CN209979845U

CN209979845U - Distance measuring device and mobile platform

Info

Publication number: CN209979845U
Application number: CN201920021445.6U
Authority: CN
Inventors: 董帅; 洪小平
Original assignee: Shenzhen Dajiang Innovations Technology Co Ltd
Current assignee: Shenzhen Dajiang Innovations Technology Co Ltd
Priority date: 2019-01-07
Filing date: 2019-01-07
Publication date: 2020-01-21
Anticipated expiration: 2029-01-07

Abstract

The utility model provides a range unit and moving platform. The distance measuring device comprises an emitter, a collimation element, a detector and a convergence element, and further comprises a first pre-shaping element and/or a second pre-shaping element, wherein the first pre-shaping element is arranged on the emitting light path between the collimation element and the light emitting surface of the emitter, and the second pre-shaping element is arranged on the receiving light path of the return light between the convergence element and the light sensing surface of the detector; wherein the effective aperture of the collimating element is larger than the effective aperture of the first pre-shaping element, and the effective aperture of the converging element is larger than the effective aperture of the second pre-shaping element. The utility model discloses a scheme can realize obtaining the good optical property under heavy-calibre lens with lower cost to and can reduce optical system's aberration etc. thereby be favorable to improving range unit's performance.

Description

Distance measuring device and mobile platform

Description

Technical Field

The utility model relates to a range finding technical field generally, more specifically relates to a range unit and moving platform.

Background

The distance measuring device plays an important role in many fields, for example, the distance measuring device can be used on a mobile carrier or a non-mobile carrier, and is used for remote sensing, obstacle avoidance, mapping, modeling, environmental perception and the like. Especially, mobile carriers such as robots, manually operated airplanes, unmanned airplanes, vehicles, ships and the like can be navigated by the ranging device in a complex environment to realize path planning, obstacle detection, obstacle avoidance and the like.

The distance measuring device usually adopts a semiconductor laser as a light source, however, the semiconductor laser has large divergence angle and large difference of fast and slow axis BPP (product of light beam parameters in the directions of the slow axis and the fast axis), and light beam collimation or compression is required in many application occasions; the traditional narrow beam collimation is realized by a cylindrical lens or a cylindrical lens array close to a light emitting surface, and the wide beam collimation is realized by a single aspheric lens or a cemented spherical lens group; however, in some occasions requiring wide light beams and large apertures (greater than 30mm), the aperture of the required lens is increased due to too large spot size, which is a challenge for processing high index parameter lenses, and corresponding lens parameters can be designed in many occasions, but the processing cannot be performed or the processing cost is higher, which affects the mass production of products. And the large-aperture optical system using the large-aperture lens also has the following disadvantages: 1) the single large-aperture lens has poor optical performance and poor system performance; 2) if a plurality of large-caliber lenses are adopted, the optical system is heavy and high in cost; 3) if a large-caliber aspheric lens is adopted, the processing difficulty is high, and the cost is high.

Therefore, there is a need for an improved distance measuring device to solve the above technical problems.

SUMMERY OF THE UTILITY MODEL

The present invention has been made to solve at least one of the above problems. Specifically, an aspect of the utility model provides a distance measuring device, distance measuring device includes:

a transmitter for transmitting a sequence of light pulses;

the collimating element is positioned on a light emitting path of the emitter and is used for collimating and emitting the light pulse sequence emitted by the emitter;

a converging element for converging at least a portion of the return light reflected by the object to a detector;

the detector is used for receiving at least one part of the return light, converting the part of the return light into an electric signal and determining the distance and/or the direction of the object from the distance measuring device according to the electric signal;

the first pre-shaping element is arranged on the emitting light path between the collimation element and the light emitting surface of the emitter, and the second pre-shaping element is arranged on the receiving light path of the return light between the convergence element and the light sensing surface of the detector;

wherein the effective aperture of the collimating element is larger than the effective aperture of the first pre-shaping element, the effective aperture of the converging element is larger than the effective aperture of the second pre-shaping element, the first pre-shaping element is an aspheric lens, and the collimating element is a spherical lens.

Illustratively, the effective focal length of the collimating element is greater than or equal to 10 times the effective focal length of the first pre-shaping element, and/or the effective focal length of the converging element is greater than or equal to 10 times the effective focal length of the second pre-shaping element.

Illustratively, at least two of the optical axis of the light emitting device, the optical axis of the first pre-shaping element, and the optical axis of the collimating element are coaxial, and the distance between the light emitting surface of the light emitting device and the first pre-shaping element is smaller than the focal length of the first pre-shaping element.

Illustratively, the light exit surface of the emitter is located between the backward focus of the collimating element and the first pre-shaping element.

Exemplarily, the first optical system comprises the collimating element and the first pre-shaping element, and the light exit surface of the emitter is located at a focal plane of the first optical system;

and/or the presence of a gas in the gas,

the second optical system includes the converging element and the second pre-shaping element, and the detector includes a photosensitive surface located at a focal plane of the second optical system.

Illustratively, the emitter emits the sequence of light pulses with an effective divergence angle less than or equal to 180 × D/(π × f), where D is the effective aperture of the collimating element and f is the focal length of the first optical system.

Illustratively, the effective acceptance angle α of the detector satisfies the following formula:

α≤180×D/(π×f)，

wherein D is an effective aperture of the converging element, and f is a focal length of the second optical system.

Illustratively, the effective divergence angle of the optical pulse train emitted by the emitter is less than the effective acceptance angle of the detector.

Illustratively, the effective photosensitive size of the detector is greater than or equal to 2 times the size of the airy disk of the second optical system.

Illustratively, the effective photosensitive size of the detector is greater than or equal to 2 times the diameter of the airy disk of the second optical system.

Illustratively, the effective photosensitive size of the detector is greater than the effective luminescent size of the emitter.

Illustratively, the shape of the light-sensing surface of the detector includes a circle, an ellipse, or a rectangle.

Illustratively, the effective focal length of the first optical system ranges from 20mm to 200mm, and/or the effective focal length of the second optical system ranges from 20mm to 200 mm.

Illustratively, the light exit surface of the emitter is placed at a back focal plane of the first optical system.

Illustratively, the photosensitive surface of the detector is placed at a back focal plane of the second optical system.

Illustratively, the transmitter and the first pre-shaping element are integrally packaged; and/or

The detector and the second pre-shaping element are integrally packaged.

Exemplarily, the distance measuring apparatus further comprises:

a first encapsulant in which the emitter is embedded, the first pre-shaping element being disposed on an outer surface of the first encapsulant for compressing a sequence of optical pulses emitted by the emitter, and/or,

the detector is embedded in the second sealing body, and the second pre-shaping element is arranged on the outer surface of the second sealing body and used for converging the return light.

For example, the first sealing body and the first pre-shaping element are integrally formed, and/or the second sealing body and the second pre-shaping element are integrally formed.

Exemplarily, the distance measuring apparatus further comprises:

the base plate is used for bearing the emitter and is attached to a circuit board.

