Monomer projector and manufacturing method thereof, depth camera and mobile robot

Abstract

The invention provides a single projector and a manufacturing method thereof, a depth camera and a mobile robot, which can solve the problem that an existing single sensor cannot realize mapping navigation and obstacle avoidance functions at the same time, simplify the structure and reduce the cost. The single projector comprises a circuit substrate, a first light-emitting light source, a second light-emitting light source, a micro-lens array and a diffusion element. The second light-emitting light sources and the first light-emitting light sources are arranged on the same surface of the circuit substrate at intervals. The diffusion element is arranged on the light-emitting side of the first light-emitting light source and the light-emitting side of the second light-emitting light source, and the microlens array is located in a light path between the first light-emitting light source and the diffusion element; the diffusion element is used for expanding the light beams collimated by the microlens array in the horizontal direction to form a first output light field and expanding the light beams emitted by the second light emitting source in the horizontal direction and the vertical direction to form a second output light field with the vertical divergence angle larger than that of the first output light field.

Description

Technical Field

[0001] The present invention relates to the field of depth detection technology, and in particular to a single projector and a manufacturing method thereof, a depth camera and a mobile robot. Background Art

[0002] With the rapid development of mobile robot technology, sweeping robots, service robots and industrial robots have been widely used in life and production. During operation, mobile robots must rely on various sensors to perceive the external environment and then execute various instructions based on environmental information. Obstacle avoidance and positioning and mapping are two of the more critical functions of mobile robots. At present, mobile robots usually need to use lidar sensors with a large detection distance to achieve positioning and mapping functions, while line structured light or TOF sensors with a large detection range are required to achieve obstacle avoidance. This means that existing mobile robots need to use a combination of multiple sensors to achieve both mapping navigation and obstacle avoidance functions, such as a solution that uses a combination of line structured light / TOF sensors and lidar sensors. However, the structural design of this solution is relatively complex and the cost is inevitably high, which is not conducive to promotion and popularization. Summary of the invention

[0003] One advantage of the present invention is that it provides a single projector and a manufacturing method thereof, a depth camera and a mobile robot, which can solve the problem that the existing single sensor cannot simultaneously realize mapping navigation and obstacle avoidance functions, simplify the structure and reduce the cost.

[0004] Another advantage of the present invention is that it provides a single projector and a manufacturing method thereof, a depth camera and a mobile robot. In one embodiment of the present invention, the depth camera can use a single projector to project a strong light field and a weak light field respectively to obtain navigation depth information and obstacle avoidance depth information correspondingly, thereby realizing navigation and obstacle avoidance functions at the same time.

[0005] Another advantage of the present invention is that it provides a single projector and a manufacturing method thereof, a depth camera and a mobile robot. In one embodiment of the present invention, the depth camera can project strong light fields and weak light fields in time-sharing to perform mapping navigation and obstacle avoidance in time-sharing, which helps to reduce the impact of mutual multipath interference between strong light fields and weak light fields, improve measurement accuracy, and facilitate improved mapping and obstacle avoidance effects.

[0006] Another advantage of the present invention is that it provides a single projector and a manufacturing method thereof, a depth camera and a mobile robot. In one embodiment of the present invention, the single projector can use a microlens array to collimate the light beam emitted by the first light source, which helps to reduce the size of the projector and reduce costs.

[0007] Another advantage of the present invention is that it provides a single projector and a manufacturing method thereof, a depth camera and a mobile robot. In one embodiment of the present invention, the depth camera is capable of concentrating the light spot through a strong light field with a smaller divergence angle, so as to achieve higher light intensity while reducing multipath interference of the strong light spot.

[0008] Another advantage of the present invention is that it provides a single projector and a manufacturing method thereof, a depth camera and a mobile robot. In one embodiment of the present invention, the depth camera can diverge the light spot through a weak light field with a larger divergence angle, which is beneficial to reduce the obstacle avoidance blind spot and prevent the mobile robot from colliding due to the inability to recognize close objects, thereby affecting the user experience.

[0009] Another advantage of the present invention is that it provides a single projector and a manufacturing method thereof, a depth camera and a mobile robot. In one embodiment of the present invention, the mobile robot can achieve mapping navigation and obstacle avoidance functions through only one depth camera, which reduces the design and assembly difficulty of the whole machine, greatly reduces the cost, and facilitates promotion and popularization.

[0010] Another advantage of the present invention is to provide a single projector and a method for manufacturing the same, a depth camera and a mobile robot, wherein in order to achieve the above-mentioned purpose, no complex system is required in the present invention. Therefore, the present invention successfully and effectively provides a solution, not only providing a simple single projector and a method for manufacturing the same, a depth camera and a mobile robot, but also increasing the practicality and reliability of the single projector and a method for manufacturing the same, a depth camera and a mobile robot.

