Three-dimensional sensing system and sweeping robot

Abstract

The embodiment of the invention provides a three-dimensional sensing system and a sweeping robot. The three-dimensional sensing system comprises a light path deflection type projector which comprises a light source module, a polarization splitting prism, a reflecting mirror, a first collimating element, a second collimating element and a diffractive optical element; the light source module comprises a first light-emitting area and a second light-emitting area which emit first polarized light and second polarized light respectively. The polarization splitting prism is arranged on a transmission path of light emitted by the light source module, the first polarized light is transmitted to form a first light path, and the second polarized light is reflected to form a second light path; the reflector is arranged on the second light path and is used for reflecting the reflected second polarized light to the first direction; the first collimating element is arranged in the first direction and is used for collimating the reflected second polarized light; the second collimating element is arranged on the first light path and is used for collimating the transmitted first polarized light; the diffractive optical element is arranged on the collimated light path and used for diffracting the collimated light beam to form a structured light pattern.

Description

Technical Field

[0001] This application relates to the field of structured light technology, and more specifically, to a three-dimensional sensing system and a robotic vacuum cleaner. Background Technology

[0002] 3D structured light technology is an active optical 3D measurement technology. Its core principle is to project a specific, known coded light pattern (such as speckle, stripes, etc.) onto the target object, then use a camera to capture the pattern modulated (deformed) by the object's surface, and finally reconstruct the 3D shape information of the object's surface by calculating the difference between the deformed pattern and the original pattern.

[0003] In existing applications, to obtain richer depth information from the surface of the object being measured or to adapt to different measurement distances and accuracy requirements, it is usually necessary to use two or more independent projectors to project coded patterns with different field of view (FOV) or different speckle densities. This multi-projector approach results in a complex overall system structure, large size, high cost, and high power consumption.

[0004] Furthermore, in situations with strong ambient light (especially those containing infrared components), the light emitted by the projector can easily be drowned out by the ambient light, making it difficult for the receiver to distinguish between signal light and ambient light, resulting in a decreased signal-to-noise ratio and consequently affecting the accuracy and reliability of 3D imaging. Simultaneously, when multiple projectors with unpolarized light sources operate in the same area, their projected patterns may become confused due to a lack of distinguishable feature information, leading to a "multi-projector interference" problem and resulting in depth calculation errors.

[0005] Therefore, there is an urgent need in this field for a compact three-dimensional sensing solution that can effectively resist ambient light and multi-machine interference. Summary of the Invention

[0006] One objective of this application is to provide a new technical solution for a three-dimensional sensing system, which can project structured light patterns with different field of view (FOV) and / or different speckle densities using a single projector, thereby meeting the needs for depth information acquisition at different distances and with different precision.

[0007] Another objective of this application is to provide a new technological solution for a robotic vacuum cleaner.

[0008] In a first aspect, this application provides a three-dimensional sensing system, including an optical path deflector projector, the optical path deflector projector comprising: The light source module includes a first light-emitting area and a second light-emitting area, wherein the first light-emitting area is used to emit first polarized light and the second light-emitting area is used to emit second polarized light; A polarizing beam splitter is disposed on the transmission path of the light emitted by the light source module to split the incident light according to the polarization state, wherein the first polarized light is transmitted to form a first optical path and the second polarized light is reflected to form a second optical path. A reflector, disposed on the second optical path, is used to reflect the second polarized light reflected by the polarizing beam splitter toward the first direction; A first collimating element is disposed on the first optical path and is used to collimate the first polarized light transmitted through the polarizing beam splitter. A second collimating element, disposed in the first direction, is used to collimate the second polarized light reflected by the mirror; and... A diffractive optical element is disposed in the optical path after being collimated by the first collimating element and / or the second collimating element, for diffracting the collimated beam to form a structured light pattern; In this process, by selectively illuminating the first luminous area and / or the second luminous area, the optical path deflector can project structured light patterns with the same or different characteristic parameters, including the field of view (FOV) and / or speckle density.

[0009] Optionally, the polarization directions of the first polarized light and the second polarized light are orthogonal to each other; wherein, the first polarized light is P-polarized light and the second polarized light is S-polarized light.

[0010] Optionally, the first light-emitting area and the second light-emitting area are arranged side by side or staggered on the light source module, and both the first light-emitting area and the second light-emitting area can be controlled independently.

[0011] Optionally, the diffractive optical element is provided as a single element, configured to receive light rays collimated by the first collimating element and the second collimating element; The minimum transverse period Ph and minimum vertical period Pv of the diffractive optical element satisfy the following relationship: Ph=λ / 2sin(arctan(L1 / (2*f3))); Pv=λ / 2sin(arctan(H1 / (2*f3))); Wherein, λ is the wavelength of the light emitted by the light source module, L1 and H1 are the length and width of the light-emitting area of ​​the first light-emitting region, respectively, and f3 is the focal length of the first collimating element.

[0012] Optionally, the length L2 and width H2 of the second light-emitting region satisfy the following relationship: L2=2*f4*tan(arcsin(λ / 2*Ph)); H2=2*f4*tan(arcsin(λ / 2*Pv)); Where f4 is the focal length of the second collimating element.

[0013] Optionally, the first light-emitting region includes a plurality of first light-emitting units arranged in a first array for emitting the first polarized light; The second light-emitting region includes a plurality of second light-emitting units arranged in a second array for emitting the second polarized light; The first array and the second array are arranged alternately, such that when the first light-emitting area and the second light-emitting area are lit at the same time, the speckle spots originating from the first light-emitting unit and the speckle spots originating from the second light-emitting unit projected by the diffractive optical element do not overlap in space.

[0014] Optionally, the arrangement pitch of the second light-emitting units in the second light-emitting area satisfies the following relationship: pitch = 2 * f4 * tan(arctan(B / (2 * Z)), where z is the preset projection distance, f4 is the focal length of the second collimating element, and B is the spacing between the speckle lines generated by the second light-emitting area.

[0015] Optionally, there are two diffractive optical elements, including a first diffractive optical element and a second diffractive optical element, wherein the first diffractive optical element is located on the light exit path of the first collimating element, and the second diffractive optical element is located on the light exit path of the second collimating element; The first diffractive optical element and the second diffractive optical element have different microstructure periods, which results in the structured light patterns projected when the first light-emitting area and the second light-emitting area are lit up respectively having different field of view (FOV).

[0016] Optionally, the minimum transverse period Ph7 and the minimum vertical period Pv7 of the first diffractive optical element satisfy the following relationship: Ph7=λ / 2sin(arctan(L1 / (2*f3))); Pv7=λ / 2sin(arctan(H1 / (2*f3))); Wherein, λ is the wavelength of the light emitted by the light source module, L1 and H1 are the length and width of the light-emitting area of ​​the first light-emitting region, respectively, and f3 is the focal length of the first collimating element.

[0017] Optionally, the minimum transverse period Ph5 and the minimum vertical period Pv5 of the second diffractive optical element satisfy the following relationship: Ph5=λ / 2sin(arctan(L2 / (2*f4))); Pv5=λ / 2sin(arctan(H2 / (2*f4))); Wherein, λ is the wavelength of the light emitted by the light source module, L2 and H2 are the length and width of the light-emitting area of ​​the second light-emitting region, respectively, and f4 is the focal length of the second collimating element.

[0018] Optionally, the three-dimensional sensing system further includes a receiver, which includes at least one photosensitive element configured to receive light reflected from the target object carrying the structured light pattern, for imaging the first polarized light originating from the first emitting region and the second polarized light originating from the second emitting region.

[0019] Optionally, the receiving end includes a first receiver and a second receiver; The first receiver is provided with a first photosensitive element, and a first polarizer is provided in front of the photosensitive path of the first receiver, and the polarization direction of the first polarizer is the same as the polarization direction of the first polarized light. The second receiver is provided with a second photosensitive element, and a second polarizer is provided in front of the photosensitive path of the second receiver, and the polarization direction of the second polarizer is the same as the polarization direction of the second polarized light. The first photosensitive element is used to receive the first polarized light, and the second photosensitive element is used to receive the second polarized light.

