WO2023077864A1

WO2023077864A1 - Variable field of view scanning system and method therefor

Info

Publication number: WO2023077864A1
Application number: PCT/CN2022/106338
Authority: WO
Inventors: 陈宇宸; 潘超; 赵晗
Original assignee: 华为技术有限公司
Priority date: 2021-11-05
Filing date: 2022-07-18
Publication date: 2023-05-11
Also published as: CN116087985A

Abstract

A variable field of view scanning system (100) and a method therefor. The variable field of view scanning system (100) comprises: a multi-curved rotary prism (10), which at least has a first curved reflective surface (1) and a second curved reflective surface (2), the first curved reflective surface (1) being designed for a first field of view, the second curved reflective surface (2) being designed for a second field of view, and at least one among the field of view orientation and the field of view angle range of the first field of view being different from that of the second field of view; and a light detector (50), which is adapted to receive first light reflected from the first curved reflective surface (1) so as to generate a first image corresponding to the first field of view, and to receive second light reflected from the second curved reflective surface (2) so as to generate a second image corresponding to the second field of view. By using the variable field of view scanning system (100), imaging or detection functions of different fields of view may be implemented. The variable field of view scanning system (100) may be widely used in navigation fields, such as automatic vehicle driving, unmanned aerial vehicles and robots.

Description

Variable field of view scanning system and method thereof

This application claims priority to a Chinese patent application filed with the State Intellectual Property Office of China on November 5, 2021, application number 202111308478.7, application title "Variable Field of View Scanning System and Method", the entire contents of which are incorporated by reference In this application.

technical field

The present application relates to the field of optical detection, in particular to a variable field of view scanning system and method thereof. More particularly, the variable field of view scanning system and method thereof can be applied to radar systems such as vehicle automatic driving, field of view automatic detection, and the like.

Background technique

As a device that uses laser light to measure the distance, position, attitude and other information of the target, it mainly includes the triangulation ranging method and the time-of-flight method. The time-of-flight method is to transmit the laser signal to the target and receive the target object. After the reflected echo signal, the distance between the lidar and the target is calculated by the time difference between the transmitted and received light.

For different application scenarios, lidars with different performance parameters are required. Some scenarios require a large detection range, and some scenarios require a large field of view, especially for autonomous driving, which may require switching between different fields of view.

Contents of the invention

The purpose of the present disclosure is to provide a variable field of view scanning system, which can rapidly realize imaging and detection of objects in different desired fields of view.

According to a first aspect of the present disclosure, a variable field of view scanning system is provided. The variable field of view scanning system includes: a multi-curved rotating prism having at least a first reflective curved surface and a second reflective curved surface, wherein the first reflective curved surface is designed for the first field of view, and the second reflective curved surface is designed for a second field of view, at least one of a field orientation and a field angle range of said first field of view being different from said second field of view; a photodetector adapted to receive reflections from said first field of view first light reflected by the curved surface to generate a first image corresponding to the first field of view, and receiving second light reflected from the second reflective curved surface to generate a second image corresponding to the second field of view image.

Through the variable field of view scanning system of the present disclosure, it can perform fast imaging and detection for different fields of view with a simple structure. This imaging or detection function of different fields of view can be widely used in navigation fields such as vehicle autonomous driving, robots, drones, and the like.

In some embodiments, the difference between the minimum lateral imaging resolution of the first image and the second image is within ±10% of the minimum lateral imaging resolution of said first image. In this manner, the first image and the second image generated by the variable field of view scanning system may generally have substantially the same imaging resolution, thereby facilitating viewing by the user.

In some embodiments, the furthest imaging distance in the first field of view corresponding to the first image is different from the furthest imaging distance in the second field of view corresponding to the second image. In this way, different maximum imaging distances can be matched for different fields of view, whereby objects at different distances can be imaged more widely throughout the entire field of view.

In some embodiments, the multi-curved prism has a plurality of reflective curved surfaces greater than 2, including a first reflective curved surface and a second reflective curved surface, and the plurality of reflective curved surfaces are designed for a plurality of different reflective surfaces. field of view. In these embodiments, the coverage of different fields of view may be wider.

In some embodiments, the entire field of view formed by the plurality of fields of view has an axis of symmetry, the first field of view and the second field of view are located on the same side of the axis of symmetry, and the second field of view The field of view is closer to the axis of symmetry than the first field of view, but has a smaller range of field angles and/or a farther maximum imaging distance. In some other embodiments, the multi-curved rotating prism further includes a third reflective curved surface, the third reflective curved surface is designed for a third field of view, and the photodetector is further configured to receive light from the third reflecting the third light reflected by the curved surface to generate a third image corresponding to the third field of view, wherein the first field of view, the second field of view and the third field of view are located at the axis of symmetry On the same side, the angle ranges of the first, second, and third fields of view decrease sequentially, but the corresponding furthest imaging distances increase sequentially. In this way, it may be beneficial for field of view detection such as vehicle autonomous driving, which generally requires a large field of view for close range detection and a small field of view for long distance detection, while long distances usually require A higher transmit laser power is required, and a reduced field of view angular range also helps reduce the laser's power budget.

In some embodiments, the multi-curved prism further includes a fourth reflective curved surface, the fourth reflective curved surface is designed for a fourth field of view, and the fourth field of view is related to the first field of view with respect to the Symmetry Axisymmetric. In this way, a field of view may be provided which is at least partially symmetric about an axis of symmetry, which may be advantageous for field of view detection such as for autonomous driving of a vehicle.

In some embodiments, the furthest imaging distance corresponding to the first image is in the range of 20m-30m, the furthest imaging distance corresponding to the second image is in the range of 60m-75m, and the third image corresponds to The farthest imaging distance is in the range of 180m-220m. Using these designed numerical ranges can meet the field of view detection requirements such as vehicle automatic driving.

In some embodiments, the light detector is configured to receive the first light during a first time period and generate the first image, and to receive the second light during the second time period , and generate the second image, the first time period is different from the second time period. In these embodiments, this means that it is possible to use a single photodetector to detect the image.

In some embodiments, during a transition period from said first time period to said second time period, said multi-curved rotating prism is operable to rotate to adjust the orientation of said multi-curved rotating prism, However, during the first time period and the second time period, the multi-curved rotating prism remains stationary. This means that the field of view detection of the present disclosure is performed by emitting a detection beam having a two-dimensional cross-section to a predetermined target area.

In some embodiments, the system may further include: a laser for emitting a probe beam to the multi-curved rotating prism; and a beam splitter arranged between the laser and the multi-curved rotating prism for transmitting passing the probe beam emitted from the laser and reflecting the light from the multi-curved rotating prism to the photodetector. In this way, the arrangement of the beam splitter allows the light path incident to the multi-curved rotating prism and the light path reflected from the multi-curved rotating prism back to the photodetector to partially overlap, which can make the overall variable field of view scanning system of the present disclosure The size is more compact.

In some embodiments, the system may further include: a laser for emitting detection light; a micro-electromechanical scanning mirror (MEMS) for receiving the detection light emitted from the laser and scanning the detection light projected to a predetermined target area in a manner, wherein the multi-curved rotating prism is configured to adjust the orientation of the corresponding reflective curved surface according to the scanned predetermined target area, so as to receive light from the predetermined target area, and the predetermined target area The light is reflected to the photodetector. In these embodiments, alternative arrangements of the light sources of the variable field of view scanning system are provided.

According to a second aspect of the present disclosure, a radar system is provided, which includes the variable field of view scanning system according to the first aspect.

According to a third aspect of the present disclosure, there is provided a terminal device, which includes the radar system according to the second aspect.

In some embodiments, the terminal device includes at least one of a vehicle, a drone, and a robot.