A housing disposed on a surface of the substrate, a receiving space being formed between the substrate and the housing, wherein a light transmitting region is at least partially disposed on the housing, the emitter is disposed in the receiving space, and the first pre-shaping element is disposed at the light transmitting region, and light emitted from the emitter is emitted through the first pre-shaping element.

The first pre-shaping element is fixed to the light-transmitting region by means of bonding or welding.

Exemplarily, the distance measuring device further comprises a bracket, and the first pre-shaping element is arranged on the bracket to be fixed by the bracket.

Exemplarily, the distance measuring apparatus further comprises:

and the substrate is used for bearing the detector and is attached to a circuit board.

And a housing disposed on a surface of the substrate, an accommodating space being formed between the substrate and the housing, wherein a light transmitting region is at least partially disposed on the housing, the detector is disposed in the accommodating space, the second pre-shaping element is disposed at the light transmitting region, and the return light condensed by the second pre-shaping element is incident to the detector.

The second pre-shaping element is fixed to the light-transmitting region by means of bonding or welding.

Exemplarily, the distance measuring device further comprises a bracket, and the second pre-shaping element is arranged on the bracket to be fixed by the bracket.

In an exemplary manner, the first and second electrodes are,

the second pre-shaping element comprises an aspheric lens.

Illustratively, the focal length of the first pre-shaping element ranges between 10 μm and 10mm, and/or,

the focal length range of the second pre-shaping element is between 10 mu m and 10 mm.

Illustratively, the collimating element comprises a spherical lens group, and/or,

the converging element comprises a spherical lens or a spherical lens group.

Illustratively, the effective aperture of the collimating element is above 20mm, and/or,

the effective aperture of the converging element is above 20 mm.

Illustratively, the collimating element and the converging element are the same transceiver lens.

Exemplarily, the distance measuring apparatus further comprises:

and the optical path changing element is positioned within the back focal length of the transceiving lens and used for changing a transmitting optical path of the optical pulse sequence transmitted by the transmitter or a receiving optical path of the return light passing through the transceiving lens so as to combine the transmitting optical path and the receiving optical path.

Illustratively, the optical path altering component is disposed on the same side of the transceiver lens as the emitter and the detector.

Illustratively, at least one of the detector and the transmitter is placed on a side of an optical axis of the transceiver lens.

Illustratively, the distance from the emitter to the optical path changing element is equal to the distance from the detector to the optical path changing element.

Illustratively, the optical path altering element is offset from an optical axis of the transceiver lens for projecting the optical pulse train emitted by the emitter towards an edge field of view of the transceiver lens.

Illustratively, the optical path changing element includes a mirror and/or a prism.

Illustratively, the mirror includes at least one of a flat mirror and a concave mirror.

Illustratively, the optical path changing element includes a mirror provided with a light transmitting region, wherein at least a part of one of the light pulse train emitted by the emitter and the return light reflected by the object is transmitted through the light transmitting region, and at least a part of the other light is reflected by an edge of the mirror.

Illustratively, the light-transmitting region includes an opening provided on the mirror, or the light-transmitting region includes an antireflection film provided on the mirror.

Illustratively, the optical path changing element includes a mirror, wherein at least a part of one of the light pulse train emitted by the emitter and the return light reflected by the object is transmitted from outside an edge of the mirror, and at least a part of the other light is reflected by the mirror.

Illustratively, at least a part of the light pulse train emitted by the emitter is transmitted through the light-transmitting region, wherein the area of a spot of the light pulse train irradiated on the optical path changing element is larger than or equal to the area of the light-transmitting region.

Illustratively, at least a portion of the sequence of light pulses emitted by the emitter is reflected by the mirror to the transceiver lens, and at least a portion of the return light reflected by the object is projected from outside an edge of the mirror to the detector.

Illustratively, the probe includes:

the receiving circuit is used for converting the received return light reflected by the object into an electric signal and outputting the electric signal;

a sampling circuit for sampling the electrical signal output by the receiving circuit to measure a time difference between transmission and reception of the optical pulse train;

and the arithmetic circuit is used for receiving the time difference output by the sampling circuit and calculating to obtain a distance measurement result.

Exemplarily, the distance measuring apparatus further comprises:

and the scanning module is used for sequentially changing the propagation paths of the light pulse sequences collimated by the collimating element to different directions for emission to form a scanning view field.

Illustratively, the ranging device comprises a lidar.

The utility model discloses another aspect provides a mobile platform, mobile platform includes:

the aforementioned distance measuring device; and

the platform body, range unit installs on the platform body.

Illustratively, the mobile platform comprises a drone, a robot, a vehicle, or a boat.

The distance measuring device provided by the embodiment of the utility model comprises a first pre-shaping element and/or a second pre-shaping element, wherein the first pre-shaping element is arranged on the transmitting light path between the collimating element and the light emitting surface of the transmitter, and the second pre-shaping element is arranged on the receiving light path of the return light between the converging element and the light sensing surface of the detector; wherein the effective aperture of the collimating element is larger than the effective aperture of the first pre-shaping element, and the effective aperture of the converging element is larger than the effective aperture of the second pre-shaping element. The light pulse sequence transmitted by the transmitter is firstly subjected to primary collimation and/or compression through the first pre-shaping element, so that the energy utilization rate of the transmitter is increased, and then the light pulse sequence is subjected to secondary collimation and/or compression through matching with the collimation element with a large caliber, so that the collimation characteristic of the light pulse sequence transmitted by the transmitter is obviously improved, and the energy utilization rate of the transmitter is increased; the return light is converged by the converging element on the receiving light path of the return light, and then the return light is converged again by the second pre-shaping element, so that the receiving rate of the return light is improved, and the signal-to-noise ratio of the distance measuring device is favorably improved. In addition, the effective caliber of the converging element is large, so that more return light reflected by an object can be received, and the distance measuring device can be used for detecting more distant and/or weaker signals.

To sum up, the utility model discloses range unit makes up the optical system of beam collimation with collimation element and/or convergent element in advance of small-bore diameter, can realize obtaining the good optical performance under heavy-calibre lens with lower cost to and can reduce optical system's aberration etc. thereby be favorable to improving range unit's performance.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive effort.

Fig. 1 shows a schematic block diagram of a distance measuring device in an embodiment of the invention;

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

fig. 3 shows a schematic diagram of a ranging module included in the ranging device according to an embodiment of the present invention;

FIG. 4 is a schematic diagram showing the positional relationship of the main elements on the emission path of the ranging module in FIG. 3;

fig. 5 shows a schematic view of a ranging module comprised by the ranging device in another embodiment of the present invention;

fig. 6 shows a schematic view of a ranging module included in a ranging apparatus according to yet another embodiment of the present invention;

fig. 7 shows a schematic diagram of a distance measuring module included in a distance measuring device according to another embodiment of the present invention.

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.

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the present invention.

It is to be understood that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of the associated listed items.