[0020] Optionally, the receiving end includes a third receiver and a switchable filter module; The third receiver includes a third photosensitive element and a fourth photosensitive element. The third photosensitive element is used to receive the first polarized light, and the fourth photosensitive element is used to receive the second polarized light. The switchable filter module is configured to selectively place a first polarizer, a second polarizer, or an optically transparent element in front of the photosensitive path of the third receiver; wherein the polarization direction of the first polarizer is the same as the polarization direction of the first polarized light, the polarization direction of the second polarizer is the same as the polarization direction of the second polarized light, and the optically transparent element allows all polarized light to pass through.

[0021] Optionally, the third receiver further includes a polarization beam splitter configured to transmit the first polarized light and reflect the second polarized light; The third photosensitive element is disposed on the transmission light path of the polarization beam splitter; The fourth photosensitive element is disposed on the reflected light path of the polarization beam splitter.

[0022] Optionally, the receiving end includes a fourth receiver, the fourth receiver includes a fifth photosensitive element, and the fifth photosensitive element is a polarization image sensor; The polarization image sensor integrates micro-polarization filters of different directions on multiple photosensitive pixels, including at least a first type of pixel sensitive to the first polarized light and a second type of pixel sensitive to the second polarized light, so as to simultaneously acquire and distinguish image information of the first polarized light and the second polarized light.

[0023] Secondly, this application provides a robotic vacuum cleaner, the robotic vacuum cleaner comprising: The three-dimensional sensing system as described in the first aspect.

[0024] The beneficial effects of this application are as follows: The three-dimensional sensing system proposed in this application adopts an integrated structure of polarization beam splitting and optical path deflection, which efficiently integrates dual emission areas and dual optical paths into a single projector. By selectively illuminating different emission areas, a structured light pattern with a flexibly configurable field of view (FOV) and speckle density can be projected using only one projector. This ensures that the entire three-dimensional sensing system is highly compact while adapting to different detection distances and accuracy scenarios, greatly improving the integration, functional flexibility and environmental adaptability of the three-dimensional sensing system.

[0025] Other features and advantages of this specification will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0026] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of this specification and, together with their description, serve to explain the principles of this specification.

[0027] Figure 1 One of the optical structures and optical path diagrams of the optical path deflection projector for the three-dimensional sensing system provided in the embodiments of this application; Figure 2 The second optical structure and optical path diagram of the optical path deflector projector of the three-dimensional sensing system provided in the embodiments of this application; Figure 3 One of the schematic diagrams of the light source module of the optical path deflection projector of the three-dimensional sensing system provided in the embodiments of this application; Figure 4 A second schematic diagram of the light source module of the optical path deflection projector provided in the embodiment of this application; Figure 5 One of the simulation result diagrams of the three-dimensional sensing system provided in the embodiments of this application; Figure 6 The second simulation result diagram of the three-dimensional sensing system provided in the embodiments of this application; Figure 7 The third simulation result diagram of the three-dimensional sensing system provided in the embodiments of this application; Figure 8 Figure 4 shows the simulation results of the three-dimensional sensing system provided in the embodiments of this application; Figure 9 Figure 5 is a simulation result diagram of the three-dimensional sensing system provided in the embodiments of this application; Figure 10 The optical structure and optical path diagram of a first type of receiver for a three-dimensional sensing system provided in the embodiments of this application; Figures 11 to 13 These are the optical structures and optical path diagrams of the second type of receiver of the three-dimensional sensing system provided in the embodiments of this application under different usage states; Figure 14 The optical structure and optical path diagram of a third receiver of a three-dimensional sensing system provided in the embodiments of this application.

[0028] Explanation of reference numerals in the attached figures: 1. Light source module; 101. First light-emitting area; a. First light-emitting unit; 102. Second light-emitting area; b. Second light-emitting unit; 01. First polarized light; 02. Second polarized light; 2. Reflector; 3. First collimating element; 4. Second collimating element; 5. Second diffractive optical element; 6. Polarizing beam splitter; 7. First diffractive optical element; 8. First receiver; 81. First polarizer; 82. First photosensitive element; 83. First infrared chip; 9. Second receiver; 91. Second polarizer; 92. Second photosensitive element; 93. Second infrared chip; 10. Third receiver; c. First polarizer; d. Second polarizer; e. Optical transparent element; f. Polarizing beam splitter; g. Third photosensitive element; h. Fourth photosensitive element; 11. Fourth receiver; 1101. Fifth photosensitive element. Detailed Implementation

[0029] Various exemplary embodiments of this application will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this application.

[0030] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.

[0031] Technologies and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such technologies and equipment should be considered part of the specification.

[0032] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0033] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0034] The three-dimensional sensing system and the robotic vacuum cleaner provided in the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0035] According to one embodiment of this application, a three-dimensional sensing system is provided, see [link to relevant documentation]. Figure 1 and Figure 2 The three-dimensional sensing system includes an optical path deflecting projector, which comprises: a light source module 1, a polarizing beam splitter 6, a reflector 2, a first collimating element 3, a second collimating element 4, and diffractive optical elements. See also... Figure 3 and Figure 4 The light source module 1 includes a first light-emitting area 101 and a second light-emitting area 102. The first light-emitting area 101 emits first polarized light O1, and the second light-emitting area 102 emits second polarized light O2. A polarizing beam splitter 6 is disposed on the transmission path of the light emitted by the light source module 1 to split the incident light according to its polarization state. The first polarized light O1 is transmitted to form a first optical path, and the second polarized light O2 is reflected to form a second optical path. A reflecting mirror 2 is disposed on the second optical path to reflect the second polarized light O2 reflected by the polarizing beam splitter 6 towards a first direction. A first collimating element 3 is disposed on the first optical path to collimate the first polarized light O1 transmitted by the polarizing beam splitter 6. A second collimating element 4 is disposed in the first direction to collimate the second polarized light O2 reflected by the reflecting mirror 2. A diffractive optical element is disposed on the collimated optical path and configured to diffract the collimated beam to form a structured light pattern. By selectively illuminating the first light-emitting area 101 and / or the second light-emitting area 102, the optical path deflector can project structured light patterns with the same or different characteristic parameters, including the field of view (FOV) and / or speckle density.

[0036] The three-dimensional sensing system provided in this application embodiment has a core optical component: a light path deflector projector located at the projection end. This light path deflector projector is designed with two different optical architectures, which can be found in the respective references. Figure 1 and Figure 2 As shown. From the perspective of optical structure, combined with Figure 1 and Figure 2It can be seen that the optical path deflection projector mainly consists of a light source module 1, a polarizing beam splitter 6, a reflector 2, a first collimating element 3, a second collimating element 4, and at least one diffractive optical element.

[0037] This application provides a highly integrated three-dimensional sensing system, the core of which lies in a newly designed optical path deflection projector. Through a special optical architecture design, the optical path deflection projector integrates functions that traditionally require multiple modules into one unit. The functions and cooperative relationships of the various components of the optical path deflection projector in this application are explained below.

[0038] The light source module 1 constitutes the light-emitting core of the optical path deflection projector, and includes a first light-emitting area 101 and a second light-emitting area 102 that are independent of each other in terms of physical structure and driving logic. The specific configuration of these two light-emitting areas can be found in [reference 1]. Figure 3 and Figure 4 As shown, these two light-emitting areas can be set alternately or side by side.

[0039] See Figure 1 and Figure 2 The first light-emitting region 101 is used to emit light with a first polarization direction, referred to as first polarized light 01, which is, for example, P-polarized light. The second light-emitting region 102 is used to emit light with a second polarization direction orthogonal to the first polarization direction, referred to as second polarized light 02, which is, for example, S-polarized light. Both light-emitting regions can be independently addressed and controlled, and can be selectively illuminated (including illuminating one light-emitting region individually or illuminating both light-emitting regions simultaneously). This control characteristic is the basis for realizing various structured light projection modes.

[0040] In one exemplary embodiment, the light source module 1 may be implemented using a vertical cavity surface-emitting laser (VCSEL) array to provide good polarization characteristics and integration.

[0041] The polarizing beam splitter 6 is disposed on the light output path of the light source module 1 and is used to split the beam according to the polarization state of the incident light. For incident mixed polarized light or unpolarized light, the polarizing beam splitter can efficiently transmit the first polarized light O1 to form a first optical path and reflect the second polarized light O2, which is orthogonal to the polarization direction of the first polarized light, to form a second optical path, thereby realizing the spatial separation of beams from different light-emitting regions.

