Distance detection device

Abstract

An embodiment of the utility model discloses a distance detection device, which comprises a light source, a transmitting light path shaping lens group, a light path changing element, a receiving light path shaping lens group and a receiver, the transmitting light path shaping lens group shapes light beams emitted by the light source, and a first included angle is formed between the emergent direction of the shaped light beams in a collimation state and the horizontal direction. According to the distance detection device, the light beams in the collimation state are inclined, so that return light loss caused by avoidance design on the light path changing element when emergent light and return light are coaxial is avoided, the energy of the received return light containing target information is increased, and the precision of target information detection is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of laser detection, and particularly relates to a distance detection device. Background Art

[0002] Laser ranging is a method for accurately measuring the distance to a target. During operation, a thin laser beam is emitted from a light source towards the target object to be detected. A photoelectric element receives the laser beam reflected by the target object to be detected, and a timer measures the time from the emission to the reception of the laser beam to calculate the distance from the observer to the target object to be detected. To achieve accurate measurement, it is necessary to shape the laser beam emitted by the light source. For example, the beam is shaped to obtain a beam with better collimation. At the same time, the overly weak reflected return light signal will also affect the detection accuracy. Therefore, it is necessary to ensure that the signal intensity of the return light is sufficient.

[0003] The processes of emitting the beam, shaping the beam, and receiving the return light are realized in the distance detection device. Most current distance detection devices adopt the method of vertical incidence of the coaxial optical path on the target, that is, the light source, the focusing lens group, the target object to be detected, the reflector, etc. are arranged along the same axis, and the focusing lens group is used to shape the beam into a parallel beam and vertically incident on the target surface. Since the optical path of the return light coincides with the optical path of the emitted beam, a transmissive central circular hole area is set on the reflector to avoid the emitted beam, and the return light energy containing target information is collected by reflection through the non-central circular hole area around. This causes some of the return light containing target information to pass through the central circular hole of the reflector and be transmitted without being reflected and collected, resulting in a loss of return light energy, and the loss can reach more than 30%, greatly reducing the detection accuracy of the device for target information. Summary of the Utility Model

[0004] In view of this, an embodiment of the utility model provides a distance detection device, which tilts the collimated beam after shaping, avoiding the loss of return light caused by the avoidance design on the optical path changing element when the emitted light and the return light are coaxial, increasing the return light energy containing target information received, and improving the detection accuracy of the target information.

[0005] In a first aspect, an embodiment of the utility model provides a distance detection device, including:

[0006] A light source for emitting a beam;

[0007] An emission optical path shaping lens group disposed on the emission optical path of the light source for collimating the beam emitted by the light source into a parallel light for emission, and the emission direction of the parallel light forms a first included angle with the horizontal direction;

[0008] An optical path changing element is arranged on the outgoing optical path of the emission optical path shaping lens group. The optical path changing element forms a second included angle with the horizontal direction, and the optical path changing element is configured to transmit the light beam from the light source and reflect the return light reflected by the target detector;

[0009] A receiving optical path shaping lens group is placed on one side of the optical path changing element and is configured to receive the return light reflected by the optical path changing element and converge the received return light;

[0010] A receiver is arranged on the outgoing optical path of the receiving optical path shaping lens group and is configured to receive the converged return light and convert the received return light into an electrical signal, and the electrical signal is used to measure the distance between the target detector and the distance detection device.

[0011] Preferably, the outgoing optical path and the optical path of the return light reflected by the target detector form a third included angle, and the third included angle is twice the first included angle. The return light reflected by the optical path changing element perpendicularly enters the receiving optical path shaping lens group.

[0012] Preferably, the third included angle and the second included angle satisfy the following relationship:

[0013] β = 4β - 180°

[0014] Wherein, θ represents the angle size of the third included angle, and β represents the angle size of the second included angle.

[0015] Preferably, the angle range of the second included angle is 46° to 48°, and the angle range of the third included angle is 4° to 12°.

[0016] Preferably, the optical path changing element includes a transmission part and a reflection part. The reflection part is located above the transmission part, and the ratio of the area of the reflection part to the area of the transmission part is greater than or equal to 4:1.

