A light splitting device, a light receiving device, a sensing apparatus, and a terminal apparatus
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- YINWANG INTELLIGENT TECHNOLOGIES CO LTD
- Filing Date
- 2025-05-19
- Publication Date
- 2026-06-26
Smart Images
Figure CN224417120U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of detection technology, and in particular to a beam splitting device, a light receiving device, a sensing device, and a terminal device. Background Technology
[0002] A beam splitter can separate an incident light beam into multiple beams, making it an indispensable optical component in scenarios such as multi-path detection, data fusion, and optical signal feedback monitoring, thereby improving the integration of equipment. For example, using a beam splitter in a detection device to split the beam into two separate images before fusion can significantly improve detection accuracy. Compared to using multiple lenses for separate imaging, this simplifies the overall structure and reduces the cost of the detection device.
[0003] However, beam splitters also have structural limitations. The beams separated by beam splitters often contain a lot of interference signals, which can easily lead to an increase in the signal-to-noise ratio of the back-end sensors and affect the detection accuracy of the sensors. Utility Model Content
[0004] This application provides a beam splitter, a light receiving device, a sensing device, and a terminal device, which can improve the signal-to-noise ratio of the output beam without significantly increasing the size of the beam splitter, and help reduce the petal ghosting problem of the sensor.
[0005] In a first aspect, this application provides a beam splitting device, including a beam splitting prism and a first filter layer. The beam splitting prism includes a first surface, a second surface, and a third surface. The first filter layer is attached to the second surface to filter the light beam emitted through the second surface. Further, the beam splitting prism is used to split the light beam incident from the first surface into a first beam and a second beam, the first beam emitting from the second surface and the second beam emitting from the third surface.
[0006] In the above embodiments, the filter layer has a filtering function, selectively allowing light beams within a specific wavelength range to pass through while blocking other irrelevant wavelengths. This reduces interference from non-target light and improves the signal-to-noise ratio of the beam emitted after passing through the beam splitter. Especially in the field of detection technology, filtering out unwanted colored light can reduce dispersion problems caused by multicolor light. Moreover, allowing only specific wavelengths of light to pass through can prevent detector saturation or energy waste.
[0007] The first filter layer is attached to the second surface. On the one hand, this allows the filter layer to be fixed using a beam splitter prism, eliminating the need for additional design of the support position and connection structure for the filter components. This simplifies the optical system structure and improves the integration of the device, helping to reduce detection costs. On the other hand, this arrangement effectively shortens the distance between the light-emitting surface of the prism and the first filter layer, thereby effectively shortening the back focal length of the optical system and reducing the design complexity of the optical system.
[0008] In some cases, the beam split by the beam splitter is then fed to the sensor for reception. Attaching the filter layer directly to the light-emitting surface of the prism increases the distance between the prism's light-emitting surface and the sensor, reducing the petal ghosting problem. Petal ghosting occurs when light reflects multiple times between the lenses, ultimately forming a petal-shaped false image (ghost image) on the imaging plane. Attaching the filter layer to the surface of the beam splitter increases the distance between the filter layer and the sensor, allowing stray light to deviate from the sensor area due to its long-distance propagation and increasing the energy attenuation of stray light, thus reducing petal ghosting, improving the sensor's signal-to-noise ratio, and increasing detection accuracy.
[0009] In one possible implementation of the first aspect, the beam splitter is formed by bonding a first right-angle prism and a second right-angle prism together, having a square cross-section, with the inclined surfaces of the two right-angle prisms touching. The first right-angle facet of the first right-angle prism is a first surface, the other right-angle facet is a second surface, and one right-angle facet of the second right-angle prism is a third surface.
[0010] In another possible embodiment of the first aspect, the beam splitter further includes a second filter layer. The second filter layer is attached to the third surface to filter the light beam emitted through the third surface. In the above embodiment, both light-emitting surfaces of the beam splitter are provided with filter layers attached to the light-emitting surfaces, which can filter the two light beams separately, further improving the integration of the device and the signal-to-noise ratio of the emitted signal.
[0011] In another possible implementation of the first aspect, the beam splitter separates light based on wavelength. In other words, the beam splitter is a wavelength beam splitter. The first beam includes beams within a first wavelength range, and the first filter layer is used to filter out beams that do not belong to the first wavelength range.
[0012] Furthermore, the beam splitter also includes a second filter layer, the second beam includes a beam of a second wavelength range, the first wavelength range and the second wavelength range do not overlap at least partially, and the second filter layer is used to filter out beams that do not belong to the second wavelength range.
[0013] In the aforementioned scheme, the beam splitter splits light based on wavelength. On this basis, by using two filter layers with different light transmission properties, unwanted colored light can be filtered out in both output light paths, thereby improving the signal-to-noise ratio of the beam emitted after passing through the beam splitter.
[0014] In another possible implementation of the first aspect, the first filter layer is a filter, which is bonded to the second surface.
[0015] Optionally, the bonding method includes adhesive bonding, glueless direct bonding (relying on intermolecular forces), hot-press bonding, etc. Among them, hot-press bonding refers to using thermoplastic optical adhesive film, heating it to the glass transition temperature and then applying pressure to bond it.
[0016] In another possible implementation of the first aspect, the second filter layer is a filter sheet, and the second filter layer is bonded to the third surface.
[0017] In another possible implementation of the first aspect, the first filter layer is a filter film, which is deposited on the second surface. This design can reduce costs and simplify process complexity. Optionally, the deposition method includes electroplating, coating, deposition, screen printing, etc.
[0018] In another possible implementation of the first aspect, the second filter layer is a filter film, which is deposited on the third surface. This reduces costs and simplifies the process complexity.
[0019] In another possible implementation of the first aspect, the first filter layer contacts a first region of the second surface. The contact area between the first filter layer and the second surface is smaller than the surface area of the second surface. The above embodiments can reduce the aperture of the filter layer and lower the cost of setting the filter layer.
[0020] In another possible implementation of the first aspect, the contact surface between the first filter layer and the second surface covers the beam cross-section when the first light beam passes through the second surface. This improves the filtering effect and prevents stray light from being generated when the light beam illuminates the edge region of the filter layer.
[0021] In another possible implementation of the first aspect, a light-blocking layer is provided on the area of the second surface that is not in contact with the first filter layer. The light-blocking layer, also known as a light-absorbing material layer, is capable of absorbing stray light and improving the signal-to-noise ratio of the beam after passing through the beam splitter.
