An underwater three-dimensional imaging and communication integrated system

Abstract

The application relates to an underwater three-dimensional imaging and communication integrated system, relates to the field of optical communication technology, and solves the problem of single function of an existing underwater laser three-dimensional imaging system or communication system. The application comprises a computer, a signal generator, a fiber laser, a transmitting fiber, a transmitting fiber collimator, a duplex mirror, a dichroic mirror, a MEMS mirror, a MEMS mirror controller, a beam-reducing mirror, a probe fiber coupler, a probe receiving fiber, a ranging probe, a probe processing circuit, a communication fiber coupler, a communication receiving fiber, a communication probe and a communication demodulator. Through the shared signal generator, the laser, the MEMS mirror, the MEMS mirror controller, the beam-reducing mirror and the communication locator, the system of the application enables the underwater communication system to have the three-dimensional imaging and communication capability while slightly increasing the volume and weight.

Description

Technical Field

[0001] This invention relates to the field of underwater laser three-dimensional imaging and communication technology, specifically to an integrated underwater three-dimensional imaging and communication system. Background Technology

[0002] Three-dimensional imaging can be achieved by combining MEMS resonant scanning with laser ranging technology. Due to the concentrated laser energy in the scanning imaging method, it has the advantage of long detection distance under strong scattering conditions, making it suitable for underwater target detection and underwater topographic mapping, with broad application prospects. The underwater communication system has the advantages of being non-contact and having a high communication rate, enabling the transmission of detected information and greatly improving the efficiency of the detection system.

[0003] Currently, existing laser underwater 3D imaging and communication systems are all single-function systems and cannot achieve two functions in a single system.

[0004] A current Chinese patent publication number, CN 115118345 A, discloses a full-duplex underwater self-aligning wireless laser communication system based on underwater acoustic positioning. This system includes a central control system, an underwater acoustic positioning system, a transmitting system, a receiving system, and a mechanical system. The underwater acoustic positioning system locates two communicating systems, and the mechanical system performs self-alignment based on the positioning information, enabling underwater optical communication. However, it only has communication functionality and cannot achieve three-dimensional imaging of underwater targets. Summary of the Invention

[0005] To address the issue of limited functionality in existing underwater laser 3D imaging or communication systems, this invention provides an integrated underwater laser 3D imaging and communication system, enabling underwater optical communication systems to simultaneously possess 3D imaging capabilities.

[0006] An integrated underwater three-dimensional imaging and communication system, comprising an imaging unit and a communication unit;

[0007] The imaging unit includes a computer, a signal generator, a fiber laser, a transmitting fiber, a transmitting fiber collimator, a duplex mirror, a dichroic beam splitter, a MEMS mirror, a MEMS mirror controller, a beam reducer, a detection fiber coupler, a detection receiving fiber, a ranging detector, and a detection processing circuit.

[0008] The communication unit includes a communication fiber optic coupler, a communication receiving fiber, a communication detector, a communication demodulator, and a communication locator.

[0009] The signal generator generates modulation signals of different frequencies according to different working modes of the computer. The modulation signals are output as pulsed lasers of different modulation frequencies through the fiber laser. The pulsed lasers are output as spatial light through the transmitting fiber collimator.

[0010] The spatial light is reflected by a MEMS mirror after passing through a duplex mirror and a dichroic beam splitter.

[0011] In imaging mode: The reflected beam is directed toward the target by the beam shrinking mirror. After being reflected back by the target's ranging reflection, it is reflected sequentially by the beam shrinking mirror, MEMS mirror, dichroic beam splitter, and duplex mirror. After being coupled into the detection receiving fiber by the detection fiber coupler, it is transmitted to the ranging detector and converted into a received electrical signal. The received electrical signal, together with the signal generator signal and the MEMS mirror controller signal, is integrated in the detection processing circuit to form a three-dimensional image signal that is returned to the computer.

[0012] In communication mode: the reflected light is irradiated onto the communication object by the beam shrinking mirror, and the communication light emitted by the communication object passes through the beam shrinking mirror, MEMS mirror, and dichroic beam splitter in sequence, and is coupled into the communication receiving fiber by the communication fiber coupler. It is transmitted to the communication detector through the communication receiving fiber and converted into an electrical signal. The electrical signal enters the communication demodulator and is converted into a communication digital signal. The communication digital signal is returned to the computer.

