Laser radar and view field expansion method thereof

Abstract

The invention is applicable to the field of laser measurement, and particularly relates to a laser radar and a view field expansion method thereof, the laser radar comprises a transmitting device and a receiving device, the transmitting device is used for transmitting probe light to scan a to-be-measured target, the receiving device is used for receiving target light reflected after the probe light scans the to-be-measured target, and the receiving device is used for receiving the target light. The laser radar is used for receiving target light and converting and processing the received target light so as to detect a to-be-detected target, and the laser radar further comprises an adjusting device. The adjusting device comprises an adjusting space and a second medium contained in the adjusting space, the transmitting device is immersed in the second medium, or the receiving device is immersed in the second medium, or the transmitting device and the receiving device are both immersed in the second medium; according to the invention, the adjusting device is arranged, and the refraction principle of light in different media is utilized, so that the field of view of the laser radar for scanning the to-be-measured target under the same condition is larger.

Description

Technical Field

[0001] The invention belongs to the field of laser measurement, and in particular relates to a laser radar and a method for expanding the field of view thereof. Background Art

[0002] LiDAR is a remote sensing technology that uses lasers to perform three-dimensional detection. The distance detection usually uses the time of flight (TOF) method, that is, using pulsed lasers to calculate the longitudinal distance of an object by recording the time difference between the transmitted pulse and the received pulse. As for the detection of the detection beam on a two-dimensional plane, the current common method usually uses hybrid solid-state methods such as rotating multi-faceted prisms, MEMS (micro-electromechanical systems) galvanometer scanning, and digital micro-mirror array (digital micro-mirror device, DMD) scanning.

[0003] However, the field of view of these hybrid solid-state methods is limited. In order to improve the field of view, a multi-system splicing method is usually used, which makes the cost and complexity of the spliced ​​multi-system higher. Summary of the invention

[0004] The purpose of an embodiment of the present invention is to provide a laser radar, aiming to solve the problem that existing laser detection equipment uses a multi-system splicing method to increase the field of view, which makes the cost and complexity of the spliced ​​multi-system higher.

[0005] The embodiment of the present invention is implemented as follows: a laser radar, the laser radar includes a transmitting device and a receiving device, the transmitting device is used to transmit detection light to scan the target to be measured, the receiving device is used to receive the target light reflected after the detection light scans the target to be measured, and convert and process the received target light to achieve detection of the target to be measured, the laser radar also includes: an adjustment device;

[0006] The regulating device comprises a regulating space and a second medium contained in the regulating space.

[0007] The emitting device is immersed in the second medium,

[0008] Alternatively, the receiving device is immersed in the second medium,

[0009] Alternatively, the transmitting device and the receiving device are both immersed in the second medium;

[0010] The refractive index of the second medium to light is greater than the refractive index of the first medium in the environment where the target to be measured is located, so that the field of view of the laser radar scanning the target to be measured can be expanded through the second medium.

[0011] Another object of an embodiment of the present invention is to provide a method for expanding the field of view of a laser radar, which is used for the above-mentioned laser radar, and the method comprises the following steps:

[0012] Selecting the second medium according to the environmental parameters of the target to be measured, and then determining the refractive index of the second medium;

[0013] The laser radar is arranged in the adjustment space of the adjustment device and immersed in the second medium;

[0014] The detection light or target light of the laser radar is refracted by the second medium to expand the field of view of the laser radar scanning the target to be measured.

[0015] A laser radar provided in an embodiment of the present invention, compared with a conventional laser radar, uses an adjustment device to utilize the refraction principle of light in different media, so that under the same conditions, the laser radar has a larger field of view when scanning the target to be measured; there is no need to splice multiple systems, the structure is relatively simple, and the cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the structure of a laser radar provided by an embodiment of the present invention;

[0017] Figure 2 A schematic diagram of a principle for expanding the field of view provided by an embodiment of the present invention;

[0018] Figure 3 A schematic diagram of the propagation of detection light of a laser radar in different media provided by an embodiment of the present invention;

[0019] Figure 4 A schematic diagram of light propagation in different media in one embodiment;

[0020] Figure 5 A schematic diagram of the structure of another laser radar provided by an embodiment of the present invention;

[0021] Figure 6 A schematic flow chart of a method for expanding the field of view of a laser radar provided in an embodiment of the present invention.