[0042] In one exemplary embodiment, the polarizing beam splitter 6 is, for example, composed of two right-angled triangular prisms bonded together, and a beam-splitting film is disposed on the bonding surface of the two right-angled triangular prisms, the beam-splitting film being, for example, a semi-transparent and semi-reflective film. The polarizing beam splitter 6 is, for example, cube-shaped.

[0043] See Figure 1 and Figure 2 The reflector 2 is located on the second optical path (the propagation direction of the second polarized light O2) and is used to deflect the optical path. The reflector 2 is used to receive the second polarized light O2 (the second polarized light O2 is, for example, S-polarized light) reflected by the polarizing beam splitter 6 and guide the beam to propagate in the first direction. This optical path folding design can effectively compress the volume of the optical path deflecting projector and allow the second optical path to be turned parallel to the first optical path or converge as needed. It is a key component in achieving a compact layout of the entire optical path deflecting projector.

[0044] In one exemplary embodiment, the inclined surface of the reflector 2 is its reflecting surface, see [reference needed]. Figure 1 and Figure 2 As shown.

[0045] In this application, the first collimating element 3 and the second collimating element 4 are used to collimate two polarized beams (the two polarized beams are the first polarized beam O1 and the second polarized beam O2, respectively), converting the divergent beam into a parallel beam or an approximately parallel beam, which can provide a necessary foundation for the efficient operation of subsequent diffractive optical elements.

[0046] The second collimating element 4 is disposed in the optical path (the turning optical path of the second optical path) in the first direction, and is used to collimate the second polarized light O2 (the second polarized light O2 is, for example, S-polarized light) reflected by the reflector 2. The first collimating element 3 is disposed in the first optical path, and is used to collimate the first polarized light O1 transmitted through the polarizing beam splitter 6. These two beams are processed by independent collimating elements, so that their divergence angles can be controlled separately, thereby providing the possibility of adjusting the field of view (FOV) and speckle density of the emitted structured light pattern.

[0047] In one exemplary embodiment, the first collimating element 3 may be a short-focal-length collimating lens, from Figure 1 and Figure 2 It can be seen that the first polarized light 01 travels a shorter path. The second collimating element 4 can be a long-focal-length collimating lens, from... Figure 1 and Figure 2 It can be seen that the second polarized light 02 travels a slightly longer path to accommodate the difference in optical path length and different collimation requirements.

[0048] The diffractive optical element (DOE) is positioned in the collimated optical path to diffract the incident collimated laser beam, generating a structured light pattern with specific encoded information (such as random speckle). The micro / nano structures on the surface of the DOE modulate the light wave, converting the uniformly collimated beam into a preset distribution pattern and projecting it onto the surface of the target object. Both the collimated first polarized light O1 and the second polarized light O2 ultimately strike the DOE for processing.

[0049] In one embodiment of this application, the diffractive optical element may be configured as a single element, see [link to relevant documentation]. Figure 1 It can handle two collimated beams.

[0050] In another embodiment of this application, the diffractive optical element may also consist of two diffractive optical elements, including a first diffractive optical element 7 and a second diffractive optical element 5, see [link to relevant documentation]. Figure 2 The first diffractive optical element 7 is used to process the first polarized light O1, and the second diffractive optical element 5 is used to process the second polarized light O2. That is, two diffractive optical elements are used to process the two beams respectively to achieve different optical functions and output characteristics.

[0051] Through the coordinated operation of the above-mentioned components, the three-dimensional sensing system provided in this application achieves the following significant beneficial effects: High integration and miniaturization: It adopts an integrated structure of polarization beam splitting and optical path folding, integrating dual light emission areas and dual optical paths into a single projector, replacing the complex architecture of traditional multiple projectors in parallel, significantly simplifying the system structure and effectively reducing the overall size, cost and power consumption.

[0052] Diverse functions and flexible control: By selectively illuminating the two light-emitting areas (such as the first light-emitting area 101 and the second light-emitting area 102) of the light source module 1, including illuminating one light-emitting area alone or illuminating both light-emitting areas at the same time, the optical path deflection projector can be controlled to output structured light patterns that are the same or different in terms of field of view (FOV) and speckle density. This allows the same projector to achieve both large-area low-precision scanning and small-area high-precision detection, flexibly adapting to the diverse needs of different measurement scenarios for distance, accuracy and field of view.

[0053] Enhanced anti-interference capability: Since the three-dimensional sensing system itself generates and processes two types of orthogonally polarized light, this provides a hardware foundation for the receiver to effectively suppress ambient stray light, improve the signal-to-noise ratio, and distinguish the projected light from different devices to solve the "multi-device interference" problem through polarization filtering technology.

[0054] This application provides a highly integrated, multifunctional, and high-performance three-dimensional sensing system solution that achieves multi-mode projection and anti-interference capabilities under a single projector condition.

[0055] In existing 3D sensing systems, in order to obtain richer depth information of object surfaces, it is usually necessary to set up two or more independent projectors to emit different coded patterns. This results in a complex system structure, large size, high cost, and difficulty in achieving flexible configuration and control.

[0056] To address the aforementioned issues, this application proposes a novel optical path deflection projector structure, which enables the generation of structured light patterns with multiple field of view (FOV) and multiple speckle densities using only a single projector. This allows for adaptive acquisition of depth information based on accuracy requirements under different field of view conditions, significantly improving system integration and functionality.

[0057] Furthermore, in application scenarios with strong ambient light, the projected light in traditional solutions is easily affected by stray light, leading to a decrease in the signal-to-noise ratio and severely impacting the quality of 3D imaging. This application addresses this issue by setting up light-emitting areas in the light source module 1 that emit polarized light with different polarization directions. This imbues the projected light with its own polarization characteristics, enabling the receiver to effectively distinguish between signal light and ambient light through polarization filtering. This fundamentally suppresses stray light interference and improves the robustness and reliability of the system in complex lighting environments.

[0058] The three-dimensional sensing system provided in this application embodiment can be widely adapted to many technical fields that have an urgent need for three-dimensional environmental perception, such as robotic vacuum cleaners, service robots, autonomous driving, AR / VR, and intelligent monitoring, and has a very broad application prospect.

[0059] See some examples in this application. Figure 1 and Figure 2 The polarization directions of the first polarized light O1 and the second polarized light O2 are orthogonal to each other. Specifically, the first polarized light O1 is P-polarized light, and the second polarized light O2 is S-polarized light.

[0060] This design fully utilizes the fundamental difference in polarization characteristics between P-polarized and S-polarized light. The selection of orthogonal polarization states enables subsequent optical components, especially the polarizing beam splitter 6, to efficiently and accurately separate the two beams according to their polarization directions. Specifically, P-polarized light is transmitted through the beam-splitting film (e.g., a semi-transparent, semi-reflective film) in the polarizing beam splitter 6, while S-polarized light is reflected by the beam-splitting film (e.g., a semi-transparent, semi-reflective film) in the polarizing beam splitter 6. This characteristic forms the basis for constructing a compact optical path deflection structure (i.e., an optical path deflection projector).

[0061] Therefore, using orthogonal P-polarized and S-polarized light is not only key to achieving spatial separation of the optical path, but also lays a crucial foundation for the three-dimensional sensing system to suppress stray light interference and improve the signal-to-noise ratio at the receiving end through polarization screening.

[0062] See some examples in this application. Figure 3 and Figure 4 The first light-emitting area 101 and the second light-emitting area 102 are arranged side by side or staggered on the light source module 1, and both the first light-emitting area 101 and the second light-emitting area 102 can be controlled independently.

[0063] In the example provided in this application, the light source module 1 is designed to include a first light-emitting area 101 and a second light-emitting area 102 that can be controlled independently. These two light-emitting areas can be designed as follows: Figure 4 The first light-emitting area 101 and the second light-emitting area 102 are arranged side by side as shown. Of course, the first light-emitting area 101 and the second light-emitting area 102 can also be arranged as shown... Figure 3 The alternating arrangement shown.

[0064] The first light-emitting region 101 is used to emit a first polarized light 01, which is, for example, P-polarized light. The second light-emitting region 102 is used to emit a second polarized light 02, which is, for example, S-polarized light. The polarization directions of these two polarized lights are orthogonal to each other, providing a basis for subsequent polarization beam splitting and optical path control.