According to a fourth aspect of the present disclosure, a variable field of view scanning method based on a multi-curved rotating prism is provided. The method includes: reflecting first light from a first field of view through a first reflective curved surface of the multi-curved prism, wherein the first curved reflective surface is designed for the first field of view; receiving the light with a light detector first light to generate a first image corresponding to the first field of view; second light from a second field of view is reflected by a second reflective curved surface of the multi-curved rotational prism, wherein the second reflective curved surface is configured for a second field of view, wherein at least one of a field orientation and a field angle range of the first field of view differs from the second field of view; and receiving the second field of view with the photodetector light to generate a second image corresponding to the second field of view.

In some embodiments, reflecting the first light from the first field of view through the first reflective curved surface of the multi-curved prism comprises: holding the multi-curved prism stationary for a first period of time to reflect light from the first field of view. the first light of the first field of view; and reflecting the second light from the second field of view by the second reflective curved surface of the multi-curved rotating prism comprises: keeping the multi-curved rotating prism stationary for a second period of time , to reflect a second light from the second field of view; wherein the second time period is different from the second time period.

In some embodiments, the difference between the minimum lateral imaging resolution of the first image and the second image is within ±10% of the minimum lateral imaging resolution of the first image.

In some embodiments, the furthest imaging distance in the first field of view corresponding to the first image is different from the furthest imaging distance in the second field of view corresponding to the second image.

In some embodiments, the multi-curved prism has a plurality of reflective curved surfaces greater than 2, including a first reflective curved surface and a second reflective curved surface, and the plurality of reflective curved surfaces are designed for different multiple viewing angles. field, the entire field of view formed by the plurality of viewing fields has a symmetry axis, and the method further includes: controlling the rotation of the multi-curved rotating prism so that the plurality of reflective curved surfaces face the plurality of viewing fields The reflection of the light is carried out sequentially and cyclically.

In some embodiments, the first field of view and the second field of view are located on the same side of the axis of symmetry, and the second field of view is closer to the axis of symmetry than the first field of view, but It has a smaller field of view angle range and a farther corresponding maximum imaging distance.

In some embodiments, the multi-curved prism further includes a third reflective curved surface, the third reflective curved surface is designed for a third field of view, and the photodetector is further configured to receive reflections from the third third light reflected by a curved surface to generate a third image corresponding to the third field of view, wherein the first field of view, the second field of view and the third field of view are located at the same axis of symmetry On the side, the angle ranges of the first, second, and third fields of view decrease sequentially, but the corresponding furthest imaging distances increase sequentially.

In some embodiments, the furthest imaging distance corresponding to the first image is in the range of 20m-30m; the furthest imaging distance corresponding to the second image is in the range of 60m-75m; the third image corresponds to The farthest imaging distance is in the range of 180m-220m.

In some embodiments, the method further includes: using a laser to emit a detection beam; causing the reflective curved surface of the multi-curved rotating prism to reflect the detection beam to the target area; and using a beam splitter to transmit the detection beam emitted from the laser, And reflect the light from the multi-curved rotating prism to the light detector.

In some embodiments, the method further includes: using a laser to emit a detection beam; using a microelectromechanical scanning mirror (MEMS) to receive the detection light beam emitted from the laser, and project the detection light in a scanning manner to the target area.

It should also be understood that what is described in the Summary of the Invention is not intended to limit the key or important features of the embodiments of the present disclosure, nor is it intended to limit the scope of the present disclosure. Other features of the embodiments of the present disclosure will be easily understood through the following description.

Description of drawings

FIG. 1 shows a schematic structural diagram of a variable scanning system according to a first exemplary embodiment of the present disclosure;

Fig. 2 shows a schematic structural diagram of a variable scanning system according to a second exemplary embodiment of the present disclosure;

FIG. 3 shows a schematic structural diagram of a variable scanning system according to a second exemplary embodiment of the present disclosure; and

FIG. 4 shows a flowchart of a variable field of view scanning method according to an example embodiment of the present disclosure.

Detailed ways

Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present disclosure are shown in the drawings, it should be understood that the disclosure may be embodied in various forms and should not be construed as limited to the embodiments set forth herein; A more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are for exemplary purposes only, and are not intended to limit the protection scope of the present disclosure.

The purpose of the present disclosure is to provide an improved variable field of view scanning system, which can provide variable field of view scanning with a simple and efficient structure. To this end, the idea of the present disclosure is to construct an operable rotating multi-curved prism, wherein the multi-curved prism has at least a first reflective curved surface and a second reflective curved surface, and the first reflective curved surface is designed for the first viewing angle. The second reflective curved surface is designed for a second field of view, and at least one of field orientation and field angle range of the first field of view is different from that of the second field of view. In addition, the system is also configured with a light detector to detect images corresponding to the above-mentioned first field of view and the second field of view. Through the above configuration, with the rotation of the multi-curved rotating prism, different reflective curved surfaces on the multi-curved rotating prism can be used to project light to different viewing fields and/or receive light from different viewing fields, thereby realizing different viewing fields. Imaging and/or distance detection.

In order to better understand the concept of the present disclosure, FIG. 1 shows a schematic structural diagram of a variable scanning system according to a first exemplary embodiment of the present disclosure.

As shown in FIG. 1 , the variable scanning system 100 at least includes a laser 20 , a beam splitter 30 , a lens 40 , a multi-curved rotating prism 10 , a light detector 50 and a controller (not shown).

The laser 20 is configured to emit a pulsed probe beam of a predetermined wavelength, and project the probe beam onto the reflective curved surface of the multi-curved rotary prism 10 . In some embodiments, the emission power of the laser 21 is also adjustable. In some embodiments, the laser can be a single light source. In still other embodiments, the laser may be a light source array composed of a plurality of light sources. As a non-limiting example, the laser may be a light source such as an edge emitting laser (EEL) or a vertical cavity surface emitting laser (VCSEL). The aforementioned predetermined wavelength may be any suitable wavelength, including but not limited to wavelengths of visible light, infrared light, or ultraviolet light.

A lens 40 may be disposed between the laser 20 and the multi-curved rotating prism 10 to shape (eg, collimate or diverge) the beam emitted by the laser 20 . As an example, lens 40 may be a diverging lens to shape the collimated beam emitted by laser 20 into a diverging beam having a predetermined cross-sectional dimension. The aforementioned predetermined cross-sectional size may match the size of the reflective curved surface of the multi-curved rotating prism 10 to be incident. That is, the lens 40 may allow the probing beam to be projected onto the reflective curved surface of the polycurved rotational prism 10 in a two-dimensional cross-section. In some embodiments, lens 40 may be presented as a single lens or as a lens assembly. In yet other embodiments, the lens 40 is movable, so that the cross-sectional shape and/or size of the probe beam to be emitted can be adjusted as required.

The multi-curved rotating prism 10 may be a rotating prism having a plurality of reflective curved surfaces, which is configured to be operatively rotated to project the detection beam incident on its corresponding reflecting surface to a predetermined target area, and to direct the reflected light from the target area Reflected back to photodetector 50 .

As an example only, the multi-curved rotating prism 10 of FIG. and the sixth reflective surface 6 . However, it will be appreciated that in other embodiments, the multi-curved rotational prism 10 may have more or fewer even or odd numbers of reflective surfaces, for example, 2, 3, 4, 5, 7, 8, 9, and 10 reflective surfaces.

In some embodiments, the above-mentioned plurality of reflective curved surfaces may be respectively designed for different fields of view.

Here, as used herein, the term "different field of view" means at least one of the orientation of the field of view and the range of angle of view between the two or more fields of view corresponding to the two or more reflective curved surfaces. are different from each other. The term "field angle range" is defined as the included angle formed by the boundary rays of the light beam reflected by the reflective curved surface in a predetermined plane. Generally speaking, the field of view angle range corresponds to the curvature of the reflective surface one-to-one. Therefore, "different viewing angle ranges" may mean that the curvature designs corresponding to two or more reflective curved surfaces are different from each other. The term "field of view orientation" is defined as the direction to which the bisector of the included angle of the boundary rays of the light beam reflected by the reflective curved surface in a predetermined plane points. As a non-limiting example, the aforementioned predetermined plane may be, for example, a plane where the optical axis of the detection beam reflected by the reflective curved surface and the scanning direction of the region are located.