[0017] Preferably, the optical path changing element includes:

[0018] A polarizer;

[0019] A quarter-wave plate is arranged in parallel on the side of the polarizer away from the emission optical path shaping lens group, and the polarization direction of the polarizer forms a fourth included angle with the fast axis direction of the quarter-wave plate.

[0020] Preferably, the polarizer is configured to output the polarization state of the light beam from the light source as a linearly polarized state. The quarter-wave plate is configured to output the light beam in a linearly polarized state as a circularly polarized light through the quarter-wave plate. The quarter-wave plate also outputs the reflected light in a circularly polarized state from the target detector as a linearly polarized light. The polarizer reflects the reflected light in a linearly polarized state, causing the reflected light to enter the receiving optical path shaping lens group.

[0021] Preferably, the transmitting optical path shaping lens group and the receiving optical path shaping lens group include at least one converging lens.

[0022] Preferably, the transmitting optical path shaping lens group and the receiving optical path shaping lens group further include at least one mirror.

[0023] In a second aspect, an embodiment of the present invention provides a distance detection device, including:

[0024] A receiver;

[0025] Two light sources, symmetrically arranged on both sides of the receiver, for emitting light beams;

[0026] Two transmitting optical path shaping lens groups, respectively arranged on the outgoing light paths of the two light sources, and the two light sources are respectively offset on one side of the optical axes of the two transmitting optical path shaping lens groups away from the receiver. The transmitting optical path shaping lens group is configured to shape the light beam emitted by the light source into a divergent light beam on the side close to the receiver for output;

[0027] A receiving optical path shaping lens group, arranged between the two transmitting optical path shaping lens groups and located on the incident light path of the receiver, is configured to receive the reflected light reflected by the target detector and converge and send the received reflected light to the receiver for processing.

[0028] Preferably, the transmitting optical path shaping lens group includes at least one offset lens, arranged on the outgoing light path of the light source, for shaping the light beam.

[0029] Preferably, the receiving optical path shaping lens group includes:

[0030] At least one receiving lens, arranged on the side far from the receiver, for shaping the divergent reflected light reflected by the target detector into parallel reflected light;

[0031] At least one concentrating lens, coaxially arranged on the outgoing light path of the receiving lens, for converging the parallel reflected light.

[0032] An embodiment of the present application provides a distance detection device. The distance detection device includes a light source, an emission optical path shaping lens group, an optical path changing element, a reception optical path shaping lens group, and a receiver. The emission optical path shaping lens group shapes the light beam emitted by the light source, and the emission direction of the collimated light beam after shaping forms a first included angle with the horizontal direction. This distance detection device tilts the collimated light beam, avoiding the loss of reflected light caused by the avoidance design on the optical path changing element when the emitted light and the reflected light are coaxial, increasing the energy of the reflected light containing target information received, and improving the accuracy of detecting target information. Description of the Drawings

[0033] Through the following description of the embodiments of the present utility model with reference to the drawings, the above and other objects, features, and advantages of the present utility model will become clearer. In the drawings:

[0034] Figure 1 is the structural plan view of the distance detection device according to Embodiment 1 of the present utility model;

[0035] Figure 2 is the structural plan view of the distance detection device according to Embodiment 2 of the present utility model;

[0036] Figure 3 is the plan view of the distance detection device according to Embodiment 3 of the present utility model;

[0037] Figure 4 is the structural and optical path plan view of the receiving lens and the concentrating lens in Embodiment 3 of the present utility model;

[0038] Figure 5 is the structural and optical path plan view of the offset lens in Embodiment 3 of the present utility model.

[0039] Description of the Reference Numerals:

[0040] 10 - Light source; 20 - Emission optical path shaping lens group; 21 - Offset lens; 30 - Optical path changing element; 31 - Transmission part; 32 - Reflection part; 33 - Polarizer; 34 - Quarter-wave plate; 40 - Reception optical path shaping lens group; 41 - Receiving lens; 42 - Concentrating lens; 5 - Receiver; 6 - Light beam; 70 - First included angle; 71 - Second included angle; 72 - Third included angle; 8 - Target detection object. Detailed Embodiments

[0041] The following is a description of the present application based on embodiments, but the present application is not limited to these embodiments. In the following detailed description of the present application, some specific details are described in detail. Those skilled in the art can fully understand the present application without the description of these details. To avoid obscuring the essence of the present application, well-known methods, processes, procedures, elements, and circuits are not described in detail.