[0022] In another possible implementation of the first aspect, the second filter layer contacts a second region of the third surface. The contact area between the second filter layer and the third surface is smaller than the surface area of the third surface.
[0023] Optionally, the contact surface between the second filter layer and the third surface covers the beam cross-section when the second beam passes through the third surface.
[0024] Optionally, a light-blocking layer is provided in the area of the third surface that is not in contact with the second filter layer.
[0025] In another possible implementation of the first aspect, the light-blocking layer is disposed on the second surface by one of the following methods: coating, electroplating, screen printing, or adhesive bonding.
[0026] Secondly, this application provides a light receiving device, including an optical module and a first detector. The optical module includes a beam splitter as described in the first aspect or any possible embodiment of the first aspect. The first detector is used to receive a first light beam emitted from a second surface of the beam splitter. The first light beam is filtered by a first filter layer of the beam splitter.
[0027] In the above embodiment, a beam splitter is provided in the light receiving device. The light beam entering the beam splitter is split by a beam splitting prism and then filtered by a filter layer attached to the beam splitting prism. This improves the signal-to-noise ratio of the light beam received by the first detector and also facilitates the miniaturization and integration of the light receiving device. The filter layer can also filter out unwanted colored light, reducing dispersion problems caused by multicolor light. In addition, the beam splitter increases the distance between the light emitting surface of the beam splitter (i.e., the outermost surface of the filter layer) and the sensor, reducing the ghosting effect and improving the accuracy and reliability of the light receiving device.
[0028] Optionally, the first detector is a lidar sensor, comprising multiple photodetectors, such as a p-type intrinsic-n-type photodiode (PIN photodiode), an avalanche photodiode (APD), a single-photon avalanche diode (SPAD), a silicon photomultiplier (SiPM), a multi-pixel photon counter (MPPC), or an electron multiplying charge-coupled device (EMCCD). Furthermore, the data output by the first detector can support time-of-flight calculations to obtain the target's distance, etc. It can also obtain one or more pieces of information, such as the target's velocity, position, reflectivity, texture, or type.
[0029] In some cases, optical receiving devices are installed in sensing devices to achieve high-precision radar imaging. The aforementioned optical receiving devices can significantly improve the signal-to-noise ratio of the received beam, and the size of the adapted lidar is trending towards miniaturization and integration.
[0030] Optionally, the first detector is an image sensor, including a photosensitive element such as a complementary metal oxide semiconductor (CMOS), a charge-coupled device (CCD), or a Live MOS. Further, the data output by the first detector can be used to obtain pixelated brightness and / or color information; for example, the data output by the first detector includes images and / or videos, or the data output by the first detector is used to obtain images and / or videos.
[0031] In some cases, light receiving devices are installed in sensing devices to achieve high-precision image imaging. The aforementioned light receiving devices can significantly improve the signal-to-noise ratio of the received light beam, improve the clarity of the image, and adapt to the miniaturization and integration of the camera size.
[0032] In another possible implementation of the second aspect, the light receiving device further includes a second detector for receiving a second beam emitted from the beam splitter.
[0033] In the above embodiment, the light beams received by the first and second detectors are obtained by splitting the beams using a beam splitter, enabling two detections of the field of view at once. Moreover, the fields of view corresponding to the split beams are at least partially overlapping, which reduces the computational complexity of data fusion and improves the accuracy of the data output by the optical receiving device.
[0034] Optionally, the second detector is an image sensor. Alternatively, the second detector is a lidar sensor. Please refer to the foregoing for a description of the sensor.
[0035] In another possible implementation of the second aspect, the optical module further includes a receiving lens for receiving a light beam from the object space and providing it to the beam splitter.
[0036] In the above embodiment, after the light receiving device receives the light beam through the lens, it further splits the beam by a beam splitter and provides the two beams to the two detectors respectively. No additional optical elements are required between the beam splitter and the detectors. Thus, the light beams received by the first and second detectors share a common viewpoint, which further reduces registration complexity, improves the accuracy of fusion detection, and enhances detection performance.
[0037] In another possible implementation of the second aspect, the receiving lens includes one or more of the following lenses: a meniscus lens, a biconvex lens, a biconcave lens, a plano-concave lens, a plano-convex lens, a plano-concave lens, a plano-convex lens, or a cylindrical lens. The above lens design facilitates a reasonable allocation of shape and optical power, achieving high-quality detection performance.
[0038] In another possible implementation of the second aspect, both the first and second detectors are lidar detectors. The data output by the first detector is a point cloud or can be processed to obtain a point cloud, and the data output by the second detector is a point cloud or can be processed to obtain a point cloud. In this way, the density of the point cloud output by the optical receiving device can be significantly improved, and the detection accuracy can be increased accordingly.
[0039] In another possible implementation of the second aspect, the first detector is a lidar detector, and the second detector is an image detector. The data output by the first detector is a point cloud or can be processed to obtain a point cloud, and the data output by the second detector is an image or can be processed to obtain an image. In this way, the point cloud and image output by the optical receiving device can be accurately registered, and the detection accuracy is correspondingly increased.
[0040] Alternatively, the first detector can be an image detector, and the second detector can be a lidar detector.
[0041] In another possible implementation of the second aspect, both the first detector and the second detector are image detectors. The data output by the first detector is a first image or can be obtained by processing it, and the data output by the second detector is a second image or can be obtained by processing it. The first image and the second image use different wavelengths during imaging; for example, the first image is an infrared image, and the second image is a visible light image. This design allows the light receiving device to operate in all weather conditions, and the first and second images can also be fused to improve image clarity.
[0042] In another possible implementation of the second aspect, the first beam coincides with the optical axis of the incident beam splitter, and the second beam forms an angle with the optical axis of the incident beam splitter, the angle being ≥0°.
[0043] Furthermore, the first detector is a lidar sensor, and the second detector is an image sensor. Since the defocusing amount of the beam splitter's turning optical path is significantly affected by the beam splitter's misalignment, an image sensor with a larger depth of field (DOF) can be placed on the turning optical path of the beam splitter. Conversely, the defocusing amount of the beam splitter's direct optical path is less affected by the beam splitter's misalignment, so a lidar sensor with a smaller DOF can be placed on the direct optical path of the beam splitter. This allows for high-quality imaging of both the first and second detectors.