[0022] In the attached drawings: 10 - laser radar; 100 - transmitting device; 101 - laser; 102 - reflecting element; 103 - rotating mirror; 104 - receiving device; 1041 - detector; 1042 - receiving lens; 105 - laser optical fiber; 106 - collimating element; 200 - adjusting device. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0024] It can be understood that the terms "first", "second", etc. used in the present application can be used in this article to describe various elements, but unless otherwise specified, these elements are not limited by these terms. These terms are only used to distinguish the first element from another element.

[0025] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0026] like Figure 1 As shown, it is a structural diagram of a laser radar 10 provided by an embodiment of the present invention, comprising: a transmitting device 100 and a receiving device 104, wherein the transmitting device 100 is used to transmit detection light to scan the target to be measured, and the receiving device 104 is used to receive the target light reflected after the detection light scans the target to be measured, and convert and process the received target light to achieve detection of the target to be measured, and the laser radar 10 also includes: an adjusting device 200;

[0027] The regulating device 200 includes a regulating space and a second medium contained in the regulating space.

[0028] The emitting device 100 is immersed in the second medium.

[0029] Alternatively, the receiving device 104 is immersed in the second medium,

[0030] Alternatively, the transmitting device 100 and the receiving device 104 are both immersed in the second medium;

[0031] The refractive index of the second medium to light is greater than the refractive index of the first medium in the environment where the target to be measured is located, so that the field of view of the laser radar 10 scanning the target to be measured can be expanded through the second medium.

[0032] In this embodiment, the adjustment device 200 is set up so that the detection light of the laser radar 10, during the propagation process, enters from the medium on the side with a high refractive index to the medium on the side with a low refractive index, and refracts with a larger refractive angle. The refracted light is irradiated to the target to be measured, thereby expanding the field of view; or, after the detection light is reflected by the target to be measured, it enters from the side with a low refractive index to the medium on the side with a high refractive index, and refracts with a smaller refractive angle. The refracted target light is received by the receiving device 104, thereby expanding the field of view; that is, by utilizing the principle of refraction of light in different media, the laser radar 10 has a larger field of view when scanning the target to be measured under the same conditions; there is no need to splice multiple systems, the structure is relatively simple, and the cost is relatively low.

[0033] like Figure 4 FIG. 1 is a schematic diagram of light propagation in different media in one embodiment. When light is incident from a first medium to a second medium, the relationship between the incident angle i1 and the refraction angle i2 satisfies Snell's law, as shown in the following formula:

[0034] n1sin i1=n2sin i2

[0035] Where n1 and n2 are the refractive indices of the first medium and the second medium, respectively; therefore, if n1<n2, then i1>i2; if n1>n2, then i1<i2. It can be seen that in order to expand the field of view of the laser radar 10, it is necessary to place the laser radar 10 in a high refractive index medium and use the refraction of light to enlarge the field of view; it can be seen that in this embodiment, without modifying the transmitting device 100 of the laser radar 10, the field of view of the laser radar 10 can be expanded by simply setting the adjustment device 200. The structure is simple and the cost is low, and it can be applied not only to the distance measurement of objects, but also to some aspects that require a large field of view, such as detecting the shape, size and size of objects. In addition, when the field of view requirement is certain, by setting the above-mentioned adjustment device 200, the miniaturized size design of the transmitting device 100 or the receiving device 104 can be achieved while ensuring the field of view requirement, thereby reducing the size and weight of the laser radar 10, and facilitating the expansion of the application scenarios of the laser radar 10, such as unmanned vehicles, new energy electric vehicles or navigation equipment, etc., and the present embodiment is not limited to this.

