes sensors in the form of rulers (Fig. 1, pos. 1, pos. 2), sensitive to temperature contrast in the optical range λ = 3.0 ÷ 14.0 μm, mirror prism "Dove" (Fig. 1, pos. 7), a mirror lens with corrective optics (Fig. 1, pos. 10, pos. 3, pos. 4), a spectro-splitting mirror (Fig. 1, pos. 5) and a blind mirror (Fig. 1, pos. 6).

Figure 6 shows a functional diagram of the management of all blocks and nodes of the MLC.

The design of the OLCO in the form of a console allows you to place the built-in control unit (IAC) with an optical delay unit (BOS) (Fig. 1, pos. 27, pos. 22) in an area that overlaps the overview of the investigated space of the control system (Fig. 1, pos. 13) .

The delay of the optical radiation of a pulsed laser in the BOS is carried out using an optical fiber (Figure 4, item 31), one end of which has a mirror coating with predetermined reflection and transmission coefficients (Figure 4, item 30), and at the other end of the optical fiber a lens is mounted (Fig. 4, item 32), in the focal plane of which is the end face of this optical fiber. A mirror is mounted in front of the lens perpendicular to the target axis of the lens with fiber (Fig. 4, pos. 33) with predetermined reflection and transmission coefficients, as well as at an angle to the target axis of the lens with optical fiber, a plane-parallel optical plate (Figure 4, pos. 34) with given reflection and transmission coefficients. The part of the laser radiation that passed through the hole on the mirror lens (Figure 1, item 20) in the radiation zone of the control panel (Figure 2, item falls into the BOS. The radiation transmitted through the hole, reflected from the plane-parallel plate, enters through the lens (Figure 1). 4, pos. 35) to the radiation power measurement unit (BIM) (Fig. 4, pos. 36). The power value obtained in the BIM determines the part of the laser radiation, which, taking into account the transmittance of the inclined plane-parallel plate and mirror (Fig. 4, pos. 33) with a given transmittance gets through about lens (Figure 4, 32) in the optical fiber.

The laser radiation delayed in the BOS is returned strictly parallel to the incoming laser radiation if this radiation occurred in the coordinates specified by the PR. The coordinates for the incoming radiation are structurally determined by the line of sight of the lens, in the focal plane of which is the end face of the optical fiber (Figure 4, 32, 31).

Depending on the requirements of a particular device for the built-in control, the maximum interval for the delay of pulses is determined by the BOS parameters according to the formula

- задержка сигнала при однократном прохождении излучения через оптическое волокно, сек;

- signal delay with a single passage of radiation through an optical fiber, sec;

s is the speed of light (≈300000 km / s);

n is the refractive index of the optical fiber (≈1.5);

2L — fiber length per one cycle of radiation passing through an optical fiber, km;

m-1 - the number of cycles of passage of radiation through an optical fiber;

Ф ₀ - radiation flux arriving at the optical fiber, W;

P _min = µP _then - the minimum value of the radiation flux, which provides a given probability of correct detection, W;

µ is the required signal-to-noise ratio;

P _then - threshold sensitivity of the transceiver channel sensor, W;

η1 is the transmittance of the optical element 36;

1-η ₁ is the reflection coefficient of the optical element 36;

ρ is the reflection coefficient of the optical element 33;

η3 is the transmittance of the inclined plane-parallel plate 37;

γ = 0.1 β 1n 10 - parameter characterizing the attenuation of radiation in the optical fiber 34, km ^-1 ;

β is the attenuation coefficient of the optical fiber at a wavelength of laser radiation, dB / km.

The obtained sequence of pulses delayed in the BOS from the radiation of the PPC laser makes it possible to evaluate the detection ability of the receive path of the PPC channel (minimum signal-to-noise ratio) in the range of given ranges of this channel.

The built-in control is carried out during the operation of the OLCO for three time intervals at which the coordinates of the simulator of the observed object in the BVC in terms of elevation and azimuth remain unchanged.

First time interval

With PR, a command is issued for the emission of the PPC of a given optical wave, as well as a command for receiving reflected and delayed radiation from the BOS by the TV channel (Figure 5, item 49); the position of the two-way mirror (Figure 5, pos. 42) in "a". At the moment of coincidence of the target axis of the SU mirror (FIG. 2, item 12) with the coordinates given from the PR, a command is issued to emit the PPK laser (FIG. 6, item 18). Laser radiation through the optical sunroof SU (Figure 2, pos. 28), the optical sunroof of the BVK (Figure 2, pos. 25), reflected from the mirror lens of the BVK (Figure 2, pos. 20) and the blind mirror (Figure 2 , pos.24), hits the target of the built-in control (Figure 2, pos.23). The target mounted in the focal plane of the mirror lens is made of a material with minimal thermal conductivity and maximum absorption at the laser radiation wavelength (for example, blackened plug). At the point of the laser radiation, the target material is heated. At the same time, part of the radiation through the hole located on the mirror lens in the radiation zone of the PPK laser (Figure 2, item 21) falls into the BOS (Figure 2, item 22), where, passing through an inclined plane-parallel plate (Figure 4 , pos. 34), the mirror (Fig. 4, pos. 33) and the lens (Fig. 4, pos. 32) fall into the optical fiber. The laser radiation delayed in time in the optical fiber is projected back through the BVK hatch (Figure 4, item 25) and the SU hatch (Figure 4, item 28) onto the mirror of the SU (Figure 4, item 12) and UT (Fig. .4, pos. 14), then through the block OP is fixed on the matrix in the TV channel, and the coordinates of this place are stored in the PR.