[0044] In another possible implementation of the second aspect, the beam splitter is based on wavelength. The first detector is an infrared light sensor, and the second detector is a visible light sensor. Alternatively, the first detector is a visible light sensor, and the second detector is an infrared light sensor.
[0045] Thirdly, this application provides a sensing device, which includes a beam splitter as described in any of the first aspects, or a light receiving device as described in any of the second aspects. Further, the sensing device includes a housing, within which the beam splitter or light receiving device is housed.
[0046] Optionally, the sensing device includes sensors that utilize light to sense the environment, such as one or more of LiDAR, cameras, or fusion sensing devices. Fusion sensing devices include various types of sensors such as LiDAR, cameras, and radar.
[0047] Fourthly, embodiments of this application provide a terminal device, which includes a beam splitter according to any of the first aspects, or a light receiving device according to any of the second aspects, or a lidar according to the third aspect.
[0048] Here, "terminal equipment" refers broadly to electronic devices. For example, terminal equipment encompasses one or more electronic devices such as mobile platforms or smart devices. Mobile platforms refer to autonomous or semi-autonomous moving vehicles or equipment, such as vehicles, drones, aircraft, and robots. Smart devices refer to devices that integrate sensors, and also include vehicles, roadside equipment, drones, mobile phones, and robots.
[0049] Alternatively, the terminal device may be a vehicle, drone, or robot.
[0050] For the beneficial effects of the second to fourth aspects of this application, please refer to the beneficial effects of the first aspect. Attached Figure Description
[0051] The accompanying drawings used in the description of the embodiments will be briefly introduced below.
[0052] Figure 1 It is an optical path diagram of the light beam received by a sensor;
[0053] Figure 2 This is a schematic diagram of the structure of a spectrophotometer provided in an embodiment of this application;
[0054] Figure 3 yes Figure 2 The cross-sectional view of the beam-splitting device shown in the ZOX plane;
[0055] Figure 4 This is a schematic diagram of the optical path of a receiving device provided in an embodiment of this application;
[0056] Figure 5 This is a schematic diagram of the structure of another beam-splitting device provided in the embodiments of this application;
[0057] Figure 6 yes Figure 5The cross-sectional view of the beam-splitting device shown in the ZOX plane;
[0058] Figure 7 This is a schematic diagram of the structure of another beam-splitting device provided in the embodiments of this application;
[0059] Figure 8 yes Figure 7 The cross-sectional view of the beam-splitting device shown in the ZOX plane;
[0060] Figure 9 This is a schematic diagram of the structure of an optical receiving device provided in an embodiment of this application;
[0061] Figure 10 This is a schematic diagram of the structure of a lidar provided in an embodiment of this application;
[0062] Figure 11 This is a schematic diagram of the structure of a vehicle including a lidar, provided in an embodiment of this application. Detailed Implementation
[0063] The following section will introduce some of the technical terms.
[0064] A photodetector is a device that converts light signals into electrical signals using the photoelectric effect. Exemplary photodetectors include types such as PIN photodiodes, APDs, SPADs, or SiPMs, and are widely used in fields such as LiDAR (Light Detection and Ranging). To achieve spatially resolved detection, some detectors include multiple photodetectors arranged in an array structure, with one or more photodetectors corresponding to a single pixel. This array design allows the detector to output data in pixel form, enabling individual acquisition and processing of light intensity, timestamps, or photon count information for each pixel, thus generating high-resolution detection results.
[0065] Petal ghosting refers to stray light phenomena caused by reflections from the surfaces of optical elements in an optical system. After light enters the optical system, some rays may reflect multiple times between lenses, ultimately forming a false image (i.e., a petal-shaped ghost) on the imaging plane. Because optical elements are typically circular and the reflection paths are usually symmetrical, ghosts often appear radially or ring-shaped, resembling petals. Once formed, ghosts can easily obscure the real imaging beam, causing blurred imaging details. Furthermore, in the field of detection technology, sensors may misinterpret ghosts as real targets.
[0066] The above description of the terminology can be applied to the examples described below.
[0067] When a beam splitter separates a light beam, irrelevant rays often remain in the resulting beam. To increase the signal-to-noise ratio (SNR) of the split beam, some devices incorporate additional filters to filter the beam, aiming to improve the SNR. See also Figure 1 , Figure 1 This is an optical path diagram for a sensor to receive a light beam. A beam splitter separates the light beam, and the separated beam is then filtered by a filter placed separately from the beam splitter before being received by the sensor.
[0068] but, Figure 1 In the illustrated scheme, the surface design of the filter and the beam splitter prism is separate, requiring the installation of separate support points for the beam splitter prism and the dispensing method within the equipment. Furthermore, due to this surface separation design, the distance between the sensor and the filter is short, making it easy for stray light reflected from the filter surface to enter the sensor, causing severe ghosting issues and resulting in decreased sensor accuracy.
[0069] In view of this, this application provides a beam splitter, a light receiver, a lidar, and a terminal, which can improve the signal-to-noise ratio of the output beam without significantly increasing the size of the beam splitter, and can also reduce the petal ghosting problem of the sensor.
[0070] Please see Figure 2 and Figure 3 , Figure 2 This is a schematic diagram of the structure of a beam splitter provided in an embodiment of this application. Figure 3 yes Figure 2 The diagram shows a cross-sectional view of the beam-splitting device in the ZOX plane. The beam-splitting device 10 includes a beam-splitting prism 11 and a first filter layer 12.
[0071] The beam splitter 11 includes a first surface 113, a second surface 114, and a third surface 115. In some cases, the first surface 113, the second surface 114, and the third surface 115 are all peripheral surfaces of the prism. Furthermore, the beam splitter 11 also includes two bottom surfaces, to which the aforementioned first surface 113, the second surface 114, and the third surface 115 are all connected.
[0072] In this design, the first surface 113 serves as the incident surface, while the second surface 114 and the third surface 115 both allow the light beam to pass through. The beam-splitting prism 11 has a beam-splitting function, capable of splitting the light beam incident through the first surface 113 into a first beam and a second beam. The first beam exits from the second surface 114, and the second beam exits from the third surface 115. In some cases, the beam-splitting prism includes a beam-splitting surface with a beam-splitting film, which performs the beam-splitting function. Exemplarily, the beam-splitting film includes one or more of the following: a multilayer dielectric film, a metal-dielectric composite film, and a metal beam-splitting film. Optionally, the beam-splitting film is deposited on the surface of the beam-splitting surface using a coating technology (such as electron beam evaporation, magnetron sputtering, or electroplating).