In order to thoroughly understand the present invention, a detailed structure will be provided in the following description in order to explain the technical solution provided by the present invention. Alternative embodiments of the invention are described in detail below, however, other embodiments of the invention are possible in addition to these detailed descriptions.

In order to solve the above problem, the utility model provides a distance measuring device, distance measuring device includes:

a transmitter for transmitting a sequence of light pulses;

the collimating element is positioned on a light emitting path of the emitter and used for collimating the light pulse sequence emitted by the emitter and then emitting the light pulse sequence from the distance measuring device;

wherein the effective aperture of the collimating element is larger than the effective aperture of the first pre-shaping element, and the effective aperture of the converging element is larger than the effective aperture of the second pre-shaping element.

It is worth mentioning that the effective aperture of each element (e.g. collimating element, pre-shaping element, etc.) in this context refers to the portion of the aperture that each element actually receives the light beam.

The utility model discloses range unit makes up the optical system of beam collimation with the collimation component and/or the convergent component in advance of small bore diameter, can realize obtaining the good optical performance under heavy-calibre lens with lower cost to and can reduce optical system's aberration etc. thereby be favorable to improving range unit's performance.

The following describes the ranging device and the mobile platform in detail with reference to the accompanying drawings. The features of the following examples and embodiments may be combined with each other without conflict.

The embodiment of the utility model provides an in range unit can be electronic equipment such as laser radar, laser rangefinder. In one embodiment, the distance measuring device is used for sensing external environment information, and the data recorded in the form of points scanned by the external environment may be referred to as point cloud data, and each point in the point cloud data includes coordinates of a three-dimensional point and characteristic information of the corresponding three-dimensional point, such as distance information, orientation information, reflection intensity information, speed information, and the like of an environmental 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 100 shown in fig. 1.

As shown in fig. 1, the ranging apparatus 100 may include a transmitting circuit 110, a receiving circuit 120, a sampling circuit 130, and an operation circuit 140.

The transmit circuitry 110 may transmit a sequence of light pulses (e.g., a sequence of laser pulses). The receiving circuit 120 may receive the optical pulse train reflected by the detected object, perform photoelectric conversion on the optical pulse train to obtain an electrical signal, process the electrical signal, and output the electrical signal to the sampling circuit 130. The sampling circuit 130 may sample the electrical signal to obtain a sampling result. The arithmetic circuit 140 may determine the distance between the distance measuring device 100 and the detected object based on the sampling result of the sampling circuit 130.

Optionally, the distance measuring apparatus 100 may further include a control circuit 150, and the control circuit 150 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. 1 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 transmitting chip, and the chip dies (die) of the laser transmitting 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. 1, the distance measuring apparatus 100 may further include a scanning module for changing the propagation direction of at least one light pulse sequence emitted from the emitting circuit.

Here, a module including the transmission circuit 110, the reception circuit 120, the sampling circuit 130, and the operation circuit 140, or a module including the transmission circuit 110, the reception circuit 120, the sampling circuit 130, the operation circuit 140, and the control circuit 150 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 is emitted by the scanning module after the propagation direction is changed, and the laser pulse sequence reflected by the detector is emitted to 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. 2 shows a schematic diagram of an embodiment of the distance measuring device of the present invention using a coaxial light path.

The ranging apparatus 200 comprises a ranging module 210, the ranging module 210 comprising an emitter 203 (which may comprise the transmitting circuitry described above), a collimating element 204, a detector 205 (which may comprise the receiving circuitry, sampling circuitry and arithmetic circuitry described above) and a path-altering element 206. The distance measuring module 210 is configured to emit a light beam, receive return light, and convert the return light into an electrical signal. Wherein the emitter 203 may be configured to emit a sequence of light pulses. In one embodiment, the transmitter 203 may emit a sequence of laser pulses. Optionally, the laser beam emitted by the emitter 203 is a narrow bandwidth beam having a wavelength outside the visible range.

The collimating element 204 is disposed on an emitting light path of the emitter, and is configured to collimate the light beam emitted from the emitter 203, and collimate the light beam emitted from the emitter 203 into parallel light to be emitted to the scanning module. In the on-axis optical path, the collimating element is also used to condense at least a portion of the return light reflected by the probe. The collimating element 204 may be a collimating lens or other element capable of collimating a light beam.

In the embodiment shown in fig. 2, the transmitting optical path and the receiving optical path in the distance measuring device are combined by the optical path changing element 206 before the collimating element 204, so that the transmitting optical path and the receiving optical path can share the same collimating element, for example, share the same transceiver lens, and the optical path is more compact. For example, the optical path changing element is located within the back focal length of the collimating element 204, and is used to change the transmitting optical path of the optical pulse train transmitted by the transmitter or the receiving optical path of the return light passing through the collimating element 204, so that the transmitting optical path and the receiving optical path are combined. Optionally, the optical path changing element 206 comprises a mirror and/or a prism. The reflecting mirror comprises at least one of a plane reflecting mirror and a concave reflecting mirror.

In other implementations, it is also possible to use respective collimating elements for the emitter 203 and the detector 205, for example, the emitter 203 uses a collimating element, and the detector uses a converging element with a converging function, and the optical path changing element 206 is disposed on the optical path after the collimating element.

In the embodiment shown in fig. 2, since the beam aperture of the light beam emitted from the emitter 203 is small and the beam aperture of the return light received by the distance measuring device is large, the optical path changing element can adopt a small-area mirror to combine the emission optical path and the reception optical path. In other implementations, the optical path changing element may also be a mirror with a through hole, wherein the through hole is used for transmitting the outgoing light from the emitter 203, and the mirror is used for reflecting the return light to the detector 205. 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. 2, the optical path altering element is offset from the optical axis of the collimating element 204 for projecting the optical pulse train emitted by the emitter towards the peripheral field of view of the transceiver lens. In other implementations, the optical path altering element may also be located on the optical axis of the collimating element 204.

The ranging device 200 also includes a scanning module 202. The scanning module 202 is disposed on the emitting light path of the distance measuring module 210, and the scanning module 202 is configured to change the transmission direction of the collimated light beam 219 emitted by the collimating element 204, project the collimated light beam to the external environment, and project the return light beam to the collimating element 204. The return light is converged by the collimating element 204 onto the detector 205.

In one embodiment, the scanning module 202 may include at least one optical element for altering the propagation path of the light beam, wherein the optical element may alter the propagation path of the light beam by reflecting, refracting, diffracting, etc., the light beam. For example, the scanning module 202 includes 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, multiple optical elements of the scanning module 202 may rotate or oscillate about a common axis 209, with each rotating or oscillating optical element serving to constantly change the direction of propagation of an incident beam. In one embodiment, the multiple optical elements of the scanning module 202 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 202 may rotate at substantially the same rotational speed. In some embodiments, the multiple optical elements of the scanning module may also be rotated about different axes. In some embodiments, the multiple optical elements of the scanning module may also rotate in the same direction, or in different directions; or in the same direction, or in different directions, without limitation.