[0011] In order to achieve at least one of the above advantages or other advantages and purposes of the present invention, the present invention provides a single projector, comprising:

[0012] Circuit board;

[0013] A first light source, the first light source being electrically disposed on the circuit substrate;

[0014] a second light source, the second light source being electrically disposed on the circuit substrate, and the second light source and the first light source being arranged at intervals on the same surface of the circuit substrate;

[0015] a microlens array, the microlens array being arranged on the light emitting side of the first light emitting source and being used for collimating the light beam emitted by the first light emitting source; and

[0016] A diffusion element, wherein the diffusion element is arranged on the light-emitting side of the first light source and the second light source, and the microlens array is located in the light path between the first light source and the diffusion element; the diffusion element is used to expand the light beam collimated by the microlens array in the horizontal direction to form a first output light field, and to expand the light beam emitted by the second light source in the horizontal and vertical directions to form a second output light field with a vertical divergence angle greater than the first output light field.

[0017] According to an embodiment of the present application, both the first light source and the second light source are vertical cavity surface emitting lasers; and the diffusion element is a diffusion sheet or a light homogenizer.

[0018] According to one embodiment of the present application, the diffusion element has a first functional area corresponding to the first light source and a second functional area corresponding to the second light source, and the optical microstructure surface of the first functional area is different from the optical microstructure surface of the second functional area.

[0019] According to an embodiment of the present application, a vertical divergence angle of the first output light field is less than 20°, and a vertical divergence angle of the second output light field is greater than or equal to 40° and less than or equal to 100°.

[0020] According to an embodiment of the present application, horizontal divergence angles of the first output light field and the second output light field are both greater than 100°.

[0021] According to one embodiment of the present application, the luminous power of the first light source is greater than the luminous power of the second light source.

[0022] According to one embodiment of the present application, the microlens array includes a light-transmitting substrate and a plurality of microlens units arrayed on the light-transmitting substrate; each point light source on the first light source is located at the back focus of the corresponding microlens unit.

[0023] According to an embodiment of the present application, the light-transmitting substrate of the microlens array is mounted on the light-emitting surface of the first light source.

[0024] According to one embodiment of the present application, the single projector further includes a bracket disposed on the circuit substrate, and the diffusion element and the microlens array are correspondingly assembled on the bracket.

[0025] According to one embodiment of the present application, the bracket includes a base mounted on the circuit substrate and a step group extending inward from the base, the diffusion element is fixed to the base, and the microlens array is fixed to the step group.

[0026] According to one embodiment of the present application, the step group includes a first step and a second step, the first step and the second step are arranged at intervals along a direction perpendicular to the arrangement direction of the first light source and the second light source, and the opposite sides of the light-transmitting substrate are correspondingly attached to the first step and the second step respectively.

[0027] According to an embodiment of the present application, projections of the remaining two sides of the light-transmitting substrate on the first light source are located within the edge range of the first light source.

[0028] According to one embodiment of the present application, the step group further includes a third step away from the second light source and / or a fourth step away from the first light source, and the remaining edge of the light-transmitting substrate is correspondingly attached to the third step and / or the fourth step.

[0029] According to another aspect of the present application, the present application further provides a depth camera, including:

[0030] Any of the above-mentioned single-body projectors; and

[0031] A receiver is correspondingly arranged on the side of the single projector.

[0032] According to another aspect of the present application, the present application further provides a mobile robot, comprising:

[0033] The robot body; and

[0034] The above-mentioned depth camera is installed on the robot body, and is used to provide navigation depth information and obstacle avoidance depth information for the robot body.

[0035] According to another aspect of the present application, the present application further provides a method for manufacturing a single projector, comprising the steps of:

[0036] Mounting the microlens array and the diffusion element on the bracket respectively;

[0037] Pre-positioning the bracket and the circuit substrate mounted with the first light source and the second light source by dispensing glue, so that the microlens array is located in the light path between the first light source and the diffusion element;

[0038] Adjusting the bracket relative to the first light source so that each point light source on the first light source is located at the back focus of the corresponding microlens unit on the microlens array; and

[0039] The glue is cured to fix the bracket to the circuit substrate to complete the assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic structural diagram of a mobile robot according to an embodiment of the present application;

[0041] Figure 2 A stereoscopic schematic diagram of a depth camera in a mobile robot according to the above embodiment of the present application is shown;

[0042] Figure 3 A first example of a depth camera according to the above embodiment of the present application is shown;

[0043] Figure 4 A schematic cross-sectional view of a depth camera at a first light source according to the first example of the present application is shown;

[0044] Figure 5 A schematic cross-sectional view of a depth camera at a second light source according to the first example of the present application is shown;

[0045] Figure 6 A partial enlarged schematic diagram of a single projector in a depth camera according to the first example of the present application is shown;

[0046] Figure 7 A second example of a single projector in a depth camera according to the above embodiment of the present application is shown;

[0047] Figure 8 A third example of a single projector in a depth camera according to the above embodiment of the present application is shown;

[0048] Fig. 9 A fourth example of a single projector in a depth camera according to the above embodiment of the present application is shown;

[0049] Fig.10 It is a flowchart of a method for acquiring depth information according to an embodiment of the present application.

