CN210199305U

CN210199305U - Scanning module, range unit and movable platform

Info

Publication number: CN210199305U
Application number: CN201920266246.1U
Authority: CN
Inventors: Yalin Chen; 陈亚林; Shuai Dong; 董帅; Xiaoping Hong; 洪小平
Original assignee: SZ DJI Technology Co Ltd
Current assignee: SZ DJI Technology Co Ltd
Priority date: 2019-03-01
Filing date: 2019-03-01
Publication date: 2020-03-27
Anticipated expiration: 2029-03-01

Abstract

The utility model provides a scanning module, range unit and movable platform, the scanning module includes at least one optical element and at least one driver, at least one optical element is used for changing the direction of propagation of the light beam of launching by the range unit, at least one the driver is used for driving at least one target optical element among the optical element moves, at least one optical element includes first optical element, first optical element is for at least one other optical element among the optical element is close to the light beam gets into the position of scanning module, just first optical element is used for the collimation the light beam and change the direction of propagation of the light beam after the collimation. Therefore, according to the utility model discloses a scanning module, range unit and movable platform can realize obtaining higher optical characteristic with lower cost, and effectively reduce the volume.

Description

Scanning module, range unit and movable platform

Technical Field

The utility model relates to a range finding technical field especially relates to scanning module, range unit and movable platform.

Background

Laser radar and laser ranging are sensing systems for the outside world, and spatial distance information in the transmitting direction can be obtained. The laser radar is a device for sensing surrounding objects by utilizing laser beams, reflects the positions and the appearances of the surrounding objects in the form of point cloud data, and has the characteristics of high measurement resolution, high speed, small volume, light weight and the like. The mechanical scanning type laser radar is a laser radar which is widely used and can realize high-speed scanning, and the mechanical scanning type laser radar comprises: rotating mirror scanning, galvanometer scanning, optical wedge scanning, and the like. The laser radar adopting the optical mechanical rotation scanning mode can collimate laser and change the propagation direction of the laser, so that the interior of the laser radar comprises a collimating lens and a plurality of optical wedges. These core optics assemblies are expensive, difficult to mass produce due to high hardware cost, and have yet to be improved in stability.

Therefore, the mechanical rotary laser radar in the prior art has the problems of high cost, large volume and unstable performance of optical devices, and the development of the mechanical rotary laser radar is limited.

SUMMERY OF THE UTILITY MODEL

The present invention has been made in view of the above problems. The utility model provides a scanning module, range unit and movable platform to optical device among the solution laser radar is with high costs, bulky and unstable problem of performance.

According to the utility model discloses an aspect provides a scanning module, scanning module includes:

the device comprises at least one optical element and at least one driver, wherein the at least one optical element is used for changing the propagation direction of a light beam emitted by a distance measurement module, the at least one driver is used for driving a target optical element in the at least one optical element to move, the at least one optical element comprises a first optical element, the first optical element is close to the position where the light beam enters the scanning module relative to other optical elements in the at least one optical element, and the first optical element is used for collimating the light beam and changing the propagation direction of the collimated light beam.

Optionally, the first optical element includes a curved surface and a first inclined surface, the curved surface is a light incident surface of the first optical element for the light beam, and the first inclined surface is a light emitting surface of the first optical element for the collimated light beam.

Optionally, at least one of the optical elements further comprises a second optical element for changing the propagation direction of the output beam of the first optical element.

Optionally, the second optical element comprises a pair of opposed non-parallel surfaces, the thickness of the second optical element varying in at least one radial direction.

Optionally, the second optical element comprises a flat surface and a second inclined surface;

the second inclined plane is a surface of the second optical element close to the first optical element, and the plane is a surface of the second optical element far from the first optical element, or the plane is a surface of the second optical element close to the first optical element, and the second inclined plane is a surface of the second optical element far from the first optical element.

Optionally, the curved surface comprises a spherical surface or an aspherical surface.

Optionally, the spherical surface comprises a convex spherical surface or a concave spherical surface.

According to the utility model discloses a second aspect of the embodiment provides a distance measuring device, include:

the scanning module according to the first aspect of the embodiment of the present invention;

the distance measuring module is used for emitting a light beam to the scanning module, the scanning module is used for changing the propagation direction of the light beam and then emitting the light beam, the light beam reflected back by the detection object enters the distance measuring module after passing through the scanning module, and the distance measuring module is used for determining the distance between the detection object and the distance measuring device according to the reflected light beam.

Optionally, the ranging module comprises a transmitter for transmitting the light beam;

the first optical element in the scanning module is arranged on an emergent light path of the emitter and used for collimating the light beam emitted from the emitter.

Optionally, the distance measuring module comprises a transmitter and a third optical element, the transmitter is used for transmitting the light beam;

the third optical element is arranged on an emergent light path of the emitter and is used for collimating the light beam emitted from the emitter;

the first optical element is arranged on an emergent light path of the third optical element and is used for collimating the light beam output by the third optical element.