In one embodiment, the scanning module 202 includes a first optical element 214 and a driver 216 coupled to the first optical element 214, the driver 216 configured to drive the first optical element 214 to rotate about the rotation axis 209, such that the first optical element 214 redirects the collimated light beam 219. The first optical element 214 projects the collimated beam 219 into different directions. In one embodiment, the angle between the direction of the collimated beam 219 after it is altered by the first optical element and the axis of rotation 209 changes as the first optical element 214 is rotated. In one embodiment, the first optical element 214 includes a pair of opposing non-parallel surfaces through which the collimated light beam 219 passes. In one embodiment, the first optical element 214 includes a prism having a thickness that varies along at least one radial direction. In one embodiment, the first optical element 214 comprises a wedge angle prism that refracts the collimated beam 219.

In one embodiment, the scanning module 202 further comprises a second optical element 215, the second optical element 215 rotating around a rotation axis 209, the rotation speed of the second optical element 215 being different from the rotation speed of the first optical element 214. The second optical element 215 is used to change the direction of the light beam projected by the first optical element 214. In one embodiment, the second optical element 215 is coupled to another driver 217, and the driver 217 drives the second optical element 215 to rotate. The first optical element 214 and the second optical element 215 may be driven by the same or different drivers, such that the first optical element 214 and the second optical element 215 rotate at different speeds and/or turns, thereby projecting the collimated light beam 219 into different directions in the ambient space, which may scan a larger spatial range. In one embodiment, the controller 218 controls the

drivers

216 and 217 to drive the first optical element 214 and the second optical element 215, respectively. The rotation speed of the first optical element 214 and the second optical element 215 can be determined according to the region and the pattern expected to be scanned in the actual application. The

drives

216 and 217 may include motors or other drives.

In one embodiment, second optical element 215 includes a pair of opposing non-parallel surfaces through which the light beam passes. In one embodiment, second optical element 215 includes a prism having a thickness that varies along at least one radial direction. In one embodiment, second optical element 215 comprises a wedge angle prism.

In one embodiment, the scan module 202 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 202 may project light in different directions, such as the direction of the projected light 211 and the direction 213, thus scanning the space around the ranging device 200. When the light 211 projected by the scanning module 202 hits the detection object 201, a part of the light is reflected by the detection object 201 to the distance measuring device 200 in the opposite direction to the projected light 211. The return light 212 reflected by the object 201 passes through the scanning module 202 and then enters the collimating element 204.

The detector 205 is placed on the same side of the collimating element 204 as the emitter 203, and the detector 205 is used to convert at least part of the return light passing through the collimating element 204 into an electrical signal. In some embodiments, the detector 105 may include an avalanche photodiode, which is a high sensitivity semiconductor device capable of converting an optical signal into an electrical signal using a photocurrent effect.

In one embodiment, each optical element is coated with an antireflection coating. Optionally, the thickness of the antireflection film is equal to or close to the wavelength of the light beam emitted by the emitter 203, 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 203 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 200 may calculate TOF using the pulse reception time information and the pulse emission time information, thereby determining the distance of the probe 201 to the ranging apparatus 200.

The distance measuring module further comprises a first pre-shaping element and/or a second pre-shaping element, such as a pre-collimating lens, and the distance measuring module comprising the pre-shaping element is described below with reference to fig. 3 to 7, wherein the technical features in these embodiments are also applicable to the distance measuring module shown in fig. 2 without conflict.

In some embodiments, the optical path changing element 206 is located within the back focal length of the collimating element 204, and is used to change the receiving optical path of the return light passing through the collimating element 204, so as to combine the transmitting optical path and the receiving optical path, for example, in the embodiment shown in fig. 3, the transmitting optical path of the optical pulse sequence transmitted by the transmitter 203 is incident to the collimating element 204 through the optical path changing element 206, and the receiving optical path of the return light converged by the collimating element 204 is received by the detector 205 after being changed by the optical path changing element; in other embodiments, the optical path changing element 206 is located within the back focal length of the collimating element 204 for changing the emission optical path of the optical pulse train emitted by the emitter, for example, as shown in fig. 5, the optical pulse train emitted by the emitter 203 is incident on the collimating element 204 through the optical path changing element 206, and at least a part of the return light converged by the collimating element 204 is received by the detector 205 through the outer edge of the optical path changing element 206.

It is worth mentioning that in this context, the back focus (also called back focus) refers to the focus on the side of the optical element or optical system (e.g. collimating element, converging element, pre-shaping element) close to the emitter or close to the detector, the back focus (also called back focus) refers to the distance between the vertex of the back surface of the optical element or optical system and the back focus, the front focus (also called front focus) refers to the focus on the side of the optical element (e.g. collimating element, converging element, pre-shaping element) away from the emitter or away from the detector, and the front focus (also called front focus) refers to the distance between the vertex of the front surface of the optical element or optical system and the front focus.

In some embodiments, the optical path altering component 206 is placed on the same side of the collimating component 204 as the emitter 203 and the detector 205, and the collimating component 204 comprises a transceiver lens. In one example, at least one of the optical path changing element 206, the detector 205 and the emitter 203 is placed on one side of the optical axis of the collimating element 204. For example, in the embodiment shown in fig. 3, the emitter 203 is disposed on the optical axis of the collimating element 204, and the detector 205 is disposed on one side of the optical axis of the collimating element 204, or, in the embodiment shown in fig. 5, the detector 205 is disposed on the optical axis of the collimating element 204, and the emitter 203 is disposed on one side of the optical axis of the collimating element 204, further, the central axis of the light pulse train emitted by the emitter 203 and the central axis of the return light received by the detector may be substantially 90 °. The reflecting surface of the optical path changing element 206 is at 45 ° to the central axis of the optical pulse train emitted by the emitter 203 and at 45 ° to the central axis of the return light received by the detector. The above is merely an example, and is not limited to this example. In other embodiments, the detector 205, emitter 203, and optical path altering component 206 may be positioned at other angles. For another example, in the embodiment shown in fig. 6, the detector 205 and the emitter 203 are both placed on one side of the optical axis of the collimating element 204.

In one embodiment, as shown in fig. 6, the optical path changing element 206 is offset from the optical axis of the collimating element 204, and is configured to project the optical pulse train emitted by the emitter 203 toward the fringe field of view of the collimating element 204, so as to minimize the blocking of the optical path of the return light by the optical path changing element 206, so that more return light is received by the detector, and thus, a longer distance or a weaker signal detection is achieved.

In some embodiments, the optical path changing element comprises a mirror, wherein at least a part of one of the light pulse sequence emitted by the emitter and the return light reflected by the object is transmitted from the outside of the edge of the mirror, and at least a part of the other light is reflected by the mirror, for example, in the embodiment shown in fig. 5, since the beam aperture of the light beam emitted by the emitter 203 is small and the beam aperture of the return light received by the distance measuring device is large, the optical path changing element may adopt a mirror with a small area to combine the emission optical path and the reception optical path, reflect at least a part of the light pulse sequence emitted by the emitter 203 to the collimating element 204 via the mirror, and project at least a part of the return light reflected by the object to the detector 205 from the outside of the edge of the mirror.