[0050] Explanation of the main component symbols: 1. Depth camera; 10. Single projector; 11. Circuit substrate; 12. First light source; 120. Point light source; 13. Second light source; 14. Microlens array; 141. Transparent substrate; 142. Microlens unit; 15. Diffusion element; 151. First functional area; 152. Second functional area; 16. Bracket; 161. Base; 162. Step group; 1621. First step; 1622. Second step; 1623. Third step; 1624. Fourth step; 20. Receiver; 21. Circuit board; 22. Photosensitive component; 23. Receiving lens; 24. Heightening block; 2. Robot body.

[0051] The above description of the main component symbols is combined with the accompanying drawings and specific implementation methods to further illustrate the present invention in detail. DETAILED DESCRIPTION

[0052] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art can think of other obvious variations. The basic principles of the present invention defined in the following description can be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not deviate from the spirit and scope of the present invention.

[0053] Those skilled in the art should understand that, in the disclosure of the present invention, the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0054] In the present invention, the term "one" in the claims and the specification should be understood as "one or more", that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple. Unless it is clearly indicated in the disclosure of the present invention that the number of the element is only one, the term "one" cannot be understood as unique or single, and the term "one" cannot be understood as a limitation on the quantity.

[0055] In the description of the present invention, it should be understood that "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through a medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0057] Considering that existing mobile robots need to use a combination of multiple sensors to achieve both mapping navigation and obstacle avoidance functions, the structural design is relatively complex and the cost is inevitably high, which is not conducive to promotion and popularization. The present application provides a single projector and its manufacturing method, a depth camera and a mobile robot, which can solve the problem that the existing single sensor cannot achieve both mapping navigation and obstacle avoidance functions, simplify the structure and reduce the cost.

[0058] Specifically, refer to the accompanying drawings of the specification of this application. Figures 1 to 9 According to an embodiment of the present application, a mobile robot is provided, which may include a depth camera 1 and a robot body 2. The depth camera 1 is mounted on the robot body 2, and the depth camera 1 is used to provide the robot body 2 with long-range depth information and short-range depth information, thereby realizing a mapping navigation function and an obstacle avoidance function. It is understandable that although the robot body 2 of the mobile robot of the present application is taken as an example of a sweeping robot in the accompanying drawings, it is not limited thereto, and can also be implemented as other robots that require navigation and obstacle avoidance.

[0059] More specifically, if Figures 2 to 6As shown, the depth camera 1 may include a single projector 10 and a receiver 20 correspondingly arranged on the side of the single projector 10. The single projector 10 may include a circuit substrate 11, a first light source 12 electrically arranged on the circuit substrate 11, a second light source 13 electrically arranged on the circuit substrate 11, a microlens array 14 and a diffusion element 15; the first light source 12 and the second light source 13 are arranged at intervals on the same surface of the circuit substrate 11; the microlens array 14 is arranged on the light emitting side of the first light source 12, and is used to collimate the light beam emitted by the first light source 12. The diffusion element 15 is arranged on the light-emitting side of the first light source 12 and the second light source 13, and the microlens array 14 is located in the light path between the first light source 12 and the diffusion element 15; the diffusion element 15 is used to expand the light beam collimated by the microlens array 14 in the horizontal direction to form a first output light field, and to expand the light beam emitted by the second light source 13 in the horizontal and vertical directions to form a second output light field with a vertical divergence angle greater than the first output light field. It can be understood that the horizontal direction mentioned in this application refers to the direction corresponding to the horizontal field angle of the depth camera 1, such as Figure 4 The vertical direction mentioned in this application refers to the direction corresponding to the vertical field of view of the depth camera 1, such as Figure 3 The up and down directions in .

[0060] It is worth noting that, since the single projector 10 is provided with a microlens array 14 on the light-emitting side of the first light source 12, the first output light field projected by it has a small divergence angle in the vertical direction, so that the light beam of the first output light field is relatively concentrated for long-distance detection, so the receiver 20 can obtain long-distance depth information when receiving the echo light field corresponding to the first output light field, so as to realize functions such as mapping, positioning and navigation; at the same time, since the single projector 10 is not provided with a microlens array 14 on the light-emitting side of the second light source 13, the second output light field projected by it has a large divergence angle in both the horizontal and vertical directions, so that the light beam of the second output light field is relatively divergent for short-distance detection, so the receiver 20 can obtain short-distance depth information when receiving the echo light field corresponding to the second output light field, so as to realize functions such as object recognition and obstacle avoidance. It can be understood that the first output light field can have a large divergence angle in the horizontal direction, so that each frame of image data of the depth camera 1 can obtain more environmental depth information, which helps to improve the efficiency of mapping and positioning. It can be understood that, compared with traditional collimating lenses, the microlens array used in the present application can reduce the size of the projector and help reduce costs while achieving the desired collimating effect.