The second time interval is equal to the turn time of the control system by 180 degrees.

The radiation of the contrast (heated) point on the target (Fig. 3, pos. 3) is transmitted by the BVK mirror lens through the BVK hatch (Fig. 3, pos. 26) and the SU hatch (Fig. 3, pos. 29) is reflected by the SU mirror ( Fig.3, pos.11), a mirror lens (Fig.3, pos.10), a dull mirror (Fig.3, pos.10), passing the Dove prism, a spectro-splitting mirror (Fig.3, pos.5) and corrective optics (Figure 3, 4), falls on the sensor (Figure 3, 2). Another part of the radiation (heated point), reflected from the spectro-dividing mirror (Fig. 3, pos. 5) and from a deaf mirror (Fig. 3, pos. 6), enters the sensor (Fig. 3, pos. 1). The obtained coordinates of both sensors are processed and stored in the PR.

The third interval is equal to the rotation time of the control system by 360 degrees.

After receiving a laser radiation signal delayed in the BHP and fixed by the TV channel in the first time interval, a command is issued from the PD to the BWPK PPK to switch to the reception mode of reflected and delayed laser radiation pulses from the BHP to the sensor, which is adequate to the specified optical wavelength of radiation from the BWR in PPK - the position of the double-sided mirror (Figure 5, pos. 42) “b” or “c”. At the time of the secondary passage of the target axis of the SU mirror (FIG. 2, item 12) of two coordinates specified from the PR, a command is issued from the PR to the laser radiation, which, falling into the BOS (FIG. 22) through the hole in the mirror lens (FIG. 2, pos. 21) in the laser radiation zone, it must return strictly in the same direction back as the radiation incident on the BOS. The delayed radiation from the BOS passes through the hatches (Figure 2, item 25, item 28), is reflected from the mirror (Figure 2, item 12) and, getting into the UT and PPC, is fixed by the sensor in the OP (Figure 5, item .40 or item 41). The signal received from the sensor is processed in the PR, where the parameters of the control panel are determined.

Thus, in a single rotation of the control system by 360 ° in the VLCO, all channels operating from the temperature contrast of the observed object, operating at the natural contrast of the observed object, the active backlight PPC, have strictly parallel optical scanning axes in space corresponding to the fixed coordinates in the PR memory block.

The radiation of the PPC laser passing through the BOS, getting back into the PPC, provides control of the optical locator by the accuracy of the laser radiation hit the point with the given spatial coordinates when scanning the studied space, gives the TV channel axis binding to the PPC laser radiation and determines the specified minimum signal ratio / noise photodetector sensor PPC.

The claimed design solution of the optical radar circular visor meets the criterion of industrial applicability and can be manufactured at the enterprises of the optical-mechanical industry.