In some other implementations, the optical path changing element includes a mirror provided with a light-transmitting area, wherein at least a part of one of the light pulse sequence emitted by the emitter and the return light reflected by the object is transmitted through the light-transmitting area, and at least a part of the other light is reflected by an edge of the mirror, and the light-transmitting area includes an opening provided on the mirror, for example, as shown in fig. 3 and 6, the optical path changing element 206 may also be a mirror with an opening for transmitting at least a part of the light pulse sequence emitted by the emitter 203, and a mirror for reflecting at least a part of the return light to the detector 205. 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. Optionally, the light-transmitting region includes an antireflection film disposed on the reflector, which can increase the intensity of the transmitted light beam, for example, the central region of the reflector is a light-transmitting region made of a light-transmitting material, the light-transmitting material is coated with an antireflection film, and the edge of the reflector is coated with a high-reflection film, so as to reflect the light pulse train or the return light emitted by the emitter.

In one example, as shown in fig. 3, at least a portion of the optical pulse train emitted by the emitter 203 transmits through the transparent region, wherein the area of a light spot irradiated by the optical pulse train on the optical path changing element 206 is greater than or equal to the area of the transparent region, and when the area of the light spot is greater than the area of the transparent region, a portion of the optical pulse train is blocked and cannot be used for detection.

In some other implementations, the emitter 203 and the detector 205 may use respective collimating elements, for example, as shown in fig. 7, the emitter 203 uses a collimating element 204, the collimating element 204 is located on the emitting optical path of the emitter 203 and is used for collimating and emitting the optical pulse train emitted by the emitter 203, the detector 205 uses a converging element 2041 with a converging function, the converging element 2041 is used for converging at least a part of the return light reflected by the object to the detector 205, and the optical path changing element 206 is disposed on the optical path after the collimating element.

In the embodiment of the transmit-receive coaxial system shown in fig. 7, the distance measuring module 210 includes a transmitting module 2101 and a receiving module 2102, and the distance measuring module 210 further includes a first pre-shaping element 2032 and/or a second pre-shaping element 2052, where the first pre-shaping element 2032 is disposed on a transmitting optical path between the collimating element 204 and an optical emergent surface of the transmitter 203, and the second pre-shaping element 2052 is disposed on a receiving optical path of the return light between the converging element 2041 and an optical sensitive surface of the detector 205; the effective aperture of the collimating element 204 is larger than the effective aperture of the first pre-shaping element 2032, and the effective aperture of the converging element 2041 is larger than the effective aperture of the second pre-shaping element 2052. Alternatively, the first pre-shaping element may be disposed only on the transmission optical path, or the second pre-shaping element may be disposed only on the reception optical path, or the first pre-shaping element 2032 and the second pre-shaping element 2052 may be disposed on the transmission optical path and the reception optical path, respectively.

The light pulse sequence emitted by the emitter 203 is firstly subjected to primary collimation and/or compression by the first pre-shaping element 2032, so that the energy utilization rate of the emitter is increased, and then the light pulse sequence is subjected to secondary collimation and/or compression by matching with a collimation element with a large caliber, so that the collimation characteristic of the light pulse sequence emitted by the emitter is obviously improved; on the receiving light path of the return light, the return light is converged by a converging element (or a collimating element in a transceiving coaxial light path) and then converged again by a second pre-shaping element, so that the receiving rate of the return light is improved, and the signal-to-noise ratio of the distance measuring device is favorably improved. In addition, the effective caliber of the converging element is large, so that more return light reflected by an object can be received, and the distance measuring device can be used for detecting more distant and/or weaker signals.

The effective focal length of the collimating element 204 is greater than the effective focal length of the first pre-shaping element 2032, for example, the effective focal length of the collimating element 204 is greater than or equal to 10 times the effective focal length of the first pre-shaping element 2032, and further, the back focal length of the collimating element 204 is greater than or equal to 10 times the front focal length of the first pre-shaping element 2032. In one example, the effective focal length of the converging element 2041 is greater than the effective focal length of the second pre-shaping element 2052, for example, the effective focal length of the converging element 2041 is greater than or equal to 10 times the effective focal length of the second pre-shaping element 2052, further, as shown in fig. 7, the backward focal length of the converging element 2041 is greater than or equal to 10 times the forward focal length of the second pre-shaping element 2052, or, as shown in fig. 3, the transmitting optical path and the receiving optical path may share the same collimating element 204, and the backward focal length of the collimating element 204 is greater than or equal to 10 times the forward focal length of the second pre-shaping element 2052. The above numerical ranges are only examples, and other suitable numerical ranges may be applicable to the embodiments of the present invention.

The first pre-shaping element and the second pre-shaping element may comprise short focal length lenses, for example, the focal length of the first pre-shaping element may be in the range of 10 μm to 10mm, and/or the focal length of the second pre-shaping element may be in the range of 10 μm to 10mm, or other suitable focal length ranges, which may also be applied to the configurations shown in fig. 3 to 6. Optionally, as shown in fig. 7, the effective focal length of the first optical system ranges from 20mm to 200mm, and/or the effective focal length of the second optical system ranges from 20mm to 200 mm. The above numerical ranges are only examples, and other suitable range values may be equally applied to the embodiments of the present invention,

in an optical system comprising a plurality of lenses, the effective focal length is generally the distance from the main plane of the system to the corresponding front and back focal points, and in an optical system, the system focal length is usually expressed as the effective focal length, and the front focal length of the optical system is the distance from the focal point in front of the system to the vertex of the first optical surface. The back focal length is the distance from the vertex of the last optical surface of the system to the back focal point.

Optionally, the first pre-shaping element 2032 comprises an aspheric lens and the second pre-shaping element 2052 comprises an aspheric lens. The first pre-shaping element 2032 and the second pre-shaping element 2052 may use the same lens or different lenses, and the first pre-shaping element 2032 and the second pre-shaping element 2052 may also be other types of lenses, such as a cylindrical lens, a spherical lens group, or a combination of these lenses.

The aforementioned distance measurement modules 210 each include a first pre-shaping element 2032 and/or a second pre-shaping element 2052, and the positional relationships between the elements are described with reference to fig. 3 and 4, but it is understood that the positional relationships are also applicable to distance measurement modules of other structural types in the embodiments of the present invention.

In the coaxial transceiving embodiment shown in fig. 3, the ranging module 210 shares the same collimating element, and combines the transmitting optical path and the receiving optical path in the ranging apparatus before the collimating element 204 through the optical path changing element 206, so that the transmitting optical path and the receiving optical path can share the same collimating element 204, for example, share a transceiving lens, and the optical path is more compact.