[0036] In addition, when the laser radar 10 is used in scenes other than distance measurement, such as measuring the shape and size of an object, the adjustment device 200 can also be used to expand the field of view, thereby improving the detection effect of the laser radar 10. In this embodiment, the field of view, which can also be called the field of view angle, generally refers to the range of the sky that can be seen by a telescope or binoculars; the field of view represents the maximum range that the lens can observe, usually expressed as an angle, the larger the field of view, the larger the observation range. For example, the field of view of some cameras is 50°, while some are 58°. The latter can capture a larger range of scenery at the same distance compared to the former. The field of view of general cameras is around 52°, and some can even reach 180° or 360° (the camera base is fixed and the lens can rotate one circle), which is not limited here.

[0037] Therefore, it can be seen from the above that the transmitting device 100 or the receiving device 104 in this embodiment is rotatable, and the adjusting device 200 can cooperate with the rotatable transmitting device 100 or the receiving device 104 to further improve the field of view of the laser radar 10 at the same distance.

[0038] In the first example of this embodiment, the transmitting device 100 transmits detection light to illuminate the target to be measured, and the receiving device 104 receives the target light reflected by the target to be measured, so as to detect the distance of the target to be measured; the transmitting device 100 is immersed in the second medium, and the receiving device 104 is not immersed in the second medium (not shown in the figure); in this case, the receiving device 104 is arranged outside the adjustment space of the adjustment device 200, so that the receiving device 104 can receive the target light reflected by the target to be measured, and the detection light of the transmitting device 100 can be refracted during the propagation of the second medium and the first medium, thereby expanding the field of view of the detection light scanning the target to be measured.

[0039] In the second example of this embodiment, the transmitting device 100 is not immersed in the second medium (not shown in the figure), and the receiving device 104 is immersed in the second medium; in this way, after the detection light is reflected by the target to be measured, it enters the medium on the side with a high refractive index from the side with a low refractive index, and refracts with a smaller refraction angle. The refracted target light is received by the receiving device 104. Under the same field of view conditions, the receiving surface of the receiving device 104 for receiving the target light is smaller, and then the corresponding field of view is larger under the same receiving surface condition, thereby realizing the expansion of the field of view of the laser radar 10.

[0040] In the third example of this embodiment, the transmitting device 100 and the receiving device 104 are both immersed in the second medium; while achieving an expanded field of view, it is also convenient to conveniently set the transmitting device 100 and the receiving device 104, and the structure is simple and compact. Figure 1 shown.

[0041] Similarly, the transmitting device 100 and the receiving device 104 may not be completely immersed in the second medium. It is only necessary to ensure that the detection light path emitted by the transmitting device 100 and the target light path received by the receiving device 104 are in the second medium. In this way, the refraction of the detection light and the target light is achieved, thereby expanding the field of view. As for how to set and fix the transmitting device 100 or the receiving device 104 through the above-mentioned shell, it is not limited here.

[0042] In the fourth example of this embodiment, the conversion and processing of the received target light is divided into: converting the target light, that is, using the detector 1041 included in the receiving device 104 to convert the target light into an electrical signal, and the electrical signals corresponding to target lights of different intensities are different, and processing the converted electrical signal, that is, using the back-end equipment (a computer with relevant programs preset) matched with the detector 1041 to digitally calculate the electrical signal to obtain the distance between the laser radar 10 and the target to be measured; the first medium can be air in a natural environment, and the default refractive index of air to light is a reference value of about 1; then the ratio of the refractive index of the second medium to the reference value is greater than 1, and the second medium can be a liquid with a refractive index greater than that of air, or a gas with a refractive index greater than that of air; it should be noted that Figure 1 The solid line in the middle represents the emitted light (also called the detection light or the incident light), and the dotted line represents the received light (also called the target light).

[0043] In the fifth example of this embodiment, the adjustment device 200 includes a shell, and an adjustment space is provided in the shell for accommodating the second medium. One side of the shell is set to be open or light-transmissive, so that the detection light or the target light can pass through the surface. A supporting fixture, such as a supporting frame, a limiting frame or a clamp, is provided in the shell for detachably fixing the transmitting device 100 and the receiving device 104; so that the transmitting device 100 and the receiving device 104 can be immersed in the second medium.