[0042] In addition, those of ordinary skill in the art should understand that the attached drawings provided herein are for illustrative purposes only, and the drawings are not necessarily drawn to scale.

[0043] Unless otherwise clearly defined or limited, terms such as "installed", "connected", "joined", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] For ease of description, spatially relative terms such as "inner", "outer", "below", "beneath", "lower", "above", "upper", etc. are used herein to describe the relationship between one element or feature illustrated in the drawings and another element or feature. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the drawings. For example, if the device in the drawings is flipped, the element described as "below" or "beneath" another element or feature will then be positioned "above" that other element or feature. Thus, the exemplary term "below" can encompass both the above and below orientations. The device can be oriented in other ways (rotated 90 degrees or in other orientations), and the spatially relative descriptive terms used herein should be interpreted accordingly.

[0045] Unless the context clearly requires otherwise, words such as "including", "comprising", etc. throughout the application document should be interpreted in an inclusive sense rather than an exclusive or exhaustive sense; that is, in the sense of "including but not limited to".

[0046] In the description of this application, it should be understood that terms such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise stated, the meaning of "a plurality" is two or more.

[0047] The distance detection device according to the embodiment of the present application tilts the emitted light beam 6, so that the optical path of the emitted light and the optical path of the reflected return light from the target detection object 8 are set as non-coaxial optical paths, avoiding the return light loss caused by the need for avoidance design in the structure when the emitted light and the return light are coaxial, increasing the energy of the received return light containing target information, and improving the accuracy of detecting target information.

[0048] Embodiment 1:

[0049] Refer to Figure 1, the distance detection device includes a light source 10, a transmitting optical path shaping lens group 20, an optical path changing element 30, a receiving optical path shaping lens group 40, and a receiver 5. The light source 10 is used to emit a light beam 6, and the light beam 6 can be ordinary laser light or polarized light in a certain polarization state.

[0050] The transmitting optical path shaping lens group 20 is arranged on the outgoing optical path of the light source 10 and is used to collimate the light beam 6 emitted by the light source 10 into a parallel light beam for outgoing, so as to reduce the divergence of the light beam 6 on the optical path, avoid the influence of light energy loss on the measurement accuracy, and improve the accuracy of laser ranging. The transmitting optical path shaping lens group 20 can be composed of one or more lenses to collimate the light beam 6, so that during the process of outgoing to the target detector 8 and being reflected back to the distance detection device, the cross-sectional area of the parallel light beam 6 remains unchanged. The transmitting optical path shaping lens group 20 can also include one or more reflectors to guide the propagation direction of the light beam 6, so that the outgoing collimated light is inclined, so as to realize the non-coaxial setting of the outgoing light and the returning light, reduce the light energy loss caused by the avoidance design, and improve the detection accuracy. After the light beam 6 passes through the transmitting optical path shaping lens group 20, the outgoing direction of the finally formed parallel light beam forms a first included angle 70 with the horizontal direction.

[0051] The optical path changing element 30 is arranged on the outgoing optical path of the transmitting optical path shaping lens group 20 and is used to transmit the light beam 6 from the light source 10 and reflect the returning light reflected by the target detector 8, guiding the outgoing light beam 6 and the returning light to different directions. While the outgoing light is inclined to be emitted, the returning light can be reflected vertically into the receiving optical path shaping lens group 40 through the reflection of the optical path changing element 30. The optical path changing element 30 forms a second included angle 71 with the horizontal direction.

[0052] In this embodiment, the optical path changing element 30 includes a transmission part 31 and a reflection part 32. Among them, the transmission part 31 is used to transmit the parallel light beam 6 shaped by the transmitting optical path shaping lens group 20, so that it emits from the distance detection device and is emitted to the target detector 8. The reflection part 32 is used to reflect the returning light reflected by the target detector 8, change the propagation direction of the returning light, and reflect the obliquely incident returning light vertically into the receiving optical path shaping lens group 40. The reflection part 32 is located above the transmission part 31, that is, the parallel light beam 6 collimated by the transmitting optical path shaping lens group 20 passes obliquely upward through the transmission part 31 to the target detector 8 at a first included angle 70, and the obliquely incident returning light reflected by the target detector 8 is reflected on the reflection part 32 after entering the distance detection device. At this time, the outgoing light beam 6 and the incident returning light are in a non-coaxial state, that is, the returning light does not pass through the transmission part 31 but only reflects on the reflection part 32, avoiding the light energy loss caused by the returning light transmitting through the transmission part 31 and improving the detection accuracy.