Optionally, the third optical element comprises a pair of opposing non-parallel surfaces, the pair of surfaces of the third optical element comprising at least one curved surface.

According to the utility model discloses a third aspect provides a range unit, includes:

the distance measuring device is characterized by further comprising an optical element, the optical element is used for collimating the light beam emitted by the distance measuring module and changing the propagation direction of the collimated light beam, and the optical element is arranged in the scanning module or the distance measuring module.

Optionally, the optical element includes a curved surface and an inclined surface, the curved surface is a light incident surface of the optical element for the light beam, and the inclined surface is a light emergent surface of the optical element for the collimated light beam.

According to the utility model discloses a fourth aspect of the embodiment provides a movable platform, include:

a platform body; and

according to the second aspect or the third aspect of the embodiment of the present invention, the distance measuring device is installed on the platform body.

The utility model discloses scanning module, range unit and movable platform make setting between the optical element compacter through the shape that changes optical element, realize obtaining higher optical characteristic with lower cost, and effectively reduce the volume of whole device, are favorable to improving the performance of whole device.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent by describing in more detail embodiments of the present invention with reference to the attached drawings. The accompanying drawings are included to provide a further understanding of the embodiments of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the invention and not to limit the invention. In the drawings, like reference numbers generally represent like parts or steps.

FIG. 1 is a schematic view of a distance measuring device;

fig. 2 is a schematic view of a distance measuring device according to an embodiment of the present invention;

fig. 3 is a schematic view of another distance measuring device according to an embodiment of the present invention;

FIG. 4 is a schematic block diagram of a ranging device;

FIG. 5 is a schematic diagram of an embodiment of a distance measuring device using coaxial optical paths.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. It is to be understood that the described embodiments are merely exemplary of the present invention and are not intended to limit the invention to the particular embodiments described herein. Based on the embodiments of the present invention described in the present application, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present invention.

The mechanical scanning type laser radar realizes the laser scanning function by controlling the movement of laser in space through mechanical scanning. In the laser radar, an optical module comprising an optical element controls the propagation direction and convergence and divergence of laser in a system, so the structural form of the optical element determines the structural form of the whole laser radar system, and the optical element has great influence on the cost, the volume and the performance of the whole laser radar system.

Referring to fig. 1, fig. 1 shows a schematic view of a distance measuring device. As shown in fig. 1, the distance measuring apparatus 100 includes a scanning module 110 and a distance measuring module 120, the distance measuring module 120 includes a light source LD1 and an optical element L11, the scanning module 110 includes optical elements L12 and L13, and a driver for driving the optical elements L12 and L13. The optical elements L11, L12, and L13 are all located at one side of the light source LD 1. The light source LD1 is used for generating and emitting light beams, and after the light beams pass through the optical elements L11, L12 and L13, the light beams are collimated and the light paths of the light beams are changed and emitted to different directions; the driver drives the target one of the optical elements L12, L13 to achieve scanning in different directions, forming a scanning field of view.

In one embodiment, the light source LD1 may emit a laser beam. The laser beam emitted by the light source LD1 is a narrow bandwidth beam having a wavelength outside the visible range.

In one embodiment, the light source LD1(Laser Diode) may be a semiconductor Laser.

In one embodiment, the optical element L11 may be a collimating element L11, which is used to collimate the light beam emitted from the light source LD1 and collimate the light beam emitted from the light source LD1 into parallel light.

In one embodiment, the optical elements L12 and L13 may be optical wedges for changing the transmission direction of the parallel light collimated by the collimating element L11 and projecting to the external environment.

In the distance measuring device 100 shown in fig. 1, a single collimating element (e.g., an optical element L11) is used to collimate the light beam generated by the light source, and in order to ensure that the collimating requirement of the collimating element (e.g., a single lens) is high in practical application with a good collimating effect, the size of the scanning module is large due to the use of a plurality of optical elements, and the mechanical structure is complex. In order to satisfy the demand of present increasingly reduce cost, compact structure and simplification, based on the above-mentioned consideration, the utility model provides a scanning module. Referring to fig. 2, fig. 2 shows a schematic diagram of a distance measuring device according to an embodiment of the present invention. As shown in fig. 2, the ranging apparatus 200 includes: a light source LD2 (the distance measuring module includes a light source LD2) and a scanning module 210.

Wherein the scanning module 210 comprises at least one optical element for changing the propagation direction of the light beam emitted by the distance measuring module, and at least one driver (not shown) for driving a target optical element of the at least one optical element to move, the at least one optical element comprises a first optical element L21, the first optical element L21 is close to the position where the light beam enters the scanning module 210 relative to other optical elements of the at least one optical element, and the first optical element L21 is used for collimating the light beam and changing the propagation direction of the collimated light beam. Wherein the beam comprises, for example, laser pulses.