[0044] Preferably, the shell can be made of a material that is anti-electromagnetic interference, such as tin, so that during the operation of the laser radar 10, it can effectively prevent interference from the external environment and affect the detection accuracy; it can also be made of a material with high thermal conductivity, so as to quickly conduct the heat generated during the operation of the laser radar 10 and improve the detection accuracy.

[0045] In order to maintain the continuous and stable transmission of the detection light and the target light by the second medium, in the sixth example of this embodiment, a temperature control device (not shown in the figure) is arranged outside the shell, and the temperature control device is used to control the temperature of the second medium to be within a set temperature range; the temperature control device may include an electric heat pump, a pipeline and a heat exchanger, and a heat exchange cavity is arranged on the outer ring of the shell, and the heat exchange cavity is connected with the heat exchanger to form a heat exchange loop, and the electric heat pump is connected with the heat exchanger through the pipeline to form a temperature control loop, and the heat exchange loop and the temperature control loop exchange heat in the heat exchanger to achieve temperature control of the heat exchange cavity and the second medium in the shell; the heat exchanger may be a commercially available plate heat exchanger, and the control device may also be a conventional fan, which is an air-cooled structure composed of an electric heating wire.

[0046] The temperature control device provided in this embodiment can ensure the stability of light propagation by the second medium on the one hand, and can maintain the temperature difference between the first medium and the second medium at a small value on the other hand, so as to avoid the detection of the target being affected by the temperature; on the other hand, the temperature control device can make the laser radar 10 applicable to some areas with lower temperatures, such as Jilin, Changchun and other areas in the northeast region.

[0047] like Figure 1 As shown, in one embodiment, the second medium is liquid or gas, and preferably, the second medium is cedar oil.

[0048] In this embodiment, by setting the cedar oil (i.e. Figure 2 The medium #2 can also be used as a second medium), and the field of view of the laser radar 10 is expanded by using the principle of light refraction; Figure 2 , Figure 3 As shown, the refraction principle of cedar oil on light is as follows: in the optical system, medium #1 is usually air, which can also be recorded as the first medium. The refractive index of cedar oil is n=1.515. If the original field of view of the laser radar 10 is 60° and its half field of view ω=30°, then the half field of view ω′ after immersion in cedar oil satisfies the following formula:

[0049] n sinω=n′sinω′

[0050] Available The expanded field of view is 98°, which is 1.6 times larger than the original field of view of 60°. The effect of expanding the field of view is significant, and the setting difficulty is low and the cost is not high.

[0051] In an example of this embodiment, the liquid may be water, whose refractive index is 1.33, or liquid carbon dioxide, whose refractive index is 1.20; the second medium may be a gas, for example, sulfur hexafluoride, which is physiologically inactive and pharmacologically considered an inert gas. The refractive index of sulfur hexafluoride is slightly greater than 1, and it has good insulation properties.

[0052] like Figure 1 As shown, in one embodiment, the transmitting device 100 includes at least a laser light source, and a rotating mirror 103 is arranged on the optical path of the detection light emitted by the laser light source, and the rotating mirror 103 is rotatable. The rotation of the rotating mirror 103 is used to reflect the detection light toward the target to be measured for scanning.

[0053] In this embodiment, the detection light emitted by the laser light source can be reflected toward the target to be measured by setting a rotating mirror 103, and during the rotation of the rotating mirror 103, the angle of the detection light reflected toward the target to be measured is changed differently to achieve full coverage within the field of view, thereby achieving accurate detection of the target to be measured.