[0061] In addition, in order to avoid mutual interference between the first output light field and the second output light field, the first light source 12 and the second light source 13 in the single projector 10 of the present application are respectively controlled to light up in time division, so as to improve the detection accuracy and facilitate the improvement of the mapping and obstacle avoidance effects. When the first light source 12 is lit, the second light source 13 is not lit; at this time, the light beam emitted by the first light source 12 will first pass through the microlens array 14 to be collimated, and then pass through the diffusion element 15 to expand the beam in the horizontal direction, thereby projecting a light beam with a smaller divergence angle in the vertical direction and a larger divergence angle in the horizontal direction, that is, the first output light field. When the second light source 13 is lit, the first light source 12 is not lit; at this time, the light beam emitted by the second light source 13 will directly pass through the diffusion element 15 to expand the beam in the horizontal and vertical directions at the same time, thereby projecting a light beam with a larger divergence angle in both the horizontal and vertical directions, that is, the second output light field. It is understandable that the first output light field or the second output light field will be reflected to form an echo light field when projected onto the target to be measured, and then the echo light field will be received by the receiver 20 to obtain depth information.

[0062] For example, Figure 3 As shown, the vertical divergence angle V of the first output light field 1 Can be less than 20°, that is, V 1 <20°;The vertical divergence angle V of the second output light field 2 It can be greater than or equal to 40° and less than or equal to 100°, that is, 40°≤V 2 ≤100°.

[0063] Alternatively, if Figure 4 and Figure 5 As shown, the horizontal divergence angle H of the first output light field 1 Can be greater than 100°, that is, H 1 >100°; the horizontal divergence angle H of the second output light field 2 Can be greater than 100°, that is, H 2 >100°. It is understandable that in some outdoor scenes, the horizontal divergence angles of the first output light field and the second output light field may also be less than 100°, because to achieve the same detection distance, outdoor scenes require an output light field with a more concentrated light intensity.

[0064] It is worth noting that, since the vertical divergence angle of the first output light field is smaller than the vertical divergence angle of the second output light field, the light intensity of the first output light field is more concentrated than that of the second output light field. Therefore, the light intensity per unit area of ​​the first output light field is greater than that of the second output light field, so that the first output light field can be projected into a farther area in space relative to the second output light field, which helps to meet the application requirements of map building and navigation. In addition, although the light intensity per unit area of ​​the second output light field is relatively low and can only be projected into a relatively close area in space, it is sufficient to meet the needs of the obstacle avoidance function and can reduce the blind spot of the depth camera 1; at the same time, the second output light field with a lower light intensity per unit area can also reduce the light reflection from the ground, can reduce the multipath interference effect on the obstacle avoidance depth information, help to improve the measurement accuracy of the obstacle avoidance depth information, and facilitate the improvement of the obstacle avoidance effect.

[0065] Optionally, the luminous power of the first light source 12 is greater than the luminous power of the second light source 13, so that the light intensity of the first output light field is greater than the light intensity of the second output light field, so as to further increase the projection distance of the first output light field, thereby improving the detection distance of the mapping scene.

[0066] Optionally, the first light source 12 and the second light source 13 may be implemented as vertical cavity surface emitting lasers (VCSELs) but are not limited thereto. It is understandable that the number of laser points on the first light source 12 may be large, so as to achieve the purpose of long-distance mapping; and the number of laser points on the second light source 13 may be small, so as to achieve the purpose of obstacle avoidance.

[0067] It is worth noting that the depth camera 1 of the present application uses one of the two independent light sources in combination with the microlens array 14 to increase the detection distance to more than ten meters, which well meets the detection distance requirements for the mapping scene. It is understandable that in other examples of the present application, the first light source 12 and the second light source 13 can also be two light-emitting areas arranged at intervals on the same VCSEL, and it is only necessary to ensure that the microlens array 14 is located on the light-emitting path of one of the areas, and this application will not go into details.

[0068] Optionally, the diffusion element 15 may be implemented as a diffuser or a light homogenizer, but is not limited to being implemented as a diffuser. It is understandable that the diffusion element 15 may be implemented as a whole diffuser or light homogenizer with different microstructure areas, or may be composed of two diffusers or light homogenizers with different microstructures.

[0069] For example, Figure 3As shown, the diffusion element 15 may have a first functional area 151 corresponding to the first light source 12 and a second functional area 152 corresponding to the second light source 13, and the optical microstructure surface of the first functional area 151 is different from the optical microstructure surface of the second functional area 152. In this way, the light beam emitted by the first light source 12 will only diverge in the horizontal direction when passing through the first functional area 151 of the diffusion element 15 after being collimated by the microlens array 14, so as to project the first output light field; and the light beam emitted by the second light source 13 will diverge in both the horizontal direction and the vertical direction when passing through the second functional area 152 of the diffusion element 15, so as to project the second output light field. It can be understood that, compared with the use of two independent diffusers or light homogenizers, the diffusion element 15 of the present application uses two areas on the same diffuser or light homogenizer for beam expansion, which is more conducive to the miniaturization of the projector.