Wherein, through improving optical element's shape, become the first optical element L21 that can realize the single component of both functions simultaneously with the component of the change beam direction with the collimation component, first optical element L21 both can collimate the light beam and can change the propagation direction of light beam, relative to the optical element that only can collimate to the light beam or only can change the propagation direction of light beam, first optical element L21 can further reduce the cost of scanning module, make the structure of scanning module simple, compact.

Optionally, the first optical element L21 includes a curved surface and a first inclined surface, the curved surface is an incident surface of the first optical element L21 for the light beam, and the first inclined surface is an exit surface of the first optical element L21 for the collimated light beam. The structure of the first optical element L21 can collimate the incident light beam and change the transmission direction of the collimated light beam, and the effect of two optical elements which can only realize one function can be achieved by adopting one first optical element, so that the number of the optical elements of the scanning module can be reduced, the structure of the scanning module is simpler, and the volumes of the scanning module and the distance measuring device are further reduced.

Optionally, the curved surface comprises a spherical surface or an aspherical surface. When the curved surface of the first optical element is an aspheric surface, the imaging effect is good, various aberrations can be eliminated, and the number of the optical elements can be reduced; when the curved surface of the first optical element is a spherical surface, the processing cost is low; the spherical surface or the aspherical surface can be selected according to the actual requirement to balance the imaging effect and the processing cost. Optionally, the spherical surface comprises a convex spherical surface or a concave spherical surface. The diopters of the convex spherical surface or the concave spherical surface are different, the convex spherical surface can focus light, the concave spherical surface can disperse light, and the convex spherical surface or the concave spherical surface can be selected according to actual needs to form a needed light path.

In one embodiment, referring again to fig. 2, the first optical element L21 in fig. 2 includes a curved surface and a first inclined surface, and the light beam emitted from the light source LD2 enters the first optical element L21 through the curved surface of the first optical element L21, is collimated by the first optical element L21 and changes the direction of the light beam to become parallel light, and is emitted from the first inclined surface of the first optical element L21. The shape of the first optical element can be understood as integrating the collimating element L11 and the optical element L12 in fig. 1, the collimating element L11 is a collimating lens, the optical element L12 is a wedge, the plane end of the wedge L12 is processed into a plane shape of a curved surface of the collimating lens L11, the inclined surface of the wedge L12 is unchanged, so that the first optical element L21 can be obtained, the structure can effectively reduce the volume of the scanning module, and the mechanism of the laser radar device is compact or simplified.

It should be noted that the specific shape of the first optical element is only an example, and the first optical element also includes other optical elements that can achieve the collimation of the light beam and the change of the propagation direction of the light beam at the same time, and is not limited herein.

Optionally, at least one of the optical elements further comprises a second optical element L22, the second optical element L22 being configured to change a propagation direction of the output light beam of the first optical element L21. The first optical element L21 is close to the light source LD2 relative to the second optical element L22, that is, close to the position where the light beam emitted from the LD2 enters the scanning module 210.

Optionally, the second optical element L22 includes a pair of opposing non-parallel surfaces, the thickness of the second optical element varying in at least one radial direction.

Optionally, the second optical element L22 includes a flat surface and a second inclined surface; the second inclined plane is a plane of the second optical element L22 close to the first optical element L21 and the plane is a plane of the second optical element L22 away from the first optical element L21, or the plane is a plane of the second optical element L22 close to the first optical element L21 and the second inclined plane is a plane of the second optical element L22 away from the first optical element L21.

After the parallel light beams emitted by the first optical element L21 pass through the second optical element L22, the direction of the light path changes, and the light beams can be emitted in any direction by matching the first optical element L21 with the second optical element L22. It is understood that the number of the first optical element and the second optical element can be set according to practical situations, and is not limited herein.

Alternatively, the second optical element may be a wedge, convex lens, concave lens, mirror, or other optical element that alters the optical path.

Wherein, referring again to fig. 2, the output light beam of the first optical element L21 enters the plane or slope of the second optical element L22 to change the propagation direction of the output light beam of the first optical element L21. The driver drives the target optical element of the first optical element L21 and the second optical element L22 to realize scanning in different directions, forming a scanning field of view. In practical applications, the speed of whether the optical element is fixed or rotated is different according to different scanning fields to be obtained, and the target optical element is the optical element which needs to be driven by a driver to obtain a certain rotating speed. In fig. 2, the first optical element L21 and/or the second optical element L22 may be driven at the same or different speeds using a driver as needed to obtain the respective scan fields of view. Alternatively, the drive may comprise a motor or other drive means.

