Lidar test device and method

Abstract

The present invention provides a LiDAR test method comprising the steps of: preparing a device under test; arranging a photometer in a direction of orientation of the device under test; measuring light of a test environment by using the photometer, and performing a performance test on the device under test; and recording at least one of the measured light of the test environment, performance of the device under test, and an influence caused by the light of the test environment. The LiDAR test method according to the present invention enables creation of a test environment under various conditions and precise measurement of performance of a device under test.

Description

LIDAR test device and method

[0001] The present invention relates to a method and apparatus for testing the performance of a LiDAR device. More specifically, it relates to an apparatus and method for testing the performance of a LiDAR device in a specific ambient light environment and the specific performance of a LiDAR device.

[0002] LiDAR devices have been continuously evolving alongside the development of electric vehicles and autonomous driving technologies. LiDAR devices utilize light to detect surrounding objects and calculate point clouds based on data collected using light.

[0003] As LiDAR devices are utilized in electric vehicles and autonomous driving technologies, their precise performance is a critical factor in terms of the completeness and stability of autonomous driving technology. Therefore, there is a need to measure and verify the performance of LiDAR devices in various environments.

[0004] Since LiDAR devices detect objects using light, noise and performance degradation may occur due to the influence of the external environment and external light. In the fields of autonomous driving and automotive sensing, where precise measurements are required, accurate performance measurement of sensing devices is necessary; however, due to the influence of ambient light and the external environment, performance measurements may be inconsistent or difficult to obtain accurately.

[0005] Furthermore, when conducting performance tests on LiDAR devices in an indoor environment, accurate measurement of actual performance may be difficult because the tests are performed under conditions different from those in an actual outdoor environment. For example, while light interference caused by sunlight may occur in outdoor environments, it may be absent or extremely minimal in indoor environments. Consequently, there may be a difference between the performance measured during testing and the actual performance in an outdoor environment.

[0006] Accordingly, there has been a demand for methods and devices to accurately evaluate performance even when external optical interference is present in the actual operating environment of LiDAR. Furthermore, there has been a demand for methods to evaluate the impact of such external optical interference on the performance of LiDAR devices.

[0007] [Prior Art Literature]

[0008] [Patent Literature]

[0009] Korean Published Patent Application No. 10-2022-0025872 (March 3, 2023)

[0010] The present invention has been devised in consideration of the above-mentioned purpose, and the objective of the present invention is to provide a method and apparatus for testing the performance of a LiDAR device.

[0011] Furthermore, the objective of the present invention is to provide a method and apparatus for measuring and controlling ambient light to test the performance of a LiDAR device. Additionally, the objective of the present invention is to provide a method and apparatus for testing a LiDAR by creating an indoor environment with conditions similar to the actual operating environment of the LiDAR device (e.g., an environment where light interference caused by sunlight occurs).

[0012] The problems to be solved in the embodiments of the present invention are not limited thereto, and may also include objectives or effects that can be identified from the means for solving the problems or embodiments described below.

[0013] A method for testing a LiDAR device to solve the problem presented in the present invention may include: a step of preparing a device to be tested; a step of placing a light measuring instrument in the orientation of the device to be tested; a step of measuring light in a test environment with the light measuring instrument and performing a performance test of the device to be tested; and a step of recording at least one of the measured light in the test environment, the performance of the device to be tested, and the influence of the light in the test environment.

[0014] In addition, the method according to the present invention may further include the step of placing a LiDAR auxiliary light source.

[0015] In addition, the auxiliary light emitted by the above auxiliary light source may have a wavelength band corresponding to the optical wavelength band of the optical receiver and optical transmitter of the device to be inspected.

[0016] And, the step of arranging the auxiliary light source may include the step of controlling the auxiliary light emitted from the auxiliary light source.

[0017] In addition, the above auxiliary light can be adjusted based on the radiant intensity of sunlight.

[0018] In addition, the intensity of the above auxiliary light can be adjusted according to wavelength band.

[0019] In addition, the light measuring instrument can measure light of a wavelength corresponding to the wavelength band of the bandpass filter of the light receiver of the device under inspection.

[0020] And, the above light measuring instrument is W / m 2 Radiant illuminance expressed as can be measured.

[0021] The LiDAR test device and method according to the present invention can inspect the specific performance of a LiDAR device and calculate the performance of the LiDAR device as a numerical value.

[0022] In addition, the LiDAR test device and method according to the present invention can measure and control ambient light to test the performance of a LiDAR device. Furthermore, by artificially irradiating an external light onto a LiDAR receiver (Rx) through a light source that emits auxiliary light, the performance of the LiDAR device can be compared when external light is present and when it is absent.

[0023] In addition, the LiDAR test device and method according to the present invention can perform performance tests on the LiDAR in an actual operating environment by establishing an environment similar to the actual external environment (e.g., a road environment where light interference caused by sunlight occurs) even in an internal test environment.

[0024] FIG. 1 is a schematic diagram illustrating the operation of a LiDAR device and / or a device to be inspected, including a light emitter (Tx) and a light detector (Rx) to which the present invention is applied.

[0025] FIG. 2 is a drawing for explaining the arrangement of a target and an auxiliary light source emitting auxiliary light according to an embodiment of the present invention.

[0026] FIG. 3a is a diagram illustrating the irradiation of auxiliary light to a photodetector of a device to be inspected according to one embodiment of the present invention.

[0027] FIG. 3b is a drawing illustrating that auxiliary light is not irradiated to the photodetector of a device to be inspected according to one embodiment of the present invention.

[0028] Figure 4 is a diagram illustrating the radiant intensity of sunlight in an external environment.

[0029] FIG. 5 is a diagram illustrating an environment for inspecting a LiDAR device according to one embodiment of the present invention.