[0065] Specifically, in a side-by-side arrangement, see [link to relevant documentation]. Figure 4 The first light-emitting area 101 and the second light-emitting area 102 of the light source module 1 are arranged adjacently and do not overlap. This arrangement facilitates clear separation of the optical path and has the advantage of simple layout control. In other words, in a side-by-side arrangement, see... Figure 4 The first light-emitting area 101 and the second light-emitting area 102 are arranged as spatially separated independent blocks. This method avoids physical overlap between the light-emitting areas, making the layout design, electrode leads and drive control simpler, and helping to reduce process complexity and manufacturing costs.

[0066] Specifically, in the staggered arrangement configuration, see Figure 3 The light-emitting units in the two light-emitting areas of the light source module 1, such as the first light-emitting unit a and the second light-emitting unit b, are spatially staggered. This layout design ensures that when the two light-emitting areas are lit simultaneously, the light spot patterns formed in the target scene after projection by the optical system are staggered and avoid overlapping, thus fusing to form a structured light pattern with a higher speckle density. Regarding the staggered arrangement, this layout can significantly reduce the overall area of ​​the light source module 1, which is beneficial for achieving system miniaturization and integration, and is especially suitable for compact devices with strict size limitations, such as robotic vacuum cleaners.

[0067] Regardless of the arrangement, both the first luminous area 101 and the second luminous area 102 support independent addressing and drive control. This feature is the basis for realizing various projection modes, including but not limited to: illuminating only the first luminous area 101, illuminating only the second luminous area 102, or illuminating both luminous areas simultaneously. Users can flexibly select the working mode through external commands, thereby adjusting the field of view (FOV) and speckle density of the projected structured light pattern to adapt to the three-dimensional perception needs of different distances, precisions, and field of view ranges.

[0068] See some examples in this application. Figure 1 The diffractive optical element is configured as a single unit, capable of receiving light rays collimated by the first collimating element 3 and the second collimating element 4. The minimum transverse period Ph and the minimum vertical period Pv of the diffractive optical element satisfy the following relationship: Ph=λ / 2sin(arctan(L1 / (2*f3)))(1); Pv=λ / 2sin(arctan(H1 / (2*f3)))(2); Wherein, λ is the wavelength of the light emitted by the light source module 1, L1 and H1 are the length and width of the light emission size of the first light emission area 101, respectively, and f3 is the focal length of the first collimating element 3.

[0069] See the examples provided in this application. Figure 1 The diffractive optical element is configured as a single unit, which can be used to receive light collimated by the first collimating element 3 and the second collimating element 4. The minimum transverse period Ph and minimum vertical period Pv of this single diffractive optical element are determined by the following relationships: Ph = λ / 2sin(arctan(L1 / (2*f3))) and Pv = λ / 2sin(arctan(H1 / (2*f3))); where λ is the wavelength of the light emitted by the light source module 1, L1 and H1 are the length and width of the first light-emitting area 101, respectively, and f3 is the focal length of the first collimating element 3. The significance of this design relationship is: The ratios (L1 / 2*f3) and (H1 / 2*f3) reflect the tangent values ​​of the angle subtended by half the size of the first emitting region 101 with respect to the center of the first collimating element 3. By performing arctangent and sine calculations, the maximum diffraction angle θ of the collimated beam can be derived. Finally, based on the grating equation, λ / (2sin(θ)) gives the critical value of the minimum microstructure period required to achieve this maximum diffraction angle.

[0070] By determining the periodic parameters of the diffractive optical element through the above relationship, it can be ensured that when the first light-emitting area 101 is lit, the first polarized light 01 (e.g., P-polarized light) emitted by it is collimated by the first collimating element 3 and diffracted by the diffractive optical element, and the resulting structured light pattern can completely cover the preset field of view (FOV), while maintaining a high light energy utilization rate and a uniform speckle distribution, providing a reliable optical basis for high-precision three-dimensional perception at different distances.

[0071] Formulas (1) and (2) in this example ensure that the microstructure period of the diffractive optical element is precisely designed so that it can be well matched with the emission size (L1, H1) and focal length f3 of the first emission region 101.

[0072] See some examples in this application. Figure 3 and Figure 4 The length L2 and width H2 of the second light-emitting area 102 satisfy the following relationship: L2=2*f4*tan(arcsin(λ / 2*Ph))(3); H2=2*f4*tan(arcsin(λ / 2*Pv))(4); Where f4 is the focal length of the second collimating element 4.

[0073] See the example provided in this application. Figure 3 and Figure 4 To ensure that the structured light patterns generated by the first light-emitting area 101 and the second light-emitting area 102, after being emitted from the same diffractive optical element and projected by the same optical element, have the same field of view (FOV) and can be correctly stitched together, the light-emitting size of the second light-emitting area 102 is limited as follows: The length L2 and width H2 of the second light-emitting area 102 must satisfy the following relationship: L2 = 2 * f4 * tan(arcsin(λ / 2 * Ph)), H2 = 2 * f4 * tan(arcsin(λ / 2 * Pv)); where f4 is the focal length of the second collimating element 4, λ is the emitted light wavelength of the light source module 1, and Ph and Pv are the minimum transverse and vertical periods of the diffractive optical element, respectively. The significance of this design relationship is: (λ / 2*Ph) and (λ / 2*Pv) originate from the grating equation, and their calculation results reflect the specific diffraction angle that the diffraction optical element can produce at the designed wavelength. The diffraction angle θ itself can be obtained through arcsin operation, and then the required size (L2 / 2 and H2 / 2) of the emitting area under half-angle θ illumination can be deduced through tangent operation and focal length f4 conversion.

[0074] This design ensures that when the second light-emitting area 102 is lit, its light-emitting size matches the focal length f4 of the second collimating element 4, so that the collimated beam can be diffracted by the diffractive optical element at the expected diffraction angle. Ultimately, the pattern projected by the second path light, i.e., the second polarized light 02 (such as S-polarized light), has the same field of view (FOV) as the pattern of the first path light, i.e., the first polarized light 01 (such as P-polarized light). This achieves the ability to process dual-path light and output a correctly stitched unified projection using only a single diffractive optical element.

[0075] It should be noted that, in this application, the periods Ph and Pv of the diffractive optical element can be determined by the luminous size of the first luminous region 101 and the focal length f1 of the first collimating element 3. Alternatively, the periods Ph and Pv of the diffractive optical element can also be designed to be determined by the luminous region size of the second luminous region 102 and the focal length f2 of the second collimating element 4. In this case, the size of the first luminous region 12 needs to be further determined based on the determined Ph and Pv. The specific design can be flexible and tailored to requirements.

[0076] In this example of the application, the period (Ph, Pv) and wavelength (λ) of the diffractive optical element are set to known constants. By deducing the maximum diffraction angle that the diffractive optical element can produce, the required light source, i.e., the light-emitting size of the second light-emitting region 102, should be calculated.

[0077] In Embodiment 1 provided in this application, see Figure 1 When the first light-emitting area 101 and the second light-emitting area 102 of the light source module 1 are lit, the optical path deflector projector can project two structured light patterns with the same field of view (FOV) but different or the same point density. Specifically, see... Figure 1 When the first light-emitting area 101 is lit, its light-emitting size is L1*H1. The P-polarized light emitted by the first light-emitting area 101 is projected onto the corresponding first collimating element 3. At this time, the focal length of the first collimating element 3 is set to f3. Based on this, according to the grating equation, we get: Ph=λ / 2sin(arctan(L1 / (2*f3)))(1); Pv=λ / 2sin(arctan(H1 / (2*f3)))(2); Where Ph and Pv are respectively Figure 1 The minimum transverse period and minimum vertical period of the diffractive optical element are shown in the figure; The first collimating element 3 and the second collimating element 4 share a single diffractive optical element. To ensure correct pattern stitching, the luminous size of the second luminous region 102 must meet the following conditions: L2=2*f4*tan(arcsin(λ / 2*Ph))(3); H2=2*f4*tan(arcsin(λ / 2*Pv))(4); Where f4 is the focal length of the second collimating element 4.

[0078] It should be noted that the focal length of the first collimating element 3 corresponding to the first light-emitting area 101 of the light source module 1 is small, so the projected pattern is suitable for low-precision surface detection or long-distance three-dimensional perception; the focal length of the second collimating element 4 corresponding to the second light-emitting area 102 of the light source module 1 is large, so the generated pattern is suitable for high-precision surface reconstruction or close-range depth information acquisition with higher detail requirements.