Legend

1. The sensor at λ = 8 ÷ 14 microns

2. The sensor at λ = 3 ÷ 5 microns

3. Corrective optics at λ = 8 ÷ 14 microns

4. Corrective optics at λ = 3 ÷ 5 microns

5. Spectro-splitting mirror (λ = 3 ÷ 5 μm / λ = 8 ÷ 14 μm)

6. Deaf mirror at λ = 8 ÷ 14 microns

7. Prism Dove

8. Gear connection of the cage with the Dove prism with a rotating housing with optics

9. Deaf mirror at λ = 3 ÷ 14 microns

10. Mirror lens at λ = 3 ÷ 14 μm

11. Scanning blind mirror of the channel λ = 3 ÷ 14 μm

12. Scanning blind mirror of the channel λ = 0.2 ÷ 5.0 μm

13. A rotating cylinder with optics of a scanning device (SU)

14. Guided telescope

15. Deaf mirror at λ = 0.2 ÷ 2.0 μm

16. Optical switch

17. The converter of the wavelength and the divergence of the laser radiation (BWR)

18. Pulsed laser

19. Torsion connection of scanning mirrors

20. Mirror lens BVK

21. The hole in the mirror lens BVK

22. Block optical delay (BOS)

23. Target built-in control

24. Deaf mirror BVK

25. Optical sunroof BVK for a laser transceiver channel and a TV channel

26. Optical sunroof BVK for IR channels

27. Block of built-in control (BVK)

28. Optical sunroof for laser transceiver channel and TV channel

29. Optical sunroof for IR channels

30. Mirror coating with a given reflectance and transmittance

31. Optical cable

32. The lens to the optical cable

33. Mirror with a given reflection and transmittance

34. Plane-parallel plate with a given reflection and transmission coefficient

35. The lens for the unit for measuring radiation power

36. Block measurement of radiation power (BIM)

37. Device for converting a wavelength of radiation

38. Device for converting the divergence of radiation

39. Unit with TV sensor

40. Sensor for receiving radiation at a wavelength of λ1

41. Sensor for receiving radiation at a wavelength of λ2

42. Double-sided blind mirror

43. 44, 45, 46. Deaf mirrors

47. The processor

48. Motor rotor and rotor position code disk

Claims (3)

1. The optical radar circular view with a scanning device in the form of a hollow cylinder, which is the rotor of the electric motor, with holes at both ends and two optical hatches, which serve for the passage of incoming and outgoing optical signals of different wavelengths through optical elements that are built into the cylinder: channel for receiving optical radiation from an object having a temperature contrast uses one hatch; the transceiver channel with a built-in television sensor and sensors for receiving laser radiation reflected from the object uses another hatch, through which dynamic built-in control of the optical locator is also implemented, characterized in that the scanning device with holes at both ends, on the cylinder generatrix of which two hatches with transparency are fixed on different ranges of optical wavelengths, as well as inside the cylinder against each hatch, a perp fixed to the axle is deflected, deflecting on the axes which are opposite to the axis of rotation of the cylinder oppositely relative to each other at equal angles by means of rollers of the same diameter, rigidly fixed on these axes and connected by a torsion bar mounted on these rollers, the scanning blind mirror of the transceiver channel in the built-in control of the optical locator in the dynamics reflects laser radiation , which is turned on at the moment of coincidence of the sighting axis of the scanning device with the coordinates specified by a command from the processor, and, getting on the mirror lens unit built-in control (BVK), is divided into two parts, where one part of the radiation is focused on the target of the built-in control unit, and the other part of the laser radiation through the hole in the BVK mirror lens, located at the spot of the laser radiation on the BVK mirror lens, falls into the optical delay line integrated control unit, including optical fiber, where it is delayed in time and returns back exactly in the same direction as the radiation incident on the optical delay line. 2. The optical circular viewing locator according to claim 1, characterized in that the built-in control unit includes a device that allows using laser mirror of the built-in control unit with an additional hole to divide the laser radiation incident on the mirror lens into two components: one component, reflected from the mirror lens hits a target with maximum absorption and minimum thermal conductivity at the optical wavelength of the laser radiation, located in the focal plane of this lens and transforming conductive laser energy to heat the target point; the other part of the laser radiation, passing through the hole in the mirror lens in the laser radiation zone, enters the block of the optical delay line, where it is delayed in time and leaves the hole in exactly the same direction as the laser radiation entering the delay line, if the laser radiation has occurred exactly along the line of sight of the given coordinates of the optical delay unit. 3. The optical locator according to claim 1, characterized in that the time delay of the radiation of a pulsed laser in the optical delay unit is carried out using an optical fiber installed in it, in which one end has a mirror coating with predetermined reflection and transmittance, and at the other end of the optical fiber, a lens is installed, in the focal plane of which is placed the other end of this optical fiber, as well as a mirror mounted perpendicular to the sight axis of the lens, with given coefficients reflected I and transmission, which are selected from the formula with specified parameters for a particular device

Where

- signal delay with a single passage of radiation through an optical fiber, s;
s is the speed of light (≈300000 km / s);
n is the refractive index of the optical fiber (≈1.5);
2L — fiber length per one cycle of radiation passing through an optical fiber, km;
m - 1 - the number of cycles of transmission of radiation through an optical fiber;
Ф ₀ - radiation flux arriving at the optical fiber, W;
P _min = µP _then - the minimum value of the radiation flux, which provides a given probability of correct detection, W;
µ is the required signal-to-noise ratio;
P _then - threshold sensitivity of the transceiver channel sensor, W;
η ₁ - transmittance of the mirror mounted in front of the lens;
1 - η ₁ - reflection coefficient of the mirror mounted in front of the lens;
ρ is the reflection coefficient of the mirror coating of the end of the optical fiber;
η ₃ - transmittance of an inclined plane-parallel plate;
γ = 0.1 β 1n 10 - parameter characterizing the attenuation of radiation in the optical fiber, km ^-1 ;
β is the attenuation coefficient of the optical fiber at a wavelength of laser radiation, dB / km,
as well as a plane-parallel plate with predetermined reflection and transmission coefficients, mounted at an angle to the line of sight of the lens, which reflects part of the radiation in the unit for measuring the power of this radiation, and the part of the radiation passing through the plate determines the amount of laser radiation entering the optical fiber.

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