[0030] FIG. 6a is a diagram illustrating illuminance measurement using a light measuring instrument in an environment for inspecting a LiDAR device according to one embodiment of the present invention.

[0031] FIG. 6b is a diagram illustrating the arrangement of a LiDAR device and a light measuring instrument in an environment for inspecting a LiDAR device according to an embodiment of the present invention.

[0032] FIG. 7 is a top view illustrating the arrangement of a LiDAR device and a light measuring instrument according to an embodiment of the present invention.

[0033] FIG. 8a is a top view illustrating the arrangement of a LiDAR device and a light measuring instrument according to one embodiment of the present invention.

[0034] FIG. 8b is a top view illustrating the arrangement of the LiDAR device and the optical measuring instrument according to FIG. 8a.

[0035] FIG. 9a is a diagram illustrating how auxiliary light is irradiated onto a light receiver in a test device.

[0036] FIG. 9b is a drawing to explain that in the test device of FIG. 9a, the device to be tested rotates so that the auxiliary light is not irradiated onto the light receiver.

[0037] FIG. 10a is a test apparatus of FIG. 9a, wherein the device to be tested is exposed to optical interference according to the azimuth angle. This is a drawing to explain the state rotated by the azimuth angle.

[0038] FIG. 10b is a test apparatus of FIG. 9b, wherein the device to be tested measures optical interference according to the azimuth angle. This is a drawing to explain the state rotated by the azimuth angle.

[0039] FIG. 11a is a diagram illustrating how an auxiliary light is irradiated onto a light receiver in a test device.

[0040] FIG. 11b is a drawing for explaining that in the test device of FIG. 11a, the device to be tested rotates so that the auxiliary light is not irradiated onto the light receiver.

[0041] FIG. 12a describes the test apparatus of FIG. 11a, wherein the device to be tested is exposed to optical interference according to the elevation angle. This is a drawing to explain the state rotated at an elevation angle.

[0042] FIG. 12b is a test device for measuring optical interference of FIG. 11b, wherein the device to be tested is exposed to optical interference according to the elevation angle. This is a drawing to explain the state rotated at an elevation angle.

[0043] FIG. 13 is a diagram illustrating the operation of a LiDAR test device according to one embodiment of the present invention.

[0044] FIG. 14 is a diagram illustrating the operation of optical interference measurement according to the elevation angle of a LiDAR test device according to one embodiment of the present invention.

[0045] FIG. 15 is a diagram illustrating the operation of optical interference measurement according to the azimuth angle of a LiDAR test device according to one embodiment of the present invention.

[0046] FIG. 16 is a flowchart illustrating a LiDAR test method according to one embodiment of the present invention.

[0047] The following detailed description of the invention refers to the accompanying drawings, which illustrate specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It should be understood that various embodiments of the invention are different but need not be mutually exclusive. For example, specific shapes, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in relation to one embodiment.

[0048] Terms containing ordinal numbers, such as first, second, etc., may be used to describe various components, but the components are not limited by these terms. Terms may be used for the purpose of distinguishing one component from another. For example, it should be understood that a first component may be named a second component, and conversely, a second component may be named a first component.

[0049] Furthermore, it should be understood that the location or arrangement of individual components within each disclosed embodiment may be changed without departing from the spirit and scope of the invention. Accordingly, the following detailed description is not intended to be taken in a limiting sense, and the scope of the invention is limited only by the appended claims, including all equivalents thereof, provided appropriately described. Similar reference numerals in the drawings refer to the same or similar functions across various aspects.

[0050] FIG. 1 is a schematic diagram illustrating the operation of a LiDAR device and / or a device to be inspected, including a light emitter (Tx) and a light detector (Rx) to which the present invention is applied.

[0051] Referring to FIG. 1, the inspection target device (LiDAR device) (10) to which the present invention is applied to conduct a test may include a light emitter (11) for emitting light, a light detector (12) for detecting that the emitted light is reflected back from an object (20), and an optical device (13) provided in a light path to which the light emitted from the light emitter (11) is received by the light detector (12).

[0052] Here, the light emitter (11) may be a diode and a laser light source, but is not limited thereto. The inspection target device, which is a LiDAR device, can calculate the range or property of the object (20) using the reflected light that is reflected back from the object (20).

[0053] Additionally, although the optical device (13) is shown as a single block, it may include optical devices corresponding to a light emitter and a light detector, respectively. Specifically, there may be an optical device on the light emitter side for transmitting light emitted from the light emitter and adjusting the path of the emitted light, and an optical device for adjusting the path of the reflected light that is reflected back from the object and transmitting it to the light detector.

[0054] Additionally, the optical device (13) may include an optical device or a bandpass filter that concentrates light received from the outside. For example, an optical device mounted or positioned on the side of the photodetector may include a bandpass filter corresponding to the wavelength band of light sensed by the light sensor included in the photodetector. That is, the bandpass filter included in the photodetector can filter the light reflected back from the object so that it corresponds to the wavelength band of light sensed by the light sensor of the photodetector. As a result, the wavelength band of the light passing through the bandpass filter and incident on the light sensor of the photodetector may be constant or uniform.

[0055] In this specification, the device under test (DUT) may be interchangeably referred to as a LiDAR device.

[0056] In the present invention, a point cloud may refer to a set of data points in 3D space. A set of data points calculated by a LiDAR device to which the present invention is applied may also be referred to as a point cloud. Since the distances between data points constituting a point cloud are generally non-uniform, it is desirable to specifically encode all three coordinates (orthogonal coordinates or spherical coordinates) for each point.

[0057] Meanwhile, a cloud point may refer to a data point generated by a LiDAR device.