[0053] Among them, the area ratio of the reflection part 32 to the transmission part 31 can be a ratio greater than or equal to 4:1, and the shapes of the transmission part 31 and the reflection part 32 can also be designed and changed according to actual needs. Since the emission optical path shaping lens group 20 shapes the light beam 6 into a parallel light with a constant cross-sectional area during propagation, the transmission part 31 does not need to occupy a large area on the optical path changing element 30, enabling the reflection part 32 to have a larger area ratio to reflect more return light, further reducing the light energy loss of the return light and improving the detection accuracy.

[0054] The outgoing optical path and the optical path of the return light reflected by the target object form a third included angle 72. At this time, since the normal line of the light beam 6 when reflected by the target object is in the horizontal direction, its incident angle is actually the same as the first included angle 70 in size. The third included angle 72 formed by the light beam 6 emitted from the emission optical path shaping lens group 20 and the return light is the sum of the incident angle and the exit angle when the light beam 6 is reflected by the target object. That is to say, the third included angle 72 is twice the first included angle 70.

[0055] Optionally, the third included angle 72 and the second included angle 71 satisfy the following relationship:

[0056] θ = 4β - 180°

[0057] Among them, θ represents the angle size of the third included angle 72, and β represents the angle size of the second included angle 71. Under this angular relationship, the design of the first included angle 70 and the second included angle 71 enables the return light reflected by the optical path changing element 30 to perpendicularly enter the receiving optical path shaping lens group 40. At this time, the return light is guided by the internal mirror of the receiving optical path shaping lens group 40 and shaped by the lens, and finally becomes a converging light beam.

[0058] Optionally, the angle range of the second included angle 71 is 46° - 48°, and the angle range of the third included angle 72 is 4° - 12°.

[0059] In a preferred embodiment, the angle of the third included angle 72 can be selected as 6°, and at the same time, the angle of the second included angle 71 is 46.5°, and the angle of the first included angle 70 is 3°.

[0060] The receiving optical path shaping lens group 40 is placed on one side of the optical path changing element 30, used to receive the return light reflected by the optical path changing element 30, and converge the received return light, so that the parallel return light converges into a spot with a very small cross-sectional area, further improving the accuracy of laser ranging. The receiving optical path shaping lens group 40 can be composed of one or more lenses and mirrors to guide the propagation direction of the return light and achieve the effect of converging the return light. Since the return light reflected by the optical path changing element 30 can perpendicularly enter, there is no need to perform an additional tilting setting on the receiving optical path shaping lens group 40, reducing the overall size of the distance detection device.

[0061] The receiver 5 is arranged on the outgoing light path of the receiving optical path shaping lens group 40 and is used to receive the converged return light, that is, the receiving optical path shaping lens group 40 converges the return light into the receiver 5. At the same time, the receiver 5 performs photoelectric conversion, converts the received converged return light into an electrical signal, and determines the reception time of the return light through the electrical signal. After knowing the emission time of the light beam 6 and the reception time of the return light, the distance between the target detector and the distance detection device can be determined by calculation.

[0062] Optionally, the transmitting optical path shaping lens group 20 and the receiving optical path shaping lens group 40 include at least one converging lens. For example, the light source 10 is arranged at the focal point of the converging lens of the transmitting optical path shaping lens group 20, and the emitted light beam 6 is output as parallel light through the converging lens. For another example, the receiver 5 is arranged at the focal point of the converging lens of the receiving optical path shaping lens group 40, and the parallel return light reflected by the optical path changing element 30 is output as converging light through the converging lens and focused on the receiver 5.