Exemplarily, as shown in fig. 3, the first optical system includes the collimating element 204 and the first pre-shaping element 2032, the light emitting surface of the emitter 203 is located between the backward focal point of the collimating element 204 and the first pre-shaping element 2032, for example, the light emitting surface of the emitter 203 is located at the focal plane of the first optical system, for example, the light emitting surface of the emitter 203 is located at the back focal plane of the first optical system, and particularly, the light emitting surface of the emitter is located at the back focal plane of the first optical system, and the "focal plane" in this document refers to a plane that passes through the focal point of the corresponding optical system and is perpendicular to the optical axis of the optical system, wherein the light emitting surface of the emitter is located at the focal plane of the first optical system, which has a better collimating effect on the light pulse sequence emitted by the emitter.

In the embodiment shown in fig. 7, the second optical system includes the converging element 2041 and the second pre-shaping element 2052, or, in the embodiment shown in fig. 3, the second optical system includes the collimating element 204 and the second pre-shaping element 2052, and the detector includes a photosensitive surface, which is located at a focal plane of the second optical system, for example, the photosensitive surface of the detector 205 is located at a back focal point of the second optical system, and particularly, the photosensitive surface of the detector 205 is located at a back focal plane of the second optical system, so as to achieve a relatively better converging effect and improve the detection accuracy of the detector.

The distance of the emitter 203 from the optical path changing element 206 is not necessarily equal to the distance of the detector 205 from the optical path changing element 206. As shown in fig. 3, when the focal length of the first optical system is equal to the focal length of the second optical system, the emitter 203 is placed on the back focal plane of the first optical system, and when the first pre-shaping element 2032 and the second pre-shaping element 2052 are substantially the same element, since the distance from the emitter 203 to the optical path changing element 206 is equal to the distance from the detector 205 to the optical path changing element 206, the detector is placed on the back focal plane of the second optical system, and the converging effect on the return light is better here.

Specifically, the positional relationship among the emitter, the first pre-shaping element, and the collimating element, and the detector, the second pre-shaping element, and the collimating element (or the converging element) in the optical system are explained and explained with reference to fig. 4, although only a part of the elements on the transmission optical path in fig. 3 is shown in fig. 4, it is understood that the following positional relationship is equally applicable to the corresponding elements on the reception optical path, and is also equally applicable to other embodiments, in which the forward focal point 11 of the first pre-shaping element 2032, the backward focal point 12 of the first optical system including the collimating element 204 and the first pre-shaping element 2032, the backward focal point 13 of the collimating element 204, the backward focal point of the corresponding collimating element 204 is f1, the distance between the forward focal point 11 of the first pre-shaping element 2032 and the backward focal point 13 of the collimating element 203204 is Δ, Δ is greater than f2, f1 is greater than f2, the distance between the light emitting surface of the emitter 203 and the first pre-shaping element 2032 is L, the forward focal length f2 of the first pre-shaping element 2032, and the center distance d between the collimating element 204 and the first pre-shaping element 2032.

For example, at least two of the outgoing optical axis of the emitter 203 (i.e. the central axis of the light pulse train emitted by the emitter), the optical axis of the first pre-shaping element 2032, and the optical axis of the collimating element 204 are coaxial, and the distance between the outgoing surface of the emitter 203 and the first pre-shaping element 2032 is smaller than the focal length of the first pre-shaping lens 2032, in particular, smaller than the forward focal length of the first pre-shaping element 2032, for example, the distance L between the outgoing surface of the emitter 203 and the first pre-shaping element 2032 satisfies the following formula:

similarly, the distance between the photosensitive surface of the detector 205 and the second pre-shaping element 2052 in fig. 3 can be calculated by the above formula, since in fig. 3, the detector 205 is located at one side of the optical axis of the collimating element 204 and can be rotated around the intersection point of the central axis of the receiving optical path and the central axis of the transmitting optical path in the direction of the transmitter, so that the central axis of the receiving optical path coincides with the central axis of the transmitting optical path, and the equivalent calculation is performed by replacing Δ by the distance between the forward focal point of the second pre-shaping element and the backward focal point of the collimating element 204 on the optical axis of the collimating element, wherein the distance is larger than the forward focal length of the second pre-shaping element, and replacing f2 by the forward focal length of the second pre-shaping element, the receiving optical axis of the detector 205 (i.e. the central axis of the return light reflected by the object received by the detector), the optical axis of the second pre, At least two of the optical axes of the collimating elements 204 are coaxial, and the distance between the photosensitive surface of the detector 205 and the second pre-shaping element 2052 is smaller than the focal length of the second pre-shaping element 2052, and particularly, smaller than the forward focal length of the second pre-shaping element 2052.

The focal length f (or effective focal length) of the first optical system satisfies the following formula:

in the formula, the distances are both positive, and the focal length f of the entire first optical system is adjusted, on the premise that f1 and f2 are known, when the distance d between the first pre-shaping element 2032 and the collimating element 204 is adjusted, the focal length f of the entire optical system is also changed correspondingly, where d is decreased, f is increased, d is increased, and f is decreased. Therefore, the size of the focal length f of the optical system depends on the size of the distance d between the pre-shaping element and the collimating element, and likewise the size of the distance d depends on the focal length f of the optical system, so as to limit the central distance d between the first pre-shaping element 2032 and the collimating element 204.

Similarly, the focal length f of the second optical system can be calculated by the above formula, the central distance d between the second pre-shaping element and the collimating element is also equivalent to the distance on the optical axis of the collimating element, and then the focal length f2 in the forward direction of the second pre-shaping element 2052 and the focal length f1 in the backward direction of the collimating element 204 are substituted into the above formula to calculate the focal length f of the second optical system.

Continuing with fig. 4, the effective divergence angle β of the optical pulse train emitted by the emitter 203 satisfies the following equation:

β≤180×D/(π×f)

where D is the effective aperture of the collimating element, and f is the focal length of the first optical system, where the effective divergence angle refers to the divergence angle of the optical pulse train actually incident on the collimating element. For example, since an optical element such as the optical path changing element 206 is provided at the collimating element, the optical path changing element 206 can only make a part of the optical pulse train incident on the collimating element 204.

It is worth mentioning that the effective aperture in this context refers to the maximum aperture that the corresponding optical element (e.g. collimating element, converging element, pre-shaping element) actually uses to collimate the optical pulse train emitted by the emitter and the return light received by the detector.

In one example, as shown in fig. 3, 5-7, the effective divergence angle of the light pulse train emitted by the emitter 203 is less than the effective acceptance angle of the detector 205, so that the detector 205 can receive more return light.

The effective photosensitive size of the detector 205 is greater than or equal to 2 times the size of the airy disk of the second optical system, for example, the effective photosensitive size of the detector is greater than or equal to 2 times the diameter D1 of the airy disk of the second optical system, and the diameter D1 of the airy disk can be obtained by the following formula:

wherein D is the effective aperture of the second optical system, f is the effective focal length of the second optical system, and λ is the wavelength of the optical pulse train emitted by the emitter.