[0058] According to the present invention, the device subject to inspection may be referred to as the device under test (DUT).

[0059] In the present invention, among results where the measured value is positive, the case where the measured value is accurate—that is, the case where both the measured value and the result are positive—is referred to as a true positive (TP). Among results where the measured value is positive, the case where the measured value is inaccurate—that is, the case where the measured value is positive but the result is negative—is referred to as a false positive (FP).

[0060] In the present invention, the probability of valid points in a single measurement and / or a plurality of accumulated measurements for a single object is referred to as the probability of detection (PoD) or true positive rate. The probability of detection may depend on background noise, the reflectivity of the object, the tolerance of the range, and other attributes. The PoD can be calculated by the following Equation 1, where true (TP) represents scan points that hit the object in its entirety at distance (actual) ±Δ. The probability of detection is calculated as the ratio of the number of valid points to the number of theoretical points.

[0061] [Mathematical Formula 1]

[0062]

[0063] In a point cloud of a LiDAR device according to the present invention, the angle formed by the connection between two adjacent detection points and the 3D coordinate origin of the point cloud in terms of azimuth angle and elevation angle can be referred to as angular resolution. The angular resolution of the LiDAR device can be divided into azimuth resolution and elevation resolution. Angular resolution can be utilized as a performance indicator for the LiDAR device to distinguish one point from another point.

[0064] In a point cloud of a LiDAR device according to the present invention, the angle between two outermost effective points where the PoD exceeds 50% (e.g., Lambertian object reflectance 50%) is called the field of view (FOV) range. The FOV range includes a horizontal FOV range and a vertical FOV range.

[0065] According to the present invention, the frame captures the entire FOV (horizontal / vertical).

[0066] A LiDAR device inspection method according to one embodiment of the present invention is based on ambient light and object reflectance. Ambient light may be an illuminance value measured in kilolux units. Object reflectance may be 10%. Alternatively, ambient light may be radiant illuminance ( It may be an illuminance value measured in units. It may be the sum of the illuminance values ​​of the wavelength band of the device under inspection.

[0067] FIG. 2 is a drawing for explaining the arrangement of a target and an auxiliary light source emitting auxiliary light according to an embodiment of the present invention.

[0068] A target (30) according to one embodiment of the present invention may be connected to an auxiliary light source (40) that emits auxiliary light. The auxiliary light source (40) may be configured to emit auxiliary light having the same illuminance or characteristics as sunlight.

[0069] Additionally, the auxiliary light may be light having the same spectrum (wavelength band) as sunlight. The auxiliary light may output light of a wavelength band corresponding to the light wavelength band sensed by the sensor of the photodetector (12) or a wavelength band of light filtered by the bandpass filter of the photodetector (12). The auxiliary light emitted from the auxiliary light source (40) may be emitted through the opening (41) formed in the target (30).

[0070] Additionally, the auxiliary light source (40) can be configured to be connected to the target (30) and to irradiate auxiliary light through the opening.

[0071] The auxiliary light source (41) may be a light source for creating a specific environment, and examples of the light source for creating a specific environment may be a light source for creating an environment that causes interference to test the robustness of the LiDAR against interference light, or a light source for creating an environment that creates ambient light caused by sunlight in an outdoor environment.

[0072] Additionally, the aperture (41) may be configured to have a size smaller than the angular resolution of the device under inspection. Furthermore, the shape of the aperture (41) may be configured in an optimal form for detecting the effects of various lights. For example, depending on the characteristics of the light (e.g., scattering, frequency, wavelength, intensity, etc.), it may be configured in an appropriate shape (e.g., slit, square, rectangle, polygon, and circle).

[0073] Additionally, the target (30) may include multiple targets. Specifically, some of the multiple targets may be configured to be connected to an auxiliary light source (40), and the remainder of the multiple targets may be configured not to be connected to an auxiliary light source (40). For example, if the target (30) includes two targets, one target (30) may be placed on the front and the rear of the inspection target device (10), respectively, and the front target (30) may be configured to be connected to an auxiliary light source (40), while the rear target (30) may be configured not to be connected to an auxiliary light source (40).

[0074] In addition, the target (30) can be configured in various forms depending on the test environment. According to one embodiment, the target (30) can be configured in a circular or polygonal shape (e.g., a square, a rectangle, a pentagon, etc.). In addition, the target (30) can be composed of a material having various optical properties depending on the test environment. For example, the target (30) can be configured to have at least one of a material having a relatively high reflectance (e.g., 95% or more) and / or a relatively low reflectance (e.g., 5% or less). For example, the target (30) can be configured to include at least one of a material having total reflection properties and / or a material having retroreflection properties.

[0075] In addition, in the LiDAR test method according to the present invention, the target (30) may be arranged or configured so that light emitted from the light emitter (or light transmitter) of the inspection target device (10) is reflected and received by the light detector (or light receiver) of the inspection target device (10), such as the auxiliary light emitted from the auxiliary light source (40).

[0076] In addition, the inspection target device (10) according to one embodiment of the present invention may include a photodetector and a photoemitter. The photodetector may include a photoreceiver, and the photoemitter may include a phototransmitter.

[0077] FIG. 3a is a drawing illustrating that auxiliary light is irradiated onto a photodetector of a device to be inspected according to an embodiment of the present invention. FIG. 3b is a drawing illustrating that auxiliary light is not irradiated onto a photodetector of a device to be inspected according to an embodiment of the present invention.