[0079] See Figure 5 , Figure 5 The simulation results show the case where the same field of view (FOV) is projected, but the point density differs. Specifically, at the same projection distance, the projected area sizes covered by the two modes differ. Figure 5 The simulation shows that the black areas remain consistent, but it is clearly observed that the speckle distribution density after the second luminous area 102 is lit is significantly higher than that when the first luminous area 101 is lit. This simulation verifies that the three-dimensional sensing system of this application can flexibly output different point density patterns using only a single projector, thereby enabling the system to adaptively select the working mode according to different accuracy requirements in practical applications, thus improving the functional integration and application adaptability of the three-dimensional sensing system.

[0080] See Figure 6 , Figure 6 The simulation results show the same field of view (FOV) and the same dot density. By adjusting the distribution density or illumination density of the light-emitting units in the first light-emitting area 101 and the second light-emitting area 102, another working mode can be simulated and verified. At the same projection distance, when the two light-emitting areas are illuminated respectively, the projected structured light pattern not only has the same field of view (FOV) but also the same dot density. Specifically, from the simulation results... Figure 6 It can be observed that the projection area covered by the pattern differs between the two modes. Figure 6 The results show that the black areas are of uniform size, and the spatial distribution density of the speckles is not significantly different. This result confirms that by purposefully designing the arrangement of the light-emitting units within the light-emitting area, it is possible to produce a projection pattern with matched speckle density in two light-emitting areas while keeping the field of view constant.

[0081] Figure 5 and Figure 6 The simulation results demonstrate the high flexibility of optical path deflection projectors in pattern design. Diverse output mode configurations can be achieved on a single projector simply by adjusting the internal structure of each emitting zone, without altering the optical components.

[0082] See some examples in this application. Figure 3 The first light-emitting region 101 includes a plurality of first light-emitting units a arranged in a first array for emitting the first polarized light O1. The second light-emitting region 102 includes a plurality of second light-emitting units b arranged in a second array for emitting the second polarized light O2. The first array and the second array are staggered, such that when the first light-emitting region 101 and the second light-emitting region 102 are simultaneously illuminated, the speckle patterns originating from the first light-emitting units a and the speckle patterns originating from the second light-emitting units b projected by the diffractive optical element do not overlap in space.

[0083] It should be noted that, Figure 7 What is shown is Figure 3 In a simulated partial structured light pattern where the first luminous region 101 and the second luminous region 102 are alternately arranged, the speckle pattern formed by the first luminous region 101 is designated as the first speckle pattern S1, and the speckle pattern formed by the second luminous region 102 is designated as the second speckle pattern S2. Figure 7 It can be seen that the first speckle S1 and the second speckle S2 are staggered.

[0084] In this example of the application, see Figure 3 The first light-emitting area 101 of the light source module 1 includes a plurality of first light-emitting units a arranged in a first array, which can be used to emit first polarized light O1. The second light-emitting area 102 includes a plurality of second light-emitting units b arranged in a second array, which can be used to emit second polarized light O2. The first array and the second array are not simply side by side, but are arranged in a staggered manner in space. The purpose of this staggered layout is that when the first light-emitting area 101 and the second light-emitting area 102 are lit at the same time, the light from different light-emitting units (such as first light-emitting unit a and second light-emitting unit b) is modulated by the subsequent optical system and diffractive optical elements. In the speckle pattern formed on the target scene, the first speckle S1 generated by the first light-emitting unit a and the second speckle S2 generated by the second light-emitting unit b are spatially staggered and do not overlap with each other. See [reference needed] Figure 7 .

[0085] See also the example of this staggered layout. Figure 7 The speckle patterns of the two different light-emitting unit arrays complement each other in space, effectively fusing into a structured light pattern with a speckle density significantly higher than that produced by any single light-emitting region.

[0086] This example combines the staggered arrangement of different light-emitting units with polarization characteristics, which not only increases the pattern density but also helps to lay the foundation for anti-interference function, demonstrating the high integration and intelligence of the design in this application.

[0087] See some examples in this application. Figure 7 The arrangement pitch of the second light-emitting unit b in the second light-emitting area 102 satisfies the following relationship: pitch = 2 * f4 * tan(arctan(B / (2 * Z)), where z is the preset projection distance, f4 is the focal length of the second collimating element 4, and B is the spacing between the speckle lines generated by the second light-emitting area 102.

[0088] In Embodiment 2 of this application, the first light-emitting area 101 and the second light-emitting area 102 of the light source module 1 are simultaneously illuminated. To achieve high-quality image projection, the arrangement of the light-emitting units in these two areas requires a specific design to avoid overlap of speckles from different sources in the final projected structured light pattern. In Embodiment 2, there is also only one diffractive optical element, the optical architecture of which can be found in [reference needed]. Figure 1 The optical design parameters of the diffractive optical element and the method for determining the luminous size of the two luminous regions are the same as those in Embodiment 1 above, and will not be described again here.

[0089] The structured light pattern formed by projection contains two types of speckles (also known as light spots): for example, a first speckle S1 originating from the first light-emitting area 101 and a second speckle S2 originating from the second light-emitting area 102. To avoid overlap of these two types of speckles, the arrangement of the light-emitting units in the two light-emitting areas must satisfy specific geometric relationships. The following uses a regular arrangement as an example to illustrate its design method: First, the arrangement of the first light-emitting unit a in the first light-emitting area 101 is designed, and the spatial distribution of the first speckle S1 projected by it is determined through optical simulation. The distance between two adjacent rows of first speckle S1 is recorded as A. Second, according to the system requirements, the target value B of the speckle row spacing generated by the second light-emitting area 102 is set. Then, the arrangement spacing pitch of the light-emitting units in the second light-emitting area 102 must satisfy the relationship: pitch=2*f4*tan(arctan(B / (2*Z)), where z is the preset projection distance and f4 is the focal length of the second collimating element 4.

[0090] The above design ensures that when the two light-emitting areas are lit simultaneously, the speckles they produce do not overlap on the projection surface and maintain a consistent field of view (FOV).

[0091] See Figure 8 , Figure 8 The simulation results show the formation of a high-density dual-feature information pattern. According to... Figure 8Simulation results show that, after being collimated by two collimating elements (first collimating element 3 and second collimating element 4), the beam can form superimposed but non-overlapping structured light patterns within the same field of view (FOV) when passing through the same diffractive optical element. When the two emitting regions are lit simultaneously, the P-polarized light pattern generated by the first emitting region 101 and the S-polarized light pattern generated by the second emitting region 102 are precisely interleaved in space.

[0092] See Figure 8 The rightmost diagram shows a structured light pattern that simultaneously possesses both high speckle density and orthogonal polarization characteristics. Projecting both polarization patterns onto the surface of a target object significantly enriches the optical encoding information of that surface. During depth calculation, the depth maps corresponding to P-polarized and S-polarized light can be reconstructed separately and fused. This design not only effectively suppresses interference from ambient stray light but also fundamentally solves the problem of mutual interference when multiple devices work together, significantly improving the accuracy of the 3D sensing system.

[0093] See some examples in this application. Figure 2 The diffractive optical elements are configured in pairs, including a first diffractive optical element 7 and a second diffractive optical element 5. The first diffractive optical element 7 is located on the light exit path of the first collimating element 3, and the second diffractive optical element 5 is located on the light exit path of the second collimating element 4. The microstructure periods of the first diffractive optical element 7 and the second diffractive optical element 5 are different, resulting in different field of view (FOV) of the structured light patterns projected when the first luminous region 101 and the second luminous region 102 are illuminated.

[0094] In this example of the application, see Figure 2 The optical path deflector projector employs a configuration of two diffractive optical elements, specifically a first diffractive optical element 7 and a second diffractive optical element 5. In this example configuration, the optical paths are completely separated and processed independently, as described below: The first diffractive optical element 7 is disposed on the light output path of the first collimating element 3, and is responsible for diffractively modulating the first polarized light O1 after it is transmitted through the polarizing beam splitter 6 and collimated by the first collimating element 3.

[0095] The second diffractive optical element 5 is disposed on the light output path of the second collimating element 4, and is responsible for diffractively modulating the second polarized light O2 after it has been reflected by the polarizing beam splitter 6, reflected by the mirror 2, and collimated by the second collimating element 4.

[0096] The core of this example is that the first diffractive optical element 7 and the second diffractive optical element 5 are designed with different microstructure periods. According to the principle of optical diffraction, the period of the diffractive optical element directly determines the angle at which the light beam is diverged, that is, it determines the field of view (FOV) of the projected pattern.

