A non-contact coaxial long-distance water surface oil spill monitoring method

Abstract

The present invention discloses a non-contact coaxial long-distance water surface oil spill monitoring method, comprising the following steps: 1) coaxial optical system calibration; 2) obtaining image information of the target to be measured, adjusting the position of the secondary mirror, so that the focus of the telescope mechanism is positioned on the surface of the target to be measured; 3) the pulse laser passes through the semi-transparent and semi-reflective prism after the beam expander to enter the telescope mechanism, and is focused on the surface of the target to be measured; 4) the pulse laser excites the target to be measured to emit a fluorescent signal; 5) the image data of the camera and the spectral data of the spectrometer are analyzed and processed to obtain oil spill monitoring information. The present invention optimizes the optical system of oil spill monitoring, reduces its weight, facilitates long-distance monitoring by aircraft, improves monitoring performance through automatic focusing, and ensures signal strength.

Description

Technical Field

[0001] The invention relates to the technical field of water surface oil spill monitoring, and in particular to a non-contact coaxial long-distance water surface oil spill monitoring method. Background Art

[0002] With the rapid development of the aquatic industry, oil spills are becoming more frequent, posing a serious threat to the natural environment and human health. Therefore, real-time monitoring of oil spills, rapid detection and alarm measures are extremely important for rapid response to accidents and mitigation of the harm caused by leaks. At present, oil spill monitoring methods mainly include optical detection and electromagnetic wave detection. Among them, the ultraviolet fluorescence induction method in optical detection is the most common. Its working principle is that the conjugated structure in oil substances absorbs specific ultraviolet light energy, thereby stimulating fluorescence in a specific band. By observing the presence or absence of fluorescence signals, it is possible to determine whether an oil spill has occurred.

[0003] Oil spill monitoring equipment is usually used in fixed areas such as docks and coasts. This installation method greatly limits its scope of use. Therefore, in order to improve the monitoring range and flexibility of oil spill monitoring equipment, the use of drones to carry oil spill monitoring equipment is a future trend. However, the current oil spill monitoring equipment still has some problems: large size, short monitoring distance, and poor signal. Summary of the invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, it is desired to provide a non-contact coaxial long-distance surface oil spill monitoring method, which optimizes the optical system to reduce its weight, facilitates long-distance monitoring on an aircraft, improves monitoring performance through automatic focusing, and ensures signal strength.

[0005] The present invention provides a non-contact coaxial long-distance water surface oil spill monitoring method, comprising the following steps:

[0006] 1) Coaxial optical system correction;

[0007] 11) Place the CCD camera or CMOS camera in front of the telescope mechanism. The pulsed laser emitted by the laser enters the telescope mechanism through the beam expander and the semi-transparent and semi-reflective prism, and is focused on the detection surface of the CCD camera or CMOS camera by the telescope mechanism to form image A.

[0008] 12) Replace the green auxiliary light source and install it in the position of the light receiving device. Turn on the green auxiliary light source. The light with a wavelength of 532-562nm emitted by it enters the telescope mechanism through the reflector and the semi-transparent and semi-reflective prism, and is focused on the detection surface of the CCD camera or CMOS camera through the telescope mechanism to form image B.

[0009] 13) Adjust the angle of the reflector so that the image A detected by the CCD camera or CMOS camera overlaps with the image B;

[0010] 2) Obtain image information of the target to be measured through the camera, and control the stepper motor to drive the secondary mirror to move according to the clarity of the image information to adjust the position of the secondary mirror so that the focus of the telescope mechanism is located on the surface of the target to be measured;

[0011] 3) The trigger laser emits a pulsed laser, which passes through the beam expander, through the semi-transparent and semi-reflective prism, and enters the telescope mechanism to be focused on the surface of the target to be measured;

[0012] 4) The pulsed laser excites the target to be measured to emit a fluorescent signal. The radiated fluorescent signal passes through the telescope mechanism, and then enters the beam splitter after being reflected by the semi-transparent and semi-reflective prism and the reflector. The fluorescent signal is split into two beam splitting paths by the beam splitter. One beam splitting path enters the camera, and the other beam splitting path is collected by the light receiving device and transmitted to the spectrometer via optical fiber.

[0013] 5) Analyze and process the camera’s image data and the spectrometer’s spectral data to obtain oil spill monitoring information.