[0078] Referring to FIG. 3a, light emitted from an auxiliary light source (40) according to one embodiment of the present invention is irradiated to a light receiver of a photodetector of an inspection target device (10) through an aperture (41) connected to a target (30). Specifically, auxiliary light emitted from the auxiliary light source (40) is irradiated to a photodetector of an inspection target device (40) through the aperture (41). In order for the auxiliary light to be irradiated to a photodetector of an inspection target device (10) through the aperture (41), the auxiliary light source (40), the aperture (41), and the photodetector of the inspection target device (10) may be configured to be aligned in a straight line (e.g., in the direction of sight). Additionally, the auxiliary light may be irradiated to cover an area greater than the area of ​​the receiving portion of the photodetector so as to be incident on the entire active area of ​​the sensor of the photodetector. To this end, an optical device (e.g., a lens, etc.) for diffusing the output light may be placed in the auxiliary light source.

[0079] Referring to FIG. 3b, when light emitted from an auxiliary light source (40) according to one embodiment of the present invention travels along a light path extending through an aperture (41) connected to a target (30), it may not be irradiated to a light detector of the inspection target device (10). Specifically, the inspection target device (10) may be configured to be rotatable or movable. Thus, the inspection target device (10) may be rotatable or movable so that the auxiliary light source (40), the aperture (41), and the light detector of the inspection target device (10) described in FIG. 3a are not aligned. As a result, the inspection target device (10) is not aligned along the light path extending through the auxiliary light source (40) and the aperture (41), so that light emitted from the auxiliary light source (40) may not be irradiated to a light detector of the inspection target device (10).

[0080] Figure 4 is a diagram illustrating the radiant intensity of sunlight in an external environment.

[0081] The LiDAR test method according to the present invention can be performed in an external environment or in an internal environment created under conditions similar to the external environment. In this case, in order to create an internal environment under conditions similar to the external environment, the internal environment can be created based on the radiant intensity of sunlight in the external environment.

[0082] The radiant intensity of sunlight can be represented by a wavelength-iron intensity graph, as shown in Fig. 4. Specifically, the radiant intensity of sunlight is based on the blackbody radiation graph of the sun, and the radiant intensity of sunlight can be divided into sunlight at sea level and sunlight in a state where no absorption by the atmosphere occurs, indicated at the outermost edge of the graph. For example, the wavelength-iron intensity graph can be distinguished through the ASTM-G173-03 solar radiant intensity standard using a 5778K blackbody radiation graph.

[0083] The solar radiation illuminance in the external environment described above can be used to create an internal environment for testing external light interference caused by sunlight in the actual environment where the LiDAR device is operated. Specifically, if the illuminance and intensity of external light in the internal environment differ from those in the external environment, at least one of the wavelength, intensity, and illuminance of the auxiliary light emitted from the auxiliary light source can be adjusted according to the solar radiation illuminance by wavelength.

[0084] FIG. 5 is a diagram illustrating an environment for inspecting a LiDAR device according to one embodiment of the present invention.

[0085] Referring to FIG. 5, an inspection target device (10), which is a LiDAR device according to one embodiment of the present invention, may be installed and prepared, and an object (20) may be prepared. Additionally, an external light source (50) may be present or placed in the environment for inspecting the LiDAR device. Furthermore, indoor light may be installed in the indoor measurement environment for measuring the LiDAR device. The shape of the object (20) may be a flat plate or a three-dimensional shape. The indoor light may include a fluorescent lamp, LED lighting, a halogen lamp, a natural light simulator, a laser pointer, UV lighting, or infrared lighting.

[0086] Referring to FIG. 5, an environment for testing a LiDAR device according to one embodiment of the present invention can detect reflected light emitted from a device (10) to be tested and reflected by an object (20) to test performance indicators of the device (10) to be tested, which is a LiDAR device. The performance indicators may include at least one of distance accuracy, distance precision, range performance, resolution, and angular resolution.

[0087] FIG. 6a is a diagram illustrating illuminance measurement using a light measuring instrument in an environment for inspecting a LiDAR device according to one embodiment of the present invention.

[0088] Referring to FIG. 6a, illuminance measurement using a light measuring instrument according to one embodiment of the present invention may be performed by placing a light measuring instrument (60) at the location of the inspection target device (10) of FIG. 2. Specifically, the light measuring instrument (60) may align its measurement direction to match the direction toward which the inspection target device (10) is directed at the location where the inspection target device (10) is placed. Additionally, since the inspection target device (10) may be affected by reflected light from the floor and ceiling, the light measuring instrument (60) may have a field of view (FOV) range that matches the field of view (FOV) range of the inspection target device (10). Furthermore, the field of view (FOV) range of the light measuring instrument (60) may be a range that includes the floor but does not include the ceiling.

[0089] More specifically, according to one embodiment of the present invention, a portion of the field of view (FOV) of the light measuring device (60) may include the ground between the inspection target device (10) and the object (20) within the range, and a portion of the field of view (FOV) may not include the ceiling between the inspection target device (10) and the object (20). Additionally, the light measuring device (60) may be positioned so that a portion of the field of view (FOV) includes the ground within the range and does not include the ceiling within the range.

[0090] In addition, the inspection target device (10) and the light measuring instrument (60) according to one embodiment of the present invention may be arranged such that the centerline of the field of view (FOV) range is deflected toward the ground surface with respect to the horizontal plane. For example, when the elevation angle field of view (FOV) range of the inspection target device (10) and the light measuring instrument (60) is 30 degrees, the centerline of the field of view range may be deflected toward the ground surface with respect to the horizontal plane, and the elevation angle of the field of view range above the horizontal plane may be 5 degrees, and the elevation angle of the field of view range below the horizontal plane may be 25 degrees.

[0091] According to one embodiment of the present invention, the light measuring device (60) is a device for measuring ambient light in an environment for testing a LiDAR device and may include an illuminance meter, a spectrometer, a lumen meter, a lux meter, a radiometer, a photometer, a colorimeter, an infrared meter, and a UV light meter.