As an example, as shown in Figure 1, the first reflective curved surface 1 of the multi-curved prism 10 is designed for the first field of view, the second reflective curved surface 2 is designed for the second visual field, and the third reflective curved surface 3 is designed For the third field of view, the fourth curved reflective surface 4 can be designed for the fourth field of view, the fifth curved reflective surface 5 can be designed for the fifth field of view, and the sixth curved reflective surface 6 can be designed for the sixth field of view , wherein at least one of field orientations and field angle ranges of the first, second, third, fourth, fifth, and sixth fields of view are different from each other.

The first to sixth fields of view corresponding to the above-mentioned first to sixth reflective curved surfaces 1-6 may have different field orientations and different or the same field angle ranges. For example, as shown in FIG. 1 , the angle ranges corresponding to the first to sixth fields of view are different or the same, for example, 40 degrees, 15 degrees, 5 degrees, 5 degrees, 15 degrees and 40 degrees respectively. In particular, the fields of view of the first reflective curved surface 1 and the sixth reflective curved surface 6 may have different viewing field orientations, but the same viewing angle range, such as 40 degrees; the second reflective curved surface 2 and the fifth reflective curved surface Can have different viewing field orientations, but the same viewing field angle range, such as 15 degrees; and the third reflective curved surface 3 and the fourth reflective curved surface can have different viewing field orientations, but the same viewing field angle range, such as 5 degrees .

Furthermore, the whole of the multiple viewing fields corresponding to the multiple reflecting curved surfaces of the above-mentioned multi-curved rotating prism 10 may constitute a full viewing field corresponding to the multi-curved rotating prism 10 . In some embodiments, the full field of view may have an axis of symmetry. In particular, with respect to the axis of symmetry, the closer the field of view is to the axis of symmetry, the smaller the angular range of the field of view it has.

For example, as shown in FIG. 1 , the entirety of the first, second, third, fourth, fifth, and sixth fields of view may constitute the full field of view of the multi-curved rotating prism 10 . The full field of view may have an axis of symmetry X. In particular, the first, second, and third fields of view are located on one side of the symmetry axis X; the fourth, fifth, and sixth fields of view are located on the other side of the symmetry axis X; wherein the first, second, and third The field of view and the fourth, fifth, and sixth fields of view are respectively symmetrical about the symmetry axis X. Further, no matter which side of the symmetry axis X the field of view is on, it can be seen from FIG. 1 that the closer the field of view is to the axis of symmetry, the smaller the corresponding angle range of the field of view.

Although it has been emphatically described above that the plurality of reflective curved surfaces have correspondingly different fields of view, it can be understood that it is also possible that some of the above-mentioned plurality of reflective curved surfaces are designed to be used for completely identical fields of view. Depends on the needs of the design and/or application scenario.

In addition, although the description above focuses on a full field of view with an axis of symmetry, it can be understood that a full field of view without an axis of symmetry is also possible. For example, in other embodiments, it is conceivable that there is no full field of view corresponding to any one or more of the first, second, third, fourth, fifth, and sixth reflective curved surfaces, so that Asymmetric full field of view is easily obtained. Here, it is also easy to understand that a full field of view with an axis of symmetry X may be advantageous for certain application scenarios such as radar detection for autonomous vehicle driving, for example a full field of view with an axis of symmetry X may allow detection of vehicles directly in front and symmetrical fields of view on both sides. In some embodiments, the angle range of the above-mentioned full field of view may be in the range of 120 degrees to 180 degrees.

The light from the above-mentioned different fields of view (that is, echo signals from objects in the field of view) can enter the photodetector 50 through the reflective curved surface corresponding to the multi-curved rotating prism 10, and then the photodetector 50 Generate corresponding images.

For example, the light detector 50 is adapted to receive the first light reflected from the first reflective curved surface 1 to generate a first image corresponding to the first field of view; receive the second light reflected from the second reflective curved surface 2 to generate a corresponding The second image in the second field of view; ...; and so on, receiving the third light reflected from the nth reflective surface n to generate the nth image corresponding to the nth field of view, where n is an integer greater than 2 . As non-limiting examples, light detector 50 may be at least one of a time-of-flight (TOF) sensor, a single photon avalanche diode (SPAD) array, or a thermal imaging detector array.

It is easy to understand that the first image corresponding to the first field of view, the second image corresponding to the second field of view, and the nth image corresponding to the nth field of view may each have the longest imaging distance and Minimum lateral imaging resolution.

Here, the term "imaging distance" is defined as the distance from the variable scanning system to the object imaged by the photodetector of the variable field of view scanning system within the corresponding field of view. In particular, the term "the farthest imaging distance" is defined as the furthest distance from the object that can be imaged by the photodetector of the variable field of view scanning system in the corresponding field of view to the variable scanning system, and the furthest imaging distance may depend on Corresponding parameters such as the curvature of the reflecting surface, the emission power of the laser and/or the exposure time of the photodetector. Generally speaking, the smaller the curvature of the reflective surface, or the greater the emission power of the laser, or the longer the exposure time of the photodetector, the farther the farthest imaging distance can be in the corresponding field of view; The larger the curvature, the smaller the emission power of the laser, or the shorter the exposure time of the photodetector, the shorter the farthest imaging distance in the corresponding field of view. Therefore, the curvature of the reflective curved surface corresponding to the field of view, the emission power of the corresponding laser and/or the exposure time of the photodetector can be designed according to different requirements of the longest imaging distance of the corresponding field of view.

The term "transverse imaging resolution" is defined as the lateral length of the real object corresponding to a single pixel in the object image formed by the photodetector. The "transverse direction" here may refer to the direction in which the detection beam projected by the multi-curved rotating prism scans within the target area. In particular, the term "minimum lateral imaging resolution" is defined as the lateral length of the real object corresponding to a single pixel in the image of the object at the farthest imaging distance formed by the photodetector. It should be understood that the minimum lateral imaging resolution corresponds to the furthest imaging distance, which may reflect the clarity of objects at the furthest imaging distance. Generally speaking, as the imaged object in the field of view is closer to the variable field of view scanning system, its corresponding imaging distance is smaller, and its minimum lateral imaging resolution is correspondingly increased.

In some embodiments, different fields of view corresponding to different reflective curved surfaces on the multi-curved rotating prism 10 may be designed with corresponding different or the same maximum imaging distances in the variable scanning field of view system. In yet other embodiments, different fields of view may have different or the same minimum lateral imaging resolution, regardless of whether the longest imaging distances corresponding to the different fields of view are the same. As used herein and hereinafter, the term "same or substantially the same minimum lateral imaging resolution" or similar terms means that the minimum lateral resolutions differ from each other in the range of ±10%, ±5%, 3% or 1% Inside.

As an example only, as shown in FIG. 1 , the first, second, and third fields of view, or the third, fourth, and fifth fields of view may have different maximum imaging distances from each other; The sixth field of view, the second field of view and the fifth field of view, and the third field of view and the fourth field of view may have the same longest imaging distance among each other. In addition, regardless of whether the farthest imaging distances are the same or different, the minimum lateral imaging resolutions of the images corresponding to the above first to sixth fields of view may remain substantially the same.

For example, in the embodiment shown in Figure 1, the furthest imaging distance corresponding to the first field of view and the sixth field of view is in the range of 20m-30m; the furthest imaging distance corresponding to the second field of view and the fifth field of view is 60m In the range of -75m; and the farthest imaging distances corresponding to the third field of view and the fourth field of view are in the range of 180m-220m, but their minimum lateral imaging resolutions are basically the same. It should be understood that, according to application requirements, the farthest imaging distances corresponding to different fields of view can be designed, and the farthest imaging distances are not limited to the distances or distance ranges shown in FIG. 1 above. In this way, variable field-of-view scanning can be provided over a very wide range of distances while maintaining a substantially consistent minimum lateral imaging resolution.