[0097] Therefore, when the first light-emitting area 101 is lit up alone, the first polarized light 01 emitted by it is first transmitted through the polarization beam splitter 6, then collimated by the first collimating element 3, and then diffracted by the first diffractive optical element 7. At this time, a structured light pattern with a first field of view FOV1 will be projected.

[0098] When the second light-emitting area 102 is lit alone, the second polarized light 02 emitted by it is first reflected by the polarizing beam splitter 6, then reflected by the mirror 2, and then collimated by the second collimating element 4. After being diffracted by the second diffractive optical element 5, a structured light pattern with a first field of view FOV2 will be projected.

[0099] By designing the periods of the two diffractive optical elements, FOV1 can be made ≠ FOV2. This scheme enables a single projector to output two different field-of-view patterns, thus allowing for flexible adaptation to different scenario requirements such as wide-angle search and telephoto detail without the need for mechanical movement or the use of multiple projection modules.

[0100] See Figure 2 In the optical path deflection projector, the two optical paths (from the light-emitting area to the diffractive optical element) are completely independent, and can be optimized for their respective target FOVs (e.g., selecting collimating elements with different focal lengths and diffractive optical elements with different periods). This avoids the optical design compromises in a single diffractive optical element scheme and can achieve better pattern uniformity and energy efficiency.

[0101] In some examples of this application, the minimum transverse period Ph7 and the minimum vertical period Pv7 of the first diffractive optical element 7 satisfy the following relationship: Ph7=λ / 2sin(arctan(L1 / (2*f3)))(5); Pv7=λ / 2sin(arctan(H1 / (2*f3)))(6); Wherein, λ is the wavelength of the light emitted by the light source module 1, L1 and H1 are the length and width of the light emission size of the first light emission area 101, respectively, and f3 is the focal length of the first collimating element 3.

[0102] In some examples of this application, the minimum transverse period Ph5 and the minimum vertical period Pv5 of the second diffractive optical element 5 satisfy the following relationship: Ph5=λ / 2sin(arctan(L2 / (2*f4)))(7); Pv5=λ / 2sin(arctan(H2 / (2*f4)))(8); Wherein, λ is the wavelength of the light emitted by the light source module 1, L2 and H2 are the length and width of the light emission size of the second light emission area 102, respectively, and f4 is the focal length of the second collimating element 4.

[0103] In order to precisely control the emitted light field in the two diffractive optical element schemes, the microstructure period of the first diffractive optical element 7 and the second diffractive optical element 5 was designed.

[0104] The minimum period (Ph7, Pv7) of the first diffractive optical element 7 is determined based on the light emission size (L1, H1) of the first light-emitting region 101 and the focal length f3 of the first collimating element 3. This design ensures that when the first light-emitting region 101 is lit, the light emitted by it is efficiently diffracted and forms the desired field of view (such as FOV1).

[0105] Similarly, the minimum period (Ph5, Pv5) of the second diffractive optical element 5 is determined based on the emission size (L2, H2) of the second emitting region 102 and the focal length f4 of the second collimating element 4. This design ensures that when the second emitting region 102 is lit, the light emitted by it can form another expected field of view (FOV2).

[0106] Both of these relationships originate from the grating equation, and their significance lies in determining the aperture angle of the beam by the ratio of the half-size of the emitting region to the focal length of the corresponding collimating element, such as (L1 / (2*f3),) and then deriving the minimum microstructure period required to achieve the target diffraction angle. By independently designing different period parameters for the two optical paths, the realization of two different FOV functions is ensured, and each optical path can maintain high diffraction efficiency and good pattern quality.

[0107] In Embodiment 3 provided in this application, when the first light-emitting area 101 and the second light-emitting area 102 of the light source module 1 are lit respectively, the optical path deflector projector can project two structured light patterns with different FOVs. In this Embodiment 3, the first collimating element 3 corresponds to the first diffractive optical element 7, and the second collimating element 4 corresponds to the second diffractive optical element 5. The two light-emitting areas in this Embodiment 3 can be placed alternately or side-by-side, as described in the respective embodiments. Figure 3 and Figure 4 The two light-emitting areas are illuminated respectively. When the first light-emitting area 101 is illuminated, the light-emitting size is L1*H1, and the focal length of the corresponding first collimating element 3 is f3. According to the grating equation, the minimum transverse period Ph7 and the minimum vertical period Pv7 of the first diffractive optical element 7 satisfy the following relationship: Ph7=λ / 2sin(arctan(L1 / (2*f3)))(5); Pv7=λ / 2sin(arctan(H1 / (2*f3)))(6); Wherein, λ is the wavelength of the light emitted by the light source module 1, L1 and H1 are the length and width of the light emission size of the first light emission area 101, respectively, and f3 is the focal length of the first collimating element 3.

[0108] When the second light-emitting region 102 is lit, the light-emitting size is L2*H2, and the focal length of the corresponding second collimating element mirror 4 is f4. According to the grating equation, the minimum transverse period Ph5 and the minimum vertical period Pv5 of the second diffractive optical element 5 satisfy the following relationship: Ph5=λ / 2sin(arctan(L2 / (2*f4)))(7); Pv5=λ / 2sin(arctan(H2 / (2*f4)))(8); Wherein, λ is the wavelength of the light emitted by the light source module 1, L2 and H2 are the length and width of the light emission size of the second light emission area 102, respectively, and f4 is the focal length of the second collimating element 4.

[0109] In the two diffractive optical element implementations of Example 3, the beam collimated by the first collimating element 3 is diffracted by the first diffractive optical element 7, while the beam collimated by the second collimating lens 4 is diffracted by the second diffractive optical element 5. Because the two diffractive optical elements have independent, customizable microstructure parameters, they can produce two distinctly different output characteristics.

[0110] Specifically, this embodiment 3 can project two structured light patterns with different field of view (FOV) and different speckle distributions. See [link to documentation]. Figure 9 The simulation results shown demonstrate that the specific relationship between the two field of view angles can be flexibly set according to actual application requirements: the field of view angle FOV5 determined by the second diffractive optical element 5 can be greater than, equal to, or less than the field of view angle FOV7 determined by the first diffractive optical element 7. This design provides great flexibility, allowing for customization of optical output according to specific application scenarios (such as wide-angle search and narrow-angle precision detection).

[0111] In summary, this design enables a single projector to switch between two different operating modes according to instructions, thereby achieving the function of acquiring depth information under different fields of view, significantly improving the adaptability and practicality of the 3D sensing system.

[0112] See some examples in this application. Figures 10 to 14The three-dimensional sensing system further includes a receiver, which includes at least one photosensitive element configured to receive light carrying the structured light pattern reflected from the target object for imaging the first polarized light O1 originating from the first light-emitting area 101 and the second polarized light O2 originating from the second light-emitting area 102.

[0113] See the examples in this application. Figures 10 to 14 The three-dimensional sensing system also integrates a receiver. The receiver includes at least one photosensitive element, which functions to receive light reflected from the surface of the target object, carrying structured light pattern modulation information, and to image it.

[0114] It is worth noting that the basic architecture of the receiver is designed to process two different polarized lights, enabling it to sense and image the first polarized light O1 (e.g., P-polarized light) originating from the first emitting region 101 and the second polarized light O2 (e.g., S-polarized light) originating from the second emitting region 102. This basic design provides a hardware platform for the subsequent implementation of various advanced signal separation and anti-interference technologies, and is the core foundation for the system to achieve polarization differentiation.

[0115] See some examples in this application. Figure 10 The receiving end includes two receivers: a first receiver 8 and a second receiver 9. The first receiver 8 has a first photosensitive element 82 inside, and a first polarizer 81 is positioned before the photosensitive path of the first receiver 8, with the polarization direction of the first polarizer 81 being the same as the polarization direction of the first polarized light O1. The second receiver 9 has a second photosensitive element 92 inside, and a second polarizer 91 is positioned before the photosensitive path of the second receiver 9, with the polarization direction of the second polarizer 91 being the same as the polarization direction of the second polarized light O2. The first photosensitive element 82 is used to receive the first polarized light O1, and the second photosensitive element 92 is used to receive the second polarized light O2.