[0092] FIG. 6b is a diagram illustrating the arrangement of a LiDAR device and a light measuring instrument in an environment for inspecting a LiDAR device according to an embodiment of the present invention.

[0093] Referring to FIG. 6b, an environment for testing a LiDAR device according to one embodiment of the present invention may include a device to be inspected (10), an object (20), an external light source (50), a first light measuring device (61) positioned to be oriented in the same direction as the direction of the device to be inspected (10), and a second light measuring device (62) positioned to be oriented in the same direction as the direction of the device to be inspected (10).

[0094] The first light measuring device (61) and the second light measuring device (62) may be aligned to have the same orientation as the device to be inspected (10) and may be positioned to have the same height as the device to be inspected (10). Specifically, the device to be inspected (10) may include a light receiver or a light detector, and the first and second light measuring devices (61, 62) may be positioned at the same height as the height at which the light receiver or light detector of the device to be inspected (10) is positioned.

[0095] Additionally, the first light measuring device (61) and the second light measuring device (62) according to one embodiment of the present invention may have different field of view ranges. Specifically, the field of view range of the first light measuring device (61) may be smaller than the field of view range of the inspection target device (10), and the field of view range of the second light measuring device (62) may be larger than the field of view range of the inspection target device (10). As described above, when the field of view range of the first light measuring device (61) is smaller than the field of view range of the inspection target device (10), the distance from the first light measuring device (61) to the object (20) is greater than the distance from the inspection target device (10) to the object (20). Therefore, the size and dimensions of the object (20) included in the field of view range of the inspection target device (10) and the size and dimensions of the object (20) included in the field of view range of the first light measuring device (61) may be similar or identical. Likewise, if the field of view of the second light measuring device (62) is larger than the field of view of the inspection target device (10), the distance from the second light measuring device (62) to the object (20) is shorter than the distance from the inspection target device (10) to the object (20), so the size and dimensions of the object (20) included in the field of view of the inspection target device (10) and the size and dimensions of the object included in the field of view of the second light measuring device (62) may be similar or identical.

[0096] Additionally, each of the first light measuring device (61) and the second light measuring device (62) may be spaced apart from the inspection target device (10) at the same distance, and the first light measuring device (61) and the second light measuring device (62) may be spaced apart from each other at the same distance.

[0097] FIG. 7 is a top view illustrating the arrangement of a LiDAR device and a light measuring instrument according to one embodiment of the present invention.

[0098] Referring to FIG. 7a, the first light measuring instrument (61) and the second light measuring instrument (62) may be positioned on the left and right sides of the inspection target device (10). Additionally, the first light measuring instrument (61) and the second light measuring instrument (62) may be positioned to face the object (20), just as the inspection target device (10) is positioned to face the object (20).

[0099] In addition, the field of view of the first light measuring instrument (61) and the second light measuring instrument (62) positioned on the left and right sides of the inspection target device (10) according to one embodiment of the present invention may be narrower than the field of view of the inspection target device (10).

[0100] Referring to FIG. 7b, the first light measuring device (61) and the second light measuring device (62) may be positioned at the front and rear of the inspection target device (10). The first light measuring device (61) and the second light measuring device (62) may be positioned to face the object (20) as described above.

[0101] FIG. 8a is a top view illustrating the arrangement of a LiDAR device and a light measuring instrument according to one embodiment of the present invention.

[0102] Referring to FIG. 8a, the light measuring device (60) may be configured in multiple units. Specifically, the multiple light measuring devices (60) may each be spaced apart from the inspection target device (10) by the same distance, and each of the multiple light measuring devices (60) may be spaced apart from each other by the same distance. Additionally, each of the multiple light measuring devices (60) may be placed at the same height as the inspection target device (10). Furthermore, the multiple light measuring devices (60) may be placed to face the object (20), just as the inspection target device (10) is placed to face the object (60).

[0103] In addition, when the measurement area and the field of view overlap in the direction toward the object (20) according to one embodiment of the present invention, some of the light measuring instruments whose field of view overlaps among the measurement areas may not be placed or may be removed.

[0104] Additionally, a plurality of optical measuring instruments (46) according to one embodiment of the present invention may be arranged based on the field of view of the inspection target device (10). Specifically, if the field of view of each of the plurality of optical measuring instruments (60) is smaller than the field of view of the inspection target device (10), they may be arranged so as to be biased to include the field of view of the inspection target device (10).

[0105] FIG. 8b is a top view illustrating the arrangement of the LiDAR device and the optical measuring instrument according to FIG. 8a.

[0106] Referring to FIG. 8b, a LiDAR inspection device according to one embodiment of the present invention may include a light measuring device and an inspection target device (10). The light measuring device may include a plurality of light measuring devices. For example, the light measuring device may include a first light measuring device (61), a second light measuring device (62), a third light measuring device (63), and a fourth light measuring device (64). Each of the first to fourth light measuring devices (61, 62, 63, 64) may be spaced apart from the inspection target device (10) by the same distance, and each of the first to fourth light measuring devices (61, 62, 63, 64) may be spaced apart from each other by the same distance.

[0107] A LiDAR device inspection device and method according to one embodiment of the present invention may not place or remove an object when measuring ambient light through a light measuring instrument. By not placing or removing the object, the error in illuminance measurement caused by reflected light reflected from the object can be minimized.

[0108] In a method for inspecting a LiDAR device according to one embodiment of the present invention, when measuring, the measuring person may perform the measurement by positioning themselves below or at a distance from the height of the light measuring device to minimize the influence on the measurement of ambient light of the light measuring device.