[0070] According to the above embodiments of the present application, Figure 6 As shown, the microlens array 14 may include a light-transmitting substrate 141 and a plurality of microlens units 142 arrayed on the light-transmitting substrate 141, and each point light source 120 on the first light-emitting source 12 is located at the back focus of the corresponding microlens unit 142. In this way, the light beam emitted by each point light source 120 on the first light-emitting source 12 will be collimated by the corresponding microlens unit 142, so as to obtain a better collimation effect.

[0071] It is worth noting that in order to avoid crosstalk between the lights emitted by two adjacent point light sources 120, the back focus f of the microlens unit 142 of the present application is usually designed to be relatively small, which easily leads to the risk of interference between the microlens array 14 and the gold wire of the first light source 12. In order to solve this problem, the first light source 12 of the present application is preferably electrically connected to the circuit substrate 11 by reverse gold wire, reducing the risk of interference between the microlens array 14 and the gold wire of the first light source 12. It can be understood that the circuit substrate 11 mentioned in the present application can be, but is not limited to, implemented as a ceramic substrate.

[0072] In addition, the applicant has found through simulation and experiment that the collimation effect of the light beam is highly correlated with the alignment of the microlens array 14, and is particularly sensitive to the XY direction offset of the microlens array 14, and the assembly process needs to be optimized. Since the pre-positioning accuracy of the assembly process of the present application is usually 20um to 30um, which is larger than the size of half of the microlens unit 142, in order to avoid the misalignment that causes some point light sources 120 to be unable to face the microlens unit 142, the number of microlens units 142 in the microlens array 14 of the present application is greater than the number of point light sources 120 on the first light emitting light source 12. For example, the microlens units 142 in the microlens array 14 are at least one more row and one more column than the point light sources 120 on the first light emitting light source 12.

[0073] For example, in the first example of the present application, Figures 3 to 6 As shown, the single projector 10 may further include a bracket 16 arranged on the circuit substrate 11, and the diffusion element 15 and the microlens array 14 are correspondingly assembled on the bracket 16 to ensure that the microlens array 14 is located in the light path between the first light source 12 and the diffusion element 15.

[0074] Alternatively, if Figure 4 and Figure 6 As shown, the bracket 16 includes a base 161 mounted on the circuit substrate 11 and a step group 162 extending inward from the base 161, the diffusion element 15 is fixed to the base 161 to correspond to the first light source 12 and the second light source 13 at the same time, and the microlens array 14 is fixed to the step group 162 to correspond to the first light source 12.

[0075] Alternatively, if Figure 4 As shown, the step group 162 may include a first step 1621 and a second step 1622, and the first step 1621 and the second step 1622 are arranged at intervals along a direction perpendicular to the arrangement direction of the first light source 12 and the second light source 13, and the opposite sides of the light-transmitting substrate 141 are correspondingly attached to the first step 1621 and the second step 1622, so that the microlens unit 142 is suspended on the light-emitting side of the first light source 12.

[0076] Preferably, if Figure 6As shown, the projections of the remaining two sides of the light-transmitting substrate 141 on the first light source 12 are located within the edge range of the first light source 12, so as to avoid the gold wires on the first light source 12, and further reduce the risk of interference between the microlens array 14 and the gold wires of the first light source 12. In other words, the two sides of the light-transmitting substrate 141 close to or far from the second light source 13 can be flush with the edge of the first light source 12, as long as they do not exceed the edge of the first light source 12, so as to ensure that the microlens units 142 on the microlens array 14 can completely cover all the point light sources 120 on the first light source 12, while avoiding the gold wires of the first light source 12 as much as possible to prevent structural interference.

[0077] It is worth noting that Figure 7 As shown, compared with the above-mentioned first example according to the present application, the difference of the single projector 10 according to the second example of the present application is that the step group 162 can further include a third step 1623 away from the second light emitting light source 13, and the remaining edges of the light-transmitting substrate 141 are correspondingly attached to the third step 1623, so that the three edges of the light-transmitting substrate 141 are simultaneously fixed to the step group 162 of the bracket 16, which helps to improve the assembly reliability of the microlens array 14.

[0078] Of course, in the third example of the present application, Figure 8 As shown, the step group 162 may further include a fourth step 1624 away from the first light source 12, and the four sides of the light-transmitting substrate 141 are respectively attached to the first step 1621, the second step 1622, the third step 1623 and the fourth step 1624, so that the four sides of the light-transmitting substrate 141 are simultaneously fixed to the step group 162 of the bracket 16, thereby maximizing the assembly reliability of the microlens array 14. It can be understood that although the light-transmitting substrate 141 of the present application needs to pass over the second light source 13 to be attached to the fourth step 1624, the microlens unit 142 is only arranged in the light-emitting path of the first light source 12, ensuring that the light beam emitted by the second light source 13 only passes through the light-transmitting substrate 141 and is not collimated, and this application will not repeat it.