Airy disk is a spot of light that forms at the focus due to diffraction when a point source is imaged through an ideal lens. The central bright spot is a bright circular spot, a group of weak light and dark concentric annular stripes are arranged around the bright spot, the central bright spot with the first dark ring as a boundary is called an Airy spot, and the effective photosensitive size of the detector 205 is greater than or equal to 2 times of the size of the Airy spot of the second optical system, so that the detector 205 can receive more light besides the Airy spot formed on the photosensitive surface by the return light, and the photosensitive performance of the detector can be improved.

Optionally, the effective photosensitive size of the detector 205 is larger than the effective emitting size of the emitter 203, where the effective photosensitive size refers to a size, such as an area, of a photosensitive surface actually used by the detector 205 for photosensitive, and the effective emitting size refers to a size, such as an area, of an emitting surface actually used by the emitter for emitting the laser pulse sequence.

The shape of the photosensitive surface of the detector 205 includes a circle, an ellipse, or a rectangle, or other suitable shapes, and is not limited in this regard.

In the embodiment shown in fig. 3, 5-7, the transmitter 203 and the first pre-shaping element 2032 are integrally packaged; and/or, the detector 205 and the second pre-shaping element 2052 are integrally packaged, and the emitter and the detection are packaged together with the respective pre-shaping elements corresponding to the emitter and the detection through a mature packaging process, so that the integration is higher, the production difficulty is reduced, and the mass production is facilitated.

In some embodiments, as shown in fig. 3 and fig. 5 to fig. 7, the distance measuring device further includes a substrate (not shown) for carrying the emitter 203, and a housing 2031, the substrate (not shown) is for being attached to a circuit board, the housing 2031 is disposed on a surface of the substrate or the circuit board to form a receiving space between the substrate and the housing, wherein a light-transmitting region is at least partially disposed on the housing, the emitter 203 is disposed in the receiving space, the first pre-shaping element 2032 is disposed at the light-transmitting region, and light emitted from the emitter 203 is emitted through the first pre-shaping element 2032. Optionally, the first pre-shaping element 2032 is fixed at the light transmissive region by form-seal bonding or welding, or other suitable means.

Similarly, the probe and the second pre-shaping element can be packaged in the above manner, and the distance measuring device further includes a substrate (not shown) for carrying the probe 205, and a housing 2051, wherein the substrate (not shown) is used for being attached to a circuit board, the housing 2051 is disposed on the surface of the substrate or the circuit board to form a receiving space between the substrate and the housing, wherein a light-transmitting area is at least partially disposed on the housing, the probe 205 is disposed in the receiving space, and the second pre-shaping element 2052 is disposed at the light-transmitting area, and light emitted from the probe 205 is emitted through the second pre-shaping element 2052. Optionally, the second pre-shaping element 2052 is fixed at the light transmitting area by form-seal bonding or welding, or other suitable means.

In another embodiment, the ranging apparatus further comprises a bracket (not shown) on which the first pre-shaping element 2032 is disposed to be fixed by the bracket. Likewise, the distance measuring device further comprises a holder (not shown) on which the second pre-shaping element is arranged to be fixed by the holder.

In a further embodiment, the distance measuring device further comprises a sealing body (not shown), the transmitter 203 being embedded in the sealing body, and a first pre-shaping element being arranged on an outer surface of the sealing body for performing a preliminary compression of the light pulse train emitted by the transmitter. The first pre-shaping element may be provided on an outer surface of the sealing body by bonding or welding, or the sealing body and the first pre-shaping element may be integrally formed. Likewise, the probe and the second pre-shaping element may also be integrally encapsulated in the above manner, and the distance measuring device further comprises a sealing body (not shown), in which the probe 205 is embedded, and the second pre-shaping element is disposed on an outer surface of the sealing body for preliminarily compressing the optical pulse train emitted by the emitter. The second pre-shaping element may be provided on an outer surface of the sealing body by bonding or welding, or the sealing body and the second pre-shaping element may be integrally molded.

The description to the distance measuring device of the embodiment of the utility model has been accomplished so far, can also include other parts and structure to complete distance measuring device, and no longer give unnecessary details here.

To sum up, the utility model discloses range unit constitutes optical system with the collimation component (or the convergent component) of heavy-calibre and the shaping component in advance of small-calibre, this optical system can carry out the equivalence and be a big aspheric lens, can realize obtaining the good optical performance under the large-calibre lens with lower cost, reduce optical system's aberration etc. thereby be favorable to improving for example laser radar's range unit's performance, wherein carry out preliminary collimation through shaping component (for example the collimating lens in advance) to the optical pulse train of transmission, and converge the compression once more to the return light that reflects through the object, can increase the energy utilization of transmitter (for example laser), and improve transmitter end optical pulse train collimation characteristic, it is more efficient to the receipt of return light simultaneously, be favorable to improving the signal-to-noise ratio of system. In addition, the laser/detector can be packaged together by a mature packaging process, so that the integration is higher, the production difficulty is reduced, and the large-scale mass production is facilitated. Therefore, compare the conventional system of other small-bore lenses and heavy-calibre lens, the utility model discloses the scheme of embodiment has overcome that conventional system structure is complicated, the problem that the production degree of difficulty is big.

The distance and orientation detected by ranging device 200 may be used for remote sensing, obstacle avoidance, mapping, modeling, navigation, and the like. In an embodiment, the utility model discloses embodiment's range unit can be applied to moving platform, and range unit can install at moving platform's platform body. The mobile platform with the distance measuring device can measure the external environment, for example, the distance between the mobile platform and an obstacle is measured for the purpose of avoiding the obstacle, and the external environment is mapped in two dimensions or three dimensions. In certain embodiments, the mobile platform comprises at least one of an unmanned aerial vehicle, an automobile, a remote control car, a robot, a camera, a boat. 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.

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.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described device embodiments are merely illustrative, and for example, the division of the units is only one logical functional division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another device, or some features may be omitted, or not executed.

In the description provided herein, numerous specific details are set forth. It is understood, however, that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Similarly, it should be appreciated that in the description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. However, the method of the present invention should not be interpreted as reflecting an intention that: rather, the invention as claimed requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

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.

Various component embodiments of the invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art will appreciate that a microprocessor or Digital Signal Processor (DSP) may be used in practice to implement some or all of the functionality of some of the modules according to embodiments of the invention. The present invention may also be embodied as apparatus programs (e.g., computer programs and computer program products) for performing a portion or all of the methods described herein. Such a program implementing the invention may be stored on a computer readable medium or may be in the form of one or more signals. Such a signal may be downloaded from an internet website or provided on a carrier signal or in any other form.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The invention can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The usage of the words first, second and third, etcetera do not indicate any ordering. These words may be interpreted as names.

Claims

1. A ranging apparatus, comprising:

a transmitter for transmitting a sequence of light pulses;

2. A ranging device as claimed in claim 1, characterized in that the effective focal length of the collimating element is greater than or equal to 10 times the effective focal length of the first pre-shaping element and/or the effective focal length of the converging element is greater than or equal to 10 times the effective focal length of the second pre-shaping element.

3. A ranging device as claimed in claim 1, characterized in that at least two of the optical axis of the exit of the emitter, the optical axis of the first pre-shaping element and the optical axis of the collimating element are coaxial, and the distance between the exit face of the emitter and the first pre-shaping element is smaller than the focal length of the first pre-shaping element.