[0109] A LiDAR device inspection method according to one embodiment of the present invention can measure ambient light by repeating the measurement multiple times in order to increase the accuracy of the ambient light measurement of the light measuring instrument. Specifically, the illuminance of the ambient light can be measured by repeating the measurement two or more times, and the measured illuminance can be averaged to determine the ambient light illuminance value.

[0110] In addition, a method for inspecting a LiDAR device according to one embodiment of the present invention measures the illuminance of ambient light using a light measuring instrument, and if the illuminance of ambient light is not within a predetermined range (preferably 75 klux to 100 klux), the ambient light of the surrounding environment can be set to a predetermined range to inspect the LiDAR device. An ambient light control unit may be used to adjust the ambient light to a predetermined range.

[0111] In a LiDAR device inspection method according to one embodiment of the present invention, the field of view of the light measuring device may be smaller than the field of view of the device to be inspected (10). Specifically, since the field of view of the light measuring device is smaller than the field of view of the device to be inspected (10), the field of view of the device to be inspected (10) can be covered by using a plurality of light measuring devices.

[0112] In addition, the LiDAR test method according to one embodiment of the present invention may have a field of view of a light measuring instrument that is different from the field of view of the device to be inspected (10). Depending on the characteristics of the reflected light incident on the LiDAR device and the noise characteristics of the LiDAR, a light measuring instrument that is wider or narrower than the field of view of the device to be inspected (10) may be used.

[0113] FIG. 9a is a diagram illustrating that, in a test device, an auxiliary light is irradiated onto a light receiver. FIG. 9b is a diagram illustrating that, in the test device of FIG. 9a, the device to be inspected is rotated so that the auxiliary light is not irradiated onto the light receiver.

[0114] A test device (100) according to an embodiment of the present invention, which is subject to a change in the azimuth angle of a device to be inspected, may include a device to be inspected (110), a movable target (120), and an auxiliary light source (130). As illustrated in FIG. 9a, the device to be inspected (110) according to an embodiment of the present invention may be configured to be spaced apart from the movable target (120) by a distance of s. Additionally, the auxiliary light source (130) according to an embodiment of the present invention may be configured to be movable and connected to the target (120).

[0115] An inspection target device (110) according to one embodiment of the present invention may include an optical receiver (112) and an optical transmitter (114). The inspection target device (110) may further include an optical receiver rotation reference point (116).

[0116] Referring to FIG. 9a, a reference light emitted from a reference light source (130) can be irradiated onto a light receiver (112) of a device to be inspected (110). When the reference light is turned off so that it is not irradiated onto the light receiver (112) of the device to be inspected (110), light under normal conditions without separate interference light can be measured. Additionally, when the reference light is irradiated onto the light receiver (112) of the device to be inspected (110), light under external light interference conditions can be measured by comparing it with the light measured under normal conditions.

[0117] Referring to FIG. 9b, the movable target (120) can be configured to be connected to a reference light source (130) and can move differently from the arrangement in FIG. 9a. As the target (120) moves, the reference light emitted from the reference light source (130) is not irradiated onto the light receiver (112).

[0118] As the target (120) moves, the measurement conditions can be changed from conditions where the reference light is irradiated to conditions where it is not irradiated to conditions where it is not irradiated, or conversely, from conditions where it is not irradiated to conditions where it is irradiated. Accordingly, the effect of interference caused by the reference light and external light can be measured precisely.

[0119] FIG. 10a is a test apparatus of FIG. 9a, wherein the device to be tested is exposed to optical interference according to the azimuth angle. This is a drawing to explain the state rotated at an azimuth angle. FIG. 10b is a test device of FIG. 9b, wherein the device to be inspected measures optical interference according to the azimuth angle. This is a drawing to explain the state rotated by the azimuth angle.

[0120] Referring to FIG. 10a, the inspection target device (110) of FIG. 9a has an azimuth angle with respect to the optical receiver rotation reference point (116). Can rotate by that amount. Azimuth Even when the light receiver (112) rotates by a certain amount, the reference light emitted from the reference light source (130) can be irradiated to the light receiver (112) of the inspection target device (110). At this time, the azimuth angle Optical interference caused by external light due to changes in can be measured.

[0121] Referring to FIG. 10b, the inspection target device (110) of FIG. 9b has an azimuth angle with respect to the optical receiver rotation reference point (116). Can rotate by that amount. Azimuth When the light receiver (112) rotates by a certain amount, the reference light emitted from the reference light source (130) is not irradiated to the light receiver (112) of the inspection target device (110). At this time, the azimuth angle External light interference and light under normal conditions can be measured according to changes in.

[0122] FIG. 11a is a diagram illustrating that, in a test device, an auxiliary light is irradiated onto a light receiver. FIG. 11b is a diagram illustrating that, in the test device of FIG. 11a, the device to be inspected is rotated so that the auxiliary light is not irradiated onto the light receiver.

[0123] A test device (200) according to an embodiment of the present invention, which is subject to an elevation angle change of a device to be inspected, may include a device to be inspected (210), a movable target (220), and a reference light source (230). As illustrated in FIG. 11a, the device to be inspected (210) according to an embodiment of the present invention may be configured to be spaced apart from the movable target (220) by a distance of s. Additionally, the reference light source (230) according to an embodiment of the present invention may be configured to be movable and connected to the target (220). The device to be inspected (210) according to an embodiment of the present invention may include an optical receiver (212) and an optical transmitter (214). The device to be inspected (210) may further include an optical receiver rotation reference point (216).

[0124] Referring to FIG. 11a, a reference light emitted from a reference light source (230) can be irradiated onto a light receiver (212) of a device to be inspected (210). When the reference light is turned off so that it is not irradiated onto the light receiver (212) of the device to be inspected (210), light under normal conditions can be measured. Additionally, when the reference light is irradiated onto the light receiver (212) of the device to be inspected (210), light under external light interference conditions can be measured by comparing it with the light measured under normal conditions.