[0063] Optionally, the transmitting optical path shaping lens group 20 and the receiving optical path shaping lens group 40 further include at least one mirror. For example, the mirror of the transmitting optical path shaping lens group 20 guides the light beam 6 shaped into parallel light so that it can accurately exit from the housing of the distance detection device while maintaining the first included angle 70 unchanged. For another example, the mirror of the receiving optical path shaping lens group 40 guides the vertically incident return light to be coaxial with the converging lens inside it, so that the parallel return light can be converged to the receiver 5 through the converging lens.

[0064] In the distance detection device of this embodiment, the light beam 6 is obliquely emitted, so that the outgoing light path and the return light path reflected by the target detector 8 are non-coaxial light paths, avoiding the return light loss caused by the need for an avoidance design in the structure when the outgoing light and the return light are coaxial. At the same time, in the case where the outgoing light and the return light are in non-coaxial light paths, the optical path changing element 30 is set to a structure having a transmission part 31 and a reflection part 32, and the reflection part 32 is arranged above the transmission part 31, avoiding the light energy loss caused by the return light transmitting through the transmission part 31, and also making the area ratio of the reflection part 32 larger, capable of reflecting more return light, further reducing the light energy loss of the return light, improving the detection accuracy, and increasing the energy of the received return light containing target information.

[0065] Embodiment 2:

[0066] Refer to Figure 2, the distance detection device includes a light source 10, a transmitting optical path shaping lens group 20, an optical path changing element 30, a receiving optical path shaping lens group 40, and a receiver 5. The light source 10, the transmitting optical path shaping lens group 20, the receiving optical path shaping lens group 40, and the receiver 5 in this embodiment are basically the same as those in Embodiment 1, and will not be elaborated here. The difference between this embodiment and Embodiment 1 lies only in the optical path changing element 30.

[0067] In this embodiment, as Figure 2 shown, the optical path changing element 30 includes a polarizer 33 and a quarter-wave plate 34. The quarter-wave plate 34 is arranged parallel to the side of the polarizer 33 away from the transmitting optical path shaping lens group 20. The polarizer 33 and the quarter-wave plate 34 are parallel to each other, and can be arranged at a certain distance or closely. For example, the polarizer 33 and the quarter-wave plate 34 can be bonded into one body by an optical cementing process. The polarizer 33 and the quarter-wave plate 34 realize the transmission of the outgoing light and the reflection of the return light by changing the polarization states of the light beam 6 and the return light. The polarizer 33 and the quarter-wave plate 34 form a second included angle 71 with the horizontal direction, so that after the return light is reflected by the polarizer 33, it can vertically enter the receiving optical path shaping lens group 40. At this time, there is no need to perform an additional inclination setting on the receiving optical path shaping lens group 40, reducing the overall size of the distance detection device. At the same time, the design of non-coaxial outgoing light and return light also avoids the interference of the outgoing light on the return light when the outgoing light and the return light are coaxial, reduces the loss of the return light energy, and improves the detection accuracy.

[0068] In this embodiment, the included angle between the optical path changing element 30 composed of the polarizer 33 and the quarter-wave plate 34 and the horizontal direction is the same as the included angle between the optical path changing element 30 having a transmission part 31 and a reflection part 32 and the horizontal direction in Embodiment 1, and the angular relationship between the formed second included angle 71 and the first included angle 70 and the third included angle 72 is also basically the same as the angular relationship between the second included angle 71 and the first included angle 70 and the third included angle 72 in Embodiment 1, and will not be elaborated here.

[0069] The polarizer 33 outputs the polarization state of the light beam 6 from the light source 10 as a linearly polarized state, and the quarter-wave plate 34 outputs the light beam 6 in a linearly polarized state as a circularly polarized light through the quarter-wave plate 34. The quarter-wave plate 34 also outputs the return light in a circularly polarized state reflected by the target detection object as a linearly polarized light, and the polarizer 33 reflects the return light in a linearly polarized state, so that the return light can enter the receiving optical path shaping lens group 40.

[0070] Specifically, when the emitted light beam 6 passes through the optical path changing element 30, it first passes through the polarizer 33 and exits in a linearly polarized state, and then enters the quarter-wave plate 34. Since the fast axis and slow axis of the quarter-wave plate have different refractive indices, the linearly polarized light beam 6 generates a phase delay of 1 / 4 phase difference in the directions along the fast axis and slow axis respectively, and finally the light beam 6 exits the optical path changing element 30 in a circularly polarized state.