[0054] In an example of the present embodiment, the rotating mirror 103 may also be a multi-faceted reflecting prism, and the detection light path emitted by the laser light source may be the detection light path emitted directly from the light emitting surface of the laser light source, or may be the detection light path emitted after being adjusted by an optical element; the rotating mirror 103 is provided with a rotating shaft, and the rotating shaft is arranged on the adjustment space or the external support frame through a bearing, and one end of the rotating shaft is connected to a motor, and the rotating shaft and the rotating mirror are driven to rotate by the motor. The rotating mirror 103 has a plurality of reflecting surfaces, and the plurality of reflecting surfaces may be an even number or an odd number. For the convenience of calculating or converting conventional angles, it is preferably set to an even number, for example: 10, 12 or 8. When the number of the reflecting surfaces is 12 (a, b, c, ..., k, l), the reflecting surfaces are arranged on the outer peripheral surface of the rotating mirror 103; specifically, the number of reflecting surfaces is n, such as Figure 1As shown, the rotating mirror 103 rotates around its central axis, and each of the reflection surfaces therein will reflect the detection light emitted by the transmitting device 100; every time the angle of rotation is 360° / n, the light is irradiated onto the next adjacent reflection surface, and the angle of deflection of the reflected light is 2*360° / n, which is the maximum field of view of the laser radar 10 based on the rotating mirror 103. When n is 12, the scanning of the rotating mirror 103 is based on the reflection principle of light, that is, the reflection angle is equal to the incident angle, and the light is incident on the reflection surface. When the reflection surface rotates by 30°, the reflected light will be deflected by 60°.

[0055] In another example of this embodiment, the laser light source includes a laser 101 , a laser optical fiber 105 or a collimator 106 , and the collimator 106 is disposed on the optical path of the detection light emitted by the laser 101 or the laser optical fiber 105 .

[0056] Specifically, the laser light source may be a laser 101 for emitting pulsed laser light of a certain wavelength as detection light.

[0057] like Figure 5 As shown, the laser light source includes a laser fiber 105 and a collimator 106. The laser fiber 105 is used to emit a pulse laser of a certain wavelength. The collimator 106 is arranged at the end of the laser fiber 105 to collimate the pulse laser and transmit the pulse laser to the rotating mirror 103 to form a detection light. The collimator 106 can be a collimator, a beam combiner, or other lenses with a converging effect. This embodiment is not limited to this.

[0058] like Figure 1 As shown, in one embodiment, the emitting device 100 further includes a reflector 102 , which is tiltedly disposed on the optical path of the detection light, and a reflective surface of the reflector 102 faces the laser light source and the rotating mirror 103 .

[0059] In this embodiment, when the reflective surface of the reflector 102 has the same inclination angle toward the laser light source and the rotating mirror 103, the detection light and the target light are in a coaxial state of transmission and reception, which makes it easier to fix the transmitting device 100 and the receiving device 104 and reduces the difficulty of setting. At the same time, the number of rotating mirrors 103 can be reduced, and the detection light and the target light can be adjusted simultaneously by one rotating mirror 103.

[0060] In an example of this embodiment, the reflective element 102 adopts a small reflective mirror, and the size of the small reflective mirror is relatively small. The specific size can be flexibly set according to the specifications of the rotating mirror 103. This embodiment does not impose too many restrictions, and technical personnel in this field can make conventional choices based on the content of this embodiment.

[0061] In another example of this embodiment, the inclination angles of the reflective surface of the reflector 102 toward the laser light source and the rotating mirror 103 may be different. The reflector 102 is arranged to guide the detection light emitted by the laser 101 to the rotating mirror 103. The detection light guided to the rotating mirror 103 may be on the same reflection surface as the target light at the same time, or may not be on the same reflection surface at the same time. For example, when the detection light is reflected by the reflection surface b, the target light may be reflected by the reflection surface a.

[0062] like Figure 1 As shown, in one embodiment, the receiving device 104 and the transmitting device 100 share the rotating mirror 103 .

[0063] In this embodiment, by sharing the rotating mirror 103, the detection light and the target light can both be reflected, and the scanning and detection of the target to be detected can be achieved by cooperating with the transmitting device 100 and the receiving device 104. Providing the rotating mirror 103 can also reduce the modulation difficulty of the transmitting device 100 and the receiving device 104, and also make the structure more compact when the transmitting device 100 and the receiving device 104 are fixed, thereby reducing the equipment cost.