[0125] Referring to FIG. 11b, the movable target (220) can be configured to be connected to a reference light source (230) and can move differently from the arrangement in FIG. 11a. As the target (220) moves, the reference light emitted from the reference light source (230) is not irradiated onto the light receiver (212).

[0126] As the target (220) moves, the measurement conditions can be changed from conditions where the reference light is irradiated to conditions where it is not irradiated to conditions where it is not irradiated, or conversely, from conditions where it is not irradiated to conditions where it is irradiated. Accordingly, the effect of interference caused by the reference light and external light can be precisely measured.

[0127] FIG. 12a describes the test apparatus of FIG. 11a, wherein the device to be tested is exposed to optical interference according to the elevation angle. This is a drawing to explain the state rotated at an elevation angle. FIG. 12b is a diagram for explaining the state in which the device to be inspected is exposed to optical interference according to the elevation angle in the optical interference measuring device test device of FIG. 11b. This is a drawing to explain the state rotated at an elevation angle.

[0128] Referring to FIG. 12a, the inspection target device (210) of FIG. 11a has an elevation angle with respect to the optical receiver rotation reference point (216). Can rotate by that amount. Elevation angle Even when the light receiver (212) rotates by that amount, the reference light emitted from the reference light source (230) can be irradiated to the light receiver (212) of the inspection target device (210). At this time, the elevation angle Optical interference caused by external light due to changes in can be measured.

[0129] Referring to FIG. 12b, the inspection target device (210) of FIG. 8b has an elevation angle with respect to the optical receiver rotation reference point (216). Can rotate by that amount. Elevation angle When the light receiver (212) rotates by that amount, the reference light emitted from the reference light source (230) is not irradiated to the light receiver (212) of the inspection target device (210). At this time, the elevation angle External light interference and light under normal conditions can be measured according to changes in.

[0130] FIG. 13 is a diagram illustrating the operation of a LiDAR test device according to an embodiment of the present invention. FIG. 14 is a diagram illustrating the operation of optical interference measurement according to an elevation angle of a LiDAR test device according to an embodiment of the present invention. FIG. 15 is a diagram illustrating the operation of optical interference measurement according to an azimuth angle of a LiDAR test device according to an embodiment of the present invention.

[0131] Specifically, FIG. 13 is a diagram illustrating the operation of a LiDAR optical interference measurement device (300) using a movable target. The LiDAR optical interference measurement device (300) using a movable target may include a device to be inspected (310), a movable target (320), and a reference light source (330) that emits reference light.

[0132] Here, the movable target (320) can move in the up, down, left, and right directions and can have a size sufficient to reflect light emitted from the light transmitter of the inspection target device (310).

[0133] Referring again to FIG. 13, FIG. 13(a) is a diagram illustrating the state in which a reference light source (330) emitting reference light and a light receiver of a device to be inspected (310) are aligned. As shown in FIG. 13(a), when the light receiver of the device to be inspected (310) and the reference light source (330) are aligned and the reference light of the reference light source (330) is in the on state, the device to be inspected (310) can measure light under external light interference conditions.

[0134] Next, referring to FIG. 13(b), the movable target (320) can be moved diagonally upward from the arrangement of FIG. 13(a). In this case, the light receiver of the inspection target device (310) and the reference light source (330) are not aligned, and regardless of whether the reference light of the reference light source (330) is on / off, the inspection target device (310) can measure light under conditions without external light interference.

[0135] By comparing the light measurement values ​​in states (a) and (b) of Fig. 13, the degree and effect of light interference in external light interference can be measured.

[0136] Specifically, FIG. 14 is a diagram for explaining the operation of a LiDAR optical interferometer (400) using a movable target in a state where the inspection target device of FIG. 13 is rotated in the azimuth direction. The LiDAR optical interferometer (400) using a movable target may include an inspection target device (410) in a state where it is rotated in the azimuth direction, a movable target (420), and a reference light source (430) that emits reference light.

[0137] Here, the movable target (420) can move in the up, down, left, and right directions and can have a size sufficient to reflect light emitted from the light transmitter of the inspection target device (410).

[0138] Referring again to FIG. 14, FIG. 14(a) is a diagram illustrating the state in which a reference light source (430) emitting reference light and a light receiver of a device to be inspected (410) are aligned. As shown in FIG. 14(a), when the light receiver of the device to be inspected (410) and the reference light source (430) are aligned and the reference light of the reference light source (430) is in the on state, the device to be inspected (410) can measure light under external light interference conditions.

[0139] Next, referring to FIG. 14(b), the movable target (420) can be moved diagonally upward from the arrangement of FIG. 12(a). In this case, the light receiver of the inspection target device (410) and the reference light source (430) are not aligned, and regardless of whether the reference light of the reference light source (430) is on / off, the inspection target device (410) can measure light under conditions without external light interference.

[0140] By comparing the light measurement values ​​in states (a) and (b) of Fig. 14, the degree and effect of light interference in external light interference according to the rotation angle in the azimuth direction of the device under inspection can be measured.

[0141] Specifically, FIG. 15 is a diagram for explaining the operation of a LiDAR optical interferometer (500) using a movable target in a state where the inspection target device of FIG. 13 is rotated in the elevation angle direction. The LiDAR optical interferometer (500) using a movable target may include an inspection target device (510) in a state where it is rotated in the elevation angle direction, a movable target (520), and a reference light source (530) that emits reference light.

[0142] Here, the movable target (520) can move in the up, down, left, and right directions and can have a size sufficient to reflect light emitted from the light transmitter of the inspection target device (510).