[0079] In addition, if Fig. 9As shown, compared with the first example, the second example and the third example according to the present application, the difference of the single projector 10 according to the fourth example of the present application is that the single projector 10 can further include a bracket 16 arranged on the circuit substrate 11, the diffusion element 15 is assembled on the bracket 16, and the light-transmitting substrate 141 of the microlens array 14 is attached to the light-emitting surface of the first light-emitting light source 12. In addition, the four sides of the light-transmitting substrate 141 do not extend out or exceed the edge of the first light-emitting light source 12, which can well avoid structural interference with the gold wire of the first light-emitting light source 12.

[0080] It is worth noting that in the above embodiments of the present application, Figure 2 As shown, the first light source 12 and the second light source 13 can be arranged along the vertical direction on the circuit substrate 11. It can be understood that in other examples of the present application, the first light source 12 and the second light source 13 can also be arranged along the horizontal direction on the circuit substrate 11. In addition, the vertical direction mentioned in the present application corresponds to the vertical divergence angle of the output light field; the horizontal direction mentioned in the present application corresponds to the horizontal divergence angle of the output light field.

[0081] For example, Figure 2 and Figure 3 As shown, the receiver 20 and the single projector 10 can be arranged in a vertical direction, and the first light source 12 is located near the receiver 20, while the second light source 13 is located away from the receiver 20. It can be understood that in other examples of the present application, the positions of the first light source 12 and the second light source 13 can be interchanged to make the projection blind area of ​​the second output light field smaller, and this application will not go into details.

[0082] Alternatively, if Figure 2 and Figure 3 As shown, the receiver 20 may include a circuit board 21, a photosensitive component 22 electrically mounted on the circuit board 21, and a receiving lens 23 located on the photosensitive side of the photosensitive component 22, so that the echo light field first passes through the receiving lens 23 to be modulated, and then is received by the photosensitive component 22 to obtain depth information. For example, the photosensitive component 22 of the receiver 20 of the present application may, but is not limited to, use an I-TOF chip, wherein the I-TOF chip is used to collect the phase information of the echo light corresponding to the first output light field to calculate the navigation depth information; and collect the phase information of the echo light corresponding to the second output light field to calculate the obstacle avoidance depth information. In this way, compared with the existing LDS-based mapping navigation vision solution, the depth camera 1 of the present application can use the I-TOF principle to obtain navigation depth information, which is convenient for achieving a 3D mapping effect.

[0083] It is understandable that in other examples of the present application, the photosensitive component 22 of the receiver 20 of the present application may also use a D-TOF chip. In addition, the time of flight (TOF) method measures the time interval t from the emission to the reception of the pulse signal emitted by the projection module (often referred to as the direct time of flight method, Direct TOF, referred to as D-TOF) or the phase generated by the laser going back and forth once to the space to be measured (often referred to as the indirect time of flight method, Indirect TOF, referred to as I-TOF) to achieve the measurement of the three-dimensional structure or three-dimensional contour of the space to be measured.

[0084] Alternatively, if Figure 2 and Figure 3 As shown, the receiver 20 may further include a spacer block 24 fixed to the circuit board 21, the single projector 10 is mounted on the spacer block 24, and the circuit substrate 11 of the single projector 10 is electrically connected to the circuit board 21. In this way, the single projector 10 is correspondingly spaced higher than the receiver 20, so that the single projector 10 and the receiver 20 have flush light surfaces to avoid mutual visual interference. It can be understood that the receiver 20 is higher than the single projector 10 due to the larger receiving lens 23.

[0085] It is worth noting that the single projector 10 can project the first output light field horizontally so as to project it into a farther spatial area, so as to meet the needs of map-building and navigation applications. The single projector 10 can project the second output light field obliquely downward under the action of the second functional area 152 of the diffusion element 15. In this way, the second output light field can be projected onto the ground, which helps to further reduce the blind spot of the depth camera 1 and prevent the mobile robot from being hit due to the inability to identify close objects, thereby affecting the user experience.

[0086] In addition, although the first output light field is projected horizontally forward, it may also form multiple reflections to cause multipath interference, especially under strong light intensity conditions; and the vertical divergence angle of the first output light field projected by the depth camera 1 of the present application is small, which is not only conducive to light spot concentration and achieving higher light intensity, but also can reduce multipath interference of strong light spots, thereby improving the navigation depth measurement accuracy of the depth camera 1 and facilitating the improvement of mapping and navigation effects.

[0087] According to the above-mentioned embodiments of the present application, the depth camera 1 of the present application can control the lighting of the first light source 12 and the second light source 13 through the first drive signal and the second drive signal. The first drive signal and the second drive signal are controlled by the control circuit module on the depth camera 1 to ensure that one and only one light source is lit at the same time.