[0073] The filter layer, such as the first filter layer 12 and the subsequent second filter layer 13, has a filtering function, selectively allowing light beams within a specific wavelength range to pass through while blocking other irrelevant wavelengths, thereby reducing interference from non-target light. For example, the filter layer can be a bandpass filter, which allows light within a specific wavelength range to pass through, such as an infrared bandpass filter or a visible light bandpass filter. As another example, the filter layer can be a filter film, which may include single-layer or multi-layer filter materials, such as dielectric filter films or metal films.
[0074] In this embodiment, the first filter layer 12 is attached to the second surface 114 to filter the light beam emitted through the second surface 114. For example, after the first light beam is emitted from the second surface 114, the first filter layer 12 filters it, and the filtered first light beam is emitted from the first filter layer 12.
[0075] Since the first filter layer 12 is attached to the second surface, the device using the beam splitter 10 does not require additional design of the support position and connection structure for the filter components, simplifying the optical system structure and improving the integration of the device. On the other hand, since the light beam is transmitted to the sensor after passing through the beam splitter prism and the filter layer, attaching the filter to the outer layer of the beam splitter can shorten the distance between the filter and the sensor, effectively shortening the back focal length of the optical system and reducing the design difficulty of the optical system.
[0076] Consider a kind of Figure 1 In the light receiving device shown, along the direction perpendicular to the receiving target surface of the sensor, the filter and the receiving target surface of the sensor need to be spaced apart (spacing d1), and the filter and the beam splitter also need to be spaced apart (spacing d2). These two intervals compress the distance between the filter and the receiving target surface of the sensor, making it easier for stray light to enter the photosensitive area of the detector, causing a severe petal ghosting problem. Figure 1 The following explanation will be based on stray light with an angle θ to the principal optical axis.
[0077] Please see Figure 4 , Figure 4 This is a schematic diagram of the optical path of a receiving device provided in an embodiment of this application. The first filter layer 12 is attached to the surface of the beam splitter 11, which effectively lengthens the distance between the first filter layer 12 and the receiving target surface of the detector 20 (as a sensor). For example, the distance can be lengthened to d3, where d3 > d1. Stray light with an angle θ with the principal optical axis is more likely to deviate from the photosensitive area of the detector 20 after traveling through a longer propagation distance, and its energy will attenuate with the increase of propagation distance. This can greatly reduce the possibility of stray light entering the photosensitive area of the detector 20, reduce the petal ghosting problem, improve the signal-to-noise ratio of the sensor, and increase the detection accuracy.
[0078] In the above description, the first beam is reflected by the beam-splitting surface of the beam-splitting prism, and the first beam forms an angle with the incident beam. This design is merely an example. In some cases, the optical paths of the first beam and the second beam can be interchanged. In other words, the first beam may be a beam that is transmitted through the beam-splitting surface of the beam-splitting prism, in which case the first filter layer 12 is also correspondingly disposed on the optical path of the first beam.
[0079] In some possible implementations, combined Figure 2 and Figure 3 The beam-splitter 11 comprises two prisms, referred to for ease of description as a first prism 111 (a square near the z-axis) and a second prism 112 (near the negative z-axis). For example, it is formed by gluing the first prism 111 and the second prism 112 together; gluing can be replaced by other fixing methods. Further, at least one of the glued surfaces is coated with a beam-splitting film. Optionally, the gluing method includes adhesive bonding, glue-free direct bonding (relying on intermolecular forces), hot-press bonding, etc., wherein hot-press bonding refers to using a thermoplastic optical adhesive film, heating it to its glass transition temperature, and then applying pressure to bond them together. For example, the first prism 111 and the second prism 112 are bonded together with optical adhesive.
[0080] For example, both the first prism 111 and the second prism 112 are right-angle prisms, and the inclined surfaces of the two right-angle prisms are in contact, with the contact surface being the beam-splitting surface. The cross-section of the beam-splitting prism 11 along the ZOX axis is square. Figure 3 The surface on which the first right-angled side of the first prism 111 is located is the first surface 113, the surface on which the other right-angled side is located is the second surface 114, and the surface on which one right-angled side of the second prism 112 is located is the third surface 115.
[0081] The above implementation of a square beam splitter formed by cementing right-angle prisms is merely an example. In some cases, beam splitters may have other structures, such as a wedge-shaped structure. Figure 5 and Figure 6 , Figure 5 This is a schematic diagram of the structure of another beam-splitting device provided in the embodiments of this application. Figure 6 yes Figure 5The diagram shows a cross-sectional view of the beam-splitting device in the ZOX plane. The beam-splitting prism 11 can be formed by bonding two non-right-angled prisms together, and the cross-section of the beam-splitting prism 11 along the ZOX plane is polygonal. The first prism 111 includes a first surface 113, a second surface 114, a fourth surface 116, and a fifth surface, while the second prism 112 includes a third surface 115, a seventh surface 117, and an eighth surface. The fifth surface of the first prism 111 and the eighth surface of the second prism are bonded together, for example, by an adhesive layer. An incident light beam enters the first prism 111 from the first surface 113 and is split by the fifth surface (or the eighth surface) to obtain a first beam and a second beam. The first beam is incident on the fourth surface 116, which reflects it again, causing the first beam to exit from the second surface 114. The second beam is incident on the seventh surface 117 and reflected by it, causing the second beam to exit from the third surface 115.
[0082] Optionally, more prisms can be added to the beam splitter 10 to form more sub-beams. For example, the second beam can be split by another beam splitter prism. In this case, the beam can be divided into three sub-beams.
[0083] In some possible implementations, the beam splitter 11 splits light based on wavelength. For example, the first beam includes a beam within a first wavelength range, and the second beam includes a beam within a second wavelength range, wherein the first and second wavelength ranges do not overlap at least partially. For instance, the first wavelength range includes the wavelength range containing infrared light, and the second wavelength range includes the wavelength range containing visible light; in other words, the beam splitter can separate visible light and infrared light, with the first beam and the second beam being infrared light and visible light, or visible light and infrared light, respectively.