As can be seen from the foregoing, the distance measuring device 200 shown in fig. 2 has a reduced number of optical elements compared to the distance measuring device 100 shown in fig. 1, so that the scanning module 210 and the distance measuring device 200 have a simple structure and a smaller volume, thereby reducing the cost of the scanning module 210 and the distance measuring device 200. In order to ensure that the good collimation effect has a high requirement on the collimation of the optical element in practical application, that is, the requirement on the curved surface of the first optical element is high, and in order to further reduce the processing cost and also take the collimation effect into consideration, the scanning module can also combine the schemes described in fig. 1 and fig. 2, so that the cost is further reduced while the collimation effect is ensured. Based on the above consideration, referring to fig. 3, fig. 3 shows a schematic diagram of a distance measuring device according to an embodiment of the present invention. As shown in fig. 3, in contrast to fig. 1, the collimating element L11 in fig. 1 is retained in fig. 3, and the optical element L12 in fig. 1 is replaced with the first optical element L22 in fig. 2; in comparison with fig. 2, a third optical element L31 is added between the first optical element L22 and the light source LD3 in fig. 2 in fig. 3. The distance measuring device shown in fig. 3 can perform collimation function due to the third optical element L31 (i.e. the remaining collimating element) and the first optical element L32, that is, the structure in fig. 3 can perform collimation on the light beam emitted by the LD3 twice, which is better than performing collimation only once, so that the requirement for each collimation can be reduced, so that the requirement for the curved surface of the optical element is reduced to save the processing cost of the curved surface. Therefore, the distance measuring device in fig. 3 has better collimation effect and lower cost compared with the distance measuring device shown in fig. 1; the collimation is better compared to the distance measuring device shown in fig. 2.

Referring to fig. 3, an embodiment of the present invention provides a distance measuring device 300, including:

the scanning module 310 according to the embodiment of the present invention;

the distance measuring module 320, the distance measuring module 320 is configured to emit a light beam (such as a laser pulse) to the scanning module 310, the scanning module 310 is configured to change a propagation direction of the light beam and emit the light beam, the light beam reflected by the object passes through the scanning module 310 and then enters the distance measuring module 320, and the distance measuring module 320 is configured to determine a distance between the object and the distance measuring device 300 according to the reflected light beam.

Optionally, the distance measuring module 320 includes a light source LD3, the light source LD3 is used for emitting the light beam (such as laser pulse); the first optical element L32 in the scanning module 310 is disposed on the outgoing light path of the light source LD3 and is used for collimating the light beam emitted from the light source LD 3.

Optionally, the distance measuring module 320 includes a light source LD3 and a third optical element L31, the light source LD3 is configured to emit the light beam;

the third optical element L31 is arranged on an emergent light path of the light source LD3 and is used for collimating the light beam emitted from the light source LD 3;

the first optical element L32 is disposed on the light emitting path of the third optical element L31, and is configured to collimate the light beam output by the third optical element L31.

Optionally, the third optical element L31 includes a pair of opposing non-parallel surfaces, the pair of surfaces of the third optical element including at least one curved surface.

In one embodiment, the third optical element L31 may include two curved surfaces.

Alternatively, the light source LD3 may be an emitter, for example, a semiconductor laser.

In one embodiment, referring to fig. 3, the scan module 310 includes: at least one optical element and at least one driver (not shown); at least one of the optical elements is used for changing the propagation direction of the light beam emitted by the distance measurement module 320, at least one of the drivers is used for driving a target optical element of the at least one of the optical elements to move, the at least one of the optical elements includes a first optical element L32, the first optical element L32 is close to the position where the light beam enters the scanning module 310 relative to other optical elements of the at least one of the optical elements, and the first optical element L32 is used for collimating the light beam and changing the propagation direction of the collimated light beam.

Optionally, the scanning module 310 further includes a second optical element L33, and the second optical element L33 is configured to change the propagation direction of the output light beam of the first optical element L32.

Optionally, the second optical element L33 includes a pair of opposing non-parallel surfaces, and the thickness of the second optical element L33 varies along at least one radial direction.

Optionally, the second optical element L33 includes a flat surface and a second inclined surface; the second inclined plane is a plane of the second optical element L33 close to the first optical element L32 and the plane is a plane of the second optical element L33 away from the first optical element L32, or the plane is a plane of the second optical element L33 close to the first optical element L32 and the second inclined plane is a plane of the second optical element L33 away from the first optical element L32.

After the parallel light beams emitted by the first optical element L32 pass through the second optical element L33, the direction of the light path changes, and the light beams can be emitted in any direction by matching the first optical element L32 with the second optical element L33. It is understood that the number of the first optical element and the second optical element can be set according to practical situations, and is not limited herein.

In one embodiment, referring to fig. 3, a third optical element L31, a first optical element L32, and a second optical element L33 are all located on one side of the light source LD3, the third optical element L31 may be a collimating element including a curved surface and a flat surface, the flat surface of the third optical element L31 is used as an incident surface of the light beam emitted by the light source LD3, the curved surface of the third optical element L31 is used as an exit surface of the light beam emitted by the light source LD3, and the incident surface of the first optical element L32 for the light beam emitted by the distance measuring module 320 (i.e., the light beam emitted by the light source LD 3) is opposite to the light source LD 3; the first optical element L32 includes a curved surface and a first inclined surface, the curved surface of the first optical element L32 is an incident surface of the first optical element L32 for the light beam emitted by the distance measuring module 320 (i.e., the light beam emitted by the light source LD 3), and is opposite to a surface of the third optical element L31 from which the collimated light beam emitted by the light source LD3 exits, and the first inclined surface is an emergent surface of the first optical element for the light beam emitted by the distance measuring module 320 (i.e., the light beam emitted by the light source LD 3), and is close to the second optical element L33 relative to the curved surface; the second optical element L33 may be an optical wedge including a plane surface and a second inclined surface, and both the plane surface and the second inclined surface of the second optical element L33 may be used as a light incident surface or a light emergent surface.