[0014] Furthermore, the coaxial optical system comprises:

[0015] The laser emitting mechanism comprises a laser, wherein a beam expander is arranged at the output end of the laser, and a semi-transparent and semi-reflective prism is arranged at a side of the beam expander away from the laser;

[0016] A telescope mechanism is arranged at the output end of the laser emitting mechanism, comprising a lens barrel, a primary mirror is arranged at the rear end of the lens barrel, a light shielding tube is arranged at the front end of the lens barrel, a secondary mirror is arranged between the primary mirror and the light shielding tube in the lens barrel, and a stepping motor driving the secondary mirror to move forward and backward along the axial direction of the lens barrel;

[0017] The reflected signal receiving mechanism comprises a reflector, which is arranged on the reflected light path of the semi-transparent and semi-reflective prism. A spectroscope is arranged on the reflected light path of the reflector. A camera is arranged on one of the spectroscope paths, and a light receiving device is arranged on the other spectroscope path. The light receiving device is connected to a spectrometer via an optical fiber.

[0018] Furthermore, the coaxial optical system is arranged on an aircraft; the aircraft is a drone.

[0019] Furthermore, the wavelength of the pulse laser emitted by the laser is 325-365nm.

[0020] Furthermore, the camera and the spectrometer are connected to the data processing module via a wireless communication module.

[0021] Furthermore, a power supply module is provided on the aircraft, and the laser emitting mechanism, the telescope mechanism and the reflected signal receiving mechanism are all electrically connected to the power supply module.

[0022] Furthermore, a data storage module is provided on the aircraft, and the camera and the spectrometer are both electrically connected to the data storage module.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] 1) The present invention improves the optical system of existing oil spill monitoring equipment and specifically designs a coaxial optical path system configured on an aircraft, which greatly reduces its lateral volume and weight, making it easier to carry it on a drone for long-distance monitoring. The telescope mechanism also realizes automatic focus search, greatly improving the signal reception intensity and meeting the needs of long-distance transmission. It does not need to install a traditional laser ranging system to assist in ranging, further reducing the weight of the equipment.

[0025] 2) The coaxial optical system is adopted. At different monitoring distances, there is no need to change the angle between the laser emitting mechanism and the reflected signal receiving mechanism, which is more convenient to use. As the monitoring distance changes, the laser excitation area of ​​the coaxial optical system and the reflected signal receiving field of view always have a large overlap rate, and the light source utilization rate is high.

[0026] 3) The telescope mechanism is used to achieve higher altitude oil spill monitoring, which not only ensures accurate monitoring but also avoids the risk of collision with other ships, thus providing high safety.

[0027] It should be understood that the contents described in the summary of the invention are not intended to limit the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0029] Figure 1 It is the structural block diagram of the oil spill monitoring device;

[0030] Figure 2 It is a schematic diagram of the optical path of the coaxial optical system;

[0031] Figure 3 Schematic diagram of the optical path for coaxial optical system correction.

[0032] Numbers in the figure: 1. Laser emitting mechanism; 2. Telescope mechanism; 3. Reflection signal receiving mechanism; 4. Target to be measured; 5. CCD camera or CMOS camera; 6. Green auxiliary light source;

[0033] 11. Laser; 12. Beam expander; 13. Semi-transparent and semi-reflective prism;

[0034] 21. Lens barrel; 22. Primary mirror; 23. Light shielding barrel; 24. Secondary mirror; 25. Stepping motor;

[0035] 31. Reflector; 32. Spectroscope; 33. Camera; 34. Light collecting device; 35. Optical fiber; 36. Spectrometer. DETAILED DESCRIPTION

[0036] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It should also be noted that, for ease of description, only the parts related to the invention are shown in the accompanying drawings.

[0037] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0038] Please refer to Figure 1~Figure 3 The embodiment of the present invention provides a non-contact coaxial long-distance water surface oil spill monitoring method, comprising the following steps:

[0039] 1) Coaxial optical system correction;

[0040] 11) The CCD camera or CMOS camera 5 is placed in front of the telescope mechanism 2. The pulse laser emitted by the laser 11 enters the telescope mechanism 2 through the beam expander 12 and the semi-transparent and semi-reflective prism 13, and is focused on the detection surface of the CCD camera or CMOS camera 5 by the telescope mechanism 2 to form an image A.

[0041] 12) Replace the green auxiliary light source 6 and install it at the position of the light receiving device 34, turn on the green auxiliary light source 6, and the light with a wavelength of 532-562nm emitted by it enters the telescope mechanism 2 through the reflector 31 and the semi-transparent and semi-reflective prism 13, and is focused on the detection surface of the CCD camera or CMOS camera 5 through the telescope mechanism 2 to form an image B;

[0042] 13) Adjust the angle of the reflector 31 so that the image A detected by the CCD camera or the CMOS camera 5 overlaps with the image B, so that the laser emitting mechanism 1 and the reflected signal receiving mechanism 3 are coaxial, thereby improving the performance of the oil spill monitoring device;