Furthermore, in some embodiments, different maximum imaging distances may be combined with different field angle ranges. In particular, the smaller the field of view angle range, the longer the corresponding maximum imaging distance. Furthermore, in the example where the full field of view has a symmetry axis, the closer the field of view is to the symmetry axis, the smaller the corresponding angle range of the field of view and/or the longer the corresponding maximum imaging distance.

For example, in the example shown in FIG. 1, the first field of view, the second field of view and the third field of view may be located on the same side of the symmetry axis, wherein the angle ranges of the first, second, and third fields of view decrease sequentially , but the corresponding furthest imaging distance increases sequentially.

Matching design of the above-mentioned furthest imaging distance, field of view angle range and minimum lateral imaging resolution—especially as the furthest imaging distance increases, the field of view angle range decreases while still maintaining the same minimum lateral imaging resolution Design – may be beneficial for field of view scanning/distance detection such as vehicle autonomous driving, which typically requires a large field of view for close range detection and a small field of view for long distance detection, while Longer distances usually require higher transmit laser power, and reducing the field of view angle range also helps reduce the power budget of the laser.

In order to guide the beam (or echo signal) from the corresponding field of view and reflected by the corresponding reflective curved surface of the multi-curved rotating prism 10 to the photodetector 50, in some embodiments, the variable field of view scanning system 100 also A beam splitter 30 may be included, which may be positioned between the laser 20 and the polycurved rotational prism 10 (and more specifically, between the laser 20 and the lens 40) for transmitting probe light emitted from the laser, and reflecting Light from the multi-curved rotating prism is directed to the photodetector.

In a further embodiment, beam splitter 30 may be a reflector with a central hole. Thus, the beam splitter can allow the light emitted from the laser 20 to pass through the center hole of the reflector, while allowing the light from the multi-curved rotating prism to be reflected to the reflective area on the beam splitter except the center hole . With the help of the reflection of the reflection area, the above-mentioned reflected light from the multi-curved rotating prism can be reflected to the light detector 50 . It is easy to understand that the above-mentioned arrangement of the beam splitter allows the light path incident to the multi-curved rotating prism and the light path reflected from the multi-curved rotating prism back to the light detector to partially overlap. In this way, the overall size of the variable field of view scanning system of the present disclosure can be made more compact. Apparently, the above embodiments of the beam splitter are not limiting. In other embodiments, the beam splitter 30 is omitted, and instead arranged to have an optical path that does not overlap at all with the optical path incident from the laser 20 to the multi-curved rotating prism 10, so that the light reflected from the multi-curved rotating prism is directed back to the photodetector as well. possible.

A controller (not shown) may at least be coupled to the above-mentioned laser 20 , multi-curved rotating prism 10 and photodetector 50 for controlling these components. In particular, the emission power of the laser 20 can be controlled by, for example, a controller, so as to emit an illumination beam to an object at a predetermined farthest imaging distance within a predetermined field of view. In addition, the rotation of the multi-curved rotating prism 10 can be controlled by the controller, so that the predetermined reflection curved surface on the multi-curved rotating prism 10 (for example, the first, second, third, fourth, fifth or fifth in FIG. 1 six reflective surfaces) are oriented to allow the probe beam from the laser 20 (or, the divergent beam via the lens 40) to be incident on the predetermined reflective surface, and to allow light from a predetermined field of view to be reflected to the photodetector via the predetermined reflective surface 50 so that the photodetector 50 generates an image corresponding to a predetermined field of view. Here, it should be noted that the above-mentioned predetermined reflective curved surface (for example, the first, second, third, fourth, fifth or sixth reflective curved surface in FIG. 1 ) is oriented to allow detection from the laser 20 The multi-curved rotating prism 10 and thus the entire process of allowing light from a predetermined field of view to reflect to the photodetector 50 is incident on the predetermined reflective curved surface (or a diverging beam via the lens 40) Each of the reflective curved surfaces will remain stationary so that the aforementioned predetermined reflective curved surfaces (for example, the first, second, third, fourth, fifth, or sixth reflective curved surfaces in FIG. A probe beam is emitted for a predetermined field of view. Only when the detection and/or imaging of the predetermined field of view corresponding to the predetermined reflective curved surface by the optical detector 50 is completed, the multi-curved rotating prism 10 will be further rotated to orient the next predetermined reflective curved surface, so as to realize the next predetermined reflection The detection of the next predetermined field of view corresponding to the curved surface (that is, the multi-curved rotating prism 10 is further rotated so that the next predetermined reflective curved surface is oriented to allow the detection beam to be incident on the next predetermined The light in the field of view is reflected to the light detector 50 via the next predetermined reflective curved surface. In the embodiment of the present disclosure, the multi-curved rotating prism 10 is operable to rotate clockwise or counterclockwise, so as to sequentially detect the fields of view corresponding to the multiple reflective curved surfaces on the multi-curved rotating prism 10 and generate corresponding images . In some embodiments, these images may be presented to the user individually. In still other embodiments, these images can be stitched together and presented to the user.

For example, in the embodiment of FIG. 1, the multi-curved rotating prism 10 can be operated (for example, controlled by a controller) to rotate (counterclockwise or clockwise), so that the first reflective curved surface 1 is in a position facing the first field of view. position and remain stationary for a first period of time, and then the first curved reflective surface 1 can transmit the light emitted by the laser 10 and incident to the first curved reflective surface 1 via, for example, the beam splitter 30 and the lens 40 within the first period of time projected into the first field of view; at the same time, within the first time period, the first reflective curved surface 1 can receive light from the first field of view, and reflect the light to the photodetector 50 (for example, via the lens 40 and the beam splitter detector 30), from which the photodetector 50 can generate a first image. Once the detection of the first field of view is completed, the multi-curved rotating prism 10 may continue to rotate, for example, until the second reflective curved surface 2 is in a position facing the second field of view and remains stationary for a second period of time, and then the second reflective curved surface 2. The light emitted by the laser 10 and incident on the second reflective curved surface 2 via, for example, the beam splitter 30 and the lens 40 may be projected into the second field of view within the second time period; at the same time, during the second time period Inside, the second reflective curved surface 2 can receive light from the second field of view and reflect the light to the photodetector 50 (eg, via the lens 40 and the beam splitter 30), and the photodetector 50 can thereby generate a second images, where the second time period is different than the first time period. Similarly, the third field of view corresponding to the third reflective curved surface 3 may be followed in the third time period, the fourth field of view corresponding to the fourth reflective curved surface 4 in the fourth time period, and the The fifth field of view corresponding to the fifth reflective curved surface 5 and the sixth field of view corresponding to the sixth reflective surface 6 are detected in the sixth time period, and respective corresponding images are generated. By analogy, the field of view corresponding to more or less reflective curved surfaces may be detected (which may include distance detection of imaging objects within the field of view), and a corresponding image may be generated.

It is easy to understand that the above-mentioned first, second, third, fourth, fifth and sixth time periods are different from each other or do not overlap each other. In some embodiments, the later time period follows the previous time period, for example, the second time period immediately follows the first time period, the third time period immediately follows the second time period, and so on to other time periods. In this way, the individual fields of view can be scanned at maximum speed. In still some embodiments, it is also possible that there is a predetermined time interval between the latter time period and the previous time period, which depends on design requirements.

As the multi-curved rotating prism 10 continues to rotate, after detecting and imaging the last field of view, it can return to detecting and imaging the first field of view again. For example, in the embodiment of FIG. 1, after the sixth field of view is detected (which may include distance detection of imaging objects in the field of view) and imaging, as the multi-curved rotating prism 10 rotates, it can return to The first field of view is detected and imaged. That is to say, by using the rotation of the multi-curved rotating prism 10, the variable field of view scanning system can be between the first field of view, the second field of view, ..., and the last field of view (for example, the sixth field of view) Scanning detection and imaging are performed sequentially and cyclically.