[0116] This example provides an optical structure design for the receiver in the three-dimensional sensing system of this application, specifically: The receiving end is equipped with two receivers: a first receiver 8 and a second receiver 9, see [link to relevant documentation]. Figure 10 The first receiver 8 and the second receiver 9 respectively receive a first polarized light O1 (e.g., P-polarized light) and a second polarized light O2 (e.g., S-polarized light) from the optical path deflection projector.

[0117] A polarizer is disposed at the front end of each receiver (before the photosensitive path). For example, a first polarizer 81 is disposed at the front end of the first receiver 8, and a second polarizer 91 is disposed at the front end of the second receiver 9, see [reference needed]. Figure 10 The polarization direction of the first polarizer 81 is designed to be consistent with the polarization direction of the first polarized light 01, while the polarization direction of the second polarizer 91 is designed to be consistent with the polarization direction of the second polarized light 02.

[0118] Each receiver also contains an infrared chip, which is located between the polarizer and the photosensitive element. For example, the first infrared chip 83 in the first receiver 8 is located between the first polarizer 81 and the first photosensitive element 82, and the second infrared chip 93 in the second receiver 9 is located between the second polarizer 91 and the second photosensitive element 92. See [reference needed]. Figure 10 .

[0119] The optical path deflector provided in this application emits light with two different polarization directions: first polarized light 01 and second polarized light 02, both of which are projected onto the surface of a target object. In the light reflected by the target object, the first polarized light 01 passes through the first polarizer 81 and is received by the first infrared chip 83. Similarly, the second polarized light 02 passes through the second polarizer 91 and is received by the second infrared chip 93. In this way, stray light with inconsistent polarization directions cannot pass through the polarizer, thus reducing the problem of stray light interfering with the calculation of depth imaging.

[0120] Since the optical path deflector projector can emit polarized light with two polarization directions, this example sets up two receivers to receive the reflected light with the two polarization directions respectively.

[0121] See some examples in this application. Figure 11 To the end Figure 13 The receiving end includes a third receiver 10 and a switchable filter module; the third receiver 10 includes a third photosensitive element g and a fourth photosensitive element h, the third photosensitive element g is used to receive the first polarized light O1, and the fourth photosensitive element h is used to receive the second polarized light O2; the switchable filter module is configured to selectively place a first polarizer c, a second polarizer d, or an optically transparent element e before the photosensitive path of the third receiver 10; wherein the polarization direction of the first polarizer c is the same as the polarization direction of the first polarized light O1, the polarization direction of the second polarizer d is the same as the polarization direction of the second polarized light O2, and the optically transparent element e allows all polarized light to pass through.

[0122] See Figures 11 to 13The example in this application provides a second design scheme for the receiver, which realizes flexible switching of multiple working modes through a combination of a receiver, namely the third receiver 10, and a switchable filter module.

[0123] In this example of the application, the core element is mechanical switching. Users can selectively move different optical elements, such as the first polarizer c, the second polarizer d, or the optically transparent element e, into the optical path according to instructions, specifically placing them in front of the third receiver 10 (i.e., in front of the photosensitive path), thereby enabling a single receiver to acquire P-polarized light images, S-polarized light images, or mixed light images in a time-division multiplexing manner. This design achieves functional versatility with relatively low hardware costs.

[0124] See some examples in this application. Figures 11 to 13 The third receiver 10 further includes a polarization beam splitter f, which is configured to transmit the first polarized light O1 and reflect the second polarized light O2; the third photosensitive element g is disposed in the transmission path of the polarization beam splitter f; and the fourth photosensitive element h is disposed in the reflection path of the polarization beam splitter f.

[0125] In this example of the application, the core element is optical beam splitting. A polarization beam splitter f is integrated within the third receiver 10. This polarization beam splitter f can separate the incident light according to its polarization state: transmitting the first polarized light O1 (P-polarized light) to the third photosensitive element g (P-type photosensitive chip), and reflecting the second polarized light O2 (S-polarized light) to the fourth photosensitive element h (S-type photosensitive chip). This allows the system to simultaneously capture two polarized light images without switching, avoiding mechanical movement and improving reliability and imaging speed.

[0126] In summary, this example provides two implementation paths: one is to achieve low-cost multi-mode detection through external mechanical switching, and the other is to achieve high-efficiency synchronous dual-path imaging through internal optical beam splitting in the receiver. Both of these approaches embody the design of achieving polarization resolution using a single receiver.

[0127] The second scheme of the receiver provided in this application uses only one receiver (i.e., the third receiver 10) to receive two different polarization patterns. Different optical elements are mechanically switched using a switcher, which has three structures: a first polarizer c, a second polarizer d, or an optically transparent element e.

[0128] See Figure 11When the first light-emitting area 101 (e.g., a P-type polarized light source) in the optical path deflection projector is lit, the filter module at the front end of the third receiver 10 of the receiving end switches to the first polarizer c (e.g., a P-type polarizer) to allow the first polarized light O1 (e.g., P-polarized light) to pass through. The first polarized light O1 can completely pass through the polarization beam splitter f to reach the third photosensitive chip g and thus form an image.

[0129] See Figure 12 When the second light-emitting area 102 (e.g., an S-polarized light source) in the optical path deflection projector is lit, the filter module at the front end of the third receiver 10 of the receiving end switches to the second polarizer d (e.g., an S-polarized polarizer) to allow the second polarized light 02 (e.g., S-polarized light) to pass through. The second polarized light 02 is then reflected at 45° to the fourth photosensitive chip h for imaging.

[0130] See Figure 13 When the first light-emitting area 101 and the second light-emitting area 102 (two polarized light sources) in the optical path deflection projector are lit simultaneously, the filter module at the front end of the third receiver 10 of the receiving end switches to the optical transparent element e so that the two polarized lights can be imaged separately.

[0131] It should be noted that the polarization beam splitting element f polarization beam splitting prism is composed of two right-angled triangular prisms bonded together, and the bonding surface of the two right-angled triangular prisms is provided with a beam splitting film, such as a semi-transparent and semi-reflective film.

[0132] See some examples in this application. Figure 14 The receiving end includes a fourth receiver 11, which includes a fifth photosensitive element 1101, and the fifth photosensitive element 1101 is a polarization image sensor. Multiple photosensitive pixels of the polarization image sensor integrate micro-polarization filters in different directions, including at least a first type of pixel sensitive to the first polarized light O1 and a second type of pixel sensitive to the second polarized light O2, so as to simultaneously acquire and distinguish image information of the first polarized light O1 and the second polarized light O2.

[0133] In this example of the application, see Figure 14 The receiving end employs a fourth receiver 11. The core of this fourth receiver 11 is an integrated polarization image sensor as its fifth photosensitive element 1101. The key to this solution lies in directly integrating polarization filtering functionality at the sensor pixel level.

[0134] The example provided in this application presents a third optical design scheme for the receiver, which also adopts a single receiver configuration. Its core lies in using a dedicated polarization image sensor (or polarization sensing chip) to simultaneously receive and resolve two different polarization light patterns.

[0135] The key to this example lies in the special design at the photosensitive element level: on its imaging focal plane, multiple adjacent physical pixels are integrated into a functional "superpixel" through a micro-polarization filter array. Each superpixel contains at least two micro-polarization filters with different transmission axis directions. Combining the characteristics of the optical path deflection projector in this application emitting first polarized light O1 (e.g., P-polarized light, 0°) and second polarized light O2 (e.g., S-polarized light, 90°), the polarization image sensor specifically integrates filters corresponding to these two polarization directions. That is, the first type of pixel is mainly sensitive to P-polarized light in the 0° direction, and the second type of pixel is mainly sensitive to S-polarized light in the 90° direction.

[0136] This design allows a single photosensitive element to simultaneously acquire image information carried by P-polarized and S-polarized light within a single exposure time, without requiring any external moving parts or polarization beam splitters. The individual, aligned polarization images are then reconstructed using an interpolation algorithm. This approach significantly improves the system's integration, reliability, and image acquisition efficiency.

[0137] According to another embodiment of this application, a robotic vacuum cleaner is provided, which includes the three-dimensional sensing system described above.

[0138] The specific implementation methods of the three-dimensional sensing method and the sweeping robot in this application can refer to the various embodiments of the three-dimensional sensing system described above. Therefore, they have at least all the beneficial effects brought about by the technical solutions of the above embodiments, and will not be described in detail here.