The light source LD3 emits a light beam, the light beam enters the third optical element L31 through the plane of the third optical element L31, the light beam is collimated by the third optical element L31, becomes a parallel light beam and is emitted from the curved surface of the third optical element L31; then enters the first optical element L32 through the curved surface of the first optical element L32, and after the first optical element L32 collimates the light beam and changes the propagation direction of the light beam, the light beam which is collimated again and changed in direction is emitted from the first inclined surface of the first optical element L32; the light beam enters the second optical element L33 through one surface of the second optical element L33, and the second optical element L33 changes the propagation direction of the light beam and then exits through the other surface of the second optical element L33. The driver drives the target optical element of the first optical element L32 and the second optical element L33 to realize scanning in different directions to form a scanning field of view.

In the manufacturing process of the optical element, the processing cost of the aspherical surface is relatively high, and the processing cost similar to that of the spherical surface is relatively low. Because the third optical element L31 is reserved in the above embodiment for collimation, in the process of light beam propagation, the light beam is collimated twice by the third optical element L31 and the first optical element L32, so that a stable and good collimation effect can be obtained, and the requirement of each collimation process on the curved surface of the optical element can be correspondingly reduced, thereby the curved surface processing requirement of the corresponding optical element can be reduced, and the purpose of reducing the cost can be achieved.

Optionally, the curved surface of the third optical element L31 and/or the first optical element L32 may be a spherical surface or an aspherical surface. Wherein, the spherical surface can be a convex spherical surface or a concave spherical surface. It is understood that the material and specific surface type parameters of the curved surface of the collimating element and/or the first optical element can be set according to practical situations and needs, and are not limited herein.

In one embodiment, the curved surfaces of the third optical element L31 and the first optical element L32 are spherical, so that the aberration and spherical aberration are smaller, and higher optical characteristics can be obtained at lower cost.

It is understood that the position of the first optical element can be applied to the distance measuring module, in addition to the description of the embodiments of the present invention. That is, the optical element for collimating and changing the propagation direction of the light beam can be disposed in the scanning module, and also disposed in the distance measuring module.

Specifically, the utility model also provides a range unit, this range unit includes: the distance measuring device comprises a scanning module and a distance measuring module, wherein the distance measuring module is used for emitting a light beam to the scanning module, the light beam reflected back by a detector is incident to the distance measuring module after passing through the scanning module, the distance measuring module is used for determining the distance between the detector and the distance measuring device according to the reflected light beam, the distance measuring device further comprises an optical element, the optical element is used for collimating the light beam emitted by the distance measuring device and changing the propagation direction of the collimated light beam, and the optical element is arranged in the scanning module or the distance measuring module. Wherein, among this range unit with the aforesaid the utility model discloses a same or similar content of range unit in two embodiments can follow the above-mentioned explanation, simultaneously, optical element's content can refer to the aforesaid the utility model discloses a corresponding content of first optical element in two embodiments, no longer describe here.

It should be noted that elements or combinations of elements which perform the same or similar functions in the various embodiments herein may be substituted for each other. As in the embodiments shown in fig. 2 and 3, elements or combinations of elements that perform the same or similar functions as in fig. 4 and 5 below may equally be used in the embodiments shown in fig. 4 and 5. Such as the first optical element, the second optical element, the third optical element and their combination, the scanning module, and the distance measuring module, can replace the same or similar parts in the embodiments shown in fig. 4 and 5. Meanwhile, the embodiments shown in fig. 4 and 5 may also assist in explaining the same or similar parts as those in the embodiments of the present invention, for example, application scenarios. The following may be referred to with respect to the contents shown in fig. 4 and 5.

The utility model provides a range unit can be used for the outside environmental information of sensing, for example, distance information, azimuth information, reflection intensity information, speed information etc. of environment target. In one implementation, the ranging device may detect the distance of the probe to the ranging device by measuring the Time of Flight (TOF), which is the Time-of-Flight Time, of light traveling between the ranging device and the probe. Alternatively, the distance measuring device may detect the distance from the probe to the distance measuring device by other techniques, such as a distance measuring method based on phase shift (phase shift) measurement or a distance measuring method based on frequency shift (frequency shift) measurement, which is not limited herein.

For ease of understanding, the following describes an example of the ranging operation with reference to the ranging apparatus 400 shown in fig. 4.