Fig. 2 shows a schematic structural diagram of a variable scanning system according to a second exemplary embodiment of the present disclosure. The embodiment of FIG. 2 is similar to the embodiment of FIG. 1, but the difference is that in the embodiment of FIG. A target area is set; instead, the probe beam is projected to the preset target area through a micro-electro-mechanical scanning mirror (MEMS). Therefore, in the following introduction, in order to avoid redundant description, only the differences between the embodiment in FIG. 2 and the embodiment in FIG. 1 will be mainly introduced. For detailed descriptions of other components in FIG. 2 , reference may be made to the description of the embodiment in FIG. 1 .

Specifically, as shown in FIG. 2 , the variable scanning system 200 includes at least a laser 21 , a multi-curved rotating prism 10 , a photodetector 50 , a microelectromechanical scanning mirror (MEMS) 70 and a controller (not shown).

Similar to laser 20 in FIG. 1 , laser 21 in FIG. 2 may be configured to emit a pulsed probe beam of predetermined wavelength. In some embodiments, the emission power of the laser 21 is also adjustable. However, unlike the embodiment of FIG. 1 , the pulsed beam emitted by the laser 21 in FIG. 2 is directed to a micro-electromechanical scanning mirror (MEMS) 70 . In particular, in some embodiments, the probe beam emitted by laser 21 may be shaped (eg, collimated) before being directed to MEMS 70 .

The function of the MEMS 70 is to reflect the incident probe beam to the preset target area 60, and to scan the beam reflected by the MEMS 70 in different sub-areas within the target area 60 with a predetermined MEMS scanning field of view, wherein the term " A "predetermined MEMS scanning field of view" may be defined by both a predetermined scan angle range and a predetermined scan orientation, while the term "predetermined scan orientation" may be defined as the direction to which the angular bisector of the predetermined scan angle range actually scanned by the probe beam points.

It is easy to understand that the MEMS 70 can be scanned in different sub-regions within the target region 60 with different predetermined MEMS scanning fields of view, where the term "different predetermined MEMS scanning fields of view" means both the predetermined scanning angle range and the predetermined scanning orientation. At least one of them is different, and "different predetermined MEMS scanning fields of view" also means that the scanned sub-areas are different from each other. In some embodiments, different predetermined MEMS scanning fields of view can be designed such that the scanned sub-areas do not overlap each other. In some embodiments, the scanned sub-region depth (or, it can be referred to as the distance from the MEMS 70 or the variable scanning system) can depend on the emission power of the detection beam emitted by the laser 21, the greater the emission power of the detection beam , the deeper the scanned sub-region can be (ie, the farther the distance from the MEMS 7 or the variable scanning system).

In some embodiments, MEMS 70 can have a plurality of different predetermined MEMS scanning fields of view (or, MEMS scanned sub-regions), and they can be respectively designed with each reflective curved surface on the multi-curved rotating prism 10 for the field of view. Fields (see the description of the field of view for which each reflective curved prism 10 is designed in FIG. 1 ) correspond one-to-one. Thus, in response to the MEMS 70 scanning the target region 60 with the predetermined MEMS scanning field of view, the return of objects within the predetermined MEMS scanning field of view (or, corresponding to the field of view for which the reflective curved surface is designed) from the target region 60 The wave signal can be reflected to the photodetector 50 via the corresponding reflective curved surface on the multi-curved rotating prism 10 . Thus, the light detector 50 can generate an image corresponding to a predetermined MEMS scanning field of view of the target area 60 (or, corresponding to the field of view for which the reflective curved surface is designed).

As an example, as shown in FIG. 2 , the MEMS 70 can be sequentially scanned at different or the same predetermined scanning angle ranges such as 40 degrees, 15 degrees, 5 degrees, 5 degrees, 15 degrees, and 40 degrees, but defined by different predetermined scanning orientations. A predetermined MEMS scanning field of view is used to scan the target area 60 . As a response, the corresponding reflective curved surfaces on the multi-curved rotating prism 10 corresponding to, for example, 40 degrees, 15 degrees, 5 degrees, 5 degrees, 15 degrees, and 40 degrees of field of view angle ranges can be sequentially received from a predetermined MEMS scanning field of view. echo signals, and sequentially reflect the echo signals to the photodetector 50 via the corresponding reflective curved surface.

In some embodiments, the echo signal can be incident to the photodetector 50 through the lens 40 . It is easy to understand that providing the lens 40 facilitates focusing and imaging of an object at a predetermined distance (ie, the longest imaging distance) on the light detector 50 . In still other embodiments, the echo signal can be incident to the photodetector 50 via both the lens 40 and the reflector 31 . It is easy to understand that providing the reflector 31 can help the variable field of view scanning system to become compact.

Similar to the embodiment of FIG. 1 , in the embodiment of FIG. 2 , the corresponding field of view (or, corresponding predetermined MEMS scanning field of view) of the corresponding reflective curved surface on the multi-curved rotating prism 10 can have the same value as in the embodiment of FIG. 1 Similar or identical fields of view may have, for example, a symmetry axis, and the closer the field of view is to the symmetry axis, the smaller the corresponding angle range of the field of view.

In addition, the corresponding image of the corresponding field of view (or the corresponding predetermined MEMS scanning field of view) of the corresponding reflective curved surface on the multi-curved rotating prism 10 in the embodiment of FIG. resolution. Similarly, the farthest imaging distance here may depend on the curvature of the corresponding reflective curved surface, the emission power of the laser and/or the exposure time of the photodetector.

In some embodiments, different fields of view corresponding to different reflective curved prisms on the multi-curved prism 10 may have corresponding different or the same maximum imaging distances. In still other embodiments, different fields of view may have different or the same minimum lateral imaging resolution, regardless of whether the longest imaging distances corresponding to the different fields of view are the same. Furthermore, in some embodiments as well, different maximum imaging distances may be combined with different field angle ranges. In particular, the smaller the field of view angle range, the longer the corresponding maximum imaging distance. Furthermore, in the example where the full field of view has a symmetry axis, the closer the field of view is to the symmetry axis, the smaller the corresponding angle range of the field of view and/or the longer the corresponding maximum imaging distance.

A controller (not shown) may at least be coupled to the above-mentioned laser 21, MEMS 70, multi-curved rotating prism 10 and photodetector 50 for realizing the control of these components.

In particular, the emission power of the laser 21, and the predetermined scanning angle and predetermined scanning orientation of the MEMS 70 can be controlled by, for example, a controller, so as to realize sequential scanning of a plurality of predetermined MEMS scanning fields of view. At the same time, the rotation of the multi-curved rotating prism 10 can be controlled by the controller, so that the predetermined reflection curved surface on the multi-curved rotating prism 10 (for example, the first, second, third, fourth, fifth or the first in Fig. 2 Six reflective curved surfaces) are oriented to allow scanning from corresponding predetermined MEMS field of view (also corresponding to, for example, the field of view corresponding to the first, second, third, fourth, fifth, or sixth reflective curved surfaces in FIG. 2 ) is incident on the predetermined reflective curved surface, and is reflected to the photodetector 50 through the predetermined reflective curved surface, so that the photodetector 50 generates an image corresponding to the MEMS scanning field of view. Here, it needs to be particularly noted that, during the scanning process of each predetermined MEMS scanning field of view, the multi-curved rotating prism 10 and thus the various reflective curved surfaces thereon remain stationary, so that the photodetector 50 realizes the detection of Detection (here, may include distance detection of objects in the field of view) and imaging of the field of view corresponding to the predetermined reflective curved surface (that is, the predetermined MEMS scanning field of view). Only when the detection and/or imaging of the predetermined field of view corresponding to the predetermined reflective curved surface by the optical detector 50 is completed, the multi-curved rotating prism 10 will be further rotated to realize the next predetermined view corresponding to the next predetermined reflective curved surface. Detection of the field (i.e., further rotation of the multi-curved rotating prism 10 such that the next predetermined reflective curved surface is oriented to allow light from the field of view (or the next predetermined MEMS scanning field of view) corresponding to the next predetermined reflective curved surface to pass through the the next predetermined reflective curved surface and reflect to the light detector 50).