[0139] The above embodiments mainly describe the differences between the various embodiments. As long as the different optimization features between the various embodiments are not contradictory, they can be combined to form a better embodiment. For the sake of brevity, they will not be elaborated here.

[0140] While specific embodiments of this application have been described in detail by way of examples, those skilled in the art should understand that the above examples are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of this application. The scope of this application is defined by the appended claims.

Claims

1. A three-dimensional sensing system, characterized in that, Including a light path deflection projector, which includes: The light source module (1) includes a first light-emitting area (101) and a second light-emitting area (102). The first light-emitting area (101) is used to emit first polarized light (01), and the second light-emitting area (102) is used to emit second polarized light (02). A polarizing beam splitter (6) is disposed on the transmission path of the light emitted by the light source module (1) to split the incident light according to the polarization state, wherein the first polarized light (01) is transmitted to form a first optical path and the second polarized light (02) is reflected to form a second optical path. A reflector (2) is disposed on the second optical path to reflect the second polarized light (02) reflected by the polarizing beam splitter (6) toward the first direction; The first collimating element (3) is disposed on the first optical path and is used to collimate the first polarized light (01) transmitted through the polarizing beam splitter (6); A second collimating element (4) is disposed in the first direction for collimating the second polarized light (02) reflected by the mirror (2); and, A diffractive optical element is placed in the collimated optical path to diffract the collimated beam into a structured light pattern; In this process, by selectively illuminating the first light-emitting area (101) and / or the second light-emitting area (102), the optical path deflection projector can project structured light patterns with the same or different characteristic parameters, including the field of view (FOV) and / or speckle density.

2. The three-dimensional sensing system according to claim 1, characterized in that, The polarization directions of the first polarized light (01) and the second polarized light (02) are orthogonal to each other; Wherein, the first polarized light (01) is P-polarized light, and the second polarized light (02) is S-polarized light.

3. The three-dimensional sensing system according to claim 1, characterized in that, The first light-emitting area (101) and the second light-emitting area (102) are arranged side by side or staggered on the light source module (1), and the first light-emitting area (101) and the second light-emitting area (102) can be controlled independently.

4. The three-dimensional sensing system according to claim 1, characterized in that, The diffractive optical element is configured as one, which is capable of receiving light rays collimated by the first collimating element (3) and the second collimating element (4); The minimum transverse period Ph and minimum vertical period Pv of the diffractive optical element satisfy the following relationship: Ph=λ / 2sin(arctan(L1 / (2*f3))); Pv=λ / 2sin(arctan(H1 / (2*f3))); Wherein, λ is the wavelength of the light emitted by the light source module (1), L1 and H1 are the length and width of the light emission size of the first light emission area (101) respectively, and f3 is the focal length of the first collimating element (3).

5. The three-dimensional sensing system according to claim 4, characterized in that, The length L2 and width H2 of the second light-emitting area (102) satisfy the following relationship: L2=2*f4*tan(arcsin(λ / 2*Ph)); H2=2*f4*tan(arcsin(λ / 2*Pv)); Where f4 is the focal length of the second collimating element (4).

6. The three-dimensional sensing system according to claim 4 or 5, characterized in that, The first light-emitting region (101) includes a plurality of first light-emitting units (a) arranged in a first array for emitting the first polarized light (01). The second light-emitting region (102) includes a plurality of second light-emitting units (b) arranged in a second array for emitting the second polarized light (02). The first array and the second array are arranged alternately, such that when the first light-emitting area (101) and the second light-emitting area (102) are lit at the same time, the speckle spots originating from the first light-emitting unit (a) and the speckle spots originating from the second light-emitting unit (b) projected by the diffractive optical element do not overlap in space.

7. The three-dimensional sensing system according to claim 6, characterized in that, The arrangement pitch of the second light-emitting unit (b) in the second light-emitting area (102) satisfies the following relationship: pitch=2*f4*tan(arctan(B / (2*Z)), where z is the preset projection distance, f4 is the focal length of the second collimating element (4), and B is the spacing between the speckle lines generated by the second light-emitting area (102).

8. The three-dimensional sensing system according to any one of claims 1-3, characterized in that, The diffractive optical element consists of two components, including a first diffractive optical element (7) and a second diffractive optical element (5). The first diffractive optical element (7) is located on the light-emitting path of the first collimating element (3), and the second diffractive optical element (5) is located on the light-emitting path of the second collimating element (4). The microstructure period of the first diffractive optical element (7) is different from that of the second diffractive optical element (5), so that the structured light patterns projected when the first light-emitting area (101) and the second light-emitting area (102) are lit respectively have different field of view (FOV).

9. The three-dimensional sensing system according to claim 8, characterized in that, The minimum transverse period Ph7 and minimum vertical period Pv7 of the first diffractive optical element (7) satisfy the following relationship: Ph7=λ / 2sin(arctan(L1 / (2*f3))); Pv7=λ / 2sin(arctan(H1 / (2*f3))); Wherein, λ is the wavelength of the light emitted by the light source module (1), L1 and H1 are the length and width of the light emission size of the first light emission area (101) respectively, and f3 is the focal length of the first collimating element (3).

10. The three-dimensional sensing system according to claim 8, characterized in that, The minimum transverse period Ph5 and minimum vertical period Pv5 of the second diffractive optical element (5) satisfy the following relationship: Ph5=λ / 2sin(arctan(L2 / (2*f4))); Pv5=λ / 2sin(arctan(H2 / (2*f4))); Wherein, λ is the wavelength of the light emitted by the light source module (1), L2 and H2 are the length and width of the light emission size of the second light emission area (102) respectively, and f4 is the focal length of the second collimating element (4).

11. The three-dimensional sensing system according to claim 1, characterized in that, The three-dimensional sensing system further includes a receiver, which includes at least one photosensitive element configured to receive light reflected from a target object carrying the structured light pattern for imaging the first polarized light (01) originating from the first light-emitting area (101) and the second polarized light (02) originating from the second light-emitting area (102).

12. The three-dimensional sensing system according to claim 11, characterized in that, The receiving end includes a first receiver (8) and a second receiver (9); The first receiver (8) is provided with a first photosensitive element (82) inside, and a first polarizer (81) is provided in front of the photosensitive path of the first receiver (8), and the polarization direction of the first polarizer (81) is the same as the polarization direction of the first polarized light (01). The second receiver (9) is provided with a second photosensitive element (92) inside, and a second polarizer (91) is provided in front of the photosensitive path of the second receiver (9), and the polarization direction of the second polarizer (91) is the same as the polarization direction of the second polarized light (02); The first photosensitive element (82) is used to receive the first polarized light (01), and the second photosensitive element (92) is used to receive the second polarized light (02).

13. The three-dimensional sensing system according to claim 11, characterized in that, The receiving end includes a third receiver (10) and a switchable filter module; The third receiver (10) includes a third photosensitive element (g) and a fourth photosensitive element (h), the third photosensitive element (g) being used to receive the first polarized light (01), and the fourth photosensitive element (h) being used to receive the second polarized light (02). The switchable filter module is configured to selectively place a first polarizer (c), a second polarizer (d), or an optically transparent element (e) in front of the photosensitive path of the third receiver (10); wherein the polarization direction of the first polarizer (c) is the same as the polarization direction of the first polarized light (01), the polarization direction of the second polarizer (d) is the same as the polarization direction of the second polarized light (02), and the optically transparent element (e) allows all polarized light to pass through.

14. The three-dimensional sensing system according to claim 13, characterized in that, The third receiver (10) further includes a polarization beam splitter (f), which is configured to transmit the first polarized light (01) and reflect the second polarized light (02). The third photosensitive element (g) is disposed on the transmission light path of the polarization beam splitter (f); The fourth photosensitive element (h) is disposed on the reflected light path of the polarization beam splitter (f).

15. The three-dimensional sensing system according to claim 11, characterized in that, The receiving end includes a fourth receiver (11), the fourth receiver (11) includes a fifth photosensitive element (1101), and the fifth photosensitive element (1101) is a polarization image sensor; The polarization image sensor integrates micro-polarization filters of different directions on multiple photosensitive pixels, including at least a first type of pixel sensitive to the first polarized light (01) and a second type of pixel sensitive to the second polarized light (02), so as to be able to simultaneously acquire and distinguish image information of the first polarized light (01) and the second polarized light (02).

16. A sweeping robot, characterized in that, include: The three-dimensional sensing system according to any one of claims 1-15.

Images