[0084] In some designs, the beam-splitting prism includes a beam-splitting surface. This surface has different reflectivity and transmittance properties for different wavelengths of light, enabling the separation of beams across different wavelengths and thus achieving the beam-splitting function. Table 1 below describes a common color of light and its corresponding wavelength range.
[0085]
[0086]
[0087] It should be noted that the wavelength ranges shown in Table 1 are only examples of possible wavelength ranges. The upper and lower limits of each wavelength range can also refer to one or more of the following standard documents or recommended schemes from organizations: standard documents for ophthalmic optics and ophthalmic devices, standard documents for ISO 20473:2007 optics and photonics - spectral bands, the International Commission on Illumination classification system, or astronomical classification schemes.
[0088] For example, the beam-splitting surface of a beam-splitting prism has low reflectivity in a wavelength range less than 750 nm (e.g., a first wavelength range). In other words, most light signals with wavelengths less than 750 nm are transmitted when passing through the beam-splitting surface of this prism. In a wavelength range greater than 800 nm (e.g., a second wavelength range), the reflectivity is high. In other words, most light signals with wavelengths greater than 800 nm are reflected when passing through the beam-splitting surface of this prism. Referring to Table 1 above, the beam-splitting surface of the prism can reflect infrared light and transmit visible light, thereby achieving the effect of separating light in different wavelength ranges.
[0089] Of course, those skilled in the art should know that due to the physical limitations and manufacturing processes of optical devices, the beam separation achieved by a beam splitter is not absolute. On the one hand, wavelength splitting may involve certain transition regions and cross-effects. For example, in the wavelength range of 750nm to 800nm, the reflectivity and transmittance of the beam splitter surface will exhibit gradual changes, and some optical signals may be reflected and transmitted simultaneously. On the other hand, a small amount of stray light will still exist in each beam after wavelength-based splitting. For instance, visible light with wavelengths less than 750nm, although most (greater than 50%) is transmitted when passing through the beam splitter surface, a very small portion (less than 50%) will still be reflected due to surface scattering or film defects. Similarly, infrared light with wavelengths greater than 800nm may also have a small amount of transmission rather than complete reflection.
[0090] In some possible implementations, the first filter layer 12 is used to filter out light beams that do not belong to the first wavelength range. For example, a beam splitter splits light based on wavelength, where the first wavelength range is the wavelength range of visible light. For instance, if the first light beam is visible light, the first filter layer 12 can filter out non-visible light beams. Alternatively, if the first wavelength range is below 750 nm, the first filter layer 12 is used to filter out colored light not falling within the range below 750 nm. In some cases, the first filter layer 12 can filter out light beams not belonging to the first wavelength range, and also filter out light within a wider range. In other words, the wavelength range of light allowed to pass through the first filter layer 12 can be set to be smaller. For example, the first filter layer 12 can only allow light beams in the wavelength range of 380 nm to 750 nm to pass through, and can filter out light with wavelengths below 380 nm and above 750 nm.
[0091] In some possible implementations, the beam-splitting prism 11 can also be based on other criteria for beam splitting. For example, the beam-splitting prism 11 can be a polarizing beam-splitting prism, thus allowing beam splitting based on polarization state. Alternatively, the beam-splitting prism 11 can be a transmission-reflection mirror, with beam splitting based on energy; for example, the beam-splitting prism 11 might transmit 50% of the beam and reflect 50%, i.e., a half-transmission, half-reflection beam-splitting mirror. Of course, the beam splitting energy here is merely an example; for instance, the beam-splitting prism could also be a beam-splitting mirror with 40% transmission and 60% reflection.
[0092] In some possible implementations, the beam splitter 10 further includes a second filter layer 13. The second filter layer 13 is attached to the third surface 115 of the beam splitter prism 11 to filter the light beam emitted through the third surface 115. In other words, filter layers are attached to both light-emitting surfaces of the beam splitter prism 11, enabling separate filtering of the two light beams, which can further improve the integration of the device and the signal-to-noise ratio of the emitted signal. In some cases, the attachment method, area constraints, and other characteristics of the second filter layer can be referred to the description of the first filter layer herein. Optionally, the attachment method, area constraints, and other characteristics of the second filter layer 13 may be the same as, different from, or partially the same as the first filter layer 12.
[0093] Optionally, when the beam splitter 11 splits light based on wavelength, the second beam includes a beam within a second wavelength range, and the first wavelength range and the second wavelength range do not overlap at least partially. The second filter layer 13 is used to filter out beams that do not belong to the second wavelength range. For example, if the first beam is infrared light, the second filter layer 13 can filter out non-infrared light. As another example, if the first wavelength range is above 800 nm, the second filter layer 13 is used to filter out colored light that does not belong to the range above 800 nm. In some cases, the second filter layer 13 can filter out a wider range of light; in other words, the light transmission range of the second filter layer 13 can be set to be smaller. For example, the second filter layer can only transmit beams in the wavelength range of 800 nm to 1000 μm, and can filter out light with wavelengths below 800 nm and above 1000 μm.
[0094] Optionally, the surfaces described above are all peripheral surfaces. In some cases, the beam splitter 11 also includes a top surface and a bottom surface, and the top surface and / or the bottom surface may be provided with a light-blocking coating (such as a light-absorbing coating) to reduce stray light. In some embodiments, since the optical path is reversible, the beam splitter 11 may also have a beam-combining function.
[0095] The structure and function of the beam splitter have been introduced above. Below, we will introduce two possible implementations of the filter layer:
[0096] Achieve 1The first filter layer 12 is a filter, which is bonded to the second surface 114. In other words, the first filter layer 12 can form a structural component on its own, which can be bonded and fixed to the surface of the beam splitter 11 by adhesive bonding. Optionally, the bonding method includes adhesive bonding, adhesive-free direct bonding (relying on intermolecular forces), hot-press bonding, etc., wherein hot-press bonding refers to using a thermoplastic optical film, heating it to the glass transition temperature and then applying pressure to bond it.
[0097] Optionally, if the beam splitter 10 further includes a second filter layer 13, the second filter layer 13 is a filter, and the second filter layer 13 is bonded to the third surface 115. The bonding method is described above.
[0098] Achieve 2 The first filter layer 12 is a filter film, which is deposited on the second surface 114. Optionally, the coating can be applied by one or more processes such as electroplating, coating, screen printing or deposition.