[0013] The beneficial effects of this invention are:

[0014] The integrated system described in this invention generates electrical signals at different frequencies in ranging and communication modes through a signal generator; it utilizes two modes of MEMS reflectors: a resonant mode in three-dimensional imaging mode and a point-to-point mode in communication mode; and a duplex reflector and a dichroic beam splitter enable the merging and separation of different types of beams.

[0015] The integrated system described in this invention, by sharing a signal generator, laser, MEMS mirror, MEMS mirror controller, and beam shrinker, enables the underwater communication system to simultaneously achieve three-dimensional imaging and communication capabilities while slightly increasing its size and weight. Attached Figure Description

[0016] Figure 1 This is a block diagram of an integrated underwater three-dimensional imaging and communication system according to the present invention.

[0017] In the diagram: 1. Computer, 2. Signal generator, 3. Fiber laser, 4. Transmitting fiber, 5. Transmitting fiber collimator, 6. Duplex mirror, 7. Dichroic beam splitter, 8. MEMS mirror, 9. MEMS mirror controller, 10. Beam shrinker, 11. Detector fiber coupler, 12. Detector receiving fiber, 13. Ranging detector, 14. Detection processing circuit, 15. Communication fiber coupler, 16. Communication receiving fiber, 17. Communication detector, 18. Communication demodulator, 19. Communication locator. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings.

[0019] like Figure 1 As shown, an integrated underwater 3D imaging and communication system has two working modes: 3D imaging and communication. The system includes an imaging unit and a communication unit. The imaging unit includes a computer 1, a signal generator 2, a fiber laser 3, a transmitting fiber 4, a transmitting fiber collimator 5, a duplex mirror 6, a dichroic beam splitter 7, a MEMS mirror 8, a MEMS mirror controller 9, a beam shrinker 10, a detection fiber coupler 11, a detection receiving fiber 12, a ranging detector 13, and a detection processing circuit 14.

[0020] The communication unit includes a communication fiber optic coupler 15, a communication receiving fiber optic cable 16, a communication detector 17, a communication demodulator 18, and a communication locator 19.

[0021] In 3D imaging mode, the operation process is as follows: Computer 1 sends control commands to signal generator 2. Signal generator 2 sends modulated pulse signals to MEMS mirror controller 9, detection and processing circuit 14, and fiber laser 3. MEMS mirror controller 9 generates a resonant control signal based on the signal from signal generator 2. MEMS mirror 8 resonates according to the control signal. Simultaneously, fiber laser 3 receives the pulse signal and generates modulated pulsed laser light. This light is transmitted through transmitting fiber 4 and transmitting fiber collimator 5 to form spatial light. The spatial light then passes sequentially through duplex mirror 6 and dichroic reflector. The beam 7 is reflected by the MEMS mirror 8 and then illuminated by the beam reducer 10. After the ranging reflection echo returns, it passes through the beam reducer 10, MEMS mirror 8, dichroic beam splitter 7, and duplex mirror 6 in sequence. After being reflected by the reflective surface of the duplex mirror 6, it is coupled into the detection receiving fiber optic cable 12 through the detection receiving fiber optic cable 11. It is transmitted to the ranging detector 13 through the detection receiving fiber optic cable 12 and converted into a received electrical signal. The received electrical signal, the signal of the signal generator 2, and the signal of the MEMS mirror controller 9 are integrated in the detection processing circuit 14 to form a three-dimensional image signal and return it to the computer 1.

[0022] In communication mode, the computer 1 sends a control command to the signal generator 2, which in turn sends a modulated pulse signal to the fiber laser 3. The MEMS mirror controller 9 controls the MEMS mirror 8 to point in the direction of the communication object according to the signal from the locator 19. At the same time, the fiber laser 3 receives the pulse signal and generates a modulated pulse laser. This pulse laser is transmitted through the transmitting fiber 4 and the transmitting fiber collimator 5 to form spatial light. The spatial light passes through the duplex mirror 6 and the dichroic mirror 7 in sequence, is reflected by the MEMS mirror 8, and then passes through the beam reducer 10 to illuminate the communication object. The communication light emitted by the communication object passes through the beam reducer 10, the MEMS mirror 8, and the dichroic beam splitter 7 in sequence, and is then coupled into the communication receiving fiber 16 through the communication fiber coupler 15. The light is then transmitted through the communication receiving fiber 16 to the communication detector 17 and converted into a received electrical signal. The received electrical signal enters the communication demodulator 18 and is converted into a communication digital signal. The communication digital signal is then returned to the computer 1.