As shown in fig. 4, ranging apparatus 400 may include a transmitting circuit 410, a receiving circuit 420, a sampling circuit 430, and an arithmetic circuit 440.

The transmit circuit 410 may transmit a sequence of light pulses (e.g., a sequence of laser pulses). The receiving circuit 420 may receive the optical pulse train reflected by the detected object, perform photoelectric conversion on the optical pulse train to obtain an electrical signal, and output the electrical signal to the sampling circuit 430 after processing the electrical signal. The sampling circuit 430 may sample the electrical signal to obtain a sampling result. The arithmetic circuit 440 may determine the distance between the distance measuring device 400 and the detected object based on the sampling result of the sampling circuit 430.

Optionally, the distance measuring apparatus 400 may further include a control circuit 450, and the control circuit 450 may implement control of other circuits, for example, may control an operating time of each circuit and/or perform parameter setting on each circuit, and the like.

It should be understood that, although the distance measuring device shown in fig. 4 includes a transmitting circuit, a receiving circuit, a sampling circuit and an arithmetic circuit for emitting a light beam to detect, the embodiments of the present application are not limited thereto, and the number of any one of the transmitting circuit, the receiving circuit, the sampling circuit and the arithmetic circuit may be at least two, and the at least two light beams are emitted in the same direction or in different directions respectively; the at least two light paths may be emitted simultaneously or at different times. In one example, the light emitting chips in the at least two transmitting circuits are packaged in the same module. For example, each transmitting circuit comprises a laser emitting chip, and the dei e of the laser emitting chips in the at least two transmitting circuits are packaged together and accommodated in the same packaging space.

In some implementations, in addition to the circuit shown in fig. 4, the distance measuring device 400 may further include a scanning module (not shown) for changing the propagation direction of at least one laser pulse sequence emitted from the emitting circuit.

The module including the transmitting circuit 410, the receiving circuit 420, the sampling circuit 430 and the computing circuit 440, or the module including the transmitting circuit 410, the receiving circuit 420, the sampling circuit 430, the computing circuit 440 and the control circuit 450 may be referred to as a ranging module, which may be independent of other modules, for example, a scanning module.

The distance measuring device can adopt a coaxial light path, namely the light beam emitted by the distance measuring device and the reflected light beam share at least part of the light path in the distance measuring device. For example, at least one path of laser pulse sequence emitted by the emitting circuit changes the transmission direction through the scanning module to be emitted, and the laser pulse sequence reflected by the detector enters the receiving circuit after passing through the scanning module. Alternatively, the distance measuring device may also adopt an off-axis optical path, that is, the light beam emitted by the distance measuring device and the reflected light beam are transmitted along different optical paths in the distance measuring device. FIG. 5 is a schematic diagram of one embodiment of a distance measuring device using coaxial optical paths.

The distance measuring device 500 comprises a distance measuring module 510, and the distance measuring module 510 comprises an emitter 503 (which may comprise the above-mentioned emitting circuit), a collimating element 504, a detector 505 (which may comprise the above-mentioned receiving circuit, sampling circuit and arithmetic circuit), and a light path changing element 506. The distance measuring module 510 is used for emitting a light beam, receiving a return light, and converting the return light into an electrical signal. Wherein the emitter 503 may be configured to emit a sequence of light pulses. In one embodiment, the transmitter 503 may transmit a sequence of laser pulses. Alternatively, the emitter 503 emits a laser beam that is a narrow bandwidth beam having a wavelength outside the visible range. The collimating element 504 is disposed on an emitting light path of the emitter, and is configured to collimate a light beam emitted from the emitter 503, and collimate the light beam emitted from the emitter 503 into a parallel light to be emitted to the scanning module. The collimating element is also for converging at least a portion of the return light reflected by the detector. The collimating element 504 may be a collimating lens or other element capable of collimating a light beam.

In the embodiment shown in fig. 5, the transmit and receive optical paths within the ranging apparatus are combined by the optical path altering element 506 before the collimating element 504, so that the transmit and receive optical paths may share the same collimating element, making the optical path more compact. In other implementations, the emitter 503 and the detector 505 may use respective collimating elements, and the optical path changing element 506 may be disposed in the optical path after the collimating elements.

In the embodiment shown in fig. 5, since the beam aperture of the outgoing beam from the transmitter 503 is small and the beam aperture of the return beam received by the distance measuring device is large, the optical path changing element can adopt a mirror with a small area to combine the transmission optical path and the reception optical path. In other implementations, the optical path changing element may also be a mirror with a through hole for transmitting the outgoing light from the emitter 503, and a mirror for reflecting the return light to the detector 505. Therefore, the shielding of the bracket of the small reflector to the return light can be reduced in the case of adopting the small reflector.

In the embodiment shown in fig. 5, the optical path altering element is offset from the optical axis of the collimating element 504. In other implementations, the optical path altering element may also be located on the optical axis of the collimating element 504.