[0071] Since the light beam 6 exits in a circularly polarized state, the reflected return light from the target detector is also in a circularly polarized state. When the return light passes through the optical path changing element 30, it first passes through the quarter-wave plate 34. The return light in the circularly polarized state generates a phase delay of 1 / 4 phase difference in the directions along the fast axis and slow axis again, and finally forms return light in a linearly polarized state perpendicular to the polarization direction of the polarizer 33. For example, when the light beam 6 passes through the polarizer 33 to become linearly polarized light with a polarization direction parallel to the polarizer 33, the polarization direction of the return light after passing through the quarter-wave plate 34 is perpendicular to the polarization direction of the polarizer 33. At the same time, the polarizer 33 can only transmit linearly polarized light with the same polarization direction as itself. Since the polarization direction of the return light is perpendicular to the polarization direction of the polarizer 33, the return light cannot pass through the polarizer 33, but will be reflected by the polarizer 33 and perpendicularly enter the receiving optical path shaping lens group 40, realizing the change of the return light optical path.

[0072] Optionally, the polarization direction of the polarizer 33 forms a fourth included angle with the fast axis direction of the quarter-wave plate 34. The angle of the fourth included angle can be 45°. When the angle of the fourth included angle is 45°, the linearly polarized light along the polarization direction of the polarizer 33 just forms components with perpendicular directions and equal amplitudes on the fast axis and slow axis of the quarter-wave plate 34 respectively. After these two components generate a phase delay of 1 / 4, they just form polarized light in a circularly polarized state.

[0073] In the distance detection device of this embodiment, by tilting the emitted light beam 6, the emitted light optical path and the return light optical path reflected by the target detector 8 are non-coaxial optical paths, avoiding the return light loss caused by the need for avoidance design in the structure when the emitted light and the return light are coaxial. At the same time, in the case where the emitted light and the return light are in non-coaxial optical paths, the optical path changing element 30 is set to be composed of the polarizer 33 and the quarter-wave plate 34. By changing the polarization states of the light beam 6 and the return light, and using the characteristic that the polarizer 33 can only transmit linearly polarized light with the same polarization direction as itself, the polarization state of the return light incident on the surface of the polarizer 33 is changed to linearly polarized light perpendicular to its polarization direction, avoiding the light energy loss caused by the transmission of the return light through the polarizer 33, increasing the energy of the received return light containing target information, and improving the detection accuracy.

[0074] Embodiment Three:

[0075] Refer to Figure 3, the distance detection device according to the embodiment of the present application includes a receiver 5, two light sources 10, two transmitting optical path shaping lens groups 20, and a receiving optical path shaping lens group 40. The two light sources 10 are symmetrically arranged on both sides of the receiver 5 and are used for emitting light beams 6. The light beam 6 can be ordinary laser light or laser light in a certain polarization state.

[0076] The two transmitting optical path shaping lens groups 20 are respectively arranged on the outgoing optical paths of the two light sources 10 and are used for shaping the light beam 6 emitted by the light source 10 into a divergent light beam that is emitted toward the side close to the receiver 5, so as to avoid part of the light beam 6 being emitted toward the outside away from the receiver 5, resulting in light energy loss due to the reflected light not being able to return to the distance detection device. The divergent light generates diffuse reflection when encountering the target detection object 8. At the same time, the two light sources 10 are respectively offset to the side away from the receiver 5 on the optical axes of the two transmitting optical path shaping lens groups 20. Therefore, the normal line when the light beam 6 reflects with the target detection object 8 is close to the side of the receiver 5, and the reflected light generated by the diffuse reflection of the light beam 6 propagates toward the side close to the receiver 5, so that most of the reflected light can be received and processed by the receiving optical path shaping lens group 40, reducing the loss of the light energy of the reflected light.