[0064] In an example of this embodiment, the receiving device 104 and the transmitting device 100 are both immersed in the second medium, and when the field of view of the transmitting device 100 is expanded, the field of view of the receiving device 104 is also expanded.

[0065] like Figure 1 , Figure 5 As shown, in another embodiment, the receiving device 104 includes a receiving component and a detector 1041, the receiving component is used to receive the target light, and transmit the target light to the detector 1041 after converging, and the detector 1041 is arranged on the light output side of the receiving component, and is used to convert and process the received target light.

[0066] In this embodiment, the receiving component can be a receiving lens 1042, or a lens module composed of multiple lenses, or a lens structure with a converging effect; by setting the receiving component, the target light can be better received and converged, and then transmitted to the detector 1041. The detector 1041 can be one of a photodiode, a photomultiplier tube or an avalanche photodiode, which is not limited here.

[0067] like Figure 6 As shown, in another embodiment, a method for expanding the field of view of a laser radar is used for the laser radar 10 as described above, and the method includes the following steps:

[0068] Step S102: selecting the second medium according to the environmental parameters of the target to be measured, and then determining the refractive index of the second medium;

[0069] Step S104: placing the laser radar 10 in the adjustment space of the adjustment device 200 and immersing it in the second medium;

[0070] Step S106: refracting the detection light or target light of the laser radar 10 through the second medium to expand the field of view of the laser radar 10 scanning the target to be measured.

[0071] In this embodiment, the detection light emitted by the transmitting device 100 is refracted by the second medium, thereby expanding the field of view of the laser radar 10; similarly, the target light to be received by the receiving device 104 is refracted by the second medium, thereby indirectly expanding the field of view of the laser radar 10.

[0072] In one example, the adjustment space can be formed by the above-mentioned shell setting, and the environmental parameters of the target to be measured in step S102 refer to: the refractive index of the first medium in the environment where the target to be measured is located, mainly selecting the second medium based on the refractive index of the first medium, and placing the second medium in the adjustment space after it is selected; in order to further improve the detection accuracy of the laser radar 10, preferably, the environmental parameters may also include parameters such as temperature and humidity, so as to further make the parameters of the first and second media other than the refractive index the same, thereby improving the accuracy and effect of detection.

[0073] In step S104, a support frame, a fixed frame or a fixed bayonet, etc., which can fix the transmitting device 100 or the receiving device 104, is preset in the adjustment space, so that the transmitting device 100 or the receiving device 104 can be fixed conveniently, and the support frame, the fixed frame or the fixed bayonet, etc. does not affect the propagation of the detection light and the target light.

[0074] In one example, steps S102 and S104 may be pre-set, for example: the conventional first medium is air, and the second medium is cedar oil, and the refractive index of the cedar oil relative to air is 1.515. Figure 2 As shown, if the original field of view of the laser radar 10 is 60°, and its half field of view ω=30°, then the half field of view ω′ after immersion in cedar oil satisfies:

[0075] n sinω=n′sinω′

[0076] but The expanded field of view is 98°, which is expanded by 1.6 times. Without adjusting the hardware parameters of the laser radar 10, its detection field of view is also larger.

[0077] In one embodiment, the step of placing the laser radar 10 in the adjustment space of the adjustment device 200 includes the following steps:

[0078] Immersing the emitting device 100 in the second medium,

[0079] Alternatively, the receiving device 104 is immersed in the second medium,

[0080] Alternatively, both the transmitting device 100 and the receiving device 104 are immersed in the second medium.

[0081] like Figure 1 As shown, the transmitting device 100 and the receiving device 104 are both immersed in the second medium, and the transmitting device 100 and the receiving device 104 are arranged in a coaxial manner, so that the detection field of view of the laser radar 10 is larger, the structure is more compact, and it is more convenient to fix and replace the transmitting device 100 and the receiving device 104. Similarly, if one of the transmitting device 100 and the receiving device 104 is immersed in the second medium, the field of view can also be expanded; no further details are given here.