[0088] It is understandable that according to the above logic, the two light sources are alternately lit to alternately collect strong light frame images and weak light frame images, which can avoid the problem of TOF multipath interference caused by the mutual reflection of light spots between the front wall and the ground below. For example, the image collected by the first drive signal is used to generate the point cloud of the front wall, and the image collected by the second drive signal is used to generate the point cloud of the ground below; at this time, the two point cloud data without multipath interference are fused to obtain a complete three-dimensional point cloud map, which has both information about the front wall for map navigation and information about ground obstacles for obstacle avoidance. It is understandable that when the first light source 12 is lit, the second light source 13 is not lit, and the image frame information collected at this time is a strong light frame image; and when the second light source 13 is lit, the first light source 12 is not lit, and the image frame information collected at this time is a strong light frame image.

[0089] Furthermore, the exposure time of the first driving signal when collecting point clouds is fixed, and a larger exposure is used, so that the optical power of the first light source 12 can be sufficient to illuminate the wall in a farther area, achieving a better map construction and navigation effect; the exposure time of the second driving signal when collecting point clouds can be automatically adjusted according to the actual scene, that is, automatic exposure is used, so that different obstacles on the ground will not be overexposed, and can be stably detected to achieve a better obstacle avoidance effect. It can be understood that in other examples of the present application, when the first driving signal collects point clouds, the first light source 12 can be automatically exposed, as long as it can meet the map construction and navigation requirements, and this application will not go into details.

[0090] Optionally, in order to simplify circuit control, the depth camera 1 of the present application is in the process of alternately collecting strong light frame images and weak light frame images: when a strong light frame image is collected, it is necessary to set a suitable automatic exposure value for the next weak light frame, and this suitable automatic exposure value is given by the last weak light frame depth calculation and will be temporarily stored in the memory; and when a weak light frame image is collected, a fixed exposure value will be set for the next strong light frame. At the same time, when the point cloud data of the two frames of images (i.e., the strong light frame image and the weak light frame image) are calculated, they will be fused and output; this cycle is repeated to obtain navigation depth information and obstacle avoidance depth information in real time.

[0091] It is worth noting that in the depth camera 1 according to the above embodiment of the present application, the first light source 12 and the second light source 13 can be controlled to light up alternately and cyclically one by one, that is, in each cycle, the first light source 12 is only lit once, the second light source 13 is also only lit once, and the first light source 12 and the second light source 13 are lit in time. In other words, the alternating light emission mode of the light source is implemented as: one frame of weak light → one frame of strong light → one frame of weak light → one frame of strong light; this is conducive to reducing the impact of multipath interference, improving the accuracy of depth information, and facilitating map navigation and obstacle avoidance. However, since the first light source 12 and the second light source 13 are lit in time, the frame rate of the strong light frame image and the frame rate of the weak light frame image collected by the depth camera 1 will be reduced, which may affect the obstacle avoidance effect of the mobile robot.

[0092] However, considering that obstacle avoidance has a relatively high frame rate requirement for the depth map (i.e., higher than the frame rate requirement for the depth map for map building and navigation), in other examples of the present application, the first light source 12 and the second light source 13 are alternately cycled and lit one to multiple times, that is, in each cycle, the first light source 12 is only lit once, and the second light source 13 can be lit multiple times. In other words, the alternating light emission mode of the light sources can be implemented as: multiple frames of weak light → one frame of strong light → multiple frames of weak light → one frame of strong light; in this way, although the frame rate of the strong light frame image captured by the depth camera 1 will be further reduced, it can still meet the needs of map building and navigation; while the frame rate of the weak light frame image captured by the depth camera 1 will increase, which will help improve the obstacle avoidance effect of the mobile robot.

[0093] It is worth mentioning that Fig.10 A method for manufacturing a single projector according to an embodiment of the present application is shown, which may include the steps of:

[0094] S100: mounting the microlens array and the diffusion element on the bracket respectively;

[0095] S200: Pre-positioning the bracket and the circuit substrate mounted with the first light source and the second light source by dispensing glue, so that the microlens array is located in the light path between the first light source and the diffusion element;

[0096] S300: Adjusting the bracket relative to the first light source so that each point light source on the first light source is located at the back focus of the corresponding microlens unit on the microlens array; and

[0097] S400: curing the glue to fix the bracket to the circuit substrate to complete the assembly.

[0098] It is worth noting that in the above step S100 of the present application, the microlens array may be mounted first, and then the diffusion element; or, the diffusion element may be mounted first, and then the microlens array.

[0099] Optionally, in the above step S300 of the present application: the position of the bracket can be adjusted relative to the first light source so that the microlens units in the microlens array are aligned one by one with the point light sources in the first light source. It can be understood that the alignment mentioned in the present application refers to the point light source being aligned with the center of the microlens unit in the X and Y directions, and the point light source being located at the back focus position of the microlens unit in the Z direction.