[0099] Optionally, if the spectrophotometer 10 further includes a second filter layer 13, the second filter layer 13 is a filter film, and the second filter layer 13 is deposited on the third surface 115. Optionally, the deposition method can use one or more processes such as electroplating, coating, or deposition.
[0100] In some cases, the filter layer does not need to completely cover one outer peripheral surface of the beam splitter in order to reduce the area of the filter layer and thus reduce costs.
[0101] As one possible implementation method, please refer to Figure 7 and Figure 8 The first filter layer 12 contacts a first region of the second surface 114. The contact area between the first filter layer 12 and the second surface 114 is smaller than the surface area of the second surface 114. In other words, a portion of the second surface 114 exposes the first filter layer 12 and is not covered by it. This design reduces the filter layer aperture and lowers the cost of setting the filter layer.
[0102] Furthermore, the contact surface between the first filter layer 12 and the second surface 114 covers the beam cross-section when the first beam passes through the second surface 114. That is, after the first beam exits through the second surface 114, the beam enters the first filter layer 12, and the beam spot does not illuminate the area not covered by the first filter layer 12. This design can ensure the filtering effect.
[0103] In some possible implementations, a light-blocking layer 14 is provided on the area of the second surface 114 that is not in contact with the first filter layer 12. The light-blocking layer 14 is used to block light beams, for example, by absorbing light beams, thereby generating stray light on the surface. Optionally, the material of the light-blocking layer 14 may include a light-absorbing oil film. Optionally, the light-blocking layer is disposed on the second surface by one of the following methods: coating, electroplating, screen printing, or adhesive bonding.
[0104] In one possible implementation, the second filter layer 13 contacts a second region of the third surface 115. The contact area between the second filter layer 13 and the third surface 115 is smaller than the surface area of the third surface.
[0105] Optionally, the contact surface between the second filter layer 13 and the third surface 115 covers the beam cross-section when the second beam passes through the third surface 115.
[0106] Optionally, a light-blocking layer 14 is provided in the area of the third surface 115 that does not contact the second filter layer 13.
[0107] The following describes an optical receiving device provided in an embodiment of this application. Please refer to... Figure 9 , Figure 9 This is a schematic diagram of the structure of an optical receiving device provided in an embodiment of this application. The optical receiving device 100 includes an optical module and a first detector 20. The optical module includes the aforementioned beam splitter 10, such as... Figures 2 to 7 The spectral splitter 10 described in the illustrated embodiment and its possible implementations.
[0108] The beam splitter 10 can split the incident light to obtain a first beam and a second beam, and the first detector 20 is used to receive the first beam. Specifically, the beam received by the first detector 20 is emitted from the second surface 114 of the beam splitter prism 11 and filtered by the first filter layer 12 in the beam splitter 10. Due to the beam splitting by the first filter layer 12, the signal-to-noise ratio of the beam received by the first detector is improved, and the dispersion problem caused by multicolor light is reduced. At the same time, it is also beneficial to the miniaturization and integration of the light receiving device. Moreover, the first filter layer 12 is attached to the surface of the beam splitter prism 11. This design can lengthen the distance between the light emitting surface of the beam splitter (i.e., the outermost surface of the first filter layer 12) and the first detector 20, reduce the ghosting problem, and improve the accuracy and reliability of the light receiving device. Related descriptions can also be found in... Figure 4 The illustrated embodiments are described below.
[0109] Optionally, the first detector 20 includes multiple photodetectors, such as PIN photodiodes, APDs, SPADs, SiPMs, MPPCs, EMCCDs, etc. Furthermore, the data output by the first detector 20 can be used for time-of-flight calculations to obtain the target's distance, etc. It can also obtain one or more pieces of information such as the target's speed, position, reflectivity, texture, or type.
[0110] In some cases, the light receiving device 100 is included in a sensing device, such as a lidar, or a sensing device that incorporates lidar. A lidar is a sensor that uses active detection technology to detect object space. For example, the lidar transmitter can emit a laser beam, and the lidar receiver, such as the light receiving device 100, can receive the echo. The information from the echo can reflect information about the target in the object space.
[0111] Optionally, the first detector 20 includes a photosensitive element, such as a CMOS, CCD, or Live MOS. Further, the data output by the first detector 20 can be used to obtain pixelated brightness and / or color information; for example, the data output by the first detector 20 may include images and / or videos, or the data output by the first detector 20 may be used to obtain images and / or videos.
[0112] In some possible implementations, the light receiving device 100 further includes a second detector 30 for receiving a second beam emitted from the beam splitter 10. For example, the beam received by the first detector 20 is emitted from the third surface 115 of the beam splitter prism 11. Further, the beam splitter 10 also includes a second filter layer 13 attached to the third surface 115 of the beam splitter prism 11, through which the second beam is filtered. Thus, the beam splitter 10 can split an incident beam into two paths, enabling the light receiving device 100 to simultaneously detect and fuse the two paths, significantly improving the detection accuracy in the object space. Moreover, the fields of view corresponding to the split beams are at least partially overlapping, reducing the computational complexity of data fusion and improving the data reliability of the light receiving device.
[0113] Optionally, the second detector 30 includes multiple photodetectors. Alternatively, the second detector 30 includes multiple photosensitive elements. See the description of the first detector 20 above for a related description.
[0114] In some schemes, the first detector 20 and the second detector 30 are of the same type, for example, both are SPAD arrays or both are CMOS image sensors.
[0115] In some other designs, the first detector 20 and the second detector 30 are of different types. For example, the first detector 20 is a SPAD array, and the second detector 30 is a CMOS image sensor. Or, the first detector 20 is an APD array, and the second detector 30 is a single-channel image sensor. The optical receiving device 100 uses multiple types of sensors for fusion detection, combining the advantages of various sensors and significantly improving detection accuracy.
[0116] In some possible implementations, the first detector 20 is used to respond to a light beam within a first wavelength range, or the operating band of the first detector covers the light beam within the first wavelength range. The second detector 30 is used to respond to a light beam within a second wavelength range, or the operating band of the second detector covers the second wavelength range. For example, the first detector 20 may be an infrared light sensor, and the second detector 30 may be a visible light sensor, or vice versa. As another example, the first detector 20 may be used to receive echoes, and the light beam emitted by the transmitting end of the device containing the first detector 20 may be infrared light, while the second detector 30 may be a visible light image sensor, or vice versa.