In the embodiment of FIG. 2 , the multi-curved rotating prism 10 is also operable to rotate clockwise or counterclockwise, so as to sequentially detect the fields of view corresponding to the plurality of reflective curved surfaces on the multi-curved rotating prism 10 and generate corresponding image. In some embodiments, these images may be presented to the user individually. In still other embodiments, these images can be stitched together and presented to the user.

For example, in the embodiment of FIG. 2, the multi-curved rotary prism 10 can be operated (for example, controlled by a controller) to rotate (counterclockwise or clockwise), so that the first reflective curved surface 1 is in a position facing the first field of view. position and remain stationary for a first period of time. During the first period of time, MEMS 70 is operable to scan the probe beam from laser 21 at the target area with a first predetermined MEMS scanning field of view having a first predetermined scanning angle range of, for example, 40 degrees, and then first reflect The curved surface 1 can reflect light of a corresponding first field of view (which corresponds to a predetermined MEMS scanning field of view and also has a field angle range of, for example, 40 degrees) to the light detector 50 (for example, via a lens) within a first time period. 40 and reflector 31), from which the light detector 50 can then generate a first image. Once the detection and/or imaging of the first field of view is completed, the multi-curved rotating prism 10 may continue to rotate, for example to such that the second reflective curved surface 2 is in a position facing the second field of view and remains stationary for a second time period. During the second time period, the MEMS 70 is operable to scan the probe beam from the laser 21 over the target area with a second predetermined MEMS scanning field of view having a second predetermined scanning angle range of, for example, 15 degrees, and then the second reflective curved surface 2 may reflect light of a corresponding second field of view (which corresponds to a predetermined MEMS scanning field of view, also having a field angle range of 15 degrees) to the light detector 50 (e.g., via lens 40 and reflector 31), from which the light detector 50 can generate a second image, wherein the second time period is different from the first time period.

Similar to the embodiment in FIG. 1 , the third field of view corresponding to the third reflective curved surface 3 may be followed in the third time period, the fourth field of view corresponding to the fourth reflective curved surface 4 in the fourth time period, and in the fourth time period. In the fifth time period, the fifth field of view corresponding to the fifth reflective curved surface 5 is detected, and in the sixth time period, the sixth field of view corresponding to the sixth reflective surface 6 is detected, and respective corresponding images are generated. By analogy, the field of view corresponding to more or less reflective curved surfaces can be detected and corresponding images can be generated.

Similar to the embodiment in FIG. 1 , the above-mentioned first, second, third, fourth, fifth time periods, and sixth time periods are different from each other or do not overlap each other. In some embodiments, the subsequent time period follows the previous time period, for example, the second time period immediately follows the first time period, the third time period immediately follows the second time period, and so on. In this way, the individual fields of view can be scanned at maximum speed. In still some embodiments, it is also possible that there is a predetermined time interval between the latter time period and the previous time period, which depends on design requirements.

As the multi-curved rotating prism 10 continues to rotate, after detecting and imaging the last field of view, it can return to detecting and imaging the first field of view. That is to say, by using the rotation of the multi-curved rotating prism 10 and the MEMS 70 to scan simultaneously with the corresponding predetermined MEMS scanning field of view, the variable field of view scanning system can be in the first field of view, the second field of view, ..., And between the last field of view (for example, the sixth field of view), scanning detection and imaging are performed sequentially and cyclically.

Fig. 3 shows a schematic structural diagram of a variable field of view scanning system according to a third exemplary embodiment of the present disclosure. The embodiment of Fig. 3 is similar to the embodiment of Fig. 2, but the only difference is that in the embodiment of Fig. 3, since the target area 60 itself can emit stronger infrared radiation or the variable field of view scanning system itself has a stronger Infrared detection capability, so it does not require additional laser sources and corresponding MEMS to irradiate objects in the target area.

Since the working principle in the embodiment of FIG. 3 is basically the same as the principle of receiving echo signals originating from objects in the target area 60 and performing corresponding imaging in the embodiment of FIG. 2 , only a brief introduction will be made below, and No need to go into details, and for detailed working principles, refer to the description of the embodiment in FIG. 2 .

As shown in FIG. 3 , the variable scanning system 300 may include a multi-curved rotating prism 10 , a light detector 51 , a lens 40 and a controller (not shown). As an example, the light detector 51 may be an infrared focal plane detector. In some embodiments, the infrared radiation signal originating from the target area 60 reflected by the multi-curved rotating prism 10 may be reflected to the light detector 50 via the reflector 31 . In some other embodiments, the reflector 31 may be omitted, so that the infrared radiation signal originating from the target area reflected by the multi-curved rotating prism 10 can be directly reflected to the photodetector 50 .

In the embodiment of FIG. 3 , multiple reflective curved surfaces on the multi-curved rotating prism 10 can be designed for different fields of view. In some embodiments, these fields of view may be similar or identical to the fields of view for which the plurality of reflective curved surfaces on the multi-curved rotational prism 10 in the embodiments of FIGS. , and the closer the field of view is to the axis of symmetry, the smaller the corresponding angle range of the field of view.

In addition, in some embodiments, different fields of view corresponding to different reflective curved prisms on the multi-curved prism 10 may have corresponding different or the same maximum imaging distances. In yet other embodiments, different fields of view may have different or the same minimum lateral imaging resolution, regardless of whether the longest imaging distances corresponding to the different fields of view are the same. Furthermore, in some embodiments as well, different maximum imaging distances may be combined with different field angle ranges. In particular, the smaller the field of view angle range, the longer the corresponding maximum imaging distance. Furthermore, in the example where the full field of view has a symmetry axis, the closer the field of view is to the symmetry axis, the smaller the corresponding angle range of the field of view and/or the longer the corresponding maximum imaging distance.

A controller (not shown) may at least be coupled to the above-mentioned multi-curved rotating prism 10 and light detector 51 for controlling these components.

In particular, the rotation of the multi-curved prism 10 can be controlled by the controller, so that the predetermined reflective curved surface on the multi-curved prism 10 (for example, the first, second, third, fourth, fifth or The sixth reflective curved surface) is oriented to allow the infrared radiation signal corresponding to the field of view to be reflected to the photodetector 51 via the predetermined reflective curved surface, so that the photodetector 51 generates an image of the corresponding field of view. Here, it still needs to be specially explained that during the infrared thermal imaging process of the above-mentioned photodetector 51 for different fields of view, the multi-curved rotating prism 10 and thus the various reflective curved surfaces on it remain stationary, so that the light detection The device 51 realizes the detection of the field of view corresponding to the predetermined reflective curved surface. Only when the thermal imaging detection of the predetermined field of view corresponding to the predetermined reflective curved surface by the photodetector 51 ends, will the multi-curved rotating prism 10 be further rotated to realize the next predetermined field of view corresponding to the next predetermined reflective curved surface. thermal imaging detection (that is, to further rotate the multi-curved rotating prism 10 so that the next predetermined reflective curved surface is oriented to allow the thermal imaging signal from the field of view corresponding to the next predetermined reflective curved surface to be reflected to photodetector 51).