[0043] 2) acquiring image information of the target 4 to be measured through the camera 33, and controlling the stepping motor 25 to drive the secondary mirror 24 to move according to the clarity of the image information, so as to adjust the position of the secondary mirror 24 so that the focus of the telescope mechanism 2 is positioned on the surface of the target 4 to be measured;

[0044] 3) The trigger laser 11 emits a pulse laser, which passes through the beam expander 12, the semi-transparent and semi-reflective prism 13, and enters the telescope mechanism 2, and is focused on the surface of the target 4 to be measured;

[0045] 4) The pulsed laser excites the target 4 to emit a fluorescence signal. The radiated fluorescence signal passes through the telescope mechanism 2, and then enters the beam splitter 32 after being reflected by the semi-transparent and semi-reflective prism 13 and the reflector 31. The fluorescence signal is split into two light paths by the beam splitter 32. One light path enters the camera, and the other light path is collected by the light receiving device 34 and transmitted to the spectrometer 36 via the optical fiber 35;

[0046] 5) Analyze and process the image data of the camera 33 and the spectrum data of the spectrometer 36 to obtain oil spill monitoring information.

[0047] In a preferred embodiment, if Figure 2 As shown, the coaxial optical system includes:

[0048] The laser emitting mechanism 1 comprises a laser 11, a beam expander 12 is arranged at the output end of the laser 11, and a semi-transparent semi-reflective prism 13 is arranged on the side of the beam expander 12 away from the laser 11;

[0049] The telescope mechanism 2 is arranged at the output end of the laser emitting mechanism 1, and includes a lens barrel 21, a primary mirror 22 is arranged at the rear end of the lens barrel 21, a light shielding tube 23 is arranged at the front end of the lens barrel 21, a secondary mirror 24 is arranged between the primary mirror 22 and the light shielding tube 23 in the lens barrel 21, and a stepping motor 25 for driving the secondary mirror 24 to move forward and backward along the axial direction of the lens barrel 21;

[0050] The reflected signal receiving mechanism 3 includes a reflector 31, which is arranged on the reflected light path of the semi-transparent and semi-reflective prism 13. A spectroscope 32 is arranged on the reflected light path of the reflector 31. A camera 33 is arranged on one of the spectroscopic paths of the spectroscope 32, and a light receiving device 34 is arranged on the other spectroscopic path. The light receiving device 34 is connected to a spectrometer 36 via an optical fiber 35.

[0051] In this embodiment, a coaxial optical path system is used. At different monitoring distances, there is no need to change the angle between the laser emitting mechanism and the reflected signal receiving mechanism, which is more convenient to use. As the monitoring distance changes, the laser excitation area of ​​the coaxial optical path system and the reflected signal receiving field of view always have a large overlap rate, and the light source utilization rate is high.

[0052] According to the clarity of the image information obtained by the camera 33, the stepper motor 25 drives the secondary mirror 24 to move forward and backward along the axis of the lens barrel 21, realizing automatic focus search, ensuring the signal reception strength, meeting the needs of long-distance transmission, and no need to install a traditional laser ranging system to assist ranging, further reducing the weight of the equipment. The telescope mechanism 2 is used to achieve a higher level of oil spill monitoring, while ensuring accurate monitoring, avoiding the risk of collision with other ships, and having high safety.

[0053] In a preferred embodiment, the coaxial optical system is arranged on an aircraft; the aircraft is a drone, which has mature technology and excellent performance. The coaxial optical system is configured on the aircraft to realize long-distance oil spill monitoring on the sea surface. The coaxial optical path system has a small lateral volume and a reduced weight, which is convenient for drones to carry and realize long-distance monitoring.

[0054] In a preferred embodiment, the wavelength of the pulse laser emitted by the laser 11 is 325-365 nm, which ensures effective excitation of the target 4 to emit a fluorescent signal.

[0055] In a preferred embodiment, if Figure 1 As shown, the camera 33 and the spectrometer 36 are connected to the data processing module via the wireless communication module, and the image data acquired by the camera 33 and the spectral data acquired by the spectrometer 36 are analyzed and processed by the data processing module to obtain oil spill monitoring information.

[0056] In a preferred embodiment, if Figure 1 As shown, a power supply module is provided on the aircraft, and the laser emitting mechanism 1, the telescope mechanism 2 and the reflected signal receiving mechanism 3 are all electrically connected to the power supply module.

[0057] In a preferred embodiment, if Figure 1 As shown, a data storage module is provided on the aircraft, and the camera and the spectrometer are both electrically connected to the data storage module for storing image data acquired by the camera 33 and spectral data acquired by the spectrometer 36 .