[0023] In this embodiment, the signal generator 2 generates modulation signals of different frequencies under different working modes according to the computer program. The modulation signals enter the fiber laser 3, and the fiber laser 3 emits laser pulses of different modulation frequencies according to the modulation signals. The pulsed laser enters the transmitting fiber collimator 5 through the transmitting fiber 4 and is output as spatial light. The dichroic beam splitter 6 realizes the separation of the detection laser and the communication laser. The duplex mirror 7 realizes the merging and separation of the detection transmitted light and the detection received light. The MEMS mirror 8 realizes the scanning and pointing of the transmitted beam and the received beam. The MEMS mirror controller 9 is used to realize the control of the angle of the MEMS mirror. The beam shrinking mirror 10 realizes the magnification or reduction of the pointing angle. The communication locator provides the pointing angle information to the MEMS mirror 8. The detection fiber coupler 11 is used to couple the detection laser echo into the detection receiving fiber 12. The detection receiving fiber 12 realizes optical transmission. The detection laser finally enters the ranging detector 13 and is converted into an electrical signal. The detection processing circuit 14 integrates the electrical signals of the signal generator 2, the MEMS mirror controller 9, and the ranging detector 13 to form a three-dimensional image and send it to the computer.

[0024] The communication fiber optic coupler 15 is used to couple the communication light into the detection and receiving fiber optic 16. The communication receiving fiber optic 16 realizes optical transmission. The communication laser finally enters the communication detector 17 and is converted into an electrical signal. The communication demodulator 18 converts the communication electrical signal into a digital communication signal and sends it to the computer 1. The communication locator 19 provides information to the MEMS mirror controller 9.

[0025] In this embodiment, the signal generator 2 can emit electrical signals at different frequencies in ranging and communication modes; the fiber laser 3 can generate pulsed lasers according to the signals from the signal generator, with laser wavelengths of 532nm or 480nm; the transmitting fiber 4 is a single-mode fiber with a working wavelength of visible light; the transmitting fiber collimator 5 can collimate the pulsed laser in the single-mode fiber into space; the duplex mirror 6 has a small hole in the middle through which the emitted laser passes, and the reflecting surface has high reflectivity in the 532nm or 480nm band; the dichroic beam splitter 7 can reflect 532nm lasers and transmit 480nm lasers, or transmit 532nm lasers and reflect 480nm lasers.

[0026] In this embodiment, the MEMS reflector 8 has two working modes: resonance and point-to-point. It can feed back the actual deflection angle of the mirror to achieve closed-loop control, and has a mirror size of more than 10mm and a deflection range of more than 10°. The MEMS reflector controller 9 can control the MEMS reflector 8 to resonate or fix its pointing to a certain angle. The beam shrinking mirror 10 can amplify the deflection angle or the receiving aperture.

[0027] In this embodiment, the detection fiber coupler 11 has a narrowband filter, which, by having a wavelength the same as the laser wavelength, can couple the emitted laser echo into the detection receiving fiber; the detection receiving fiber 12 is a few-mode or multi-mode fiber; the ranging detector 13 is a visible light APD detector with gating function; the detection processing circuit 18 can integrate the signals from the signal generator 2, the ranging detector 13, and the MEMS reflector controller 9 to generate a three-dimensional image.

[0028] In this embodiment, the communication fiber coupler 15 has a narrowband filter, which couples the emitted laser echo into the detection and receiving fiber 16 by means of a wavelength different from that of the laser. The communication receiving fiber 16 is a few-mode or multi-mode fiber. The communication detector 17 is a high-speed visible light APD detector. The communication demodulator 18 can convert electrical communication signals into digital communication signals and send them to the computer 1. The communication locator 19 is a tracking camera or a short-baseline acoustic locator, which can detect the location of the communication object and provide information to the MEMS mirror controller 9.