[0082] In one embodiment, the refractive index of the first medium in the environment where the target to be measured is located is n', and the refractive index of the second medium to light is n, wherein n / n'>1.

[0083] In this embodiment, the second medium may be cedar oil, and the first medium is air, n / n'=1.515. Light incident from the second medium into the first medium will be refracted, thereby expanding the field of view. The detection light emitted by the transmitting device 100 is refracted by the second medium, thereby expanding the field of view of the laser radar 10. The second medium may also be some liquids with high refractive index, such as pure water, ethanol aqueous solution or sucrose aqueous solution and other non-electrolyte liquids, which have the advantages of non-conductivity and high refractive index. Cedar oil is preferably used, which is commonly used in some optical systems and is more convenient to use.

[0084] A laser radar 10 is provided in the above-mentioned embodiment of the present invention, and a method for expanding the field of view of the laser radar is provided based on the laser radar 10. By setting an adjustment device 200, the second medium of the adjustment space is coordinated with the first medium of the environment where the target to be measured is located to form two medium propagation spaces with different refractive indices. The principle of refraction of light in different media is utilized to make the laser radar 10 have a larger field of view when scanning the target to be measured under the same conditions (same light intensity and distance between phases).

[0085] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A laser radar, comprising a transmitting device and a receiving device, wherein the transmitting device is used to transmit detection light to scan a target to be measured, and the receiving device is used to receive target light reflected after the detection light scans the target to be measured, and convert and process the received target light to achieve detection of the target to be measured, characterized in that: The laser radar further comprises: an adjustment device; The regulating device comprises a regulating space and a second medium contained in the regulating space. The emitting device is immersed in the second medium, Alternatively, the receiving device is immersed in the second medium, Alternatively, the transmitting device and the receiving device are both immersed in the second medium; The refractive index of the second medium to light is greater than the refractive index of the first medium in the environment where the target to be measured is located, so that the field of view of the laser radar scanning the target to be measured can be expanded through the second medium.

2. The laser radar according to claim 1, characterized in that: The second medium is gas or liquid.

3. The laser radar according to claim 2, characterized in that: The second medium is cedar oil.

4. The laser radar according to claim 1, characterized in that: The transmitting device at least comprises a laser light source, and a rotating mirror is arranged on the optical path of the detection light emitted by the laser light source, and the rotating mirror is rotatably arranged, and the detection light is reflected toward the target to be measured for scanning by rotating the rotating mirror.

5. The laser radar according to claim 4, characterized in that: The emitting device further comprises a reflector, which is arranged obliquely on the optical path of the detection light, and a reflective surface of the reflector faces the laser light source and the rotating mirror.

6. The laser radar according to claim 4 or 5, characterized in that: The laser light source comprises a laser or a laser optical fiber, and a collimating component arranged on the optical path of the detection light emitted by the laser or the laser optical fiber.

7. The laser radar according to claim 4 or 5, characterized in that: The receiving device and the transmitting device share the rotating mirror.

8. A method for expanding the field of view of a laser radar, used for the laser radar as claimed in any one of claims 1 to 7, characterized in that: The method comprises the following steps: Selecting the second medium according to the environmental parameters of the target to be measured, and then determining the refractive index of the second medium; The laser radar is arranged in the adjustment space of the adjustment device and immersed in the second medium; The detection light or target light of the laser radar is refracted by the second medium to expand the field of view of the laser radar scanning the target to be measured.

9. The method for expanding the field of view of a laser radar according to claim 8, characterized in that: The step of arranging the laser radar in the adjustment space of the adjustment device comprises the following steps: immersing the transmitting device in the second medium, Alternatively, the receiving device is immersed in the second medium, Alternatively, both the transmitting device and the receiving device are immersed in the second medium.

10. The method for expanding the field of view of a laser radar according to claim 8, characterized in that: The refractive index of the first medium in the environment where the target to be measured is located is n', and the refractive index of the second medium to light is n, wherein n / n'>1.

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