[0077] The receiving optical path shaping lens group 40 is arranged between the two transmitting optical path shaping lens groups 20 and is located on the incident optical path of the receiver 5. For example, the receiving optical path shaping lens group 40 and the receiver 5 can be arranged in the middle of the two transmitting optical path shaping lens groups 20, or can be arranged at a position biased to one side between the two transmitting optical path shaping lens groups 20 according to the detection requirements and the adjustment of the optical path. For example, when the surface shape of the target detection object 8 close to the distance detection device is relatively special, the position of the receiver 5 is adjusted so that when calculating the emission time and reception time of the transmitted light and the reflected light, the comprehensive result can reflect the actual position of the target detection object 8. The receiving optical path shaping lens group 40 is used for receiving the reflected light reflected by the target detection object and converging and sending the received reflected light to the receiver 5 for processing. Through photoelectric conversion, the received converged reflected light is converted into an electrical signal, and the reception time of the reflected light is determined through the electrical signal. After knowing the emission time of the light beam 6 and the reception time of the reflected light, the distance between the target detection object 8 and the distance detection device can be determined by calculation.

[0078] Optionally, the transmitting optical path shaping lens group 20 includes at least one offset lens 21, which is arranged on the outgoing optical path of the light source 10 and is used for shaping the light beam 6. Refer to Figure 5, the offset lens 21 can be a converging lens or a diverging lens. For example, multiple offset lenses 21 are provided, and the converging lens among them is arranged closer to the light source 10, and the light source 10 is offset on its optical axis away from the receiver 5. This converging lens collimates the light beam 6 emitted by the light source 10 and deflects it towards the side closer to the receiver 5. At the same time, the diverging lens in the offset lens 21 is arranged on the side away from the light source 10 to diverge the light beam 6 shaped to the side closer to the receiver 5 into diverging light towards the side closer to the receiver 5, preventing a part of the light beam 6 from being emitted to the outside away from the receiver 5, resulting in light energy loss due to the return light not being able to return to the distance detection device.

[0079] Optionally, the receiving optical path shaping lens group 40 includes at least one receiving lens 41 and at least one concentrating lens 42. Referring to Figure 4 , at least one receiving lens 41 is arranged on the side away from the receiver 5 for shaping the diverging return light reflected by the target detector 8 into parallel return light. The receiving lens 41 can be a diverging lens for collecting the diverging return light after diffuse reflection on the surface of the target detector 8. For example, two diverging lenses are provided. The diverging lens on the side away from the receiver 5 refracts the diverging light to reduce the angle between it and the optical axis; the diverging lens closer to the receiver 5 further refracts the processed diverging light to make it in a collimated state or a state of propagating towards the optical axis side, so as to further converge the return light and increase the detection accuracy.

[0080] At least one concentrating lens 42 is coaxially arranged on the outgoing optical path of the receiving lens 41 for converging the parallel return light. The concentrating lens 42 can be a converging lens for converging the return light in a collimated state or a state of propagating towards the optical axis side to form a spot with an extremely small cross-sectional area on the receiver 5, improving the accuracy of distance measurement. For example, a converging lens with its focal point exactly falling on the receiving surface of the receiver 5 is selected as the concentrating lens 42. This concentrating lens 42 converges the return light in a collimated state or a state of propagating towards the optical axis side to the focal point, that is, on the receiving surface of the receiver 5, for further photoelectric conversion and processing of the generated electrical signals to achieve accurate measurement of distance detection.

[0081] The distance detection device in this embodiment uses the transmitting optical path shaping lens group 20 to shape the light beam 6 into outgoing light deflected towards the side closer to the receiver 5, making the outgoing light optical path form a non-coaxial optical path with the return light optical path reflected by the target detector 8, avoiding the return light loss caused by the need for avoidance design in the structure when the outgoing light and the return light are coaxial. At the same time, in actual situations, two light sources 10 and the receiver 5 between them are used to cooperate in distance measurement. By changing the position of the receiver 5, distance detection can be carried out for target detectors 8 with different surface shapes. The receiving optical path shaping lens group 40 is used to shape and collect the diverging return light, reducing the loss of return light energy and improving the accuracy of distance detection.