[0029] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0030] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. An integrated underwater three-dimensional imaging and communication system, characterized in that: The system includes an imaging unit and a communication unit; The imaging unit includes a computer (1), a signal generator (2), a fiber laser (3), a transmitting fiber (4), a transmitting fiber collimator (5), a duplex mirror (6), a dichroic beam splitter (7), a MEMS mirror (8), a MEMS mirror controller (9), a beam shrinker (10), a detection fiber coupler (11), a detection receiving fiber (12), a ranging detector (13), and a detection processing circuit (14). The communication unit includes a communication fiber optic coupler (15), a communication receiving fiber optic cable (16), a communication detector (17), a communication demodulator (18), and a communication locator (19). The signal generator (2) generates different frequency modulation signals according to different working modes of the computer (1). The modulation signals output pulsed lasers with different modulation frequencies through the fiber laser (3). The pulsed lasers enter the transmitting fiber collimator (5) through the transmitting fiber (4) and are output as spatial light. The spatial light is reflected by the MEMS mirror (8) after passing through the duplex mirror (6) and the dichroic beam splitter (7); In imaging mode: the reflected beam is irradiated towards the target by the beam shrinking mirror (10), and after being reflected back by the target's ranging reflection echo, it is reflected sequentially by the beam shrinking mirror (10), MEMS mirror (8), dichroic beam splitter (7), duplex mirror (6) and then coupled into the detection receiving fiber (12) through the detection fiber coupler (11). It is transmitted to the ranging detector (13) through the detection receiving fiber (12) and converted into an electrical signal. The electrical signal, together with the signal of the signal generator (2) and the signal of the MEMS mirror controller (9), is integrated in the detection processing circuit (14) to form a three-dimensional image signal that is returned to the computer (1). In communication mode: the reflected light is irradiated onto the communication object by the beam shrinking mirror (10), and the communication light emitted by the communication object passes through the beam shrinking mirror (10), MEMS mirror (8), and dichroic beam splitter (7) in sequence, and is coupled into the communication receiving fiber (16) through the communication fiber coupler (15). It is transmitted to the communication detector (17) through the communication receiving fiber (16) and converted into an electrical signal. The electrical signal enters the communication demodulator (18) and is converted into a communication digital signal. The communication digital signal is returned to the computer (1).

2. The underwater three-dimensional imaging and communication integrated system according to claim 1, characterized in that: The duplex mirror (6) separates the detection laser from the communication laser, the dichroic beam splitter (7) merges and separates the detection emitted light and the detection received light, the MEMS mirror (8) scans and points the emitted beam and the received beam, the MEMS mirror controller (9) controls the angle of the MEMS mirror, the beam shrinker (10) amplifies or reduces the pointing angle, and the communication locator (19) provides pointing angle information to the MEMS mirror (8).

3. The underwater three-dimensional imaging and communication integrated system according to claim 1, characterized in that: The MEMS mirror (8) has two working modes: resonance and point-to-point. The resonance mode is used in the imaging mode, and the point-to-point mode is used in the communication mode.

4. The underwater three-dimensional imaging and communication integrated system according to claim 1, characterized in that: The communication locator (19) is a tracking camera or a short baseline acoustic locator used to detect the location of the communication object and provide information to the MEMS mirror controller (9).

5. The underwater three-dimensional imaging and communication integrated system according to claim 1, characterized in that: The fiber laser (3) generates pulsed laser according to the signal from the signal generator, and the pulsed laser wavelength is 532nm or 480nm.

6. The underwater three-dimensional imaging and communication integrated system according to claim 1, characterized in that: The duplex mirror (6) has a small hole in the middle through which the emitted laser passes, and the reflecting surface has high reflectivity in the 532nm or 480nm band.

7. The underwater three-dimensional imaging and communication integrated system according to claim 1, characterized in that: The dual-color beam splitter (7) reflects 532nm laser and transmits 480nm laser, or transmits 532nm laser and reflects 480nm laser.

8. The underwater three-dimensional imaging and communication integrated system according to claim 1, characterized in that: Both the detection receiving fiber (12) and the communication receiving fiber (16) are few-mode or multi-mode fibers.

9. The underwater three-dimensional imaging and communication integrated system according to claim 1, characterized in that: Both the ranging detector (13) and the communication detector (17) are visible light APD detectors.

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