The distance measuring device 500 further includes a scanning module 502. The scanning module 502 is disposed on the outgoing light path of the distance measuring module 510, and the scanning module 502 is configured to change the transmission direction of the collimated light beam 519 emitted from the collimating element 504, project the collimated light beam to the external environment, and project the return light beam to the collimating element 504. The return light is converged by the collimating element 504 onto the detector 505.

In one embodiment, the scanning module 502 can include at least one optical element for changing the propagation path of the light beam, wherein the optical element can change the propagation path of the light beam by reflecting, refracting, diffracting, etc. the light beam. For example, the scan module 502 may include a lens, mirror, prism, galvanometer, grating, liquid crystal, optical phased Array (optical phased Array), or any combination thereof. In one example, at least a portion of the optical element is moved, for example, by a driving module, and the moved optical element can reflect, refract, or diffract the light beam to different directions at different times. In some embodiments, the plurality of optical elements of the scanning module 502 can rotate or oscillate about a common axis 509, with each rotating or oscillating optical element serving to constantly change the direction of propagation of an incident beam. In one embodiment, the optical elements of the scanning module 502 may rotate at different rotational speeds or oscillate at different speeds. In another embodiment, at least some of the optical elements of the scanning module 502 may rotate at substantially the same rotational speed. In some embodiments, the optical elements of the scanning module may also be rotated about different axes. In some embodiments, the optical elements of the scanning module can also rotate in the same direction, or rotate in different directions; or in the same direction, or in different directions, without limitation.

In one embodiment, the scan module 502 includes a first optical element 514 and a driver 516 coupled to the first optical element 514, the driver 516 being configured to drive the first optical element 514 to rotate about a rotation axis 509, such that the first optical element 514 redirects a collimated light beam 519. The first optical element 214 projects the collimated beam 219 into different directions. In one embodiment, the angle between the altered direction of the collimated beam 519 through the first optical element and the axis of rotation 509 changes as the first optical element 514 rotates. In one embodiment, the first optical element 514 includes a pair of opposing non-parallel surfaces through which the collimated light beam 519 passes. In one embodiment, the first optical element 514 includes a prism having a thickness that varies along at least one radial direction. In one embodiment, first optical element 514 comprises a wedge angle prism that refracts collimated light beam 519.

In one embodiment, the scan module 502 further comprises a second optical element 515, the second optical element 515 rotates around the rotation axis 509, and the rotation speed of the second optical element 515 is different from the rotation speed of the first optical element 514. The second optical element 515 is used to change the direction of the light beam projected by the first optical element 514. In one embodiment, the second optical element 515 is connected to another driver 517, and the driver 517 drives the second optical element 515 to rotate. The first 514 and second 515 optical elements may be driven by the same or different drives to rotate and/or steer the first 514 and second 515 optical elements differently, thereby projecting the collimated beams 519 in different directions into the ambient space, allowing a larger spatial range to be scanned. In one embodiment, the controller 518 controls the

drivers

516 and 517 to drive the first optical element 514 and the second optical element 515, respectively. The rotation speed of the first 514 and second 515 optical elements may be determined according to the area and pattern desired to be scanned in an actual application. The

drivers

516 and 517 may comprise motors or other drivers.

In one embodiment, the second optical element 515 includes a pair of opposing non-parallel surfaces through which the light beam passes. In one embodiment, the second optical element 515 includes a prism having a thickness that varies along at least one radial direction. In one embodiment, the second optical element 515 comprises a wedge angle prism.

In one embodiment, the scan module 502 further comprises a third optical element (not shown) and a driver for driving the third optical element to move. Optionally, the third optical element comprises a pair of opposed non-parallel surfaces through which the light beam passes. In one embodiment, the third optical element comprises a prism having a thickness that varies along at least one radial direction. In one embodiment, the third optical element comprises a wedge angle prism. At least two of the first, second and third optical elements rotate at different rotational speeds and/or rotational directions.

Rotation of the optical elements in the scanning module 502 may project light in different directions, such as the directions of

light

511 and 513, so as to scan the space around the distance measuring device 500. When the light 511 projected by the scanning module 502 hits the detected object 501, a part of the light is reflected by the detected object 501 to the distance measuring device 500 in the opposite direction to the projected light 511. The return light 512 reflected by the detected object 501 passes through the scanning module 502 and then enters the collimating element 504.

The detector 505 is placed on the same side of the collimating element 504 as the emitter 503, and the detector 505 is used to convert at least part of the return light passing through the collimating element 504 into an electrical signal.

In one embodiment, each optical element is coated with an antireflection coating. Optionally, the thickness of the anti-reflective coating is equal to or close to the wavelength of the light beam emitted by the emitter 503, which can increase the intensity of the transmitted light beam.

In one embodiment, a filter layer is coated on a surface of a component in the distance measuring device, which is located on the light beam propagation path, or a filter is arranged on the light beam propagation path, and is used for transmitting at least a wave band in which the light beam emitted by the emitter is located and reflecting other wave bands, so as to reduce noise brought to the receiver by ambient light.