[0058] In the description of this specification, the terms "connection", "installation", "fixation" and the like should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0059] In the description of this specification, the description of the terms "one embodiment", "some embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0060] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A non-contact coaxial long-distance water surface oil spill monitoring method, characterized in that: The steps include: 1) Coaxial optical system correction; 11) A CCD camera or a CMOS camera (5) is placed in front of the telescope mechanism (2), and the pulse laser emitted by the laser (11) enters the telescope mechanism (2) through the beam expander (12) and the semi-transparent and semi-reflective prism (13), and is focused on the detection surface of the CCD camera or the CMOS camera (5) through the telescope mechanism (2), forming an image A; 12) Replace the green auxiliary light source (6) and install it in the position of the light receiving device (34), turn on the green auxiliary light source, and the light with a wavelength of 532-562nm is emitted by the green auxiliary light source, enters the telescope mechanism (2) through the reflector (31) and the semi-transparent and semi-reflective prism (13), and is focused on the detection surface of the CCD camera or CMOS camera (5) through the telescope mechanism (2), forming an image B; 13) adjusting the angle of the reflector (31) so that the image A detected by the CCD camera or the CMOS camera (5) overlaps with the image B; 2) acquiring image information of the target to be measured (4) through the camera (33), and controlling the stepping motor (25) to drive the secondary mirror (24) to move according to the clarity of the image information, so as to adjust the position of the secondary mirror (24) so ​​that the focus of the telescope mechanism (2) is positioned on the surface of the target to be measured (4); 3) triggering the laser (11) to emit a pulsed laser, which passes through the beam expander (12) and then through the semi-transparent and semi-reflective prism (13) to enter the telescope mechanism (2) and is focused on the surface of the target to be measured (4); 4) The pulsed laser excites the target to be measured (4) to emit a fluorescence signal. The radiated fluorescence signal passes through the telescope mechanism (2), is reflected by the semi-transparent and semi-reflective prism (13) and the reflector (31), and enters the beam splitter (32). The fluorescence signal is split into two beam splitting paths by the beam splitter (32). One beam splitting path enters the camera (33), and the other beam splitting path is collected by the light receiving device (34) and transmitted to the spectrometer (36) via the optical fiber (35); 5) Analyze and process the image data of the camera (33) and the spectral data of the spectrometer (36) to obtain oil spill monitoring information.

2. The non-contact coaxial long-distance water surface oil spill monitoring method according to claim 1 is characterized in that: The coaxial optical system comprises: A laser emitting mechanism (1) comprises a laser (11), wherein a beam expander (12) is arranged at the output end of the laser (11), and a semi-transparent and semi-reflective prism (13) is arranged on a side of the beam expander (12) away from the laser (11); A telescope mechanism (2) is arranged at the output end of the laser emitting mechanism (1), comprising a lens barrel (21), a primary mirror (22) is arranged at the rear end of the lens barrel (21), a light shielding tube (23) is arranged at the front end of the lens barrel (21), a secondary mirror (24) and a stepping motor (25) for driving the secondary mirror (24) to move forward and backward along the axial direction of the lens barrel (21) are arranged in the lens barrel (21) between the primary mirror (22) and the light shielding tube (23); The reflected signal receiving mechanism (3) comprises a reflector (31), wherein the reflector (31) is arranged on the reflected light path of the semi-transparent and semi-reflective prism (13), a beam splitter (32) is arranged on the reflected light path of the reflector (31), a camera (33) is arranged on one beam splitting path of the beam splitter (32), and a light receiving device (34) is arranged on the other beam splitting path, and the light receiving device (34) is connected to a spectrometer (36) via an optical fiber (35).

3. The non-contact coaxial long-distance water surface oil spill monitoring method according to claim 2 is characterized in that: The coaxial optical system is arranged on an aircraft; the aircraft is a drone.

4. The non-contact coaxial long-distance water surface oil spill monitoring method according to claim 2 is characterized in that: The wavelength of the pulse laser emitted by the laser (11) is 325-365 nm.

5. The non-contact coaxial long-distance water surface oil spill monitoring method according to claim 3 is characterized in that: The camera (33) and the spectrometer (36) are connected to the data processing module via a wireless communication module.

6. The non-contact coaxial long-distance water surface oil spill monitoring method according to claim 3 is characterized in that: The aircraft is provided with a power supply module, and the laser emitting mechanism (1), the telescope mechanism (2) and the reflected signal receiving mechanism (3) are all electrically connected to the power supply module.

7. The non-contact coaxial long-distance water surface oil spill monitoring method according to claim 3 is characterized in that: The aircraft is provided with a data storage module, and the camera (33) and the spectrometer (36) are both electrically connected to the data storage module.

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