[0117] In some possible implementations, the optical module further includes a receiving lens 40. In some cases, the receiving lens 40 includes one or more lenses. For example, the receiving lens 40 includes one or more lenses such as a meniscus lens, a biconvex lens, a biconcave lens, a plano-concave lens, a plano-convex lens, a plano-concave lens, a plano-convex lens, a cylindrical lens, etc.
[0118] In some possible implementations, the receiving lens 40 is used to receive the beam from the object space and provide it to the beam splitter 10. This architecture places the receiving lens close to the object side and the beam splitter 10 close to the image side, i.e., "beam splitter rear-mounted". This allows the two beams split by the beam splitter 10 to have the same viewpoint. The matching degree between the data output by the first detector 20 and the data output by the second detector 30 is higher, which can improve the accuracy of fusion detection and improve detection performance.
[0119] To make it easier to understand, three possible scenarios are described below:
[0120] In scenario 1, the data output by the first detector 20 is a point cloud or can be obtained after processing, and the data output by the second detector 30 is also a point cloud or can be obtained after processing. In this way, the density of the point cloud output by the optical receiving device can be significantly improved, and the detection accuracy can be increased accordingly.
[0121] In scenario 2, the first detector 20 outputs a point cloud or, after processing, a point cloud; the second detector 30 outputs an image or, after processing, an image. In this way, the point cloud and image output by the optical receiving device can be accurately registered, thus increasing the detection accuracy.
[0122] Scenario 3: The data output by the first detector 20 is a first image, or can be obtained by processing it to form a first image; the data output by the second detector 30 is a second image, or can be obtained by processing it to form a second image. The first image and the second image use different wavelengths during imaging; for example, the first image is an infrared image, and the second image is a visible light image. This design allows the light receiving device to image the object space in all weather conditions, and the first and second images can also be fused to improve image clarity.
[0123] Of course, the above three scenarios are merely examples. In actual implementation, the outputs of the first detector 20 and the second detector 30 may have many more possibilities. For example, the data output by the first detector 20 may include point clouds or images, or the output data may be processed to simultaneously produce point clouds and images. Regardless of the form of the data output by the first detector 20 and the second detector 30, splitting it into two paths by the same beam splitter 10 can improve the detection efficiency and accuracy of the light receiving device in the object space.
[0124] This application provides a sensing device, which includes the described beam splitter 10 or the aforementioned light receiving device 100. Further, the sensing device includes a housing, within which the beam splitter 10 or the light receiving device 100 is housed.
[0125] Optionally, the sensing device includes sensors that utilize light to sense the environment, such as one or more of LiDAR, cameras, or fusion sensing devices. Fusion sensing devices include various types of sensors such as LiDAR, cameras, and radar.
[0126] Please see Figure 10 , Figure 10 This is a schematic diagram of the structure of a sensing device provided in an embodiment of this application. The sensing device 200 includes a light receiving device 100 and a light emitting device 300.
[0127] The light emitting device 300 is capable of generating an emitted light beam. For example, the light emitting device 300 includes a light source. Exemplarily, the light source includes one or more of a vertical surface-emitting laser (VCSEL) and / or an edge-emitting laser (EEL). When the VCSEL is mounted on a circuit board, its emitting surface is parallel to the surface of the circuit board, such as one or more of VCSELs, photonic crystal surface-emitting semiconductor lasers (PCSELs), horizontal cavity surface-emitting lasers (HCSELs), and fiber lasers. For example, the first light source can be a single VCSEL chip or a VCSEL chip array formed by splicing multiple VCSEL chips. An edge-emitting laser refers to a laser that emits light through a side surface; in other words, when the edge-emitting laser is mounted on a circuit board, its emitting surface is a side surface (or a surface perpendicular to the circuit board). Alternatively, the EEL can be replaced with other devices that emit light at the edge of the light-emitting element, such as silicon photonic chips.
[0128] The light receiving device 100 is used to receive the returned light beam, which includes the echo of the emitted light beam and may also include light from other light sources in the environment. The light emitting device is able to obtain relevant information about targets in the environment based on the echo of the emitted light beam.
[0129] Furthermore, the light receiving device 100 is also used to receive a light beam from the object space, the light beam from the object space including a return beam and also including background light, and the light receiving device 100 is able to obtain at least a point cloud of the environment using the return beam, and obtain an image of the environment using the background beam.
[0130] This application embodiment also provides a terminal, which includes the aforementioned light splitting device 10, or the aforementioned light receiving device 100, or the sensing device 200. The terminal device here can be a vehicle, drone, mobile phone, roadside equipment, or robot, or other intelligent terminal or means of transportation. It should be understood that "vehicle" here is a broad concept, and can be a means of transportation (such as commercial vehicles, passenger cars, motorcycles, flying cars, trains, etc.), industrial vehicles (such as forklifts, trailers, tractors, etc.), engineering vehicles (such as excavators, bulldozers, cranes, etc.), agricultural equipment (such as lawnmowers, harvesters, etc.), etc. Furthermore, the robot can be an automated guided vehicle (AGV), a walking conversational robot, a service robot, etc.
[0131] Please see Figure 11 , Figure 11This is a schematic diagram of a vehicle structure including a sensing device, provided in an embodiment of this application. The sensing device can sense the vehicle's surrounding environment and obtain relevant information about targets in the surrounding environment. This target-related information can be used to control the vehicle or assist the driver in driving. It should be understood that... Figure 11 The installation location of the sensing device shown is for illustrative purposes only. In actual implementations, the sensing device can be installed in other locations, such as the top of the cockpit, or even at the front, side, or rear of the vehicle.
[0132] In addition, a few additional points need to be made regarding this application:
[0133] I. The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to depart from the protection scope of the technical solutions of the embodiments of this application.
[0134] 2. Unless otherwise stated, “multiple” means two or more.
[0135] 3. Unless otherwise specified or in case of logical conflict, the terms and / or descriptions in different embodiments of this application are consistent and can be referenced by each other. Technical features in different embodiments can be combined to form new embodiments based on their inherent logical relationships.
[0136] IV. The various numerical designations used in this application are merely for descriptive convenience and are not intended to limit the scope of protection of this application. The magnitude of the serial numbers used in this application does not imply a sequential order of execution; the execution order of each process should be determined by its function and internal logic. For example, the terms "first," "second," "third," "fourth," and other various terminology (if present) in the specification, claims, and drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. Such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein.