[0143] Referring again to FIG. 15, FIG. 15(a) is a diagram illustrating the state in which a reference light source (530) emitting reference light and a light receiver of a device to be inspected (510) are aligned. As in FIG. 13(a), when the light receiver of the device to be inspected (510) and the reference light source (530) are aligned and the reference light of the reference light source (530) is in the on state, the device to be inspected (510) can measure light under external light interference conditions.

[0144] Next, referring to FIG. 15(b), the movable target (520) can be moved diagonally upward from the arrangement of FIG. 15(a). In this case, the light receiver of the inspection target device (510) and the reference light source (530) are not aligned, and regardless of whether the reference light of the reference light source (530) is on / off, the inspection target device (510) can measure light under conditions without external light interference.

[0145] By comparing the light measurement values ​​in states (a) and (b) of Fig. 15, the degree and effect of light interference in external light interference according to the rotation angle in the elevation angle direction of the device under inspection can be measured.

[0146] FIG. 16 is a flowchart illustrating a LiDAR test method according to one embodiment of the present invention.

[0147] Referring to FIG. 16, a LiDAR test method according to one embodiment of the present invention may include the steps of preparing a device to be tested (S110), placing a light measuring instrument in the direction of the device to be tested (S120), measuring light in the test environment with the light measuring instrument and performing a performance test of the device to be tested (S130), and recording at least one of the measured light in the test environment, the performance of the device to be tested, and the influence of light in the test environment (S140).

[0148] In the step of preparing the device to be tested (S110), the device to be tested, including the light emitter and photodetector described with reference to FIGS. 1 to 15, can be placed in a test environment. Specifically, it can be placed according to the performance or effect to be tested of the device to be tested. In addition, the light emitter and photodetector can be placed separately depending on the purpose of the test.

[0149] Additionally, in the step of preparing the device to be inspected (S110), an auxiliary light source may be placed to configure the test environment so that external light is present. Specifically, the auxiliary light source emits auxiliary light, and the auxiliary light may be irradiated to the light receiver of the photodetector of the device to be inspected.

[0150] The output of the auxiliary light emitted from the auxiliary light source can be adjusted to create a test environment similar to the operating environment of an actual LiDAR device in the presence of ambient light. Specifically, the output of the auxiliary light can be adjusted based on the radiant intensity of sunlight (e.g., refer to the graph in Fig. 4). In this case, when adjusting the output of the auxiliary light, the auxiliary light can be adjusted according to the wavelength band of the auxiliary light. For example, when adjusting the wavelength bands of 750 nm and 1000 nm, the 750 nm is 0.5 W / m² 2 Increase, and 1000nm is 0.5W / m² 2 It can be adjusted, such as by reducing.

[0151] The step (S120) of positioning a light measuring instrument in the direction of the device to be inspected may be performed such that the light measuring instrument is positioned in the direction of the receiver of the device to be inspected in order to similarly measure the light from the outside received by the light receiver of the device to be inspected. In this case, the light measuring instrument can measure light of a wavelength corresponding to the bandpass filter of the light receiver of the device to be inspected. Additionally, the light measuring instrument may be W / m 2 Radiant illuminance expressed in units can be measured.

[0152] The step (S130) of measuring light in a test environment with a light measuring instrument and performing a performance test of the device to be inspected measures light in the established test environment and performs a performance test of the device to be inspected. Performance that can be measured through the test of the device to be inspected may include angular resolution, distance performance, occurrence of ghosting, occurrence of blooming, etc.

[0153] In addition, the step (S130) of performing a performance test on the device under inspection can measure how the performance of the device under inspection changes according to interference caused by external light by adjusting the intensity of the auxiliary light. Specifically, the auxiliary light is irradiated onto the optical receiver of the device under inspection, and the extent to which the interference phenomenon caused by the auxiliary light impairs the performance of the device under inspection can be measured.

[0154] Subsequently, the test result value can be recorded in the step (S140) of recording at least one of the measured light of the test environment, the performance of the device under inspection, and the influence of the light of the test environment. Then, the steps (S110-140) can be repeated to evaluate the performance by averaging the obtained values.

[0155] Although the detailed description of the invention above has been given with reference to preferred embodiments of the invention, those skilled in the art should understand that various modifications and changes can be made to the invention without departing from the spirit and scope of the invention as described in the claimed patent claims.

Claims

1. Regarding LiDAR test methods, Step of preparing the device to be inspected; A step of positioning a light measuring instrument in the orientation of the above-mentioned inspection target device; A step of measuring light in a test environment with the above-mentioned light measuring instrument and performing a performance test of the above-mentioned device to be inspected; and A method comprising the step of recording at least one of the light of the test environment, the performance of the device under inspection, and the influence of the light of the test environment. LiDAR testing method.

2. In Paragraph 1, A step further comprising placing an auxiliary light source, LiDAR testing method.

3. In Paragraph 2, The auxiliary light emitted by the above auxiliary light source has a wavelength band corresponding to the optical wavelength band of the optical receiver and optical transmitter of the device to be inspected, LiDAR testing method.

4. In Paragraph 2, The step of placing the above auxiliary light source is, A step comprising controlling auxiliary light emitted from the above auxiliary light source, LiDAR testing method.

5. In Paragraph 4, The above auxiliary light is adjusted based on the radiant intensity of sunlight, LiDAR testing method.

6. In Paragraph 4, The above auxiliary light has its intensity adjusted according to wavelength band, LiDAR testing method.

7. In Paragraph 1, The above light measuring instrument measures light of a wavelength corresponding to the wavelength band of the bandpass filter of the light receiver of the device under inspection. LiDAR testing method.

8. In Paragraph 1, The above light measuring instrument is W / m 2 Measuring radiant illuminance expressed as, LiDAR testing method.

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