4. A ranging device as claimed in claim 3, characterized in that the light exit surface of the emitter is located between the backward focus of the collimating element and the first pre-shaping element.

5. A ranging device as claimed in claim 1, characterized in that the first optical system comprises said collimating element and said first pre-shaping element, the exit face of said emitter being located at the focal plane of said first optical system;

and/or the presence of a gas in the gas,

the second optical system comprises the converging element and the second pre-shaping element, and the detector comprises a photosensitive surface, which is located at a focal plane of the second optical system.

6. A ranging apparatus as claimed in claim 5, characterized in that the effective divergence angle of the light pulse train emitted by the emitter is less than or equal to 180 xD/(π x f), where D is the effective aperture of the collimating element and f is the focal length of the first optical system.

7. A ranging apparatus as claimed in claim 5, characterized in that the effective acceptance angle α of the probe satisfies the following formula:

α≤180×D/(π×f)，

8. A ranging apparatus as claimed in claim 1 wherein the effective divergence angle of the light pulse train emitted by the emitter is less than the effective acceptance angle of the detector.

9. A ranging apparatus as claimed in claim 5 wherein the effective photosensitive size of the detector is greater than or equal to 2 times the size of the airy disk of the second optical system.

10. A ranging apparatus as claimed in claim 9 wherein the effective photosensitive size of the detector is greater than or equal to 2 times the diameter of the airy disk of the second optical system.

11. A ranging apparatus as claimed in claim 1 wherein the effective photosensitive dimension of the detector is greater than the effective light emitting dimension of the emitter.

12. A ranging apparatus as claimed in claim 1 wherein the shape of the light-sensitive surface of the probe comprises a circle, an ellipse or a rectangle.

13. A ranging device as claimed in claim 5, characterized in that said first optical system has an effective focal length ranging between 20mm and 200mm and/or said second optical system has an effective focal length ranging between 20mm and 200 mm.

14. A ranging device as claimed in claim 5, characterized in that the light exit surface of the emitter is placed at the back focal plane of the first optical system.

15. A ranging apparatus as claimed in claim 5 wherein the light sensitive surface of the detector is located at the back focal plane of the second optical system.

16. A ranging apparatus as claimed in claim 1 wherein the transmitter and the first pre-shaping element are integrally encapsulated; and/or

The detector and the second pre-shaping element are integrally packaged.

17. The ranging apparatus as claimed in claim 16, wherein the ranging apparatus further comprises:

18. A ranging device as claimed in claim 17, characterized in that the first sealing body and the first pre-shaping element are integrally formed and/or the second sealing body and the second pre-shaping element are integrally formed.

19. The ranging apparatus as claimed in claim 16, wherein the ranging apparatus further comprises:

the base plate is used for bearing the emitter and is attached to a circuit board;

20. A ranging device as claimed in claim 19, characterized in that said first pre-shaping element is fixed at said light-transmitting area by means of gluing or welding.

21. A ranging apparatus as claimed in claim 19 further comprising a support on which the first pre-shaping element is arranged to be secured by the support.

22. The ranging apparatus as claimed in claim 21, wherein the ranging apparatus further comprises:

the substrate is used for bearing the detector and is attached to a circuit board;

23. A ranging device as claimed in claim 22 wherein the second pre-shaping element is secured to the light transmitting region by means of gluing or welding.

24. A ranging apparatus as claimed in claim 22 wherein the second pre-shaping element is provided on the support to be secured by the support.

25. The ranging apparatus as claimed in claim 1,

the second pre-shaping element comprises an aspheric lens.

26. A ranging device as claimed in claim 1, characterized in that the focal length of the first pre-shaping element ranges between 10 μm and 10mm, and/or,

27. A ranging device as claimed in claim 1, characterized in that the collimating element comprises a spherical lens group, and/or,

the converging element comprises a spherical lens or a spherical lens group.

28. A ranging device as claimed in claim 1, characterized in that the effective aperture of the collimating element is above 20mm, and/or,

the effective aperture of the converging element is above 20 mm.

29. A ranging apparatus as claimed in any of claims 1 to 28 wherein the collimating element and the converging element are one and the same transceiver lens.

30. The ranging apparatus of claim 29, wherein the ranging apparatus further comprises:

31. A ranging apparatus as claimed in claim 30 wherein the optical path altering component is located on the same side of the transceiver lens as the transmitter and the detector.

32. The ranging apparatus as claimed in claim 30, wherein at least one of the detector and the transmitter is disposed at one side of an optical axis of the transceiving lens.

33. A ranging apparatus as claimed in claim 30 wherein the distance from the transmitter to the path-altering component is equal to the distance from the detector to the path-altering component.

34. A ranging apparatus as claimed in claim 30 wherein the optical path altering element is offset from the optical axis of the transceiver lens for projecting the optical pulse train emitted by the emitter towards the peripheral field of view of the transceiver lens.

35. A ranging apparatus as claimed in claim 30 wherein the optical path altering component comprises a mirror and/or a prism.

36. The range finder device of claim 35, wherein the reflector comprises at least one of a flat reflector, a concave reflector.

37. A ranging apparatus as claimed in claim 30 wherein the light path altering element comprises a mirror provided with a light transmitting region, wherein at least a portion of one of the sequence of light pulses emitted by the emitter and the return light reflected by the object is transmitted through the light transmitting region and at least a portion of the other light is reflected by an edge of the mirror.

38. The range finder device of claim 37, wherein the light-transmissive region comprises an opening provided on the reflector, or wherein the light-transmissive region comprises an antireflection film provided on the reflector.

39. A ranging apparatus as claimed in claim 30 wherein the light path altering element comprises a mirror, wherein at least a portion of one of the train of light pulses emitted by the emitter and the return light reflected by the object is transmitted outside an edge of the mirror and at least a portion of the other light is reflected by the mirror.

40. A ranging apparatus as claimed in claim 37 wherein at least a portion of the light pulse train emitted by the emitter passes through the optically transparent region, wherein the light pulse train impinges on the path altering element with a spot area greater than or equal to the area of the optically transparent region.

41. A ranging apparatus as claimed in claim 39 wherein at least part of the train of light pulses emitted by the emitter is reflected by the mirror to the transceiver lens and at least part of the return light reflected by the object is projected from outside the edge of the mirror to the detector.

42. A ranging apparatus as claimed in any of claims 1 to 28 wherein the probe comprises:

43. The ranging apparatus as claimed in any one of claims 1 to 28, wherein the ranging apparatus further comprises:

44. A ranging apparatus as claimed in any of claims 1 to 28 wherein the ranging apparatus comprises a lidar.

45. A mobile platform, comprising:

a ranging apparatus as claimed in any of claims 1 to 44; and

the platform body, range unit installs on the platform body.

46. The mobile platform of claim 45, wherein the mobile platform comprises a drone, a robot, a vehicle, or a boat.