For example, when using the first curved reflective surface 1 to perform infrared thermal imaging for the first field of view, the reflection of the first curved reflective surface 1 can be focused by the lens 40, then reflected by the reflector 31, reach the photodetector 51, and pass through The photodetector 50 generates infrared thermal imaging results corresponding to the first field of view. When using the first reflective curved surface 1 for infrared thermal imaging of the first field of view, the multi-curved rotating prism 10 and the reflective curved surface on it can remain stationary for a first period of time, so that the photodetector 51 can thereby generate the first image. Once the detection of the first field of view ends, the multi-curved rotating prism 10 can continue to rotate, for example, to make the second reflective curved surface 2 in a position facing the second field of view and remain stationary for a second period of time, so that the photodetector 51 A second image can thus be generated, wherein the second time period is different from the first time period. By analogy, the multi-curved rotating prism can continue to rotate, so as to realize the detection and imaging of the field of view corresponding to more reflective curved surfaces.

In the embodiment in which the multi-curved rotating prism 10 has 6 reflective curved surfaces, the third field of view corresponding to the third reflective curved surface 3 can be followed in the third time period, and the fourth reflective surface 4 can be obtained in the fourth time period. The corresponding fourth field of view, the fifth field of view corresponding to the fifth reflective curved surface 5 in the fifth time period, and the sixth field of view corresponding to the sixth reflective surface 6 in the sixth time period are detected, and respective corresponding Image. Similar to the embodiment in FIG. 1 , the above-mentioned first, second, third, fourth, fifth time periods, and sixth time periods are different from each other or do not overlap each other. In some embodiments, the later time period immediately follows the previous time period, for example, the second time period immediately follows the first time period, the third time period immediately follows the second time period, and so on. In this way, each field of view can be scanned and imaged at maximum speed. In still some embodiments, it is also possible that there is a predetermined time interval between the latter time period and the previous time period, which depends on design requirements.

As the multi-curved rotating prism 10 continues to rotate, after detecting and imaging the last field of view, it can return to detecting and imaging the first field of view. That is to say, by using the rotation of the multi-curved rotating prism 10, the variable field of view scanning system can be between the first field of view, the second field of view, ..., and the last field of view (for example, the sixth field of view) Scanning detection and imaging are performed sequentially and cyclically.

In the embodiment of FIG. 3 , the multi-curved rotating prism 10 is also operable to rotate clockwise or counterclockwise, so as to sequentially detect the fields of view corresponding to the plurality of reflective curved surfaces on the multi-curved rotating prism 10 and generate corresponding image. In some embodiments, these images may be presented to the user individually. In still other embodiments, these images can be stitched together and presented to the user.

The structure and working principle of the variable field of view scanning system according to the present disclosure have been described in detail above with reference to a number of example embodiments. It will be understood that through the multi-curved rotating prism designed in the present disclosure, detection imaging of multiple different fields of view can be realized. In particular, the angular ranges of the fields of view may vary for different field orientations. In particular, although the fields of view are different from each other and/or the furthest imaging distance is different, they can all maintain substantially the same minimum lateral imaging resolution. In particular, the field angle ranges of these fields of view may be associated with the furthest imaging distances of the corresponding fields of view. For example, the farther the imaging distance of the field of view is, the smaller the angle range of the field of view is. It is easy to understand that in long-distance detection, the design of reducing the field of view angle range can effectively improve the minimum lateral imaging resolution and reduce the power of the light source.

A flow chart of a variable field of view scanning method according to an example embodiment of the present disclosure will be briefly described below with reference to FIG. 4 .

As shown in FIG. 4, at block 410, first light from a first field of view is reflected by a first reflective curved surface of the polycurved rotational prism, wherein the first reflective curved surface is designed for the first field of view.

at block 420, receiving the first light with a light detector to generate a first image corresponding to the first field of view;

At block 430, second light from a second field of view is reflected by a second reflective curved surface of the multi-curved rotational prism, wherein the second reflective curved surface is designed for the second field of view, wherein the first field of view at least one of a field of view orientation and a field of view angle range different from the second field of view; and

At block 440, the second light is received with the light detector to generate a second image corresponding to the second field of view.

As mentioned above, in some embodiments, the multi-curved prism may further include more than two reflective curved surfaces including at least the first reflective curved surface and the second reflective curved surface, wherein each reflective curved surface is designed for different fields of view. In particular, the plurality of fields of view corresponding to the plurality of reflective curved surfaces may collectively constitute a full field of view, and the full field of view may have a symmetry axis. In particular, the first field of view and the second field of view may be located on the same side of the axis of symmetry, the second field of view being closer to the axis of symmetry than the first field of view but having a smaller The angle range of the field of view and the farther correspond to the farthest imaging distance. More particularly, the plurality of reflective curved surfaces may include a third reflective curved surface having a corresponding third field of view, and the light detector may generate a third image for the third field of view, wherein the first field of view, the The second field of view and the third field of view are located on the same side of the symmetry axis, and the angle ranges of the first, second, and third fields of view decrease sequentially, but the corresponding farthest imaging distances increase sequentially . As a non-limiting example, the furthest imaging distance corresponding to the first image is in the range of 20m-30m; the furthest imaging distance corresponding to the second image is in the range of 60m-75m; the furthest imaging distance corresponding to the third image is in the range of Within the range of 180m-220m. Although the furthest imaging distances are different for different fields of view, in some embodiments the minimum lateral imaging resolutions for these fields of view may be approximately the same, eg the difference between the minimum lateral imaging resolutions of the first image and the second image It may be within the range of ±10% of the minimum lateral imaging resolution of the first image.

In some embodiments, in the above block 410, it may further include: keeping the multi-curved rotating prism stationary for a first period of time to reflect the first light from the first field of view. In the above block 430, it may further include: keeping the multi-curved rotating prism stationary for a second time period to reflect the second light from the second field of view; wherein the second time period is different from the first Two time periods.

In some embodiments, the rotation of the multi-curved rotating prism can be controlled by a controller, so that the reflection of light from the plurality of viewing fields by the multiple reflective curved surfaces on the multi-curved rotating prism is performed sequentially and cyclically.

According to the design of the present disclosure, the variable field of view scanning method can be applied to different application scenarios with or without a laser source. In an embodiment of an application scenario where a laser source is required to irradiate the target area, the method may further include: using a laser to emit detection light of a predetermined wavelength; causing the reflective curved surface of the multi-curved rotating prism to reflect the detection light to the target area; and transmitting the probe light emitted from the laser by using a beam splitter, and reflecting the light from the multi-curved rotating prism to the photodetector. Alternatively, the method may further include: using a laser to emit probe light of a predetermined wavelength; using a micro-electromechanical scanning mirror (MEMS) to receive the probe light emitted from the laser, and project the probe light to the target area.

In an embodiment of an application scenario that does not require a laser source to irradiate the target area, the reflective curved surface of the multi-curved rotating prism can reflect the infrared radiation signal from the corresponding field of view of the target area to the photodetector without requiring an additional laser source The laser beam illuminates the target area.

The variable field of view scanning system and the variable field of view scanning method of the present disclosure have been described in detail above. It will be understood that the variable field of view scanning system and the variable field of view scanning method of the present disclosure can be applied in a radar system, for example to realize functions such as automatic driving and automatic navigation. Furthermore, the radar system may be included in a terminal device to provide radar detection or navigation functions for the terminal device. As a non-limiting example of a terminal device, the terminal device may include, for example, a vehicle, a drone, a robot, and the like. These terminal devices can be used, for example, in application scenarios such as vehicle automatic driving, aircraft autonomous flight, intelligent machine manufacturing, or logistics warehouse.

It will also be understood that the methods and apparatus described above are examples only. Although the description describes steps of a method in a particular order, this does not require or imply that operations must be performed in that particular order, or that all illustrated operations must be performed to achieve desired results, but rather, the depicted steps can Change the order of execution. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step for execution, and/or one step may be decomposed into multiple steps for execution.

While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive; the invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and practiced by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims.