[0137] Furthermore, any embodiment or design described in this application as "exemplary" or "for example" should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner for ease of understanding.
[0138] V. The terms “comprising” and “having” and any variations thereof are intended to cover a non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or modules is not necessarily limited to those steps or modules that are expressly listed, but may include other steps or modules that are not expressly listed or that are inherent to such process, method, product or device.
[0139] VI. The terms “center,” “upper,” “lower,” “left,” “right,” “vertical,” “horizontal,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.
[0140] VII. The Cartesian coordinate system and the x, y, z directions shown in the various embodiments of this application are exemplary identifiers for ease of understanding and are not intended to limit the embodiments of this application. In actual implementation, the placement of devices, the arrangement direction, and the direction of the beam may be designed differently, and other coordinate systems such as spherical coordinates may also be used.
[0141] 8. Unless otherwise stated, " / " indicates that the objects before and after are in an "or" relationship. For example, A / B can mean A or B. In this application, "and / or" is merely a description of the relationship between the related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. A and B can be singular or plural.
[0142] 9. Unless otherwise stated, the names of devices, systems, modules and other information in the embodiments of this application are merely examples, and devices, modules and modules are used to represent possible entities that implement a certain function, and the meanings of the three can be used interchangeably.
[0143] 10. For ease of explanation, the dimensions and shapes of components (such as beam splitters, filter layers, etc.) in the accompanying drawings of the embodiments of this application are slightly exaggerated. Specifically, the dimensions and surface shapes of the components shown in the drawings are illustrated by way of example. Furthermore, the drawings are for illustrative purposes only and are not strictly drawn to scale.
Claims
1. A spectrophotometer, characterized in that, The beam-splitting device includes a beam-splitting prism and a first filter layer. The beam-splitting prism includes a first surface, a second surface, and a third surface. The beam splitter is used to split the light beam incident from the first surface into a first beam and a second beam, the first beam exiting from the second surface and the second beam exiting from the third surface. The first filter layer is attached to the second surface to filter the light beam emitted through the second surface.
2. The spectrophotometer according to claim 1, characterized in that, The beam splitter is formed by bonding two right-angle prisms together along their mating surfaces.
3. The spectrophotometer according to claim 2, characterized in that, The beam-splitting prism splits light based on wavelength; The first light beam includes light beams within a first wavelength range, and the first filter layer is used to filter out light beams that do not belong to the first wavelength range.
4. The spectrophotometer according to claim 1 or 2, characterized in that, The beam splitter further includes a second filter layer, which is attached to the third surface to filter the light beam emitted through the third surface.
5. The spectrophotometer according to any one of claims 1-4, characterized in that, The beam-splitting prism splits light based on wavelength; The second beam includes a beam in a second wavelength range, wherein the first wavelength range and the second wavelength range do not overlap at least partially; The second filter layer is used to filter out light beams that do not belong to the second wavelength range.
6. The spectrophotometer according to any one of claims 1-5, characterized in that, The first filter layer is a filter, and the filter is bonded to the second surface.
7. The spectrophotometer according to any one of claims 1-6, characterized in that, The first filter layer is a filter film, which is deposited on the second surface.
8. The spectrophotometer according to any one of claims 1-7, characterized in that, The first filter layer is in contact with a first region of the second surface; The contact area between the first filter layer and the second surface is smaller than the surface area of the second surface.
9. The spectrophotometer according to claim 8, characterized in that, The contact surface between the first filter layer and the second surface covers the beam cross-section when the first light beam passes through the second surface.
10. The spectrophotometer according to any one of claims 1-9, characterized in that, A light-blocking layer is provided in the area of the second surface that does not contact the first filter layer.
11. The spectrophotometer according to any one of claims 1-10, characterized in that, The light-blocking layer is fixed to the second surface by one or more processes such as coating, electroplating, screen printing or bonding.
12. An optical receiving device, characterized in that, The optical receiving device includes an optical module and a first detector; The optical module includes the beam-splitting device according to any one of claims 1-11. The first detector is used to receive the first beam emitted from the beam splitter.
13. The optical receiving device according to claim 12, characterized in that, The optical module also includes a receiving lens. The receiving lens is used to receive the light beam from the object space and provide it to the beam splitter.
14. The optical receiving device according to claim 12 or 13, characterized in that, The optical receiving device also includes a second detector. The second detector is used to receive the second beam emitted from the beam splitter.
15. The optical receiving device according to claim 14, characterized in that, The first detector is a lidar detector, and the second detector is an image detector, or the first detector is an image detector, and the second detector is a lidar detector; Alternatively, both the first detector and the second detector may be lidar detectors; Alternatively, both the first detector and the second detector may be image detectors.
16. The optical receiving device according to claim 14, characterized in that, The beam splitter is based on wavelength; in: The first detector is an infrared light sensor, and the second detector is a visible light sensor; Alternatively, the first detector may be a visible light sensor and the second detector may be an infrared light sensor.
17. The optical receiving device according to any one of claims 12-16, characterized in that, The first beam coincides with the optical axis of the beam incident on the beam splitter. The second beam forms an angle with the optical axis incident on the beam splitter, and the angle is ≥0°.
18. The optical receiving device according to claim 17, characterized in that, The receiving lens includes one or more of the following: a meniscus lens, a biconvex lens, a biconcave lens, a plano-concave lens, a plano-convex lens, a plano-concave lens, a plano-convex lens, or a cylindrical lens.
19. A sensing device, characterized in that, The sensing device includes a light emitting device, which is used to emit a laser beam into the object space; in: The sensing device further includes a beam splitter as described in any one of claims 1-11, wherein the light beam from the object space passes through the beam splitter, and the light beam from the object space includes the echo of the laser beam; or... The sensing device further includes a light receiving device according to any one of claims 12-18, the light receiving device being used to receive the return beam of the laser beam.
20. A terminal device, characterized in that, The terminal device includes a beam splitter as described in any one of claims 1-19. Alternatively, it may include the optical receiving device as described in any one of claims 12-18; Alternatively, it may include the sensing device as described in claim 19.
21. The terminal device according to claim 20, characterized in that, The terminal device can be a vehicle, drone, or robot.