[0082] The foregoing are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, various modifications and variations can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. A distance detection device, characterized in that, The distance detection device includes: a light source (10) for emitting a light beam (6); a transmitting optical path shaping lens group (20) disposed on the outgoing optical path of the light source (10) for collimating the light beam (6) emitted by the light source (10) into a parallel light beam for outgoing, and the outgoing direction of the parallel light beam forms a first included angle (70) with the horizontal direction; an optical path changing element (30) disposed on the outgoing optical path of the transmitting optical path shaping lens group (20), the optical path changing element (30) forms a second included angle (71) with the horizontal direction, and the optical path changing element (30) is configured to transmit the light beam (6) from the light source (10) and reflect the return light reflected by the target detection object; a receiving optical path shaping lens group (40) placed on one side of the optical path changing element (30), and is configured to receive the return light reflected by the optical path changing element (30) and converge the received return light; a receiver (5) disposed on the outgoing optical path of the receiving optical path shaping lens group (40), and is configured to receive the converged return light and convert the received return light into an electrical signal, and the electrical signal is used to measure the distance between the target detection object and the distance detection device.

2. The distance detection device according to claim 1, characterized in that, The outgoing optical path and the optical path of the return light reflected by the target detection object form a third included angle (72), and the third included angle (72) is twice the first included angle (70), and the return light reflected by the optical path changing element (30) vertically enters the receiving optical path shaping lens group (40).

3. The distance detection device according to claim 2, characterized in that, The third included angle (72) and the second included angle (71) satisfy the following relationship: θ = 4β - 180° where θ represents the angle size of the third included angle (72), and β represents the angle size of the second included angle (71).

4. The distance detection device according to claim 3, wherein, The angle range of the second included angle (71) is 46° to 48°, and the angle range of the third included angle (72) is 4° to 12°.

5. The distance detection device according to claim 1, characterized in that, The optical path changing element (30) includes a transmission part (31) and a reflection part (32), the reflection part (32) is located above the transmission part (31), and the area ratio of the reflection part (32) to the area of the transmission part (31) is greater than or equal to 4:

1.

6. The distance detection device according to claim 1, characterized in that, The optical path changing element (30) includes: a polarizer (33); a quarter-wave plate (34) disposed in parallel on the side of the polarizer (33) away from the transmitting optical path shaping lens group (20), and the polarization direction of the polarizer (33) forms a fourth included angle with the fast axis direction of the quarter-wave plate (34).

7. The distance detection device according to claim 6, wherein The polarizer (33) is configured to output the polarization state of the light beam (6) from the light source (10) as a linearly polarized state. The quarter-wave plate (34) is configured to output the light beam (6) in a linearly polarized state as circularly polarized light through the quarter-wave plate (34). The quarter-wave plate (34) also outputs the reflected light in a circularly polarized state from the target object to be detected as linearly polarized light. The polarizer (33) reflects the reflected light in a linearly polarized state, so that the reflected light enters the receiving optical path shaping lens group (40).

8. The distance detection device according to claim 1, characterized in that The transmitting optical path shaping lens group (20) and the receiving optical path shaping lens group (40) include at least one converging lens.

9. The distance detection device according to claim 1, characterized in that, The transmitting optical path shaping lens group (20) and the receiving optical path shaping lens group (40) further include at least one reflector.

10. A distance detection device, characterized in that, The distance detection device includes: a receiver (5); two light sources (10), symmetrically arranged on both sides of the receiver (5) for emitting light beams (6); two transmitting optical path shaping lens groups (20), respectively arranged on the outgoing optical paths of the two light sources (10), and the two light sources (10) are respectively offset on one side of the optical axes of the two transmitting optical path shaping lens groups (20) away from the receiver (5). The transmitting optical path shaping lens group (20) is configured to shape the light beam (6) emitted by the light source (10) into a divergent light beam on the side close to the receiver (5) and output it; a receiving optical path shaping lens group (40), arranged between the two transmitting optical path shaping lens groups (20) and on the incident optical path of the receiver (5), and configured to receive the reflected light reflected by the target object to be detected and converge and transmit the received reflected light to the receiver (5) for processing.

11. The distance detection device according to claim 10, wherein The transmitting optical path shaping lens group (20) includes at least one offset lens (21), arranged on the outgoing optical path of the light source (10) for shaping the light beam (6).

12. The distance detection device according to claim 10, characterized in that, The receiving optical path shaping lens group (40) includes: at least one receiving lens (41), arranged on the side far from the receiver (5) for shaping the divergent reflected light reflected by the target object to be detected into parallel reflected light; at least one concentrating lens (42), coaxially arranged on the outgoing optical path of the receiving lens (41) for converging the parallel reflected light.

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