[0100] It is worth mentioning that according to another aspect of the present application, an embodiment of the present application provides a depth information acquisition method, which may include the steps of:

[0101] Controlling the single projector to light up the first light source and the second light source of the single projector in a time-sharing manner;

[0102] When the first light source is illuminated each time, the first input light field is emitted to the micro-lens array of the single projector to be collimated and then projected through the diffusion element of the single projector to project the first output light field;

[0103] When the second light source is illuminated each time, emitting a second input light field to the diffusion element to project a second output light field; and

[0104] The receiver is controlled to receive the echo light field, so as to obtain navigation depth information when the echo light field corresponding to the first output light field is received, and to obtain obstacle avoidance depth information when the echo light field corresponding to the second output light field is received.

[0105] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0106] The above embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A single projector, characterized in that: include: Circuit board; A first light source, the first light source being electrically disposed on the circuit substrate; a second light source, the second light source being electrically disposed on the circuit substrate, and the second light source and the first light source being spaced apart and arranged on the same surface of the circuit substrate; a microlens array, the microlens array being arranged on the light-emitting side of the first light-emitting light source and being used for collimating the light beam emitted by the first light-emitting light source; as well as A diffusion element, wherein the diffusion element is arranged on the light-emitting side of the first light source and the second light source, and the microlens array is located in the light path between the first light source and the diffusion element; the diffusion element is used to expand the light beam collimated by the microlens array in the horizontal direction to form a first output light field, and to expand the light beam emitted by the second light source in the horizontal and vertical directions to form a second output light field with a vertical divergence angle greater than the first output light field.

2. The single-body projector according to claim 1, characterized in that: The first light source and the second light source are both vertical cavity surface emitting lasers; the diffusion element is a diffusion sheet or a light homogenizer.

3. The single-body projector according to claim 1, characterized in that: The diffusion element has a first functional area corresponding to the first light source and a second functional area corresponding to the second light source, and an optical microstructure surface of the first functional area is different from an optical microstructure surface of the second functional area.

4. The single-body projector according to claim 1, characterized in that: The vertical divergence angle of the first output light field is less than 20°, and the vertical divergence angle of the second output light field is greater than or equal to 40° and less than or equal to 100°.

5. The single-body projector according to claim 1, characterized in that: The horizontal divergence angles of the first output light field and the second output light field are both greater than 100°.

6. The single-body projector according to claim 1, characterized in that: The luminous power of the first light source is greater than the luminous power of the second light source.

7. The single-body projector according to any one of claims 1 to 6, characterized in that: The microlens array comprises a light-transmitting substrate and a plurality of microlens units arrayed on the light-transmitting substrate; each point light source on the first light source is located at the back focus of the corresponding microlens unit.

8. The single-body projector according to claim 7, characterized in that: The light-transmitting substrate of the microlens array is attached to the light-emitting surface of the first light source.

9. The single-body projector according to claim 7, characterized in that: The single projector further includes a bracket disposed on the circuit substrate, and the diffusion element and the microlens array are correspondingly assembled on the bracket.

10. The single-body projector according to claim 9, characterized in that: The bracket includes a base mounted on the circuit substrate and a step group extending inward from the base. The diffusion element is fixed to the base, and the microlens array is fixed to the step group.

11. The single-body projector according to claim 10, characterized in that: The step group includes a first step and a second step, the first step and the second step are arranged at intervals along a direction perpendicular to the arrangement direction of the first light source and the second light source, and the opposite sides of the light-transmitting substrate are correspondingly attached to the first step and the second step respectively.

12. The single-body projector according to claim 11, characterized in that: The projections of the remaining two sides of the light-transmitting substrate on the first light source are located within the edge range of the first light source.

13. The single-body projector according to claim 11, characterized in that: The step group further includes a third step away from the second light source and / or a fourth step away from the first light source, and the remaining edge of the light-transmitting substrate is correspondingly attached to the third step and / or the fourth step.

14. A depth camera, characterized in that: include: A single projector as claimed in any one of claims 1 to 13; as well as A receiver is correspondingly arranged on the side of the single projector.

15. A mobile robot, characterized in that include: Robot body; and The depth camera as described in claim 14 is mounted on the robot body, and the depth camera is used to provide navigation depth information and obstacle avoidance depth information for the robot body.

16. A method for manufacturing a single projector, characterized in that: Includes steps: Mounting the microlens array and the diffusion element on the bracket respectively; Pre-positioning the bracket and the circuit substrate mounted with the first light source and the second light source by dispensing glue, so that the microlens array is located in the light path between the first light source and the diffusion element; Adjusting the bracket relative to the first light source so that each point light source on the first light source is located at the back focus of the corresponding microlens unit on the microlens array; as well as The glue is cured to fix the bracket to the circuit substrate to complete the assembly.

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