In some embodiments, the transmitter 503 may include a laser diode through which laser pulses in the order of nanoseconds are emitted. Further, the laser pulse reception time may be determined, for example, by detecting the rising edge time and/or the falling edge time of the electrical signal pulse. In this manner, the ranging apparatus 500 can calculate TOF using the pulse reception time information and the pulse emission time information, thereby determining the distance of the object 501 to be detected from the ranging apparatus 500.

The distance and orientation detected by ranging device 500 may be used for remote sensing, obstacle avoidance, mapping, modeling, navigation, and the like. In an embodiment, the utility model provides a range unit can be applied to portable platform, and the range unit mountable is at portable platform's platform body. The movable platform with the distance measuring device can measure the external environment, for example, the distance between the movable platform and an obstacle is measured for the purpose of avoiding the obstacle, and the two-dimensional or three-dimensional mapping is carried out on the external environment. In certain embodiments, the movable platform comprises at least one of an unmanned aerial vehicle, an automobile, a remote control car, a robot, a camera. When the distance measuring device is applied to the unmanned aerial vehicle, the platform body is a fuselage of the unmanned aerial vehicle. When the distance measuring device is applied to an automobile, the platform body is the automobile body of the automobile. The vehicle may be an autonomous vehicle or a semi-autonomous vehicle, without limitation. When the distance measuring device is applied to the remote control car, the platform body is the car body of the remote control car. When the distance measuring device is applied to a robot, the platform body is the robot. When the distance measuring device is applied to a camera, the platform body is the camera itself.

The utility model discloses an above-mentioned light scanning module, range unit and movable platform make setting between the optical element compacter through the shape that changes optical element, realize obtaining higher optical characteristic with lower cost, and effectively reduce the volume of whole device, are favorable to improving the performance of whole device.

Although the example embodiments have been described herein with reference to the accompanying drawings, it is to be understood that the above-described example embodiments are merely illustrative and are not intended to limit the scope of the present invention thereto. Various changes and modifications may be effected therein by one of ordinary skill in the pertinent art without departing from the scope or spirit of the present invention. All such changes and modifications are intended to be included within the scope of the present invention as claimed in the appended claims.

It will be understood by those skilled in the art that all of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and all of the processes or elements of any method or apparatus so disclosed, may be combined in any combination, except combinations where such features are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.

Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features included in other embodiments, rather than other features, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments may be used in any combination.

The above description is only for the specific embodiments of the present invention or the description of the specific embodiments, the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. The protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A scanning module comprising at least one optical element for changing the propagation direction of a light beam emitted by a distance measuring module and at least one driver for driving a target optical element of the at least one optical element into motion, characterized in that the at least one optical element comprises a first optical element which is close to the position where the light beam enters the scanning module with respect to the other optical elements of the at least one optical element and which is adapted to collimate the light beam and to change the propagation direction of the collimated light beam.

2. The scan module of claim 1, wherein the first optical element comprises a curved surface and a first inclined surface, the curved surface is a light incident surface of the first optical element for the light beam, and the first inclined surface is a light emergent surface of the first optical element for the collimated light beam.

3. A scanning module according to claim 1 or 2, wherein at least one of the optical elements further comprises a second optical element for changing the direction of propagation of the output beam of the first optical element.

4. The scan module of claim 3, wherein the second optical element includes a pair of opposed non-parallel surfaces, the second optical element having a thickness that varies along at least one radial direction.

5. The scan module of claim 4, wherein the second optical element comprises a flat surface and a second angled surface;

6. The scan module of claim 2, wherein the curved surface comprises a spherical surface or an aspherical surface.

7. The scan module of claim 6, wherein the spherical surface comprises a convex spherical surface or a concave spherical surface.

8. A ranging apparatus, comprising:

the scanning module of any one of claims 1-7;

9. The range finder device of claim 8, wherein said range finding module comprises a transmitter for transmitting said light beam;

10. The range finder device of claim 8, wherein the range finding module comprises a transmitter and a third optical element, the transmitter for transmitting the light beam;

11. The range finder device of claim 10, wherein the third optical element comprises a pair of opposing non-parallel surfaces, the pair of surfaces of the third optical element comprising at least one curved surface.

12. The distance measuring device is characterized by further comprising an optical element, the optical element is used for collimating the light beam emitted by the distance measuring module and changing the propagation direction of the collimated light beam, and the optical element is arranged in the scanning module or the distance measuring module.

13. The distance measuring device of claim 12, wherein the optical element comprises a curved surface and an inclined surface, the curved surface is a light incident surface of the optical element for the light beam, and the inclined surface is a light emergent surface of the optical element for the collimated light beam.

14. A movable platform, comprising:

a platform body; and

a ranging apparatus as claimed in any of claims 8 to 11 or as claimed in any of claims 12 to 13 mounted on the platform body.