In the claims, the word "comprising" does not exclude other elements and the indefinite article "a" or "an" does not exclude a plurality. A single element or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain features are recited in mutually different embodiments or in dependent claims does not indicate that a combination of these features cannot be used to advantage. The protection scope of the present application covers any possible combination of the individual features recited in the individual embodiments or in the dependent claims without departing from the spirit and scope of the application.

Furthermore, any reference signs in the claims shall not be construed as limiting the scope of the invention.

Claims

A variable field of view scanning system is characterized in that it comprises:

The multi-curved rotational prism has at least a first curved reflection surface and a second curved reflection surface, wherein the first curved reflection surface is designed for a first field of view, and the second curved reflection surface is designed for a second field of view, the at least one of a field orientation and a field angle range of the first field of view is different from the second field of view;

a light detector adapted to receive first light reflected from said first reflective curved surface to generate a first image corresponding to said first field of view, and to receive second light reflected from said second reflective curved surface , to generate a second image corresponding to the second field of view.
The variable field of view scanning system according to claim 1, wherein the difference between the minimum lateral imaging resolution of the first image and the second image is within 100% of the minimum lateral imaging resolution of the first image ±10% range.
The variable field of view scanning system according to claim 2, wherein the farthest imaging distance in the first field of view corresponding to the first image is the same as that in the second field of view corresponding to the second image The furthest imaging distance is different.
The variable field of view scanning system according to any one of claims 1-2, wherein the multi-curved rotating prism has more than two reflective curved surfaces including the first reflective curved surface and the second reflective curved surface, The plurality of reflective curved surfaces are designed for a plurality of fields of view different from each other.
The variable field of view scanning system according to claim 4, wherein the entire field of view formed by the plurality of fields of view has an axis of symmetry, and the first field of view and the second field of view are located on the axis of symmetry On the same side of , the second field of view is closer to the symmetry axis than the first field of view, but has a smaller field of view angle range and/or a farther maximum imaging distance.
The variable field of view scanning system according to claim 5, wherein the multi-curved rotating prism further comprises a third reflective curved surface, the third reflective curved surface is designed for a third field of view, and the photodetector is further controlled by configured to receive third light reflected from the third reflective surface to generate a third image corresponding to the third field of view,

Wherein the first field of view, the second field of view and the third field of view are located on the same side of the symmetry axis, the angle ranges of the first, second, and third fields of view decrease sequentially, but The corresponding furthest imaging distance increases sequentially.
The variable field of view scanning system according to claim 6, wherein said multi-curved rotating prism further comprises a fourth reflective curved surface, said fourth reflective curved surface is designed for a fourth field of view, said fourth field of view is identical to The first field of view is symmetrical about the axis of symmetry.
The variable field of view scanning system according to any one of claims 6-7, wherein the furthest imaging distance corresponding to the first image is in the range of 20m-30m, and the furthest imaging distance corresponding to the second image is The distance is within the range of 60m-75m, and the furthest imaging distance corresponding to the third image is within the range of 180m-220m.
The variable field of view scanning system according to any one of claims 1-3, 5-7, wherein said light detector is configured to receive said first light during a first time period and generate said a first image, and receiving the second light and generating the second image during the second time period, the first time period being different than the second time period.
The variable field of view scanning system of claim 9 , wherein during the transition period from the first time period to the second time period, the multi-curved rotating prism is operable to rotate to adjust orientation of the multi-curved prism, while the multi-curved prism remains stationary during the first time period and the second time period.
The variable field of view scanning system according to claim 1, further comprising:

a laser for emitting a probe beam to the multi-curved rotating prism; and

A beam splitter, arranged between the laser and the multi-curved rotating prism, transmits the detection beam emitted from the laser and reflects light from the multi-curved rotating prism to the photodetector.
The variable field of view scanning system according to claim 1, further comprising:

a laser for emitting probe light;

a micro-electromechanical scanning mirror (MEMS), configured to receive the detection light emitted from the laser, and project the detection light to a predetermined target area in a scanning manner,

Wherein the multi-curved rotating prism is configured to adjust the orientation of the corresponding reflective curved surface according to the scanned predetermined target area, so as to receive light from the predetermined target area and reflect the light of the predetermined target area to the light detector.
A radar system, comprising the variable field of view scanning system according to any one of claims 1-12.
A terminal device comprising the radar system according to claim 13.
The terminal device according to claim 14, said terminal device comprising at least one of a vehicle, a drone, and a robot.
A variable field of view scanning method based on a multi-curved rotating prism, characterized in that it includes:

reflecting first light from a first field of view through a first reflective curved surface of the multi-curved prism, wherein the first reflective curved surface is designed for the first field of view;

receiving the first light with a photodetector to generate a first image corresponding to the first field of view;

second light from a second field of view is reflected by a second curved reflective surface of the multi-curved prism, wherein the second curved reflective surface is designed for the second field of view, wherein the field of view of the first field of view is oriented and at least one of a field of view angular range different from the second field of view; and

The second light is received with the light detector to generate a second image corresponding to the second field of view.
The variable field of view scanning method according to claim 16, wherein reflecting the first light from the first field of view through the first reflective curved surface of the multi-curved rotating prism comprises: keeping the multi-curved surface rotating for a first time period a prism is stationary to reflect first light from said first field of view; and

Reflecting the second light from the second field of view through the second reflective curved surface of the multi-curved rotating prism includes: holding the multi-curved rotating prism stationary for a second period of time to reflect light from the second field of view second light;

Wherein the second time period is different from the second time period.
The variable field of view scanning method according to any one of claims 16-17, wherein the difference between the minimum lateral imaging resolutions of the first image and the second image is within the minimum lateral imaging resolution of the first image within ±10% of imaging resolution.
According to the variable field of view scanning method according to any one of claims 16-17, the farthest imaging distance in the first field of view corresponding to the first image is the second image corresponding to the second image. The farthest imaging distances in the two fields of view are different.
The variable field of view scanning method according to any one of claims 16-17, wherein the multi-curved rotating prism has more than two reflective curved surfaces including the first reflective curved surface and the second reflective curved surface, The plurality of reflective curved surfaces are designed for different multiple fields of view, and the entire field of view formed by the plurality of fields of view has an axis of symmetry, and the method also includes:

The rotation of the multi-curved rotating prism is controlled so that the reflections of the plurality of reflective curved surfaces on the light of the plurality of viewing fields are sequentially and cyclically performed.
The variable field of view scanning method according to claim 20, wherein the first field of view and the second field of view are located on the same side of the axis of symmetry, and the second field of view is opposite to the first field of view The field is closer to the axis of symmetry, but has a smaller angular range of the field of view and a corresponding furthest imaging distance further away.
The variable field of view scanning method according to claim 20, wherein the multi-curved rotating prism further comprises a third reflective curved surface, the third reflective curved surface is designed for a third field of view, and the photodetector is also controlled by configured to receive third light reflected from the third reflective surface to generate a third image corresponding to the third field of view,

Wherein the first field of view, the second field of view and the third field of view are located on the same side of the symmetry axis, the angle ranges of the first, second, and third fields of view decrease sequentially, but The corresponding furthest imaging distance increases sequentially.
The variable field of view scanning method according to claim 22, wherein the furthest imaging distance corresponding to the first image is in the range of 20m-30m; the furthest imaging distance corresponding to the second image is in the range of 60m-75m within the range; the farthest imaging distance corresponding to the third image is within the range of 180m-220m.
The variable field of view scanning method according to any one of claims 16-17, further comprising:

Using a laser to emit a probe beam;

causing the reflective curved surface of the multi-curved prism to reflect the probe beam to a target area; and

A beam splitter is used to transmit the probe beam emitted from the laser, and to reflect the light from the multi-curved rotating prism to the photodetector.
The variable field of view scanning method according to any one of claims 16-17, further comprising:

Using a laser to emit a probe beam;

The detection light emitted from the laser is received by a micro-electromechanical scanning mirror (MEMS), and the detection light is projected to a target area in a scanning manner.